DEPARTMENT OF THE INTERIOR 

UNITED STATES GEOLOGICAL SURVEY 

GEORGE OTIS SMITH, DIRECTOR 

WATER-SUPPLY PAPER 257 

WELL-DRILLING METHODS 

BY 

ISAIAH BOWMAN 

WASHINGTON 

GOVERNMENT PRINTING OFFICE 

1911 
• 
CONTENTS. 

Page. 

Introduction_________________________________________________________ 7 

Purpose of report________________________________________________ 7 

.1\Iethod of treatment. _____________________________________________ · 8 

Acknovvledgrnents_________________________________________________ 9 

Underground vvaters of the United States______________________________ 9 

Amount and distribution of rainfalL_______________________________ 9 

Disposal of rainfalL _________________________________ ~----------- 10 

Ilun-off______________________________________________________ 10 

Evaporation_________________________________________________ 11 

Absorption___________________________________________________ 11 

Amount--------------------------------~---------------- 11 

Factors influencing absorption_____________________________ 12 

Amount of underground vvater_____________________________________ 13 

Artesian conditions._ _________ :_____________________________________ 15 

Water-bearing formations._____________________________________________ 16 

Geologic considerations____________________________________________ 16 

Classes of materiaL______________________________________________ 17 

Sands and gravels____________________________________________ 17 

ClaY~------------------------------------------------·-------- 17 

Till_________________________________________________________ 18 

Sandstone, conglomerate, and quartzite________________________ 19 

Shal~------------------------------------------------------- 19 

Limestone___________________________________________________ 20 

Granite, gneiss, and schist_____________________________________ 20 

Lake and stream deposits._____________________________________ 21 

Oil and gas bearing formations ___________ .:.____________________________ 21 

Structure and character__________________________________________ 21 

Distribution______________________________________________________ 22 

. History of well drilling_______________________________________________ 23 

Asia-------------------------~----------------------------------- 23 

Europe__________________________________________________________ 24 

United States____________________________________________________ 25 

Early drilling________________________________________________ 25 

Driven vvells__________________________________________________ 26 

Well augers__________________________________________________ 26 

Jetting methodl______________________________________________ 26 

Self-cleaning method----------------------------------------- 27 

Spring-pole or churn drilL___________________________________ 27 

Standard method--------------------------------~----------- 28 

Hydraulic rotary method_____________________________________ 30 

Core drills___________________________________________________ 30 

Distribution of drilled vvells__________________________________________ 30 

Methods of well drilling______________________________________________ 32 

Classification____________________________________________________ 32 

Selection of outfit----------------------------------------------- 33 

3 
4 CONTENTS. 

Methods of well drilling-Continued. Page. 

Standard method________________________________________________ 34 

Character and uses__________________________________________ 34 

Outfit_______________________________________________________ 34 

Itig ___________________ ~--------------------------------- 34 

Engine and boiler________________________________________ 37 

Tools___________________________________________________ 38 

Temper screw___________________________________________ 41 

Cable___________________________________________________ 43 

Drilling operations--------,----------------------------------- 45 

Spudding________________________________________________ 45 

Drilling with the walking beam___________________________ 47 

Dressing the bit_________________________________________ 50 

Wet and dry drilling __________________ __:__________________ 51 

Casing the welL_____________________________________________ 51 

Conductor box___________________________________________ 51 

Casing and drive pipe____________________________________ 52 

Portable drilling rig______________________________________________ 56 

Variations in construction____________________________________ 56 

Advantages and disadvantages________________________________ 57 

Percussion core drill ______________________ ------------------------ 59 

Pole-tool method__________________________________________________ 59 

General features_____________________________________________ 59 

Outfit_______________________________________________________ 61 

Drilling operations__________________________________________ 61 

Self-cleaning or hollow-rod method________________________________ 64 

Outfit_______________________________________________________ 64 

Drilling operations___________________________________________ 65 

1Jses________________________________________________________ 66 

California or stovepipe method___________________________________ 66 

Introduction_________________________________________________ 66 

Itig --------------------------------------------------------- 66 

Casing ------------------------------------------------------ 68 

Drilling operations___________________________________________ 68 

Perforation of casing ----------------------------------------- 69 

Advantages__________________________________________________ 70 

Ilydraulic rotary method ---------------------------------------- 70 

Development __________________ ------'-------------------- -- _ _____ 70 

Outfit_______________________________________________________ 71 

Drilling operations ______________________ --- ___ --------------- 71 

Special operations _______________________________________ ----- 7 4 

Advantages nnd disadvantages________________________________ 75 

Jetting method _____________________________ --------------------- 75 

Outfit ------------------------------------------------------- 76 

Drilling operations___________________________________________ 76 

1Jses________________________________________________________ 76 

Core drilling_____________________________________________________ 78 

General features_____________________________________________ 78 

Diamond drilL_______________________________________________ 79 

Outfit___________________________________________________ 79 

Drilling operations ________ ------------------------------- 84 

Calyx drilL ________________________ --------------------------- 84 

Development_____________________________________________ 84 

I>escription______________________________________________ 85 
CONTENT& 5 

Methods of well drilling-Continued. Page. 

Core drilling-Continued. 

Chilled shot method__________________________________________ 86 

Accidents and difficulties_____________________________________ 86 

Comparison of methods______________________________________ 87 

Minor methods of well sinking___________________________________ 88 

Boring______________________________________________________ 88 

Punching --------------------------------------------------- 91 

Driving ----------------------------------------------------·- 91 

Special operations in drilling wells________________________________ 92 

Packing----------------------------------~------------------ 93 

Cleaning ---------------------------------------------------- 97 

Screening --------------------------------------------------- 98 

Torpedoing__________________________________________________ 100 

Oil wells------------------------------------------------ 100 

Water wells--------------------------------------------- 102 

Features of well construction_________________________________________ 102 

Difficulties encountered in sinking wells___________________________ 102 

Loss of tools________________________________________________ 102 

Causes__________________________________________________ 102 

Locating lost tools_______________________________________ 103 

Recovering lost tools_____________________________________ 104 

Redrilling and enlarging _____________ ~------------------- 106 

Geologic difficulties ------------------------------------------ 107 

Spalls___________________________________________________ 107 

Bowlders ----------------------------------------------- 107 

Running muds and clays ________________ .:_________________ 108 

Quicksand_______________________________________________ 108 

Flooding of oil wells_____________________________________________ 112 

Definition --------------------------------------------------- 112 

Causes______________________________________________________ 113 

Permanent effects ------------------------------------------- 114 

State laws for prevention____________________________________ 115 

Contamination of water wells________________________________________ 117 

Usual methods of prevention_____________________________________ 117 

Examples of contamination ______________________________ ._________ 117 

Results of defective casing_______________________________________ 119 

Recomiuendations________________________________________________ 120 

Capacity of water wells_______________________________________________ 120 

Simple tests----------------------------------------------------- 120 

Tests of flowing wells____________________________________________ 121 

Storage and inflow capacity______________________________________ 123 

Effect of friction_________________________________________________ 124 

Measurement of depth_______________________________________________ 125 

Cable measurement______________________________________________ 125 

Tape n1easuren1ent_______________________________________________ 125 

Bacon double-cone method________________________________________ 126 

Deflection of drill hole_, _________ :______________________________________ 126 

Causes and results of deflection___________________________________ 126 

Instruments for measuring deflection______________________________ 127 

Cost of well sinking__________________________________________________ 129 

Supply companies --------------------------------------------------- 134 

IndeX--------------------------------------------------------------- 135 
ILLUSTRATIONS. 

Page. 

PLATE I. Standard drilling outfit, coupled for raising tools______________ 34 

II. Portable drilling machine, steam power, traction______________ 56 

III. A, Hand-power diamond drill, with friction feed; B, Steampower diamond drill, with hydraulic feed _______ .:...__________ 78 

IV. 1, Small earth auger; 2 and 3, small earth-auger bits; 4, drive 

point and screen__________________________________________ 88 

FIGURE 1. Map showing mean annual rainfall of the United States______ 10 

2. Diagram showing relation of areas of outcrop to dip_________ 12 

3. Diagram showing ordinary conditions producing artesian wells_ 15 

4. Spring-pole drilling outfit___________________________________ 27 

5. A, String of tools used with standard drilling outfit; B, Temper 

screw--------------------------------------------------- 39 

6. Drilling tools used with standard drilling outfit______________ 40 

7. Floor circles: a, Ratchet and jack; b, bar and perforated arc_ 42 

8. Standard rig arranged for spudding_________________________ 46 

9. Couplings and casing attachments___________________________ 53 

10. Percussion core drilL______________________________________ 59 

11. Canadian pole-tool outfit: a, Side elevation; b, Wrench block; 

~ Drill rod______________________________________________ 62 

12. Parts of California or "stovepipe" outfit____________________ 67 

13. Hydraulic rotary outfit; plan and elevation__________________ 72 

14. Jetting outfit______________________________________________ 77 

15. Parts of core-drilling outfit_________________________________ 80 

16. Plain core barrel-------~-----~----------------------------- 83 

17. Calyx core barrel__________________________________________ 85 

18. Well-boring tools------------------------------------------- 89 

19. Well strainers: a, Layne strainer; b, ·Cook strainer__________ 99 

20. Fishing tools used with standard drilling outfit_______________ 106 

21. Section of well illustrating a negative test___________________ 122 

22. Section of a well illustrating a partial and misleading tesL___ 122 

23. Section of a well illustrating an inverted test________________ 122 

24. Section of strata showing one correct and two erroneous tests_ 123 

25. Deflection of a diamond-drill hole in South Africa____________ 128 

6 
WELL-DRIL-LING METHODS. 

By IsAIAH BowMAN. 

INTRODUCTION. 

PURPOSE OF REPORT. 

The following report on methods of well drilling deals with a subject which should interest both the geologist and the engineer, for 

well drilling lies in that borderland where geology and engineering 

meet on equal terms. The resulting dual nature of the problems 

involved is best illustrated by the class of men who are constantly 

being called into consultation in regard to them. These men are 

either geologists who have had experience in water-supply problems, 

engineers who are somewhat familiar with geology, or men who, recognizing the special nature of the problems involved, are conversant 

with both geology and engineering. 

During the last ten years there have been many demands for a publication on well drilling, and this report is the result of an attempt to 

meet these demands. The need of such a report has been increased by 

the fact that no adequate treatment of the subject is given in any 

available American publication. There are several old English texts 

on well drilling, and a book dealing mainly with modern English 

methods has been published.a An excellent and comprehensive work 

has appeared on the conditions met and the methods used in the Baku 

oil region of Russia, on the shores of the Caspian Sea,b and there are 

a few books and reports on oil-well and gas-well construction and 

care. Scattered accounts of methods employed in certain localities 

have also appeared in engineering journals .. The trade catalogues of 

companies manufacturing the various kinds of well-si king machinery 

contain very good descriptions of their special outfi s, but no publication presents a coordinated account of the various ethods of well 

sinking and their application to wells constructed f different purposes and under different geologic conditions. 

The field studies that. form the basis of the present report w_ere undertaken in connection with ground-water investigati ns made in the 

a Isler, C., Well-boring for water, brine, and oil, 1902. 

· b Thompson, A. Beeby, The oil fields of Russia, 1904; 2d e ., 1908. 

7 
8 WELL-DRILLING METHODS. 

eastern United States. These studies extended over a period of three 

years and included actual observations of well drilling in many parts 

of the eastern half of the country, and were supplemented by one 

season's observations in the South and in the Middle West. 

METHOD OF TREATMENT. 

The driller deals with rocks as well as with tools, and to be successful he must understand the character and attitude of the rocks as 

well as the manipulation of the tools. As by far the most common 

object of well drilling is to obtain water, oil, or gas, this report deals 

with the occurrence of these products and thus meets the desire among 

drillers for information that will enable them to select well sites with 

as definite an idea as possible of the rock formations that may be encountered. The report does not, however, take up the geologic relation of ore deposits and the methods of ore prospecting with drills, 

for such a discussion would involve the whole subject of structural 

and metamorphic geology and ore deposition. 

After the oil and gas-bearing relations are discussed a short account 

of the development of well construction is given, and then the methods 

of drilling and boring are described in detail. The chief uses and 

general features of each method are discussed, the different parts of 

the outfit, its modifications, and its operation are described, and the 

more common difficulties encountered in its use are stated, together 

with the classes of material to which each method is best adapted. 

The less familiar methods as well as those commonly used are discussed, for though the unusual methods are of restricted use and, 

owing to changed economic conditions, have been superseded by other 

methods in many localities where they were formerly much employed, 

they can be successfully used in new territory where the conditions 

are similar to those that once existed in the older fields. The presentation of these now generally obsolete methods may therefore 

enable drillers in the newer parts of the country or in the island 

possessions to meet advantageously the conditions existing in those 

regions. Two specific examples may be mentioned in illustration of 

this point. Throughout central Texas, Oklahoma, and parts of Kansas 

water wells are sunk by portable churn drills operated by horsepower. 

Horsepower is now obsolete in the East, where it has been superseded 

by steam, but in the Southwest, where coal is scarce and transportation rates are high, horses are plentiful and cheap and horsepower 

is more economical than steam. From Mississippi and Alabama 

many orders come to northern and eastern supply houses for welldrilling or well-boring outfits that can be operated by hand :for sinking shallow water wells. Here, again, the reasons for retaining the 

old-style outfit are clear. In these States fuel is costly and horses 

are not plentiful, but labor is cheap, so that although the machine 
UNDERGROUND WATERS. 9 

in use is primitive, it meets the conditions better than any more 

elaborate device. 

The treatment t>f the separate methods is follow d by a discussion of a number of special features of well constru tion and a few 

general estimates of the cost of 'well sinking·. Thou h figures showing cost can be only approximate, because local co ditions are important factors in their determination, they at le st afford some 

indication of the expense of well construction or o prospect work 

by the ordinary methods of drilling and boring. 

ACKNOWLEDGMENTS. 

The preliminary discussions of rainfall, undergro nd water, and 

water-bearing formations (pp. 9-21) have been c mpiled chiefly 

from a paper by M. L. Fuller.a 

For assistance in collecting material for this rep t the writer is 

indebted to well owners, drillers, and representatives of supply companies throughout the country who have cooperated in its preparation with unfailing courtesy and good will. Indivi ual mention is 

made in the body of the report of those who have g ven special aid 

in the work .. Some of these men have taken great trouble and incurred considerable expense to procure data that are f great general 

importance though of no immediate practical benefi to themselves. 

At the end of the report is given a list of the supply companies that 

have assisted in bringing it up to date by furnishin estimates and 

descriptions and by giving permission to reproduce i lustrations and 

other copyrighted material. Any failure in the re ort to meet the 

practical needs of drillers and others interested in t e development 

of underground resources is not due to lack of inter st and support 

on the part of those who have thus cooperated with the author. 

UNDERGROUND WATERS OF THE UNITE STATES. 

AMOUNT AND DISTRIBU.TION OF RAIN ALL. 

Practically all the water encountered in well .dri ling is derived 

from rainfall. Its amount and its disposal and th conditions of 

its occurrence in the ·rocks will therefore be briefly co sidered. 

· In the eastern United States the rainfall is plenf ful, the yearly 

average varying from 20 to nearly 70 inches. (S fig. 1.) Rain 

to a depth of more than 60 inches a year falls on the Mississippi 

Delta below New Orleans, and along the Gulf c ast from near 

Mobile, Ala., to Tallahassee, Fla. A nearly equal mount falls in 

the higher mountains of western North Carolina a d eastern Tena Fuller, M. L., Underground waters ·of eastern United States : ater-Suppiy Paper 

U. S. Geol. Survey No. 114, 1905, pp. U!-40. 
10 WELL-DRILLING METHODS. 

nessee, along the coast of North Carolina, and in the Adirondack and 

White mountains. In the Gulf and South Atlantic States the rainfall is between 50 and 60 inches a year; in the New England, Central 

Atlantic, and Ohio River States, between 40 and 50 inches; in the 

upper Mississippi and Great Lake States, between 30 and 40 inches; 

and in northwestern Iowa and most of Minnesota, between 20 and 

30 inches. 

In the western part of the United States the distribution of the 

rainfall is much more irregular than ·in the eastern part. Westward 

from a line drawn through the eastern part of the Dakotas, middle 

Nebraska, western Kansas, and central Texas the rainfall decreases 

to less than 20 inches yearly, all of the Great Plains region being 

characterized by small rainfall. In the Black Hills, the Bighorn 

m1:a 20-30 

~ 30-40 

~ 40-50 

.. 50-60 

.. 60-70 

FIGURE 1.-Map showing mean annual rainfall of the United States. 

Mountains, and the higher sections of the main chains of the Rocky 

Mountains the rainfall is 20 or 30 inches yearly; and in the high 

Sierra, the Cascades, and the Coast Ranges it is 70 inches or more, 

reaching a maximum of 150 inches in the Coast Ranges of Oregon. 

In the Great Basin region, between the Sierra Nevada and the 

Wasatch Mountains, the rainfall' is less than in any other section of 

the country, in places being as low as 2 or 3 inches a year. 

DISPOSAL OF RAINFALL. 

RUN-OFF. 

- The greater part of the precipitation on· most areas is disposed of 

directly by run-off through surface streams. The direct run-off 
UNDERGROUND WATERS. 11 

· can sometimes be determined, but, owing to the inti ate relations of 

stream flow to the ground supply from which stream draw much of 

their water, it is seldom practicable to determine the n-off for large 

areas. In arid regions, where the surface deposits re porous, the 

run-off is relatively small, but, owing to the fact th t rain in these 

regions falls chiefly in sudden downpours, the annu I run-off is not 

so small as would be indicated by the small annual p cipitation. In 

humid regions and in places where the surface is c mposed of impervious materials the run-off is greater. Frozen, sn w-covered, and 

ice-covered ground yield especially large flood flow . Over frozen 

areas nearly all the rain water may at once join the s reams, whereas 

in some sandy regions practically all the precipitatio is absorbed by 

the soil. In the eastern half of the country the run-o will probably 

not average more than 20 per cent of the rainfall. In the West, 

although the percentage of run-off in small areas is a times great, it 

is on the whole less than in the East, for much of t e water that is 

not taken up directly is-later absorbed from the stre ms by the dry, 

sandy soils: -

EVAPORATION. 

Owing to the great humidity of the atmosphere during storms, 

evaporation while rain or snow is falling is small. S ow may remain 

on the ground a long time, and, as a rule, is evapora ed to a greater 

degree than rain, especially during periods of suns ine and warm 

winds that follow storms. The evaporation from di erent areas also 

differs greatly. From forest-covered soils it is relati ly small; from 

open plains it is relatively large. 

ABSORPTION. 

AMOUNT. 

The rain water that is not evaporated immediately r carried off by 

streams sinks into the ground. The ground receives he greater part 

of the rainfall, probably nearly -80 per cent in the eastern United 

States and 90 or 95 per cent in much of the West. A sorption by the 

underlying rocks takes place both directly and indire tly. Rain may 

fall on the surface of the rocks and be absorbed in thei · pores, fissures, 

and cavities, or it may be first absorbed by loose, unc nsolidated surface deposits and afterwards carried down into the ocks, or it may 

be gathered into streams that flow over rock surfaces and from these 

gradually absorbed by the underlying rocks. The am unt of rainfall 

that the rocks absorb indirectly is far greater than at which they 

absorb directly. 

Water that enters sands and gravels generally m ves toward the 

streams rather than away from them; but hi regions here the rain-
12 WELL-DRILLING METHODS. 

fall is small the gravels may absorb water from the streams which 

rise in regions of greater rainfall. 

FACTORS INFLUENCING ABSORPTION. 

Strueture.-The readiness with which water enters the underlying 

rocks is influenced largely by the structure of the rock beds or layers. 

In areas that are level or gently sloping the exposed areas of waterbearing beds that are not greatly inclined will be much greater than 

the exposed areas of beds that dip steeply and will therefore absorb a 

greater amount of water. (See fig. 2.) 

Poro8ity.-The pore space between the particles that constitute a 

rock-that is, the porosity of the rock-may in a general way be determined by the quantity of water which the rock will absorb. This 

quantity differs greatly with different kinds of rock, being least in 

compact igneous rocks and greatest in sandstones and loose sands. 

a' 

FIGURE 2.-Diagram showing relation of areas of outcrop to dip. a b, Outcrop of 

steeply dipping stratnm; a: b', outcrop of gently dipping stratum. 

The following table shows approximately the amounts of water 

absorbed by sand and by some common rocks. 

Absorptive capacity of 1·ocks in quarts of water per cubic foot.a 

Sand-------------------------------------------~------------------ 10 

Potsdam sandstone_________________________________________________ 2-6 

'l'riassic sandstone__________________________________________________ 4 

']'renton limestone ______________________________ ,..___________________ i-1-l 

Dolomite___ _______ _ ________ __ ___ _ _____ ___ _ ___ ____ ___ ___ __ __________ 1-10 

Chalk______________________________________________________________ 8 

Granite ----------------------------------------------------------- rlo-t 

Solution caverns.-In some regions water enters the ground in 

definite streams through caverns or other passages formed by the 

solution of limestone or other soluble rock. Water commonly enters 

limestone through dep~essions called sink holes, or " sinks," due to 

the falling in of the roofs or walls of caverns which have been formed 

by underground streams, or by the enlargement by solution of cracks 

or joints in the rock. These sinks maintain connection between the 

surface and the underground channels, water flowing into them and 

passing downward to become a part of the underground supply. 

Faults.-Faults are displacements along fractures that cut the rock. 

Some faults consist of single planes, with solid walls on each side, 

but many of them are formed of a number of parallel fractures, very 

a Water-Supply Paper U. S. Geol. Survey No. 114, 1905, p. 23; 
UNDERGROUND WATERS. 13 

close together, along which there has been displacemen . The rock on 

both sides of many faults is crushed and the fragme ts are mo.re or 

less disturbed with relation to one another. Som fractures are 

irregular, and the broken rock has been so moved hat projecting 

masses come opposite one another, leaving interveni g cavities into 

which water may penetrate. 

Bedding planes.-Bedding planes, separating laye s of stratified 

rock, may afford openings for underground water. The planes in 

igneous rocks along which two kinds of rock come ·n contact may 

afford similar openings. In each the movement of w ter is rendered 

easy either by the open space formed along the planes or . by the contact of porous and impervious materials or by both f these causes. 

J oints.-J oints are smooth fractures that cut the ock in various 

directions. They therefore correspond most nearly t single faults, 

but they differ from faults in that there has been pract cally no movement of the rock along them. Like faults, they pre ent conditions 

that are relatively favorable to the entrance of wate , especially at 

the intersection of two or more joints. 

In the Connecticut Valley, after a rainstorm, one ay see on the 

faces of cliffs of jointed trap rock evidences of the water-holding 

capacity of joints. These cliffs are darkened at the joi ts for hours or 

even for days after the rain has ceased by the escape f accumulated 

water, while the rest of the cliff is quickly dried und r the action of 

the sun and wind and presents its usual appearance. 

Cleavage planes.-Cleavage consists of minor fra tures that cut 

the rock. Unlike joints, cleavage planes usually r n in only one 

direction, and are frequently not actual fractures, b t simply lines 

of weakness, along which the rock tends to split. leavage is best 

developed in fine-grained co~pact rocks, of which ro fing slate is a 

good example. Cleavage planes do not afford as rea y passage for 

water as do the other structures described. 

Foliation and schistosUy.-Foliation and schistosit are due to the 

presence in rock of minerals that occur in thin, pl te-like crystals 

that lie parallel to one another. In many places wate passes readily 

into the rock along planes formed by layers of these c ·ystals. 

AMOUNT OF UNDERGROUND WATER 

·A part of the underground water which has rea hed the lower 

levels occupies spaces along bedding, fault, joint, an other planes, 

and a part occupies solution channels and caverns fo med in soluble 

rock. The several kinds of fractures mentioned, although very 

numerous in the aggregate, nevertheless comprise on y a small portion of the open space within rock. The pores betwe n the particles 

that make up the rock are, on the contrary, ever where present 

throughout the entire mass and constitute by far the largest part of 
14 WELL-DRILLING METHODS. 

the open space within it. The pore space thus affords the best 

reservoir for the storage of water. 

In most places it is necessary to penetrate some distance below the 

earth's surface in order to reach a zone saturated with water, the 

actual depth depending on the amount of precipitatiQiJ1, the character 

of the rock, and the topography. 

This depth is least in regions of much rainfall and greatest in arid 

regions; and in general it is least in valley bottoms and ·greatest in 

the higher lands. In some localities, as at springs and in marshy 

lands, the plane of saturation coincides with the surface, but the 

existence of ground water at the surface is· due to exceptional 

conditions. 

The lower limit of penetration of water depends on a number of 

conditions. The limit to which water will penetrate is the depth at 

which the weight of the overlying rock becomes so great that pores 

between the particles can not exist. This depth has been theoretically 

placed at about 6 miles. Practical experience in well drilling, however, does not approve the assumption that all rocks are satttrated 

below a moderate depth. In the Pennsylvania and the New York oil 

regions, for instance, rocks that are practically destitute of water are 

encountered at a depth of only a few hundred feet. These rocks include coarse-grained sandstones capable of holding large amounts of 

water, yet as far as can be determined they are quite -dry, so that 

it is necessary in some wells to pour in from the top the water required in drilling. In some parts of these oil fields the drill enters 

rocks containing salt water after passing through these water-free 

rocks; but very rarely is fresh water found below the dry rocks. In 

some places wells have been drilled several thousand feet. deep without encountering water below the first few hundred feet; but, although 

the rocks thus penetrated are far from being saturated, they doubtless 

hold slight amounts of moisture. These facts show the fallacy of the 

popular idea that there is plenty of water if one only goes deep 

enough, and that great underground lakes exist. 

Although the depth to which water penetrates in large quantity 

is much less than is frequently assumed, the ground contains, nevertheless, an enormous amount of water.· ltfany estimates of the 

an10unt of ground water have been made, all of which take into 

account only the free water (that which is or might be available 

for pumping purposes) and do not include that which is contained 

in moist clays and other materials and is not readily yielded to 

wells. These estimates have become more and more moderate, ranging from tha-t of Delesse, made about 1860, which showed a layer 

sufficient to cover the surface of the globe 7,500 feet deep, through 

that of Slichter ( 1902) which showed a similar layer 3,000 to 3,500 

feet deep, and of Chamberlin and Salisbury (1904) which gave a 
UNDERGROUND WATERS. 

layer of 800 to 1,600 feet thick, to that of Fuller a 

shows that. the amount of water available in the 

sufficient to form a layer over the surface of the glo 

than 100 feet deep. ·This amount is equivalent- to a 

of the volume of oceanic water. 

ARTESIAN CONDITIONS. 

The requisite conditions for artesian water are 

than is usually supposed, and some artesian flows a 

circumstances which are considered anomalous. The 

artesian flow are clearly stated by V eatch,b who says: 

15 

1906), which 

rth's crust is 

a little less 

rto part 

Underground water in passing downward may go beneath a elatively i:rnpervious layer which tends to confine it and produce a hydrauli head. In this 

respect underground waters differ from surface waters, w ich are always 

free on one side and can not, except where artificially confin , as by closed 

flumes, produce analogous phenomena. This natural confineme t of the ground 

water causes water in wells to· stand above the porous laye in which it is 

FIGURE 3.-Diagram showing ordinary conditions producing artesian ells. A, Artesian 

wells ; B, head of water if there be no loss by resistance and leakin ; C, actual head 

or hydraulic gradient; D, ground-water table at outcrop. 

encountered and is of vast economic importance, especially 

where the water is very deep seated and has been transferred 

more bountiful rainfall. 

In order that a well may flow it is necessary that the followi g conditions be 

satisfied: 

1. There should be sufficient rainfall. 

2. There should be relatively porous beds ·suitably expose 

transmit the water. 

3. There should be less porous or relatively impervious layer so placed that 

they may confine the water collected. 

4. The level of the ground water at the source should be at a 

above the mouth of the well to compensate for the loss of head ue to resistance 

and leakage. 

The arrangement of the factors which produce a flow is by no eans constant. 

These factors vary considerably from point to point, and relative y new combinations are to be constantly expected. Probably the commonest co bination is that 

shown in the accompanying diagram [fig. 3]. Here the confini g beds are clay 

a Fuller, M. L., Total amount of free water in the earth's crust: W ter-Supply Paper 

U. S. Geol. Survey No. 160, 1906, pp. 59-72. 

b Veatch, A. C., and others, Underground water resources of Long I land, New York: 

Prof. Paper U. S. Geol. Survey No. 44, 1906, pp. 54-55. 
16 WELL-DRILLING METHODS. 

and the parous bed is a sand which dips regularly in the direction in which 

the surface slopes. Water falling in the region marked" catchment area" sinks 

into the sands and supplies the artesian wells on lower ground. 

The foregoing conditions may be taken as typical of a large class of 

artesian wells and are perhaps those more commonly described and 

understood, but flows may be obtained under several modifications of 

the conditions described, though they depend on the same general 

principles. 

W A.TER-BEA.RING FORMATIONS. 

GEOLOGIC CONSIDERATIONS. 

Geologic knowledge has perhaps no greater practical value than 

in the study of the occurrence of underground water and in the selection of sites for drilled wells. In many places the selection of the 

location for a well is so restricted that there is practically no choice 

at all. Yet, though water supplies for public buildings and institutions are usually required on the premises, it may often happen 

that if the site had been shifted a :few yards water would have been 

reached at much less depth; or if it had been moved down the dip of 

the strata a short distance flowing water would have been tapped and 

pumping would have been avoided. 

The locating of wells is subject to so much superstition and guesswork among drillers and prospective well owners that it seems worth 

while to point ovt a few general principles that should control. 

Many of the details that influence the presence of underground · 

water can be intelligently determined only by means of an examination of the region in which the well is to be sunk and a careful 

analysis of observations of other wells put down in the locality. The 

observing well driller will :furthermore take into account the surface 

drainage of the region, the presence or absence of forest lands which 

may influence the rate and amount of run-off, the existence of springs 

as evidence of surplus water at given points, and the depth and 

character of soil overlying the rock. Especially will he consider the 

structure of the soil cover, for it may be water-laid and therefore 

stratified and regular in its formation, so that an accurate and quick 

deduction can be made as to the depth and availability of the ground:-

water supplies; or it may be wind-laid and therefore less regular; or, 

in regions covered with material deposited by ice it may be still more 

irregular. All ground water, however, has a more or less intimate 

relation to the surface drainage and the topography. 

Even after the most thorough investigation of the surface geology, 

however, there is always a certain degree of chance in the results of 

the first well drilled in a region. The variations from conditions 

predicted nre, as a rule, small, or even insignificant, but occasionally 

they are great, as the projectors of the Simplon tunnel discovered 
WATER-BEARING FORMATIONS. 17 

when they encountered unexpected volumes of heated ater. Therefore the conclusions .of a competent geologist are to b considered by 

the well driller as a moderately sa:fe guide in a n w region, one 

which will enable him to determine roughly the possib lity of obtaining water, the method of drilling to be employed, and he length anrl 

kind of casing that will be required. More reliable eologic inferences, however, can be drawn only after some drilling has been done 

in the region; so that the geologist and the driller m st supplement 

each other. 

CLASSES OF MATERIAL. 

SANDS AND GRAVELS. 

Beds of sand and gravel are very porous, as much as 30 per cent of 

the volume of some of them being made up of free spac , so that saturated layers that are penetrated by wells yield copio s supplies of 

water. This water is in most places of good quality, bu in some wells 

it is greatly mineralized with salts derived from the mo e soluble rock 

fragments that constitute the deposits. 

In passing downward through sands, especially the ner varieties, 

surface water may be naturally filtered so that su stances with 

which it may have been polluted are removed. In coarse sands 

and in gravels the water passes downward more rapidl and the conditions are less favorable for its filtration, so that i may remain· 

polluted. In general, however, water derived from san sand gravels 

that lie a considerable distance below the surface is pur . 

Because of the readiness with which sands and grav Is yield their 

water, wells that are sunk close together in them ay affect one 

another, the deeper wells, or those which derive their su ply from the 

sands at the lowest points, drawing the water from he shallower 

wells. The readiness with which the water moves is al o the cause of 

important fluctuations in the level of the surface of the saturated 

zone, as the water level may fall rapidly after wet sea ons. To procure permanent supplies a well should penetrate belo the level to 

which the water surface falls in the driest season. 

CLAY. 

Pure clay is nearly imper~·ious to water and contains little or none 

that can be utilized as a source of supply. Water is frequently 

reported in clay, but as a rule it comes from more r less sandy 

layers within a clay bed. In some places sand that ap roaches clay 

in fineness and that is sometimes mistaken for clay yield considerable 

amounts of water. Clay is of great importance in co nection with 

underground water, not directly as a water-bearer, but sa confining 

layer to porous sands from which it prevents the water f om escaping. 

65275°-W s P 257-11--2 
18 WELL-DRILLING METHODS. 

Because of the fineness of clay the water it contains comes into 

contact with a relatively large amount of mineral matter and may 

become mineralized, especially by lime and salt, but as a rule it is 

free from contamination by the organic substances that cause typhoid 

fever and other diseases. 

· When it is necessary to obtain water from clay the well should be 

as large as practicable and should be carried deep enough to provide 

ample storage capacity, for clay yields only a small amount of water, 

and that very slowly. Dug wells are usually most satisfactory where 

clay is near the surface, but should be carefully covered and protected 

from pollution. 

TILL. 

Till is a heterogeneous mixture of clay, sand~ gravel, and bowlders. 

In texture it ranges from very pervious to impervious, according 

to its content of sand or of clay. In few places is it definitely bedded. 

"\Vater generally occurs in it in minute, more or less tubular, channels, 

but occasionally is distributed through interstratified sandy beds. In 

the finer, more loamy phases the supply is not abundant, but the 

coarser portions of the material furnish water more plentifully. 

In the aggregate, till yields a large amount of water, and where 

it is sufficiently thick it forms a most convenient and accessible source 

of supply, but because its material is so irregularly di"sposed the success of the wells varies greatly. Water is usually found in it close to 

the surface, but better water can be obtained by casing off these upper 

. water-bearing beds and extending the wells to greater depth. In general, wells of large diameter, similar to those dug in clay, are most 

satisfactory, for the surface of the till exposed inside the well-that 

is, the surface from which water can enter the well-is much greater 

than that exposed in a bored well, and the larger wells also have 

greater storage capacities. Dug wells may therefore utilize small supplies which would be insufficient for bored wells. 

The water of till is generally uncontaminated, because in its downward passage through the clay, of which till is in part composed, it 

is subjected to thorough filtration. If the water does become polluted, 

however, it may retain its dangerous character for a long time and 

for considerable distances. 

Till is widely distributed over the northeastern and north-central 

parts of the United States in the great areas covered by glacial drift. 

The southern border of the glacial deposits extends from Marthas 

Vineyard, in Massachusetts, through Long Island and northern New 

Jersey, across northern Pennsylvania into the ;southwestern part of 

New York. Thence it turns southwestward across Pennsylvania and 

Ohio, soutP.ern Indiana, Illinois, and central Missouri, and then 

swings northwestward into Canada. 
WATER-BEARING FORMATIONS. 19 

SANDSTONE, CONGWMERATE, AND QUARTZ! • 

Sandstone is, on the whole, the best water beare the solid 

rocks. Under the most favorable conditions it is sat rated throughout its extent below the ground-water level and yiel s water freely 

wherever it is struck by the drill, although some of t e fine-grained 

sandstones yield it less readily. Water derived fro sandstone is 

of better average quaijty than that obtained from any other material 

except sand and gravel. It is seldom polluted, and the wells supplying it can generally be safely used if they are cas d to keep out 

surface water. Wells obtaining water from sandsto e are usually 

drilled, although where the sandstone is very near t e surface dug 

wells are common. 

In the Appalachian Plateau-the ar~a comprising the bluegrass 

district of l{entucky, the Nashville basin of Tennessee, and the Cumberland and other plateaus of Tennessee, 'Vest Vir inia, western 

Pennsylvania, and New Y ark-sandstone is perhaps t e chief of the 

water-bearing sedimentary rocks. Where sandstone be s are exposed 

along ravines springs issue from them, and these s rings are the 

source of supply for a large number of the inhabitants . 

Porous sandstones also underlie the great plains o the Dakotas, 

Kansas, and Nebraska, and yield artesian flows throng out an extensive area. Over much of the region that lies farther s uth they also 

furnish abundant underground water. 

In some places conglomerate yields considerable w ter, although 

as a rule its absorptive capacity is not so great as tha of sandstone, 

and it is not so widely distributed. 

Quartzite is a metamorphosed sandstone, the space between the 

grains being filled by hard, siliceous matter. Because of this filling 

of the pores there is little chance for water to enter t e rock, hence 

it is not commonly an important source of water. 

Old sandstones, shales, and other sedimentary rocks hat have been 

altered to quartzites or slates lie near the surface in th Appalachian 

Mountains, the Ozark and-Superior highlands, and the Rocky Mountains, and on the borders o:f these higher lands yield so e water, but 

generally both the occurrence and· quality of such ater are uncertain. · 

SHALE. 

Shale, like clay, is a poor water bearer, but may yie d water from 

bedding, joint, and cleavage planes, and other crevice . It is most 

important, however, as a. confining layer to prevent he escape of 

water from porous sandstone that may be interbedded ith it. The 

water in shale is reached by deep wells and is gen ,ra1ly uncontaminated by the bacteria of disease, though it may be alty or bitter 

or otherwise undesirable. 
20 WELL-DRILLING METHODS. 

Lll\IESTONE. 

The water of limestone occurs mainly in open channels and caverns 

which have been formed by the solvent action of water passing along 

joint or bedding planes. These caverns and water channels are very 

irregularly distributed and their location can seldom be determined 

by examining the surface, but most deep wells in limestone regions 

encounter one or more such passages at relatively slight depth. Adjacent wells sunk in limestone, even if only a few feet apart, may obtain 

very different results, as a difference of a foot or two in position niay 

n1ean missing a water channel. The water of limestone regions contains dissolved calcium carbonate (commonly called carbonate of 

lime) which makes it hard, but usually it is not otherwise heavily 

mineralized. It is, however, likely to be polluted owing to the fact 

that much of the water of the underground streams in limestone has 

found its way downward through sink holes and carries with it more 

or less surface wash. 

water-bearing limestones occur in the southern and southeastern 

portions of the United States and also in the Appalachian Mountains, but owing to the poor quality of the water, recourse is usually 

had to springs or to wells sunk in other rocks. 

GRANITE, GNEISS, AND SCHIST. 

Granite and gneiss are very dense and have very small pore spaces, 

and therefore hold but little water. Schist may contain considerable 

water that has penetrated along foliation planes and is held by the 

rock, but it gives up water very slowly and is not important as a source 

of supply. The joints in these rocks yield the largest amounts. Joints 

are most common near the surface and diminish in number and 

definiteness with increase in depth. For this reason most wells in 

crystalline rocks obtain water, if at all, within 200 or 300 feet of the 

surface, and it is generally useless to go deeper than 500 feet, although 

in some places, as at Atlanta, Ga., water supplies have been obtained 

:from them at depths as great as 1,600 feet. 

The joints in crystalline rocks usually forq1 complex systems of 

intersecting planes, and polluted water may pass in a zigzag course 

from the surface downward along the joints until finally it reaches the 

well at a depth of many hundred feet. 

Varieties of the older crystalline rocks outcrop or lie near the 

sur:face over the Piedmont area along the eastern front of the Appalachian Mountains, along the Sierra Nevada, and in parts of the 

Cascade and other ranges of the Pacific coast. In the inhabited districts in these areas some water is obtained from shallow wells sunk 

into the upper, decayed ·portion of these rocks, but where surface 

water is available streams and springs are used for domestic supplies. 
OIL AND GAS BEARING FORMATIONS. 21 

LAKE AND STREAM DEPOSITS. 

Along the northern portion of the Atlantic coastal lain there are 

extensive lake and stream deposits of clay, sand, and gravel, which 

are largely drawn upon for domestic water supply. This water is 

usually plentiful and good. 

In the lower Mississippi Valley the fine silts vf he flood~plain 

deposits are saturated with water a short distance bel w the surface 

and furnish abundant supplies to small wells. The c ief drawback 

to shallow wells in this material is the unusually sma I mesh of the 

screens that are necessary to exclude the fine sand from the wells. In 

most places, however, a lens of coarser sand or gravel an be located, 

and this can be drawn on for water supply without dan er of clogging 

the screen. 

In many parts of the arid region of the western Unit d States there 

are great basins or valleys which are deeply filled ith sediments 

brought down by streams and deposited in former 1 kes. In some 

places these unconsolidated sands and silts contain w ter at shallow 

depths, and they form the chief source of supply throu hout much of 

the Great Basin region of Utah, Nevada, southeaster Oregon, aud 

southeastern California. In the more favorably sit ated of these 

desert Yalleys, notably in the Coachella Valley, in sout eastern California, the deeper water of the unconsolidated deposits may be under 

sufficient artesian head to yield flowing wells. 

In the great central valley of California and in the coastal slopes 

of the Pacific States there are also deep alluvial depos ts that are of 

great importance as sources of underground water. Those of the 

coastal plaip. of southern California have been extensi ely tapped to 

obtain water for irrigation, and water is also drawn from similar 

deposits around Puget Sound. 

Many smaller deposits of alluvial mat~rial at the 

western mountain ranges also yield valuable supplie of water to 

shallow wells. 

OIL .AND G.AS BEARING FORM.ATIO 

STRUCTURE AND CHARACTER. 

Oil .and gas occur under conditions that here need but brief description. As a rule they are associated with the rock str ctures called 

anticlines-upward, archljke folds of the rocks--along the flanks or 

in the highest portions of which oil and gas collect. here both are 

present the gas overlies the oil, which in turn lies upon ater-bearing 

beds. The presence of underlying water is usually con idered necessary to the collection of oil, as because of its lesser s ecific gravity 

the oil rises above the water, is forced intq the highes parts of the 

! 
22 WELL-DRILLING METHODS. 

folds, and is held there by the overlying impervious rocks and the 

underlying water. Anticlinal folding, however, is not an absolutely 

essential feature, for it is not found in all oil fields. 

Oil and gas occur almost entirely in sedimentary rocks (shales and 

sandstones), and their origin is very generally ascribed to the slow 

decomposition and distillation of organic matter. Rarely are they 

found to penetrate from sedimentary into igneous or plutonic rocks. 

DISTRIBUTION. 

Since the discovery of petroleum in commercial quantities in Pennsylvania the development of the oil fields of the United States has 

progressed rapidly, and the present oil and gas production of the 

TJnited States is greater than that of any other country. 

Oil and gas are found in the Appalachian field at depths ranging 

:from 400 to 3,000 feet, and are drawn from several horizons. The 

reservoirs are made up of layers of porous sandstone which are separated by shaly beds. 'Vithin the sandstone layers the oil has accumulated in "pools," presumably under the influence of gravity. 

The many beds of sandstone form a series of rocks about 2,000 

feet thick, deposited during the Devonian and Carboniferous periods 

of geologic time. Near the western margin of the Appalachian field 

the oil and gas bearing beds dip gently southward or southeastward, 

so that the oil-bearing sandstones are carried farther beneath the 

surface. In 'Vest Virginia oil is obtained from wells between 3,000 

and 4,000 feet deep. 

In that part of the Pennsylvania field which lies within the Appalachian zone of folding, gas and oil are in places found only within 

the area of the folds. As the gas, on account of its lower specific 

gravity, lies above the oil, in some localities it is possible to drill 

wells on the flanks of a fold and reach the oil directly without 

1neeting the gas. 

In western Ohio and Indiana oil is produced from the Trenton 

limestone, a rock different from that found in the Pennsylvania 

field. The original productive Ohio field has been developed until 

it now extends across Indiana and into Illinois. The wells of this 

field range in depth from 100 to 1,400 feet. In eastern Illinois oil 

is obtained at depths ranging fron1. 400 to 600 feet from soft and 

very porous limestone lying beneath beds of shale. 

In the oil fields of southeastern Kansas and adjacent parts of 

Oklahoma the oil and g~s reservoirs are in sandstone interbedded 

with shale.a As the outcrops of some of the sandstone beds may 

be traced into shale, and as the records of wells short distances a part 

differ greatly, it seems probable that the sandstone beds form lenses 

a Adams, George I., and others, Economic geology of the lola quadrangle, Kansas; 

Bull. U. S. Geol. Survey No. 238, 1904, p. 25. 
HISTORY OF WELL DRILLING. 23 

whose position and exten.! can not be predicted, exce t within wide 

limits. The beds also vary exceedingly in their con ent of oil and · 

gas. The depth of the productive beds increases so thward, being 

400 to 700 feet in Kansas and more than 1,000 feet i the Osage and 

Cherokee Nations, Oklahoma. 

The Gulf oil fields, which were opened in 1891 by 

gusher at Beaumont, Tex., and have been extended i 

other localities in Texas and in Louisiana, are pecu iar in that the 

oil and gas occur chiefly in unconsolidated sands t at lie between 

capping layers of clay, though they are found also ·n this field in 

sandstone and in porous limeston~. The petroleum t Beaumont is 

produced from a l~ose, honey-combed rock, lying 1,0 0 to 1,200 feet 

below the surface. 

In California oil is found in friable sandstone and hale which are 

of much more recent geologic age than the product ve beds of the 

eastern fields. Some wells reach depths of 4,000 fee or more. On 

account of the structure and location of the produci g beds some of 

the wells near the coast are sunk through the shallow ater off shore, 

and near Santa Barbara the oil derricks are erected o long piers and 

built out into the surf. 

In Alaska petroleum fields are being explored on tl e west shore of 

Cook Inlet, at Cold Bay on the Alaska Peninsula, an near Controller Bay. The oil in these fields is found in sandy shal whose history 

is involved with that of overlying or intrusive beds. he structure is 

complex and developments are yet too meager to ermit accurate 

determination of either the extent or character of the productive 

beds. 

Oil in small quantities is found in several States o 

fields, notably in Michigan, Colorado, Utah, and 

vVyoming the indications give promise of the futur 

large quantities of petroleum. 

HISTORY OF WELL DRILLING. 

ASIA. 

tside the great 

yom1ng. In 

production of 

In the dry regions of Asia the climate, the un versal scarcity 

of water, the locally. dense population, and the dom nance of agriculture resulted in an early development of the art f constructing 

wells. It is not surprising that in China, a country p olific in inventions that are in modern use, there should have bee devised, centuries ago, for well drilling, a churn drill which in rinciple is like 

the churn drill used to-day. It is also to the early C inese engineers 

that we are indebted for one of. the few known met ods of sinking 

wells through loose soil. and ·quicksand to great dep hs; that is, by 

constructing a curb of stone or brick, which settles as the excavation 
24 WELL-DRILLING METHODS. 

is deepened and th~reby reduces the pressure of the surrounding 

material. The ancient writings of the Chinese contain occasional 

references to well-drilling machines, and to the Chinese also belongs 

the credit of reducing well drilling to a science. The Chinese, however, though led, naturally enough, to the invention of means of well 

drilling, especially in the more arid parts of their country, on the 

boundaries of the great desert of Gobi, reached only a very primitive 

stage in the mechanical part of the work, and they have made slight 

improvement in their machinery during the last century, which has 

witnessed such remarkable mechanical development in the United 

States. • 

In western China, near the borders of Thibet, a method of drilling 

for petroleum in use at the present day illustrates the primitive 

though scientific manner of well construction in that country. The 

drilling tool is of the free-falling kind, a hard-wood rod or lifter 

having an iron cap at each end serving as the hammer or maul. This 

is fastened to the top of an iron link and falls on the_ chisel or bit 

attached to the bottom of the link. (This device is the earliest form 

of the Canadian pole-tool apparatus used in this country, but as employed in America the wooden rods are used not as a maul but merely 

as a lifter.) The wear on the parts of the string of tools thus coming into violent contact is very great and necessitates their frequent 

renewal. The tools are lifted and dropped by mean~ of a windlass 

having an automatic release. The drill has a narrow horizontal cutting edge by which the rock is spalled off and pounded into bits 

which may be removed with a sand bucket. The cable is made of 

hvisted strands of rattan. With this outfit a great expenditure of 

time and labor may be required to produce meager results, and yet 

by its use wells have been drilled to a depth of 3,600 feet. 

EUROPE. 

The science of deep-well drilling received great impetus through 

experience gained in drilling the Passy well of Paris, completed in 

1857, which was curbed to a depth of 1,923 feet. Its diameter was 

2! feet and it delivered 5,588,000 gallons of water daily to a height 

of 54 feet above the surface. Even more remarkable than this is the 

mammoth well at La Chapelle, which has a diameter of 5! feet and 

extends to a depth of more than 1,000 feet. The drill used in con.,. 

structing this well weighed 4 tons and was operated by a powerful 

steam engine that caused it to strike 20 blows a minute. 

The artesian well at Grenelle, near Paris, completed in 1841, was 

for many years the deepest weH in the world. The history of the 

seven years of incessant labor expended in its construction has been 

equalled in interest by that of very few other engineering enterprises. 
HISTORY OF WELL DRILLING. 25 

It was in drilling this well that workmen first learn .d the requirements of deep drilling and first exercised their ingen ity in recovering broken parts of the drill and rods. A final dept of 1,798 feet 

was reached, drilling being stopped in a large ca vi y from which 

water having a temperature of 82° F. rose with gre t force to the 

surface, forming a large flowing artesian well " a parabolic 

fountain " many feet in height. 

The successful completion. of these deep wells in 

lowed by deep borings iri England and Germany. 

were of great dimensions and for the first time gave t 

idea of the underground structure of the rocks, nearly 

society having investigated the drilling operation 

another point of view. 

UNITED STATES. 

EARLY DRILLING. 

ranee was folany of these 

e geologist an 

very scientific 

from one or 

Drilled and bored wells for water supply have lar ely superseded 

dug wells in many parts of the United States, because ater obtained 

from the deeper sources that are tapped by drilled we Is is less likely 

to be contaminated than that obtained near the su face, and the 

supply of these deeper wells is also usually more con tant than that 

of shallow dug wells. 

The methods of drilling water wells have been gr atly improved 

during recent years by experience gained in sinking o great depths 

for oil and gas, such drilling having resulted in the evelopment of 

smaller and more efficient tools. 

Contemporaneous w·ith the development of the art f deep boring 

in Europe, deep wells were first put down in the U ited States at 

Charleston, S. C., at Louisville, l{y., and at St. Loui , Mo. In the 

Pennsylvania oil fields wells 2,000 to 4,000 feet deep .w re drilled, the 

first deep well in the celebrated Oil Creek region, acco ding to a published account of the early development of the field ,a having been 

drilled by Jonathan Watson in 1866 to a depth of 2, 30 feet. With 

the discovery of oil the well-drilling business became ontinuous and 

profitable and soon attracted the attention of enginee s whose ingenuity was taxed to the utmost by its obstacles and mis aps. At present it engages the interest of some of the most expe t engineers in 

the country, for, with the extension of artesian-water evelopment to 

nearly all parts of the world, drillers have encountered nearly every 

variety of geologic formation, and therefore nearly every kind of 

difficulty and mishap. 

Tubular wells lined with iron pipe or casing supe seded wells of 

larger diameter lined with wooden curbing .or cond ctor pipe. In 

a McLaurin, J. J., Sketches in crude oil. 
26 WELL-DRILLING METHODS. 

the central and western States tubular wells were not commonly used 

until1875, but along the Atlantic coast they were drilled much earlier. 

As early as 1849 tubular wells were drilled with machinery and tools 

designed by JesseN. Bolles and a Mr. Knight. 

DRIVEN WELLS. 

In localities where a pointed pipe can ~e driven easily to the water 

level many wells known as "drive" or "driven" wells were put 

down between 1865 and 1885, and a few such wells are still sunk. 

Some of these wells are made by pointing the end of a piece of iron 

pipe, drilling small holes near the pointed part, and driving this pipe 

into the earth with a sledge or drop hammer. Other sections of pipe 

are screwed on as the well is driven deeper. In some wells pointed 

screens made in various ways are attached to the bottom of the pipe 

thus driven. These screens prevent coarse sand from entering the 

pipe and wearing out the pipe valves, but many wells of this kind are 

short lived, and in some localities tubular wells of larger diameter, 

made by other methods, have taken their place. 

Driven wells can not be put down in rock and many difficulties are 

Inet in sinking them. In order that they may be successful, it is necessary that the perforated end of the pipe be driven into a good waterbearing stratum in sand or gravel within 30 .feet of the surface and 

there stopped. A patent was granted on the drive well to a Mr. Green 

after the civil war, but drive wells had been put down as early as 

1861. 

WELL AUGERS. 

The method of boring wells by turning an auger into the earth was 

in common use throughout the country between 1865 and 1885 and is 

still employed in some sections. One of the first augers used for this 

purpose was made by J. J. ,V. Adams in Virginia in 1855 and is 

now in the possession of George D. Loomis, of Tiffin, Ohio, from 

whom many historical data were obtained. 

Well augers, ranging in diameter from 2 to 4 inches, were much 

used through the Central and Western States during their settlement, 

and in some parts of the country they are still used, though in most 

places the open bored well, lined with wooden plank or with sewer 

pipe, has been superseded by the tubular well made by sinking a 

wrought-iron pipe into the earth. 

JETTING METHOD. 

A jetting outfit for use in sinking wells in unconsolidated deposits 

was built in 1884 by W. C. Wells, who did much to demonstrate its 

utility. In using this device the material is loosened by a strong 
HISTORY OF WELL DRILLING. 27 

current of water directed through a suitable nozzle o bit and is carried to the surface and thus removed by the return s ream of water. 

Where it can be used, it is a very rapid, efficient, and heap means of 

sinking wells. 

SELF-CLEANING METHOD. 

Machinery and tools for drilling tubular wells h what is now 

known as the " self -cleaning " method were construe d and used in 

1857 or shortly before by Jesse N. Bolles. This metho is often called 

"hydraulic," but the material is loosened and broken up by the percussion of a drill bit. Water, however, provides c ntinuous selfcleaning of the hole, for by the action of the drill t e loosened material is pumped up through the hollow drill rods a d delivered at 

the surface. 

Following Mr. Bolles in the use of tools of this k nd came Jesse 

Button, a well driller and inventor. Soon after t e discovery of 

oil in northwestern Pennsylvania Mr. Button did 

much drilling with a machine especially constructed 

for the use of the selfcleaning tools, and aided 

greatly in making this 

method. of drilling efficient. 

SPRING-POLE OR CHURN 

DRILL. 

The first churn drill employed in the United States 

was a crudely constructed device (fig. 4) consisting of a small tree or 

spring pole, sufficiently strong to bear the weight of rope and drill, 

supported in a forked upright and securely fastene down at the 

larger end or weighted so as to counterbalance -the rill. -The pole 

was inclined over the hole at an angle of 15° to 30° or more from the 

horizontal, so that the tools ~ould be raised and lowe ed in the well. 

The tools, which were generally made by local blacks iths, consisted 

of solid wooden rods, seven-eighths inch to 1! inch s in diameter, 

fitted with box-and-pin joints and attached to the s ring pole by a 

rope or chain. The cutting instrument was a steel chisel or drill 

welded to an iron stem a few feet long and attached t the lower end 

of the line of rods. Cross handles were bolted to t e rods, which 

were supported by a swivel, and by these the drill wa slowly turned 

during the drilling. The derrick consisted of three ti hers, 20 to 30 

feet or more in height, bolted together at the top; the joint was 

strengthened by an iron circle slipped over the timber . 
28 WELL-DRILLING METHODS. 

The machine was operated by two to four men, who ~y their weight 

brought the pole down quickly, so that the drill would strike a blow 

on the bottom of the hole. It was then lifted again by the spring of 

the pole. When it became necessary to pump out the accumulated 

drillings the tools were raised by means of a rope passed through a 

pulley at the head of the derrick and carried to a windlass supported 

on a crank shaft between two of the legs. After the hole had been 

cleaned, the tools were lowered by the same device. In raising the 

drill the different sections were unscrewed piece by piece as they 

came up, and they were screwed together again when the drill was 

lowered. A clip on the end of the rope from the windlass could be 

inserted in the swivel at the upper end of the string of tools, thus 

enabling the driller to suspend the tools temporarily when the deepening of the hole necessitated lengthening the rope or chain fastened 

to the spring pole. The sand pump was a long tube, 3 inches in 

diameter, with a hinged bottom opening inward and a piston valve 

working on a sliding rod, somewhat in the manner of a syringe. It 

was lowered to the bottom, and when the poles, which were attached 

to the sliding rod of the pump, were raised quickly the drillings were 

sucked into the pump by the sliding valve, retained by the bottom 

valve, and thus pumped out. 

Sometimes the tools were operated by a number of men perched on 

a scaffold built about the well. The spring of the pole would lift the 

tools for the blow and the ~eight of the men bring them down. The 

work was extremely laborious, the speed attained being about 2 feet a 

day :for each man stationed on the scaffold. The men had to rest every 

few minutes, and if it was desired to drill continuously it was neces-

:sary to supply double sets of men, who relieved each other after a few 

minutes' work. The method was often called " kicking down a well," 

and was employed in sinking hundred of shallow wells. It afforded 

men of limited means a way of obtaining a water supply, but was 

inadequate for deep-well drilling, and has become nearly obsolete. In 

drilling hard material progress was extremely slow ; the force of the 

blow decreased as soon as a few inch~s had been drilled, for the drill 

must recut the drillings, so that the tools had to be hoisted out and the 

hole sand-pumped frequently. · 

The wells sunk by this process were as a rule not more than 4 inches 

in diameter and were comparatively shallow, for their depth was 

determined by the elasticity or counterweight of the pole and the 

ability of the operators to raise the tools out of the well when it 

became necessary to remove the drillings. . However, some of them 

exceeded 300 feet in depth. 

STANDARD METHOD. 

The sinking of deep water wells and of deep borings for gas and 

oil made necessary the use of heavier tools, differing from those of 
HISTORY OF W LL DRILLING. 29 

the spring-pole outfit. The first st p in the evolutio of the spring 

pole into the standard method wa the substitution of horse power 

for manual labor in working the t ols. The next i provement was 

the replacement of the spring pole y the walking bea , whose motion 

depends not on elasticity but on p wer transmitted rom an engine 

through a jack wheel and crank haft. The first il well drilled 

by steam power was put down op ., in 1860. 

The most important implements are the "jars," 

which were long ago invented b William Morris They consi~t 

of two linked pieces of steel of ood quality, hav ng an endwise 

motion, or slack, of 6 to 9 inches. They enable th delivery of a 

quick, hard, upward blow, which ars the tools free when the drill 

is working in caving or creviced aterial. For "fi hing" for lost 

tools they are made longer to ena le a harder blow o be delivered. 

Their invention made possible th drilling of 1nu h deeper holes 

than had before been attempted, or the driller k ew that if the 

tools became stuck he need not de end on mere stre gth of rope in 

withdrawing them. A quick upw rd stroke with go d, heavy, wellmade jars will exert a greater for e on the drill tha a steady pull 

of several tons. It is reported t at George Smith of Rouseville, 

forged the first steel-lined jars i 1866, for H. Le Nelson,a who 

also in that year adopted the " leasantville rig," discarding the 

" grasshopper." In the former the walking beam is fastened in the 

center to the" samson post," with o e end attached t the rods in the 

·well and the other to the band-whe l crank. 

Many improvements on pumpin rigs, dr.illing too s, and gas rigs 

were patented by George Koch, of ast Sandy, Pa. line to control 

the engine from the derrick was fi st used by Samu Taft, in 1867, 

in drilling a well near McClintock ille; and a device to regulate the 

motion of the engine by means of rod from the der ick attached to 

the throttle valve of the engine as first used by enry Webber, 

who drilled a 600-foot well near S oky City in 1863. Webber also, 

perhaps for the first time, dresse the tools in a f rge under the 

derrick. 

To exclude surface water a leat er " seeg bag," 

seed, was tied firmly around· the p mp tubing and et down to the 

proper depth. In a few hours the seed swelled and filled the space 

between the tubing and the wall of the well and endered it impervious to the passage of water. 

Drilling " wet holes " was slow and uncertain, as the tools were 

likely to break, and whether or not a well would be uccessful could 

not be known until the pump exhausted the water; but more than 

5,000 wells were sunk with the rude appliances in se up to 1868, 

4 McLaurin, J. J., Sketches in crude oil. 
30 WELL-DRILLING METHODS. 

before the water was shut out by inserting a larger pipe-a casingwhich was usually carried to the top of the first sand. The use of 

casing was the greatest improvement ever devised in drilling for 

oil, and holes can now be sunk safely and rapidly to a depth of 

5,000 feetv 

HYDRAULIC ROTARY METHOD. 

Although rotary methods of drilling had been used for a number 

of years previous to the opening of tl;le Spindle Top oil field in 

Texas, the remarkable success of the hydraulic rotary drill in that 

field in 1901 gave great impetus to its improvement and its more 

general use. Its work is accomplished by means of a cutting shoe 

on the bottom of the casing, the whole string of casing being rotated 

by a suitable device. As fast as the material is loosened it is carried 

to the surface by a powerful water current that is forced down the 

inside of the pipe to the cutting shoe and thence escapes upward 

between the casing and wall of the hole. In the early days of rotary 

drilling a second casing was sunk closely following the cutting shoe, 

but about 1890 it was found that thick mud used with the drill water 

puddled and plastered up the walls of the hole and was nearly as 

efficient as second casing. 

The method is adapted for use only in unconsolidated materials 

and in soft friable rocks with small crevices and pores which can be 

sufficiently plastered with mud to prevent too great a loss of drill 

water. 

CORE DRILLS. 

In drilling prospect holes for coal or for metallic or other deposits, 

or to determine the suitability of the underlying formations for 

bridge or other structural foundations, it is very desirable to obtain 

intact samples of the materials penetrated. Core drills are extensively used for this purpose, and they have been developed to a high 

degree of efficiency. As in the hydraulic rotary method, core drilling 

is accomplished by an annular shoe or bit set on the lower end of a 

string of hollow rods; but core drills are adapted to penetrating even 

the hardest rock, and instead of grinding all the material to a slush 

or mud, they remove the central part of the hole as a solid core. 

Though core drills are seldom used directly for drilling water or 

oil wells, adaptations of the core-drill principle are sometimes used 

with well-drilling outfits. (See pp. 78-88.) 

DISTRIBUTION OF DRILLED WELLS. 

_ Drilled wells are in use in most. parts of the world reached by ordinary trade routes and even in areas beyond the main lines of travel. 

In the Up.ited States they are most common in localities where flowing 
DISTRIBUTION OF DRILLED WELLS. 31 

artesian water is to be reached at considerable depths, as in North and 

South Dakota, the Atlantic coastal plain, and southern California; 

in areas where relatively deep wells are required for pure but nonflowing water, as in nearly all of the eastern States; and in localities 

where oil and gas exist, as in Pennsylvania, West Virginia, Ohio, 

Indiana, Texas, Oklahoma, Colorado, Wyoming, and California. In 

South America they are used in developing the water resources of 

desert Peru and Chile, from Callao to Valparaiso, where artesian wells 

furnish some of the municipal and agricultural water supplies. In 

Siberia portable drilling rigs have been taken to the frozen flood 

plains of the northern rivers for gold prospecting. By the enterprise 

of American supply houses and drilling firms portable outfits have 

been taken to the arid portions of Greece, Italy, and Spain, to China 

and Japan, to the oil districts of Sumatra and Rangoon, to the deserts 

of Algeria and Egypt, to Australia, and to nearly every port of cali 

in South Africa. In the couptry last named well drilling is encouraged and aided by the Cape government in utilizing underground 

water supplies for stock and for agricultural industries. The cost of 

the wells is so great that the landowner is unable to bear it alone, 

and the government therefore assists him by supplying machinery, 

material, and skilled labor, while the farmer furnishes transportation 

and Kaffir labor.a Since the value of a farm is very greatly increased 

by an ample water supply, the government of latehas required the 

:farmer to pay a much greater share of the cost of sinking a well. 

In order to show the wide distribution of deep wells and the great 

depths to which they have been sunk. the following list of 30 deep 

borings in variou~ parts of the world has been compiled. There are, 

of course, many other borings that compare favorably with these in 

depth, but those listed are illustrative. 

List of deep-well borings. 

[Data collected by B. L. Johnson.) 

Location. Depth. Diameter. Object. Remarks. 

Feet. Inches. 

East of Rybnick, Upper 6,572 3. 6 to 2. 7 Coal. ..... Cost $18,241. Completed Aug., 1893, Silesia, Germany. after 1! years' work. Deepest bore 

in the world. 

Schladeback, near Leipsic, 5, 735 11 to 1.3 Coal. ..... Cost $53,076. Completed about 1893. 

Germany. Average daily rate of drilling, 4! 

feet. 

Knurow, Upper Silesia ...... 4,173 192 to 13 ···--------- Springs, 25 miles east of 5,582 2 to li ............. Completed 1905, after 9 months' 

Johannesburg, South work. Diamond drill hole. 

Africa. 

Dornkloof, 16 miles east of 5,560 2 to ll .............. Completed December, 1904, after 14 

Randfontein, South Africa. months' actual work. Diamond 

drill hole. 

RandfonteinE South Africa ... 5,002 .................. ................... Diamond drill hole. 

Turfontein states, Johan- 4,845 --------······ ................ Do. 

nesburg, South Africa. 

a Ritso, Bernard W., The artesian wells of the Cape Colony : Rept. South African Assoc. 

Adv. Sci., vol. 1, 1893, pp. 1-21. 
32 WELL-DRILLING METHODS. 

List of deep-well bm·ings-Continued. 

Location. 

Near Boksberg on the Rand, 

South Africa. 

Clerksberg district, South 

Africa. 

In the Vlakfontein district, 

South Africa. 

In the Black Reed series, 12 

miles south of the Main 

Reef series on the Rand. 

2! miles west of West Elizabeth, Pa. 

In Aleppo Township, Greene 

County, Pa. 

Pittsburg, Pa ............... . 4 miles southeast of Wheeling, W.Va. 

In the city of Erie, Pa. _ ..... . Irwin, Westmoreland 

County, Pa. 

Buchanan well, 6t miles 

south of Burgettstown, Pa. 

Northampton, Mass .•........ New Haven Conn ........... . Renovo, Pa ................. . Bimerah Run, Queensland .. . Elderslie, No. 2, Queensland. 

Bimerah, Queensland .•...... Glenariffe, Queensland ...... . Warbreccan, Queensland .... . Winton, Queensland ........ . Darr River Downs, No. 4, 

Queensland. 

Dolgelly bore, New South 

Wales. 

One well in state of South 

Australia. 

Depth. Diameter. 

Feet. 

4,800 

4,500 

4,003 

4,500 

Inches. 

Object. Remarks. 

Diamond drill hole. 

5, 515 10 to 6i Oil........ Cost $40,000. Deepest well drilled 

with a cable; deepest well in the 

United States; third deepest well 

in the world. 

5,322 13 to 61 Gas ....... Abandoned July, 1905. 

4, 618 . . . . . . . . . . . . . . Oil or gas .. 4,500 4i ... do ...... 

1 4,460 ·······----··· •.• do •....• ' Abandoned1889. 

4, 380 ........••••••..• do •..... 

4,303 ................. do ..... . 

4,022 .............. Water .... . 4,000 8 ... do ..... . 4,000 .............. Oil. ...... . 5,045 .............. Water ..... Flow, 70,000 gallons a day. 4, 523 ................. do ...... Flow, 1,600,000 gallons a day; tem· 

4,860 

4,140 

4,125 

4,010 

4,000 

perature 202° F. 

4,086 ................. do ...... Flow, 745,200gallonsaday. 

4,420 ................. do ...... Flow, 600,000 gallons a day. 

METHODS OF WELL DRILLING. 

CLASSIFICATION. 

Modern well-drilling methods may be grouped into three general 

classes-percussion, hydraulic, and abrasion methods. 

The percussion outfits use a heavy drill bar or other tool, with 

suitable apparatus :for lifting it and allowing it to drop, to pound the 

rock into :fragments small enough to be readily removed from the 

hole. The percussion principle is utilized in the standard, portable, 

pole-tool, self-cleaning, and California methods, whose outfits are 

recognized as distinct but differ in their arrangements for handling 

the tools rather than in the operation of drilling. The California 

method belongs in this class, :for though its successful use depends 

on a plentiful supply of water, it involves drilling by percussion. 

The hydraulic outfits use water under pressure to loosen the material and bring it to the surface. The chief method in which water 

plays an active part in drilling-the hydraulic rotary method-has 

been developed mainly within the last ten years as a result of the discovery of oil in Texas in unconsolidated materials, for penetrating 

which the hydraulic rotary drill is especially adapted. In the jetting 
METHODS OF WELL DRILLING. 33 

method used for sinking water wells in unconsolidated deposits water 

under pressure plays an even more important part than it does in 

the hydraulic rotary method, for the water jet receives little aid from 

the drill in loosening the material to be removed. 

In methods involving abrasion the rock is worn and chipped off 

by rotating upon it a shoe or bit armed with some harder material. 

The abrasion principle is employed by three types of drills, which 

differ chiefly in the abrasive with which the bit is armed and are 

known as the diamond, calyx, and the chilled shot drills. 

Several methods, including boring, punching, and driving, as 

well as digging, which do not come within the above classification, 

are employed to obtain shallow water supplies. 

In many wells a single method is not employed throughout the 

entire. work, and in some wells modifications of several methods are 

successively used. Though percussion tools are usually employed in 

drilling by any of the percussion methods, the shape of the bit used 

and the means of removing the drillings may be changed at different 

stages of progress. In the hydraulic rotary outfit a percussion drill 

may be substituted for the cutting shoe in penetrating hard strata, 

and for this purpose chilled shot, or adamantine, is also occasionally 

used with a suitable revolving shoe. Combinations of the hydraulic 

rotary and the jetting methods are also employed when penetrating 

alternate beds of clay and gravel. ·In the abrasive methods it is often 

found advantageous in passing through hard or tough material to 

replace the usual bit by one operated by percussion. 

Abrasive or core drills are seldom exclusively employed for well 

sinking, their particular field of usefulness being in boring prospec.t 

holes for ore deposits or for other exploration work. 

The terminology employed by well drillers throughout the country 

is fairly uniform. This uniformity has been brought about through 

the llniformity of the terms used in catalogues of supply houses and 

through the migration of drillers from the oil fields of Pennsylvania 

and vVest Virginia to other parts of the country. One of the major 

terms that may be mentioned is the word " rig." Among standard 

drillers this is usually applied only to the derrick, wheels, and reels, 

the word "outfit" being used to include the rig, power machinery, 

tools, and accessories. Those using portable drilling machines, however, apply the term "rig" to the complete machine. 

SELECTION OF OUTFIT. 

The proper selection of a drilling outfit requires the careful consideration of many :factors, chie.f among which are the location and 

purpose of the well and the geologic structure of the rocks to be 

penetrated. In many localities, for example, small tubular wells, 

65275°-W s P257-ll--3 
34 WELL-DRILLING ME'IEODS. 

ranging in diameter from 2 to 4 inches and in depth from 50 to 200 

feet, will provide satisfactory water supplies; in other localities such 

wells are not satisfactory and wells of larger diameter are required. 

The advantage of knowing the kind of outfit to select can readily be 

understood. 

The preference of the driller must also receive consideration. An 

inexperienced man may quickly be taught to manipulate and use to 

advantage a new-style rig which a so-called experienced man, 

strongly prejudiced in favor of the rig with which he is acquainted 

can not be induced to use carefully and intelligently.. This personal 

factor the well owner or contractor can not ignore; but the man who 

condemns other well-drilling methods simply because he has found 

satisfactory in certain localities the one or two methods with which he 

is acquainted must be set down as an inexperienced or an unintelligent 

driller. 

It must be borne in mind that no one method of drilling is best 

under all conditions. No one method can even be said to be best 

under most conditions. Different methods are adapted to different 

localities; each style of outfit has advantages and disadvantages which 

must be considered before drilling is begun. The auger, elsewhere 

obsolete, is still used in many localities, as it is adapted to drilling 

shallow wells in places where a larger and more expensive rig can 

not be profitably employed. 

STANDARD METHOD. 

CHARACTER AND USES. 

The largest and deepest wells put down are those sunk to ol?tain 

oil, and the heavy standard outfit, now so extensively used, acquired 

its essential characteristics in the development of the oil industry in 

Pennsylvania. In overcoming the difficulties encountered in drilling 

deep holes the tools have been enlarged and the several parts of the 

outfit have been 'modified and improved until the size and weight 

of the tools and the ease with which they are handled surprise those 

unfamiliar with this class of machinery. · 

Standard outfits differ little in essential features, but hardly two 

can be found alike in every detail; the slight variations that exist 

are due not to some fancy or whim of the driller; but to the need for 

adapting the outfit to special conditions. 

OUTFIT. 

RIG. 

The most noticeable part of a standard outfit is the derrick, a 

pyramidal framework, .30 to 90 feet high, erected over the well. In 
U. S. GEOLOGICAL SURVEY 

A Derick foundation posts. 

A2 Mudsills. 

A3 Subsill. 

A4 Main sill. 

A5 Derrick legs. 

A6 Derrick girts. 

A7 Derrick braces. 

A8 Ladder. 

A9 Crown block. 

B Crown pulley. 

C Drilling cable. 

D1 Bull-wheel shaft. 

D2, D3 Bull wheels. 

D4 Bull-wheel posts. 

D5 Bull-wheel post brace. 

D6 Bullrope. 

D7 Bull-wheel brake band. 

E1 Calf wheel. 

E2 Calf-wheel brake lever. 

F Sampson post. 

G Walking beam. 

H Pitman. 

J Temper screw. 

K1 Band wheel. 

K2 Tug pulley. 

K3 Band-wheel crank. 

Pa 

L1 Sand-reel drum. 

L2 Sand-reel pulley. 

M1 Sand-reel lever. 

M2 Sand-reel reach. 

M3 Sand reel handle. 

N1 Sand-pump line. 

N2 Sand-pump pulley. 

0 Calf-wheel posts. 

P1 Throttle-valve wheel. 

P2 Telegraph cord and throttle valve. 

P3 Rod to reverse engine. 

Q Globe valve. 

STANDARD DRILLING OUTFIT, COUPLED FOR RAISING TOOLS. 

WATER-SUPPLY PAPER 257 PLATE I 
STANDARD METHOD. 35 

summer the derrick is usually left open except on one side, which is 

boarded in to form a shed for storing tools and workmen's clothes and 

to protect the forge-a part of the outfit that is in more or less constant use. In winter the lower part of the derrick is temporarily 

closed to protect the workmen. In a new territory drillers sometimes 

close the derrick, even in summer, to keep the results of the drilling 

secret. 

The derrick (Pl. I) consists of four legs, steadied by girts and 

braces and surmounted by a crown block. In this block is set the 

crown pulley over which the drilling cable passes. A ladder extending up one side of the derrick provides access to the orown block. 

The weight of the derrick rests on foundation posts, which are set 

deep in the ground to render the structure firm. 

At one side of the derrick are the bull wheels. This part of the rig 

consists of a reel, on which the drilling cable is wound, at each end 

of which is a wheel, usually built up of wooden arms and segments, 

fastened together with wooden pins. These parts are known to the 

trade as arms, cants, and handles. The whole is set firmly into the 

bull-wheel posts and strengthened by the bull-wheel po.st brace. The 

wheel at the farther end of the reel in the illustration (Pl. I, D3 ) is 

grooved to receive the bull rope, which acts as a belt to operate the 

reel. The brake by which the reel is controlled passes over the near 

wheel of the illustration ·and is controlled by a lever. In the early 

rigs this brake consisted of rope or a piece of old rubber belting. 

'Vhen the tools were lowered the rope would burn and smoke, and the 

rubber would emit a very disagreeable odor. In present rigs an 

iron brake band is used. 

In the California style of standard rig a second reel, known as the 

calf wheel, is placed on the side of the derrick opposite the 

bull wheels. It carries a cable that is used in lowering and in pulling 

casing. It is claimed that in deep drilling it saves much time as it 

obviates the necessity of disconnecting the tools from the drilling 

cable for these operations. 

Opposite the bull wheels is the samson post, usm11Jy about 14 feet 

long. This post is strongly braced and supports the walking beam. 

The derrick end of this beam is directly over the well and carries 

the temper screw to which the tools are fastened and by which they 

a:re fed downward. The other end of the beam carries a pitman, 

which is connected with the crank of the jack or band wheel by a 

wrist pin. This band wheel is supported on jack posts and transmits 

power to the several parts of the rig-to the walking beam by means 

of crank and pitman, and to the bull wheels through the tug wheel 

and bull rope. In the California rig. the calf wheel is also operated 

by the band wheel through a second tug wheel and rope belt. The 

operation of the calf wheel is usually controlled by a lever and clutch, 
36 WELL-DRILLING METHODS. 

and the bull wheels are usually thrown in or out of gear by putting 

on or removing the bull rope. 

The sand reel is just behind the band wheel and is operated by 

the latter through a friction pulley. This reel is mounted on a 

knuckle post and is controlled from within the derrick by means of 

the sand-line pulley, and, as its name indicates, it is used in handling 

the sand bucket or bailer. 

The part of the rig that extends beyond the derrick rests on mud 

sills, which are usually sunk in trenches and have gains cut in them 

to receive the subsills and main sill, and the whole foundation is 

carefully leveled up and firmly keyed together. 

The headache post, also called the life-preserver, is a comparatively 

recent improvement. As its name implies, its purpose is to save the 

driller from injury to the head if the wrist pin breaks or the pitman 

is thrown out of adjustment while drilling, as it prevents the derrick 

end of the walking beam from dropping and injuring anyone who 

may be beneath it. This post is usually a piece of heavy timber set 

on the main sill directly under the walking beam, so that in case of 

accident the walking beam can fall only a few inches. It is also 

useful when repairs are necessary to the pitman or the band wheel 

and crank, for a block may then be placed between the headache post 

and the walking beam, and the pitman relieved of its weight and 

slipped from the wrist pin without making it necessary to disconnect 

the tools from the temper screw. 

Variations in the size of the parts of a rig depend on the amount 

and difficulty of the work to be performed. At Bradford, Pa., where 

few of the oil wells are more than 2,000 feet deep, the derricks are 

72 feet in height; at l{ittanning, where wells between 2,000 and 3,000 

feet deep are common, the derricks are 82 feet high. An increase in 

the length and weight of the tools used is always accompanied by an 

increase in the size and strength of the derrick. The stems alone of 

the drills used at IGttanning are 39 to 42 feet long, and the sand 

buckets used with some outfits are 60 feet long. The walking beam 

used in this field is also larger than usual, being 24 feet long as compared with 16 feet at Bradford. At Kittanning the hemp drill rope 

is 2! inches in diameter; in the Bradford field it is 1! to 1 t inches. 

These figures show the structural changes that follow a change in 

the amount of work to be done. 

For a 72-foot derrick about 13,000 board feet of lumber are required for the framework and wheels, and, if the derrick is closed in, 

about 3,000 feet of siding. In places where it is difficult to get skilled 

rig builders, as in the Philippines or in newly developed oil regions, 

bolted wood derricks are very serviceable. The timbers are all framed 

and distinctly marked, so that the derrick can be easily erected. 
STANDARD METHOD. 37 

Steel derricks have not found much favor, though they ar~ easily 

taken down, transported, and set up again, and offer slight resistance 

to the wind. The driller objects to them chiefly because of the delay 

and expense entailed by the necessity of sending to the supply house 

for repairs when a part becomes broken or twisted, whereas repairs 

on wooden derricks can be made quickly by unskilled labor and 

with cheap material. The loosening of bolts-a serious defect of the 

steel derrick-has been overcome, at the expense of considerable 

additional time in erection, by using a guard nut on each bolt. 

A bolted wood or steel derrick may be set up in two or three days. 

Three or four skilled workmen can set up an ordinary nailed derrick 

in -from three to five days, the time depending on the size of the rig 

and the quality and accessibility of the lumber; but after a nailed 

derrick has been used for two or three jobs it becomes too badly worn 

and racked to be set up again. 

vVhere oil wells are drilled close together, or where, on account of 

trees or buildings, there is limited space for operation, a rig with a 

short walking beam is sometimes used. This rig occupies a plot about 

20 by 50 feet in size, and is very compact and serviceable. 

ENGINE AND BOILER. 

Beyond the derrick and other parts of the rig is the engine, which 

furnishes power to the band wheel by a belt. Steam power is almost 

universally used and is supplied by a boiler placed a short distance 

from the engine. The throttle of the engine is controlled from the 

derrick by a double line of telegraph wire passing over small pulley 

wheels, and the reverse lever is operated by a rod that extends from 

the engine in to the derrick. 

A good engine and boiler are just as essential as a good drilling 

machine, and these parts of the outfit should be selected very carefully. The boiler used in connection with the standard rig ranges 

from 15 to 40 horsepower and the engi~e from 12 to 30 horsepower. 

Boilers are of two general types-horizontal and upright. The horizontal-called the oil-country boiler· (see Pl. I, Q)-is in most general 

use. The upright boiler differs from the horizontal mainly in shape, 

but is smaller than the oil-country boiler, and is more easily moved 

and set up. It is used in some parts of the California fields, where 

it is closed in with natural adobe instead of brick. In many oil and 

gas fields either oil or gas may be obtained from other wells for 

fuel under the boiler. 

Engines of various styles are used even in the same locality, but 

all are usually so fitted that they can be controlled from the derrick 

and are otherwise adapted to the particular needs of the work. 

Water for the boiler and for use around the well may be obtained 

from a near-by water well or from a neighboring stream. If the 
38 WELL-DRILLING METHODS. 

source of supply is not too distant, a hose or pipe is led to the outfit 

and water is drawn by a steam pump, but if the distance is considerable the steam pump is put near the well or stream and water is 

:forced up to a storage tank at the place where drilling is to be done. 

Steam may be supplied to the pump through insulated pipe led from 

the boiler, or a gasoline engine may be set up near the pump. Gasoline engines are used with many outfits in Indiana and Pennsylvania 

and are said to be more economical and to require less care than steam. 

Where there is no near-by well or stream from which a water supply 

can be obtained, a water well is sunk by means of the outfit before 

work on the oil well can be begun. The water well is usually put 

down immediately beneath the walking beam, about 3 feet back from 

the point where the deep hole will be drilled, in order to lessen the 

labor of drilling it and of pumping the required water. Water for 

drilling this well and for the boiler is hauled from the nearest available source. After a water supply has been obtained, a pump is so 

installed that it can be connected with the walking beam, by which it 

is operated when water is needed. 

In the vicinity of Bradford, Pa., water is obtained from wells 

about 60 feet deep in the valleys and 200 to 300 feet deep in the hills. 

The cost of sinking water wells adds considerably to the expense of 

putting down oil wells. 

TOOLS. 

The string of tools used in deep drilling consists of several parts, 

all of which have certain definite functions and are the outgrowth of 

years of experience. A full string (fig. 5, A) comprises rope socket, 

sinker bar, jars, auger stem, and bit. Whether or not the complete 

string is used depends on the conditions under which drilling is 

done. 

The socket may be fastened to the drilling rope ·in several ways. 

It may have a tapered hole in which the rope is secured by knotting; 

the rope and socket may be riveted together, or the rope may be 

threaded back and forth through several holes in the socket and secured by wedging. 

The sinker bar is a long, heavy bar, which is used to add weight 

and length and thus aids in keeping the hole straight. It was for-

, merly thought to be an essential part of the string, but it is now 

seldom used unless a wet hole (one partly filled with water) is being 

drilled. It then assists in sinking tlie cable rapidly. If it is placed 

between the jars and the bit, it adds force to the blows of the latter. 

The jars, as previously stated, consist of a pair of linked steel bars. 

"'Vhen drilling in rocks in which the bit is apt to stick they are necessary to "jar" the drill loose. The drill responds to the powerful 

upward blow of the jars as they are jerked violently together by the 
STANDARD METHOD. 39 

stroke o£ the walking beam 

when it will not yield to the 

slow and relatively steady pull 

of the rope. In ordinary brittle 

rock the jars are now almost 

univ~rsally discarded, but they 

have a very important use in 

" fishing " :for lost tools ; those 

intended :for this purpose are 

made longer than jars used in 

ordinary drilling. 

The jars in no sense act as a 

maul to drive the drill into the 

rock, as many people suppose. 

In :fact, a good driller so adjusts 

the cable that it is impossible 

:for the upper jar to strike the 

lower one except when the cable 

is raised. The only weight 

which adds effectiveness to the 

blow o:f the drill is the weight 

o:f the lower jar, the auger stem, 

and the drill. The weight o:f 

these three parts, or o:f the two 

last-named parts, makes up 

three-fourths to seven-eighths 

o:f the total weight o:f the string 

o:f tools. This weight, :falling 

through a distance o:f several 

:feet, is all that the drill can 

bear. Some inexperienced drill 

men give the drill too much 

rope, so that the bottom o:f the 

upper jar strikes into the bottom o:f the slot o:f the lower jar 

at each downward stroke, and 

in a short time the links are 

seriously damaged. The stroke 

must be carefully adjusted to 

the play o:f the jars, taking into 

account the stretching o£ the 

rope. 

The auger stem gives additional weight to the blows that 

are struck, and also, by increas-

.-I 

I 

I .,, 

ol 

31 

o, 

~I 

UQI 

I 

I 

I 

_±_ 

FIGURE 5.-A., String of tools used 

with standard drilling outfit; 

.4 B, temper screw. 
40 WELL-DRILLING METHODS. 

5 

4 

3 

2 

ia 6b 8 9 10 

FIGURE .6.-Drilllng tools used with standard drilling outfit. 1-5, Bits ; 6•, 6b, reamers ; 

7, rope clamp ; 8, 9, sand bailers; 10, sand pump. 
STANDARD METHOD. 41 

ing the length of the drill, helps to maintain a straight hole. It is 

of the same shape as the sinker bar, but is considerably shorter. 

Various patterns of drilling bit are used, according to the character 

of the rock that is being penetrated. The shape illustrated at the 

bottom of the string of tools in figure 5, A, is used in moderately 

hard rock; the " Mother Hubbard " pattern (fig. 61 ) is a similar, 

but thicker, drill that is us_ed in hard, fissured rock; the California 

pattern (fig. 62 ), which is concave on the bottom, is much ursed 

in the shales of the oil districts in that State. A shorter, lighter bit 

(fig. 63 ) is used in "spudding" at. the beginning of drilling. Star 

bits (fig. 64 ) are sometimes used in creviced rock that dips st~ply, 

and more complex. shapes are used in reaming and in other special 

operations. 

All joints of the -string of tools have taper screws, so that only· a few 

turns are required to fasten them together. They are screwed up 

tightly by heavy wrenches on which great leverage is exerted by means 

of a ratchet floor circle and jack (fig. 7, .A.), or by a simpler arrangement (fig. 7, B) in which the floor circle is an arc of band iron with 

holes punched in it every 2 or 3 inches. These holes give footing to a 

bar by which the upper wrench is forced around. The great stress 

that is thus brought on the screw joints binds the string of tools 

together. When first assembled and screwed together tightly each 

joint of the string may be marked by a cold chisel cut that extends 

across it, and each time a joint is put together care is taken to see that 

it is screwed up as far as or a little farther than it was before. If the 

two halves of the chisel mark fall short of coinciding, sand or mud in 

the threads may be the cause, and if this material is not removed and 

the joint screwed together tightly, the sand may work out, leave the 

joint loose, and cause loss of all tools below the joint. 

TEMPER SCREW. 

The cable supporting the string of tools is connected to the walking 

beam by a temper screw (fig. 5, B), which allows the drill to be fed 

downward as the drill hole is deepened. The temper screw consists 

of a frame or reins, at whose lower end is a split nut held together by a 

yoke clamp. . Through this nut the main screw passes, and to its lower 

end is fastened a handle, by which it is turned. Below the handle is 

attached a ball-bearing swivel, from which depend the clamp links and 

rope clamps. The cable is gripped tightly between the rope clamps 

by a C clamp and is prevented from slipping by means of a "cat," 

made of strands of raveled rope or strips of coarse cloth, loosely 

plaited or twisted so as to form a cord about as thick as a man's fi~ger 

in the middle, and tapering toward each end. The "cat" is wound 

about the cable at the point where the clamps are attached, and the set 

screw is then turned so as to bring the rope clamps firmly against it. 
42 WELL-DRILLING METHODS. 

Slightly different forms of clamp (fig. 67 ). are sometimes used 

with wire rope. . 

When the screw has been run out its full length, and it is desired 

to bring it up again, the slack of the drilling rope is taken up on 

the bull-wheel shaft, the pitman of the walking beam is disconnected, 

..and the C clamp is loosened. The yoke clamp is then loosened, the 

main screw is drawn up through the split nut, the yoke clamp is. 

again tightened, and the temper screw clamped to the cable. Small 

A 

B· 

FIGURE 7.-Floor circles: A, Rachet and jack; B, bar and perforated arc. 

ropes are fastened to the short crossbar, or elevator, at the upper 

end of the main screw, and by pulleys on the under side of the walking beam a counterweight is hung beside the samson post. This 

weight balances the temper screw and renders its raising easy. 

A device employing hydraulic feed and intended to replace the 

temper screw has been patented within the last few years. It is attached to the walking beam in the same position as the temper screw. 
STANDARD METHOD. 43 

It is simple in construction and operation, as it consists essentially 

of a cylinder containing a piston to which the cable is attached. 

Water may be admitted either above or below the piston, and by regulating its flow from the lower to the upper part of the cylinder the 

piston and tools are allowed to descend slowly as the hole is deepened. 

When the piston reaches the bottom of the cylinder. the tools and 

piston rod are again elevated to the top, a process similar to that of 

raising the temper screw in that it involves a cessation of drilling. 

With both devices, however, the adjustment is usually made only 

when the tools are withdrawn· for sand bucketing the well. 

The device has been patented too recently and used too little to 

enable one to judge of its merits. As it has a larger number of small 

and special parts than the temper screw, its use will not be approved 

by many drillers, for it may cause expensive delays when parts are 

broken. Accidents to the temper screw may usually be remedied by 

a local blacksmith. The new device is more easily manipulated than 

the temper screw, however, and this advantage may lead to its 

adoption. 

CABLE. 

Both hemp and steel-wire ropes are now used for drilling cables, 

the steel wire having come into more general use during the last ten 

or fifteen years. 

The best quality of hemp rope is that made of manila hemp (not 

common hemp nor sisal) and is hawser laid, that is, it consists of 

th,ree ropes of three strands each, twisted together into a single rope. 

In its manufacture a "nap" is formed, of the ends of hemp fibers, 

nearly all of which point toward one end of the rope. The rope socket 

should be fastened to the end toward which the fibers point, for 

although when the tools are attached to this end the fibers spread 

out and retard the downward stroke in a hole that is partly filled with 

water, they protect the rope better from being frayed by rubbing 

against the casing on the upstroke. 

Steel-wire drilling cable is composed of several strands wound 

about a hemp center, each strand being formed of several wires. 

Rope consisting of six strands of seven wires each is a style commonly 

used. 

The advisability of substituting steel-wire cable for hemp cable 

in drilling deep wells has been much discussed, some maintaining that 

hemp can never be replaced by steel, and others that steel will shortly 

be used altogether. The importance of the substitution of steel for 

hemp is better appreciated when it is known that a hemp cable ordinarily can not be used to drill more than one or two wells, but the 

hemp cable possesses certain important qualities which are not found 

in the steel cables and which must be considered in dealing with the 
44 WELL-DRILLING METHODS. 

problem. The careful driller never allows his tools to fall as a dead 

weight on the rock which he is drilling, but so adjusts the rope that 

the tools will stretch it in reaching the bottom of the hole. The 

nature of this action may be illustrated by suspending a weight by 

a piece of rubber elastic a little above a table or other surface. It 

will be found that by giving a slight reciprocal motion to thee rubber 

the weight may be made to strike the surface with considerable force. 

Manifestly, the force of the blow is diminished by this arrangement, 

but in drilling this loss of force is more than compensated by the 

springing blow that is struck; and if the rock is easily cut by the 

drill this rebound is essential, as otherwise the drill will be imbedded 

so firmly as to make it difficult to remove except by jarring. 

In drilling a deep well the stretch of the rope is often underestimated, and it may happen that the tools are falling when the walking 

beam is rising, thus bringing a great strain on the cable and making 

the blows of the drill very ineffective. The operation. of the tools 

is rendered still more difficult when the hole contains several hundred 

feet of water, which interferes with the free upward and downward 

motion of the cable. 

Steel cable, with its smaller diameter and greater weight, has the 

advantage of passing comparatively freely through water which may 

stand in the drill hole, the water friction being much less than on a 

hemp cable, and the water also reduces the shock of the steel cable 

by acting as a deterrent to the rapid drop of the tools. On the other 

hand, steel cable has very little elasticity, and drilling by the stretch 

of the rope is hardly possible. Every blow that is struck by the drill 

is a dead blow, as there is no compensating rebound and the upward 

stroke causes severe strain, both on the derrick and on the cable 

itself where it is attached to the tools at its lower end and to the 

temper screw at its upper end. The difference in stretch of the two 

kinds of cable is shown by the fact that with a 5-foot temper screw 

7 or 8 feet may be drilled with hemp cable, while at best a distance of 

only 5f feet is possible with steel cable. Some drillers use 150 or 

200 feet of hemp rope between the tools and the steel rope, and this 

gives some elasticity to the cable and rebound to the tools. 

The use of the steel cable was considerably increased during the 

Spanish-American war by the fact that the price of hemp cable became so high that its use seriously increased the cost of a well. 

In the last few years at least half of the oil wells put down in the 

California fields, where the wells are usually drilled" wet," have been 

drilled with steel cables. In other oil fields a very small proportion 

of the ddlling is done with steel cables. For cleaning wells, however, it has largely supplanted hemp cable throughout the East, as 

in this work it is not necessary to use such a rapid stroke, and hence 

steel cable may be advantageously employed. 
STANDARD METHOD. 45 

Experiments have been made by several supply companies looking 

toward the construction of some device that will give elasticity to a 

~teel cable, but the thousands of dollars thus spent have had little 

practical result. Several experimenters, however, are continuing 

this investigation, working along the.line of a spring fastened to the 

walking beam, the whole being adjusted in such a way that the spring, 

when given the proper tension, will take up the slack of the cable on 

the upward stroke and give it out again under the weight of the 

tools on the downward stroke. Experiments are also being made 

with a cushioned walking beam, looking toward the same result; and 

it is possible that a sufficient degree of efficiency may be reached in 

the construction of this device to permit the wider substitution of 

steel for hemp in future drilling operations. 

The standard well-drilling outfit with steel-wire drilling cable has 

been used to some extent in the Baku oil region of Russia, where it 

was found that· only a very limited amount of rotation could be 

imparted to a wire rope without damaging it, because of the untwisting and kinking of the strands. To overcome this disadvantage a 

special kind of wire rope was employed, consisting of left-hand and 

right-hand strands plaited together:. It is said that this rope worked 

t<atisfactorily in the hands of a skillful attendant, but it had to be 

disconnected from the main drum at each change of operations. 

DRILLING OPERATIONS. 

SPUDDING. 

The term " spudding " is often misunderstood. By some people it 

has been thought to mean the preliminary part of drilling, without 

reference to the way in which the drilling is conducted; by others it 

has been interpreted to mean drilling in rock of unusual hardness. 

Properly, however, the term is applied to drilling without the aid of 

the walking beam-the method nearly always used in sinking the first 

75 or 100 feet of a well, as the string of tools is too long to be operated 

from the walking beam in beginning work. It is possible to attach 

the tools to the drilling cable before the hole has been drilled to this 

depth, but owing to the short length of cable between the tools and 

the walking beam there is very little "spring" in the rope, and the 

hole must be spudded to a sufficient depth to allow a considerable 

length of cable to come between; otherwise the blow of the drill will 

be "dead" and the rope will Be likely to break. 

For spudding a short cable is run through the crown pulley at the 

top of the derrick, one end being attached to the bull-wheel shaft and 

the other to the rope socket, to which are usually screwed only the 

auger stem and spudding drill. The drill may be given an up-anddown motion in two ways: In the first method the rope is carried 
46 WELL-DRILLING METHODS. 

around the bull-wheel shaft in two or three turns, its end being left 

free. A man standing in front of the bull wheels grasps this free 

end of the rope and gives a slight pull, causing the coils to tighten 

and grip the revolving shaft, and by this means raising the tools; 

when the rope is slackened the tools fall. By alternately tightening 

and slacking the rope the operator may raise and drop the drill. 

The second method has come into use comparatively recently and is 

much more effective than the other. In this method, which is selfadjusting, the drill rope is wound firmly about the bull-wheel shaft 

·and passed through the crown pulley, and from its end the tools are 

suspended in the drill hole. A rope called the jerk line is attached to 

the wrist pin of the band-wheel crank, brought inside the derrick, 

FIGURE. 8.-Standard rig arranged for spudding. 

and attached to the part of the drilling cable which extends from the 

crown pulley to the bull-wheel shaft by a curved metal slide called 

a spudding shoe. (See fig. 8.) By carefully adjusting the length 

of this rope each revolution of the band wheel results in a pull on the 

line and its subsequent release, and a corresponding rise and fall of 

the tools. As the hole is deepened the cable is let out by giving the 

bull-wheel shaft a partial revolution, and the spudding shoe is 

slipped farther and farther down, for this downward sliding of the 

spudding shoe increases the length of the pull on the drilling cable 

and hence the distance through which the drill drops. The sliding 

motion is imparted by the driller's assistant, between the jerks of tl1e 

line, by means of a crooked stick long enough to reach the spudding 

shoe from the floor of the derrick. 
STANDARD METHOD. 47 

Spudding is much harder on the derrick than is ordinary drilling, 

as the strain is brought on the top of the derrick where there is the 

greatest leverage. In drilling with the walking beam the weight 

comes on the samson post, which is not directly connected with the 

derrick, and the strain comes on the derrick only when raising or 

lowering tools or casing and when using the sand bucket or the bailer. 

DRILLING WITH THE W ALXING BEAM. 

After the hole has been sunk to the depth required for the string 

of tools a heavier drilling bit is attached, the drill rope is suspended 

from the walking beam by the temper screw, and regular drilling by 

means of the walking beam is begun. To allow freedom of motion 

to the walking beam, 20 or 30 feet of the drill rope are unwound from 

the bull-wheel shaft and loosely coiled on the floor. The pitman of 

the walking beam is then fastened to the wrist of the band-wheel 

crank. The crank is provided with a number of holes, so that the 

length of stroke can be adjusted to the depth of the well, a short 

stroke being used near the surface, as the strain would otherwise be 

too great for the rope to bear. The engine ·is then started and the 

walking beam begins rocking up and down, raising and dropping the 

tools at the rate of about 25 strokes a minute. 

Until within the last few years it was the custom to revolve the 

drill by inserting a stick in the rings below the temper screw and 

slowly turning the rope first in one direction and then in the other. 

This was thought to insure a round hole by causing the drill to 

strike each time in a different place. One day a tired workman, who 

wondered if this operation was necessary, neglected this precaution 

and found that the drill still made a round hole, a fact that had often 

been inferred by drillers who had seen the tools revolve and bring the 

drill in a new position for each stroke. The drill is jerked free from 

the rock unevenly, and the torsion of the drilling cable under the 

lifting strain has the effect of rotating the tools in one direction on 

the upstroke and in the other on the downstroke. This action, however, 

takes place to a notable degree only when there is a sufficient length 

of rope between the tools and the walking beam; until a considerable 

depth is reached it is often necessary to turn the cable by hand, otherwise the drill may strike successive blows in the same place, but it is 

now rightly considered that after the hole is 200 or 300 feet deep it is 

needless to turn the rope while drilling. 

The skilled workman takes hold of the rope or swivel often, for 

by the feel of the rope he ascertains whether the string of tools is 

intact and the drill is cutting the rock. When the drilling bit strikes 

the bottom of the well, the cable is drawn taut and conveys the 

vibration to the driller's hand; by this means he soon learns when to 
48 WELL-DRILLING METHODS. 

adjust the temper screw. In the same way the operator learns 

whether or not the jars open and shut at each blow of the drill. 

The proper tension of the cable can be determined only by practice. 

An old cable has more spring to it than a new one; and the weight 

of the drilling tools, the depth of the hole, and the speed at which 

the machine is running must also be taken into consideration. Ordinarily the engine should be speeded up until the c.able tightens 

slightly in advance of the stroke of the drill, not so as to retard its 

fall, but so that when the drill touches bottom it will be instantly 

lifted, with no time either to settle or stick. This careful adjustment 

of the stroke is absolutely necessary for rapid and skillful work. 

I£ the drill touches bottom when at rest, there is too much rope out 

and it should be taken up with the temper screw, for the downward 

stroke of the drill will stretch the rope sufficiently to let the bit 

strike the bottom of the hole. 

The motion of the drill will be greater than that described by the 

walking beam, unless too much cable is let out, in which event the 

stroke of the drill will be less than the stroke of the walking beam, 

the strain. on the cable will be greatly increased, and little or no 

progress can be made. One of the hardest things for a beginner to 

learn is that he can not make the drill GUt faster by letting out more 

cable. With a hemp cable, at a depth of about 50 feet, when the drilling tools are at the lowest point in the stroke, the point of the bit 

should hang 2 or 3 inches above the bottom of the hole. At 100 feet 

it should be ~! or 5 inches; at 200 feet it should be 6 to 12 inches; and 

at greater distances with greater depths. An unskilled driller will 

sometimes allow the full weight of the tools to fall on the drill rope, 

the drill actually being stopped in its descent a short distance above 

the rock in which it is supposed to be cutting. The likelihood of such 

an occurrence increases with the depth of the hole, for the increasing 

weight of the drill rope added to the weight of tools, often several 

tons in all, makes it difficult to detect by the " feel of the rope " 

whether or not the total weight is decreased at the end of the stroke 

by the weight of the tools below the jars. 

As the drill cuts deeper it is necessary to let out the drill rope gradually, so that the drill will strike bottom at each stroke. This is done 

by loosening the yoke clamp a little, and running out the temper 

screw a turn or two. At the end of from half an hour to several 

hours the temper screw has been run out its length of several feet and 

the drill has advanced an equal or greater distance. The tools are 

then withdrawn, the waste that has accumulated since th~ last bailing 

is removed with the sand bucket, and if necessary a sharpened bit is 

substituted. 

The withdrawal of the tools is accomplished by first taking up the 

slack cable on the bull-wheel shaft, thus transferring the weight of 
STANDARD METHOD. 49 

the tools to it through the crown pulley. The rope clamp is then 

loosened, the temper screw is disconnected, and the pitman ~s thrown 

off from the band-wheel crank pin, as in figure 8. By rotating the 

bull-wheel shaft with the engine connection, the tools may then be 

raised or lowered at will. This part of the work demands skill, for 

if the bull-wheel brake should not be applied as the tools reach the 

surface, the crown block and pulley would be torn loose and the tools 

would fall on the workmen beneath. After the tools are clear of the 

hole, they are swung to one side and caught in the loop of a quarterinch rope fastened to a leg of the derrick. 

The operator is now .ready to bucket the drillings from the well. 

The sand bucket, or bailer, consists of a section of tubing 15 to 60 

feet long and somewhat smaller than the well. It has an iron valve 

at the bottom, either of the flat pattern, or the ball and tongue 

pattern. (See fig. 6 s-9 .) In some materials in which the drillings 

are thick and heavy and do not readily enter the bailer, a sand pump 

(fig. 610 ) is used. In addition to the bottom valve this has a 

plunger which is worked like that of a water pump, and thus sucks 

the drillings into the tubing. The bucket or pump is suspended from 

a wire cable that is wou~d on the sand-line reel and carried through 

the sand-line pulley. The reel is operated from the derrick by a 

lever, which brings its friction pulley into contact with the band 

wheel. The sand-bucket line is thus wound up and the sand bucket 

is swung over the hole. The friction bearing on the band wheel is 

then released and the bucket is lowered into the well at any desired 

speed. As the drillings form a thin mud, owing to the addition of 

water from time to time by the driller, they rise into the sand bucket, 

are retained by the valve in its bottom, and are then removed. The 

bucket is emptied by lowering it upon an upright stake or pin beside 

the well, thus opening the valve. 

The liquid condition of the drillings often makes it possible to 

drill 5 or 6 feet without bucketing; otherwise the drill would become 

ineffective at the end of a very short time, by striking into its own 

cuttings, and the necessity for frequent bailings would greatly increase the work and cost of drilling. Water is usually added to the 

drillings by the bucketful at the well head. Sometimes it comes into 

the well from water-bearing strata that have been penetrated by the 

drill in a quantity sufficient to soften up the drillings, and yet not 

great enough to interfere with .the work. It is then unnecessary 

to pour in water from the surface. 

In many localities water is added to the drillings by means of a 

barrel set at one side of the derrick, from the lower end of which 

a pipe extends within 2 or 3 feet of the drill hole; to this pipe is 

fastened, by a loose joint, anotber piece of pipe as long, at least, as 

the height of the barrel and long enough also to reach from the end 

65275°-W s P 257-11---4 
50 WELL-DRILLING METHODS. 

of the horizontal pipe to the mouth of the drill hole. When the 

short length is dropped to a horizontal position water flows from 

the barrel down into the hole; by raising the short pipe to a vertical 

position the flow is shut off. 

DRESSING THE BIT. 

As the bit gradually becomes worn on the edges, its diameter is 

constantly reduced-that is, it loses its gauge. When the tools are 

withdrawn, if the bit has become noticeably worn, the screw joint 

connecting the bit and auger stem is " broken " by means of the 

wrenches and floor circle, the bit is unscrewed and removed by 

hand, and a freshly dressed bit is then substituted. During the 

first part of this operation the tools are steadied by keeping them 

partly in the drill hole. At this time the whole string of tools is 

usually examined, and each joint is "set up" in turn, as the constant and tremendous jarring to which the tools are subjected tends 

to loosen the different parts. Before drilling is resumed the temper 

screw is also screwed up or " elevated " so that it can be fed down as 

the drill hole deepens. The tools are then let down again and 

. drilling is resumed. 

The worn bit is heated in the forge, the circular tool gauge is 

slipped over while it is hot, and the edges of the drill are hammered 

out to fit the gauge, which has a diameter one-eighth inch greater 

than the required diameter of the bit to allow for contraction due to 

cooling. In heating the bit it should be turned occasionally to get an 

even heat, and brought to a cherry red for a distance 3 or 4 inches 

back from the end, so that in hammering it the outer part will not 

tend to spall off. It is usually spread with a sledge, working from 

the center to the edges, to a diameter a little larger than the gauge, 

and then hammered down to proper size. The edge should not be 

made very sharp or it will tend to drill a three-cornered hole. In 

tempering the end is heated until it shows bright cherry red in the 

shade, then placed upright in li or 2 inches of water so as to cool only 

the part to be tempered. After a minute or two, when the edge is 

cool, the bit is removed until the heat flows back into the end and 

causes it to pass through straw, orange, and purple to a blue color. 

It is then re-immersed and allowed to cool. The treatment gives the 

proper temper for drilling moderately hard rock. If the bit is cooled 

at one of the· colors that appear earlier, it will be too hard and brittle 

to work well, and if allowed to wait longer before tempering it 

will be too soft. The upper (threaded) end of the drill should be 

thoroughly cooled before it is screwed to the stem, otherwise subsequent shrinkage may cause the joint to loosen. 

As the bit becomes worn by continued drilling, the size o£ the hole 

is correspondingly decreased. In hard sandstone one-quarter to three~ 
STANDARD. METHOD. 51 

eighths of an inch may be worn from the width of the bit in drilling 

3 or 4 feet, so that when a newly dressed bit is introduced it may 

find the last few feet too small, and may work hard or even stick for 

the first few strokes. A well-worn bit will cut a hole no larger than. 

its shank, but a newly dressed bit provides clearance, like the teeth 

of a newly set saw. To prevent sticking the bit is run up and down 

a few times and turned constantly. It is thus prevented from forming a groove which it would tend to follow so as to direct the repeated strokes of the drill in the same place. When the rock is very 

hard and the bit is more rapidly worn jars are necessary to prevent 

accident to the drill rope by the sticking of the drill. 

WET AND DRY DRILLING. 

A " wet " hole is one in which \Yater in excess of that required for 

the operations is present while drilling; a" dry" hole is one in which 

excess water is cased off during the sinking of the well. In oil fields 

these terms are applied in a different sense, a wet hole being a well 

which yields oil and a dry hole one which does not. 

In a dry hole the drilling can be done faster, as 1the tools are not 

buoyed up by water; the rope lasts longer because it is not always 

saturated; small showings of gas and oil are more readily detected and 

their depths are more accurately determined; and if the tools are lost 

in the hole, they can be more easily recovered, as fishing tools are used 

to better advantage in a dry than in a wet hole. At Bartlesville, 

Okla., three water-bearing sands are encountered in drilling for 

oil. Dry drilling in that field is regarded as so much more satisfactory than wet drilling that three strings of casing are inserted to keep 

the water out. Two of these are withdrawn when the well is completed, the last one that is inserted being kept in service to retain the 

oil and prevent the well from caving. 

Wet drilling is usually cheaper (there being no outlay for additional casing), no time is lost in putting in casing and replacing the 

tools by a smaller set; and when the well is down, the charge of 

nitroglycerine used in shooting the well has much greater effect, as it 

is tamped by the heavy column of water. The greatest disadvantage 

of wet drilling is that the sides of the hole are kept so wet that some 

of the shales are reduced to a semifluid mud, which frequently caves. 

Another disadvantage is that when tools are lost there is danger of 

sand and mud settling around them, even if the sides of the well do 

not caYe. 

CASING THE WELL. 

CONDUCTOR BOX. 

In many places the surface material consists of loose sandy clay, 

sand, and gravel, varying in thickness (in the Penm~ylvania oil 

regions) from a few feet on the hills to several hundred feet in the 
52 WELL-DRILLIN"G METHODS. 

valleys. To restrain this material, which would otherwise impede 

the work of drilling, a conductor box, made of plank, circular, square, 

or octagonal in shape, and 8 inches to 20 inches across, is sunk to the 

bed rock. If the rock lies only a few feet below the surface the 

necessary excavating is done by hand; if the soil is deep, a large 

drilling bit is used to spud down a hole, into which the conductor 

box or a section of large iron pipe may be sunk as fast as drilling 

proceeds. 

CASING AND DRIVE PIPE. 

After passing through the surface mater-ial the drill enters the 

"live" rock. As a rule this rock is made up of alternating layers of 

hard and soft,· of very porous and slightly porous, of water-bearing 

and nonwater-bearing rock. Unless .the water in the rock is under 

notable head and is considerable in amount, it is welcomed by the 

driller, as it saves the trouble and expense of pouring into the hole 

sufficient water to keep the drillings liquid. If, however, the water 

coming into the hole is too great for rapid drilling, it is necessary . 

for the driller to insert a string of casing extending from the surface 

into the first hard, nonwater-bearing rock that is encountered after 

passing through the water-bearing layer. This casing js set very 

firmly into the hard layer and shuts out the water. In order to continue drilling, it is necessary to use a smaller bit which will pass, 

with clearance, inside the casing. If other heavy flows of water are 

encountered at 'greater depths, each flow must be cased off by a string 

of casing extending from the surface to the bottom of the waterbearing layer. As each string must slip inside the preceding one, a 

smaller drill must consequently be used after each casing operation. 

The first well lining used in this country was in the celebrated well 

drilled by Colonel Drake on Oil Creek, Pennsylvania. Some of the 

early drilled wells of small diameter were lined with pipe made of 

riveted or soldered sheets of copper. · Before long this was superseded 

by drive pipe with soldered brass screw joints, such as is still used in 

the salt wells of Tarentum, Pa. 

Several varieties of casing are now used. Sheet-iron riveted pipe 

is extensively employed in the Russian oil fields, but it is little used 

in oil wells in the United States. It is rather short lived, and the 

corners of the bit are apt to catch on it in drilling and cause breaks. 

Another kind of pipe used, known as oil-well casing, ranges in usual 

sizes from 4 to 12 inches, inside diameter, and is made in several 

weights. A third kind, called steam pipe, is also made in sizes up to 

12 inches and in three grades-standard, extra strong, and double 

extra strong. Still another kind of lining is the regular drive pipe, 

which is made very heavy in order that it may be driven to great 

depths. The ends of the pipe are cut off smoothly and meet squarely 

in the middle of the sleeve coupling (fig. 9 1 ). In this way the 
STANDARD METHOD. 53 

2 n 

3 

DO 

7 8 

4 

5 

c 

9 

11 10 13 

· FIGURE 9.-Couplings and casing attachments. 1, Sleeve coupling; 2, tapered sleeve 

coupling; 3, 4, sleeve and inserted joint couplings; 5, shoe; 6, 7, 8, drive heads; 9, 

drive clamps; 10, pipe ring; 11, hydraulic jack; 12, elevator; 13, gas packer. 
54 WELL-DRILLING METHODS. 

whole strain in driving comes not on the threads, but on the pipe; 

otherwise the joints would be disabled before reaching any considerable depth. 

If a cheap well is desired, heavy wrought-iron pipe is driven to 

rock, and the well is finished by drilling to the required depth. A 

casing made of sheet iron, one-sixteenth inch thick and one-half inch 

smaller than the drilled hole, is then used. If it is necessary to shut 

off sand the bottom of this pipe may be flanged outward a little. 

After the sheet-iron pipe has been placed in the well the heavy pipe 

may be pulled out and used again. If the depth to rock is not more 

than 50 or 75 feet and the material is all clay or earth which will not 

cave, the heavy pipe may not be used at all, the sheet-iron pipe serving 

in its stead, though its use in this way is attended by considerable 

risk. 

Casing is usually a lighter and cheaper pipe than drive pipe, as it 

has little outside pressure to withstand. A tapered sleeve coupling 

(fig. 9 2 ) is often used with it. In this form of coupling the last 

thread in the tube is the weakest and most likely to break in case o:f 

accident, and the pipe is easier removed than if the whole thread remained in the tube. Flush joint and inserted joint couplings (fig. 

9 3

- 4 ) are also used with casing that requires little driving. After a 

few wells have been sunk in a district the approximate amount of 

casing that will be required for~· well can usually be estimated, since 

the depth to troublesome water-bearing formations is then roughly 

known. 

In gas wells, where dryness i~ essential, all the strings of casing are 

usually left in the well to prevent water near the surface :from sinking to the lower end of the last casing, where it would be under 

great head and might force its way through a weak spot at the point 

of juncture of the casing with the rock. As a cubic foot of water 

"\Veighs about 62t pounds, the pressure, in pounds per square in.ch, of 

the column of water in the drill hole is equal to the height of the 

column in feet, multiplied by 0.434. Therefore at the bottom o:f a 

well 1,500 feet deep water that enters and fills it up to the 500-foot 

level exerts a pressure of 434 pounds per square inch. This is the 

crushing stress on the pipe provided there is no internal column of 

liquid to counterbalance the external column, as, of course, there is 

not in a producing gas well. 

In deep drilling, where caving material may be encountered, it is 

customary to sink casing, or drive pipe, as fast as drilling proceeds. 

For this purpose pipe heavier than the usual casing is employed, and 

stronger joints are made generally by heavy sleeve couplings (fig. 9 1 ). 

On the bottom of the lower joint there is screwed or shrunk a 

shoe of tempered steel (fig. 9 5 ), which will stand heavy driving 

without injury, and which gives clearance for the pipe and couplings. 
STANDARD METHOD. 55 

The ordinary pipe would be greatly damaged in driving long distances if it were not protected by this shoe. To prevent the top of 

the pipe frmn being battered, a drive head (fig. 9 6-') is screwed 

or placed on it. In some places the material is so loose that the tub--

ing will follow the drill for some distance without requiring to be 

driven; but when driving becomes necessary drive clamps (fig. 9 9 ) 

are bolted to the pin square of the upper end of the auger stem. 

The machinery is then coupled as for spudding, and 50 or 60 blows 

a minute are delivered by this driving clamp to the drive cap on the 

top of the pipe. The pipe may also be driven by a heavy wooden 

maul attached to the drill rope. In this case a solid drive head 

(fig. 9 8 ) is used, and proper direction and effectiveness are insured 

to the blows by means of temporary guides set within the derrick. 

Sometimes in drilling through a compact formation, such as clay, 

the pipe becomes lodged, owing to the projection of the couplings. 

'Vhen this happens a cap is screwed to the drive pipe, and water is 

forced down it so as to come up outside of the pipe and loosen the 

material about the coupling. 

vVhen the pipe has been driven as far as practicable drilling is 

resumed. The driller endeavors to keep the hole sunk a few feet 

ahead of the casing, for in this way the casing is let down straight, 

whereas if the pipe is driven ahead of the drill, it may be deflected 

from its course by changes in the hardness of the material or by 

encountering a bowlder or a layer of coars~ gravel. 

This method, however, can only be used where the material will 

stand up for some distance without the support of the pipe. Quicksand will flow around the bit and even rise in the pipe, and in this 

material the pipe must be driven down to the bottom of the hole and 

kept ahead of the drill. If the bed of quicksand is not thick, the 

difficulty of drilling through it will be slight, but where beds 50 or 60 

feet in thickness are encountered, some of the greatest difficulties 

known to ·well engineers have to be met and overcome. 

When long and difficult strings of casing or drive pipe are to be 

withdrawn or" pulled" from a well, as on completing or abandoning 

it, a pipe ring (fig. 9 10 ) is placed over the upper end of the pipe; 

this ring grips the casing firmly by means of its corrugated iron 

wedges and is then subjected to upward pressure by specially de-

&igned hydraulic lifting jacks. (Fig. 9 11.) When short or easily 

pulled lengths are to be removed, wrought-iron elevators (fig. 9 12 ) 

are clamped to the upper end of the last length of pipe, are caught by 

a hook suspended from the derrick, and are tugged upward by means 

of pulley sheaves. 

Several machines for pulling casing are on the market. For pulling easing from abandoned wells they have the great advantage of 

portability, and they are cheaper and more efficient than a derrick 

erected over the well. 
56 WELL-DRILLING METHODS. 

PORTABLE DRILLING RIG. 

VARIATIONS IN CONSTRUCTION. 

Several modified forms of the standard outfit, called portable rigs, 

are made. These rigs are built in compact form, on heavy frames, 

and are usually mounted on wheels. Horses are commonly employed 

in moving these rigs, but in favorable localities a traction engine supplies power for the machine when in operation and hauls it when it 

is to be moved. A steam or gasoline engine is used, and the engine 

may or may not be mounted on the frame with the other machinery. 

In mode of operation and in the kind of tools used these portable 

rigs are like the standard outfit, but most of them are lighter and 

they can not be used to drill to as great depths. Certain parts of 

the machinery, such as the hoisting gear and sand reel, are usually 

placed within the frame, and are operated through either cog or 

friction-p·ower transmission. 

The difficulty of weight in transportation is one which the manufacturers have been working for a long time to overcome. Every 

part of such rigs has been carefully tested and the experience of 

operators taken into account, so that machines made at the present 

time represent the maximum strength with. the minimum amount of 

material, and any decrease in the weight of any part would mean a 

decrease in effectiveness and durability. The total weight of a 

portable rig is usually about 15,000 pounds, though lighter outfits 

may weigh only 5,000 pounds, and some of the heavier ones weigh 

20,000 pounds or more~ 

In most portable machines support for the hoisting sheave is provided, not by a derrick, but by a mast, which is erected over the front 

of the rig, and brings the sheave over the spot where the well is to 

be drilled. In hauling the machine from place to place the mast is 

tilted back over the machinery, as shown in Plate II. 

To make the portable rigs more compact the walking beam is 

made 2 to 6 feet shorter than the walking bea1n of the ordinary 

standard rig. The shortened ·stroke which results becomes a disadvantage only when the hole reaches considerable depth. In the first 

few hundred feet the stretch of the rope is so slight that the short 

walking beam is nearly as efficient as is the usual walking beam of 

the standard rig; at greater depths the total stretch of the rope is so 

increased that unless the stroke of the walking beam is correspondingly lengthened the machine will drill on the tools; that is, when 

the walking beam is coming up the tools will be going down. If 

the walking beam is properly adjusted, however, drilling may be conducted to a depth of 1,000 or 1,500 feet. Beyond 1,500 feet the stroke 

of most portable machines becomes so short as to make them less 

efficient than the standard outfit. 
U. S. GEOLOGICA L SURVEY WATER-SUPPLY PAPER 257 PLATE II 

PORTABLE DRILLING MACHINE, USING STEAM-POWER TRACTION . 

Show ing derrick folded , spudd1ng bar, etc . 
PORTABLE DRILLING RIG. 57 

A technical description of the details of each of the many styles 

of portable well-drilling machines can not be given in this report, 

and it would be obviously improper here to designate by name those 

supposed to be the best or those having manifest disadvantages. 

Each rig includes some device which makes it in certain respech:; 

f?Uperior to others~ but no portable well-drilling machine is perfect. 

Unfortunately the invention of a new device usually results in building a new machine, and the embodiment of all good devices in one 

nearly perfect machine is impossible on account of patents. 

The leading portable drilling machines are so fully ~escribed in 

the manufacturers' catalogues that a driller can readily note the 

important points and advantages of each style. Some rigs have 

special devices for rapid spudding, as spudding is in many wells 

carried to a depth of 100 feet, or even more, and forms so large a 

part of the sinking of wells less than 1,000 feet deep. One way of 

obtaining a spudding motion is shown in figure 8. Some rigs have 

devices to shorten the time for changing from drilling to bailing, such 

as variations in the form of the pitman, so that it need not be disconuected from t-he crank pin in changing from one operation to the 

other. Others have special devices for deep drilling. Several portable rigs are adapted to using self-cleaning or hollow-rod tools~ and 

one or two are fitted to operate hydra\].lic rotary and core-drilling 

tools. 

ADVANTAGES AND DISADVANTAGES. 

Most portable rigs are not intended for deep, heavy work and do 

not come into competition with the standard outfit, though of. late 

years heavy, semiportable rigs with a capacity of 2,000 feet or more 

have been built for oil drilling. Both portable rigs and the lighter 

styles of the standard outfit are used in drilling wells between 500 and 

1,500 feet in depth. . 

Portable rigs are often used in cleaning out oil wells, which are 

also cleaned by erecting derricks over them and stringing the tools 

as in beginning a well; but as the work involved in cleaning is not 

very great a lighter and cheaper outfit than the standard can be used 

to advantage. 

Portable rigs are also used in prospecting for gold in Siberia, Australia, Argentina, and South· Africa, and in drilling blast holes 

for large excavations such as the Panama Canal. 

The chief advantage of a portable rig is that it can be easily and 

cheaply moved after the well is completed, whereas a standard outfit 

must be torn down and rebuilt for use in a new location. 

In some localities, as in southern Illinois, where the country is flaf 

and the difficulties of transportation during the rainy season are great 

.on account of muddy roads, drillers with standard outfits are usually 
58 WELL-DRILLING METHODS. 

able to tear down and rebuild the derrick in a shorter time than 

would be required to haul a portable rig to a new location and set it 

up. Drillers near Casey, Ill., claim that they can set up a standard 

outfit twice and drill two wells with it in the same time that one well 

can be drilled with a portable rig. The standard derrick used near 

Casey is 60 feet high and is built of light timber in skeleton form, 

except in stormy weather. This out:(it will drill a hole 500 feet deep 

in about five days; a portable rig would consume ten to fifteen days. 

When made in this light form the standard rig is taken down in 

sections, each o£ which is placed on a pair of trucks and hauled from 

place to place more easily than a portable rig, which must be moved 

as a whole. 

Once in position the standard rig is preferable to the portable on 

account of its greater rigidity, the larger space it affords for handling 

tools, oiling bearings, and repairing broken parts, and the better 

protection it gives during stormy weather: The compactness of some 

portable rigs makes it difficult to oil or adjust the machinery while in 

operation without danger, or at least without great discomfort, to the 

workmen. The extra work o£ lifting large wrenches and drill bits to 

the drilling platform when adjustments are necessary is also very 

considerable. Breakdowns with a portable rig are annoying and 

expensive, as the driller must often send to the factory for the broken 

part; whereas most breaks i~ a standard outfit can be repaired by a 

local blacksmith or carpenter, or by the workmen themselves. 

With portable rigs the bits are dressed in the open, and there is no 

shelter for· men or tools from sun or rain. Shelter can of course be 

provided for both rigs, but more easily for the standard, since the 

derrick posts form a frame that needs only to be boarded in. Owners 

of portable rigs expect workmen to do without a shelter, but the shed 

is a usual part of the standard outfit. I£ a shelter always had to be 

built for a portable rig the extra labor required would leave little 

advantage in favor of this machine. The flywheel and gearing, 

however, are often protected in rainy weather by a lean-to. 

Much of the difficulty that has attended the use of portable maehines may be attributed to the fact that the men engaged to operate 

them have been aecustomed to standard outfits and are prejudiced in 

their favor. Drillers have been severely eriticised. by manufacturers 

and well owners because of this prejudice, asserting that every improvement devised was eondemned by the drillers because it was 

novel and at first somewhat difficult to manipulate. In a measure 

this is true, but it should be remembered that these men are trained 

in the oil fields of Pennsylvania, Ohio, Indiana, and West Virginia, 

where the standard outfit is largely or exclusively used, and, having 

slight knowledge of mechanics aside from that gained in actually 

operating standard outfits, they look with disfavor on portable rigs. 
POLE-TOOL METHOD. 

A man who begins his drilling experience with a portable rig is always enthusiastic over the machine and 

its possibilities. This is especially true of drillers of 

water wells ranging in depth from 400 to 500 feet. 

That portable rigs are adapted to a wide range ·of 

conditions is shown by their general use. In. drilling 

for water, oil, and gas they have been successfully employed in every part of the United States, and in drilling for water they are used in nearly every country 

in the world. 

PERCUSSION CORE DRILL. 

Within the last few years a percussion core drill, designed to obtain a core when prospecting coal and other 

relatively soft deposits (seep. 30), has been put on the 

market by a manufacturer of portable drilling machines. This drill is substituted for the ordinary drill 

after the hole has been sunk nearly to the material of 

which a sample is desired. 

The drill consists essentially of a hollow tube or bit 

stem armed with a toothed cutting bit, a core barrel, 

and a weighting bar. The teeth of the bit are "set" 

alternately in and out, like those of a hand saw, so as 

to give clearance to the drill on the outside and to the 

core within. The core barrel is a tube, about 4 feet 

long, that slides within the bit stem. It has a split 

ring near the bottom, which grips the core when the 

tools are withdrawn. As sinking progresses a weighting bar forces the core barrel down over the core and 

protects it from abrasion. (See fig. 10.) 

The chief advantages claimed for the attachment 

are its adaptability to the ordinary portable drilling 

outfit; the large core yielded, as the device is made 

chiefly for 5~ or 6 inch tools; the ease and rapidity" of 

withdrawing tools, as they are on a cable, not on jointed 

rods; and special adaptation to taking samples of very 

soft material. It is not intended for work in very hard 

rock nor in localities difficult of access. 

POLE:-TOOL METHOD. 

GENERAL FEATURES. 

' 59 

The pole-tool or wood-rod method of well drilling 

is old and, in some respects, rather primitive, repre- FIG.lO.-Percus- senting an early stage in the development of churn sion core drill. 
60 . WELL-DRILLING METHODS. 

drilling. It differs from the standard method chiefly in us1ng 

wooden rods instead of a cable for operating the tools. 

Previous to the introduction of hemp cable the pole-tool outfit was 

much used in England and France, where it is still employed to some 

extent; but in the United States it has been larg_ely superseded by 

cable rigs. It is, however, still used in this country for sinking water 

wells in certain regions, especially in the area between Illinois and 

Montana and north of Kansas and Colorado, where the great depth 

of the wells and the large amount of water encountered make the 

retention of wood rods advantageous in drilling wet holes. If a portion of the hole is drilled dry, a cable is attached and drilling is conducted as with the standard outfit; but the friction of 1,200 or 1,500 

feet of hemp rope in as many feet of water so greatly reduces the force 

of the blow on the rock that a pole-tool outfit may be more advantageous. 

When a cable rig is used in a hole containing considerable water 

the friction may be reduced by tarring or oiling the rope so that the 

fibers can not spread. This treatment, however, affords only a temporary remedy and but slightly decreases the friction of the rope. By 

using wooden rods the friction is greatly reduced, and the drill can be 

operated much more efficiently. 

In the oil and gas fields of Pennsylvania and Ohio it is desirable 

and often necessary to keep water out of the hole·, either because the 

operator can drill faster in a dry hole or because he must exclude 

water from the oil sands; but in North and South Dakota, Wisconsin, 

and Illinois, where the pole-tool outfit is in use, the driller is drilling 

for water and may desire to retain all flows he may pass to supply 

the completed well. A cable rig could be satisfactorily used only 

by casing out the water, drilling the hole to the depth necessary to 

guarantee a sufficient supply, and then drawing the casing or perforating it to allow the water access to the well. Experience has 

shown that under ordinary conditions the expense of the casing and 

of the increased labor required in drawing or perforating it, when 

drilling water wells with the standard outfit, exceeds the cost of 

drilling with the pole-tool outfit, in spite of the extra labor involved 

in the actual drilling with the latter. 

The necessity of maintaining the initial diameter of the rods prevents drilling a hole as small as that which can be drilled by means 

of a cable. If the hole is full of water and its size is decreased to 

3 or 4 inches, drilling is greatly impeded by the long column of water 

that rises and falls with each stroke of the drill. The diameter of 

the hole, therefore, can not he reduced below the size which gives 

ample clearance between the rods and the well wall. In the pole-tool 

n1ethod the drill falls on the rock at the bottom of the hole as a dead 
POLE-TOOL METHOD. 61 

weight, and a springing blow can not be struck as when drilling with 

a cable. This reduces the speed of drilling considerably. 

OUTFIT. 

A derrick about 60 feet high and 16 feet square at the base is used 

with the pole-tool outfit. It resembles the standard derrick in most 

respects and requires about ten days to set up and two to four days 

to take down. 

The string of tools of the pole-tool outfit, like that used with cable 

outfits, consists of socket, jars, auger stem, and drilling bit. The rods, 

which are substituted for the rope, are 2 to 3 inches in diameter. 

Each length of rod consists of two 18-foot pieces, spliced together and 

reinforced at the joint by irons. (See fig. 11, 0.) 

Jars are used to prevent the weight of the rods from coming on 

the drill, and also to prevent the crushing of the rods under their 

own weight. Before the invention of jars this battering and crushing was a constant source of trouble in well drilling with rods, and was 

the chief cause of the numberless fishing operations of early days. 

The jars, therefore, ca.,n not be discarded frmn pole-tool outfits as they 

~ometimes are from cable outfits. 

As with the standard outfit a walking beam is used, and the length 

of stroke is controlled by changing the length of the crank; but a 

ratchet on the walking beam, operated by a crank and lever within 

easy reach of the driller is used instead of a temper screw for feeding 

the drill. (See fig. 11, A.) A chain runs :from the drum of the 

ratchet over the end of the walking beam and is connected with the 

rods by means of a swivel. 

DRILLING OPERATIONS. 

While drilling, the tools are constantly rotated so as to keep the 

joints on the rods tight and the drill hole ·round, for there is not 

sufficient natural torsion in the rods, as there is in a cable, to keep the 

drill from striking twice in the t,ame place. 

In drawing the rods, the whole string is raised by means of a hemp 

cable with swivel attachment, operated through a pulley at the top 

of the derrick. When the first joint appears above the top of the 

well head an assistant sets the square end of the joint iron into a 

wrench laid in the socket of the wrench block. (See fig. 11, B.) 

The wrench tightly fits this socket in the block and is prevented from 

turning when the rods are turned by a small iron post, the arrangement serving the function of the wrench and floor circle used in the 

standard outfit. With another wrench a second workman unscrews 

the swivel by which the raising cable has been attached to the upper 

rod, and this rod is unscrewed from the one below and set at one 
62 WELL-DRILLING METHODS. 

side of the derrick. The wrench that is fitted on the square end of 

the second rod previous to detaching the first length prevents the 

whole string of rods and tools from dropping into the bottom of the 

well when the first length is removed. The swivel is then lowered 

and screwed to the upper end of the second length of the rods. These 

are drawn up so that the square joint iron of the third length fits 

FIGURE 11.-Canadian pole-tool outfit : A, Side elevation; B, wrench block ; C, drill rod. 

into the wrench, and the whole string of rods and tools is held by it 

while the second joint is being unscrewed. In the same manner the 

tntire string of rods is raised and taken apart. This operation makes 

it necessary for one workman to be in the derrick about 36 feet 

above the surface of the ground, but in this position he is able to 

help the man at the well head in steadying the rods and setting them 

to one side, and in guiding the descent of the lifting swivel. 
POLE.-TOOL METHOD. 63 

In raising and lowering the tools the men work rapidly, though 

two of the three men needed in operating the outfit are busy only during the time that the drill or bailer is being raised or lowered. There 

appears to be great waste of time in this method of drilling, especially 

in bailing the cuttings, .for which purpose a steel cable might w~ll be 

used when the drillings are thin, as the bailer can be made of a size 

and weight to cause it to sink to the bottom of the well without 

difficulty. At least an hour is spent in raising the drill out of the 

hole, lowering the bailer, redrawing it, and resuming operations with 

the drill. Each one of these four operations involves the unscrewing 

and screwing up of rods in 36-foot lengths, and in a hole 1,000 or 

1,500 feet deep the labor required is very great. Expert drillers can 

raise and lower the rods at the rate of 100 feet a minute, and ordinary 

workmen at the rate of 60 to 75 feet a minute. 

In drilling some wells bailing does not occupy so large a part of the 

time. In artesian wells, for example, the cuttings may be carried 

away by the pressure of the water. The head at shallow depths may, 

however, be insufficient to accomplish this, but it may be greatly 

increased when the hole is deepened to coarser water-bearing material, 

and bailing may then be discontinued. In creviced rocks the drillings may be carried off by the downward and outward movement of 

the water. 

When lowering the rods into the drill hole care should 'be taken to 

keep the lowest joint-that connecting the rods with the jars-looser 

than any of the other joints of the string, so that if the drill sticks 

fast in the rock th~ driller may unscrew the rods and remove them 

:from the hole without difficulty. 

The drill may then be loosened by a fishing spud and the rods lowered into the hole, fastened to the pin of the jars, and the tools withdrawn. Occasionally, however, the lowermost joint becomes tight, 

especially when drilling in rocks of irregular structure or rocks in 

which there are many crevices. In an accident following such a 

tightening of the rods on the drill it is sometimes necessary to lower 

a knife into the well and cut away the rods just above the drill. 

Then, after the tools have been spudded loose, they may be withdrawn by a slip socket. 

Loss of tools-the most common accident in using pole-tool outfitsis due to failure of the man at the well head to catch the square 

shoulder at the end of the rod with his wrench, as a result of which 

the tools drop to the bottom of the well. The rods are usually broken 

by this accident and have to be removed piece by piece by means of 

spears, slip sockets, and other devices. Sometimes the buckling and 

breaking of the rods in the hole prevents their withdrawal and the 

hole must be abandoned. 
64 WELL-DRILLING METHODS. 

A drill in a well in which the driller desires the water to enter from 

all parts of the hole may encounter caving rock between two waterbearing beds. An attempt to shut off the caving rock by casing from 

the surface to the rock would shut out the water above it or .would 

necessitate perforating the casing at· the level of the upper water. 

Caving is therefore prevented by lowering into the well a piece of 

casing long enough to cover the caving rock. The hole is then reduced in· size and drilling is continued. In the vicinity of Chicago 

caving rock is found at a depth of about 1,000 feet. It does not 

usually carry much water and the little it contains is under slight 

head. The short piece of pipe, therefore, stops the inflow of material 

and allows drilling to proceed. 

Where a pole-tool outfit encmmters quicksands it is almost worthless because of the great amount of time required in withdrawing the 

tools and the rapid inflow of the sand, and it :QlUSt therefore be supplemented by rotary appliances. 

SELF-CLEANING OR HOLLOW -ROD METHOD. 

OUTFIT. 

The self-cleaning or hollow-rod method of well sinking includes 

the essential features of the percussion methods, but differs in combining in one operation the breaking up and removal of the material. 

The tools consist of a string of pipe with screwed couplings, usually 

of special manufacture to insure strength and durability, with a 

water swivel at the upper end and a drill bit at the lower end. Because of this use of joints of pipe instead of a drilling cable the 

machine is often called the hollow-rod outfit. 

The water swivel is. essentially a swiveled gooseneck that allows 

the water and drillings to be discharged from the pipe in a constant 

direction and still permits the drill pipe to be rotated. In the usual 

outfits of this class the pipe is li or 2 inches in diameter and the 

drill is 2! to 4 inches across, though the hole may be enlarged by 

using an expansion bit. 

The drill bit has one or more holes at its upper end and a flap valve 

that allows water and drillings to enter the pipe and be lifted automatically to the surface. Blind valves are also usually placed at 

intervals within the pipe to relieve the lower valve of the weight of 

the entire column of water and drillings. 

The oiltfit usually includes a mast that is held upright by guy lines 

and supports a sheave pulley over which passes the cable used in 

operating the tools. In many of the outfits the device for lifting 

and dropping the tools consists simply of a pulley and reel. The 

cable is fastened to the upper end of the string of hollow rods, passed 

over the sheave pulley, and one or two turns are taken around a 
SELF-CLEANING ()R HOLLOW-ROD METHOD. 65 

hoisting reel. As the reel is continuously revolved by engine or other 

suitable power the drill may be raised and let drop by alternately 

tightening and loosening the rope on the reel. Self-cleaning tools 

are also commonly used with portable ·rigs, being operated by the 

spudding attachment. 

The "Ohio" machine is a self-cleaning outfit that has been fitted 

with a special operating device. In this outfit the rods are gripped by 

jaws and lifted by power transmitted through a crank and pitman. 

At the upper end of the stroke levers attached to the jaws are tripped, 

the tools are released and fall freely, and are caught up again by the 

jaws, on the rebound of the blow. 

DRILLING OPERATIONS. 

-In drilling by the self-cleaning method water must occasionally be 

poured into the well until it is encountered in sufficient quantity for 

the needs of drilling. The drilling operation is continuous, for as 

the drill is alternately raised and let fall the jumping or pumping 

action forces water and .drillings into the drill rods and upward to the 

surface. This action resembles that of a hydraulic ram, but in the 

drill the sudden compression required to open the valve is obtained by 

the drop of the tools instead of by the fall of a water column, as in 

the ram. 

The efficiency of the pumping action of the drill depends on the 

~hape of the drill shoulder, which for best results should have a circular cross section a little smaller in diameter than the width of the 

flat cutting edge, from which it should flare outward sharply so as 

to obtain the greatest effects of compression in opening the valves and 

forcing the drillings upward. 

The pipe is slowly rotated during drilling, so that the drill will not 

strike twice in the same place and so that it will spall the rock off in 

flakes and not break the material simply by striking a straight blow. 

Ordinary casing with screw couplings is commonly used to case off 

caving material and excessive water, and is sunk as drilling progresses 

by a drive weight attached to the drill rods, whose weight is thus 

made to aid in the driving. 

A properly tempered bit will be sharper when it is taken out of the 

hole than when put in, for the wear comes mainly on its edge and 

tends to reduce its gauge. When the approximate depth of the hole 

to be drilled is known, bits may be run long distances. So long as .. 

they are larger than the joints on the rods they will not stick as will 

cable bits when worn, for the vibration of the rods keeps them free. 

M~ny ~holes 100 to 150 feet in depth have been drilled with one bit 

without removing it from the hole. "\Vhen a bit is used too long, 

hom'¢-er, the hole must be reamed when a bit of standard gauge is 

substituted for it. 

65275°-W s P 257-11-5 
66 WELL-DRILLING METHODS, 

USES. 

The self-cleaning outfit is admirably adapted to sinking water 

wells of small diameter in sand, clay, shale, soft limestone, and other 

easily penetrated materials. Concerning its use for this purpose, 

Veatch says: a 

The important feature of this rig from a water standpoint and the one which 

makes it of peculiar utility for sinking water wells in the Coastal Plain region 

is that it is impossible to pass a water-bearing stratum, no matter how small, 

without being aware of its presence. 

The self-cleaning drill is also used extensively in prospecting for 

coal in Ohio and for lead and zinc in Wisconsin and Illinois. In 

coal prospecting a solid drill and cable are often used in drilling 

much of the distance down to the coal bed, and the self-cleaning tools 

are then used to determine the thickness of the bed. A larger bit 

than common is usually employed for this purpose, as it takes larger 

and more determinative samples. The casing can be easily withdrawn 

from prospect holes by driving it upward. 

CALIFORNIA OR STOVEPIPE METHOD, 

INTRODUCTION. 

For sinking water wells in the unconsolidated alluvial deposits of 

portions of California a method is used which, on account of its 

distinctive character, is called the California or stovepipe method. 

It is also sometimes called the mud-scow method, because of the instrument by which drilling and bailing are accomplished. 

The following description is adapted from two articles by C. S. 

Slichter 0 and by I. N. J{napp.c 

RIG. 

The rig consists of a horizontal rectangular frame to which is 

hinged a derrick about 34 feet high, held vertical by two diagonal 

braces from the frame to the derrick. The walking beam-a marked 

feature of this rig-is carried at the top of the derrick. The bottom 

of the derrick is hinged to a saddle piece resting on two coiled car 

springs, which in turn rest on a heavy crosspiece bolted between the 

sides of the frame. 

The hoisting reel and other machinery are placed on the framework just back of the derrick, and at the farther ~nd are the· engine 

"Veatch, A. C., Geology and underground·water resources of northern Louisiana and 

southern Arkansas: Prof. Paper U. S. Geol. Survey No. 46, 1906, p. 101. 

b Slichter, Chas. S., Field measurements of the rate of movement of underground water: 

Water-Supply Paper U. S. Geol. Survey No. 140, 1905, pp. 98-103. 

c Knapp, I. N., Drilling wells i~ ~Qft and unconsolidated !QrW~tious: Steveus Itu;;t. 

Indicator, vol. 22, 19Qti, pp. 17-30, 
CALIFORNIA OR STOVEPIPE METHOD. 67 

and hydraulic pumps. When steam power is used, the boiler is 

separate and is placed at one side, near the engine. When the 

machine is to be moved, the mast is swung back on its hinges, with its 

I I 

Jaw rope socket 

quare shank bolt in square hole 

Box and tongue sub 

Fishing jars 

24"stroke 

Pin and tongue sub 

Mud scow 

14 to 18 ft.long 

0 

.... 

Casing yoke 

lll

.tl "' 

CIS 

a. "' 

-

~ -

I 

Drive shoe 

2 

3 

FIGURE 12.-Parts of California or " stovepipe" outfit. 1, String of tools; 2, casing, 

drive shoe, etc. ; 3, perforator for slitting stovepipe casing. 

top resting on an upright at the rear end of the rig. Jackscrews are 

then placed under the sills and the whole machine is raised sufficiently 

to allow wheels to be slipped onto axles bolted to the sills. 
68 WELL-DRILLING METHODS. 

In drilling, the walking beam is given a reciprocating motion by 

a wooden rod attached to its rear end and to the driving machinery. 

The tools are suspended from its forward end by a cable, usually a 

half-inch wire rope. The string of tools below the socket by which 

it is attacheu to the cable consists of a box and tongue sub, to which 

is screwed a pair of jars of the usual type, and below the jars is 

another sub to which is fastened the sand bucket or mud scow. (See 

fig. 121.) The sand bucket is similar in shape to that used with 

the standard outfit, and. has a flap valve at the bottom, like that of the 

standard sand bucket; but it differs in being connected to the tools 

above by a knuckle joint that permits easy dumping, instead of by a 

bail, and at the bottom it carries a cutting shoe simila~ to that used 

on the bottom of a string of casing. For dr:illing in clay this shoe 

may be modified by a straight chisel-like bit extending as a diameter 

across it. 

CASING. 

The casing used in this method of drilling is made of lap-riveted 

cylinders of sheet iron or steel, usually of No. 10 to No. 14 gage, '24 

inches long and 6 to 14 or 16 inches in diameter. (See fig. 12 ~) 

These short joints are known as stovepipe casing. The pieces of sheet 

metal may be taken to the field flat and riveted there, but usually the 

riveting is done at the shops and the ends are also turned square and 

true. Two sizes are used for the string of casing, one of which just 

slips within the other, so that the joints of one may be adjusted to 

fall midway between the joints of the other. The sections are added 

one at a time as sinking proceeds, each 2-foot joint adding only 1 

foot to the length of the string, and the outer and inner sections are 

united simply by denting with a pick. This casing is water-tight, 

but for water wells it is not necessary that it should be. 

Stovepipe casing may be started from a properly recessed drive 

shoe, but it is easier to begin a well straight and keep it plumb by 

using a starter, as with other casing. This starter is 15 or 20 feet 

long and may be made of sections of stovepipe casing, often of three 

thicknesses, riveted together, or of a joint of heavy lap-weld casing. 

At the lower end is an annular steel drive shoe. (See fig. 122.) 

The casing is usually sunk by two or more hydraulic jacks whi.rh 

are buried in the ground and anchored to two timbers, about 14 

inches square and 16 feet long, planked over and buried 8 or 10 feet 

deep. In the smaller sizes of shallower wells the casing is sometinfes 

forced down by two steel !-beams or railroad rails, arranged as powerful levers. 

DRILLING OPERATIONS. 

After the outfit has been set up and the starter and hydraulic jacks 

have been sunk in position, the string of tools is lowered and drill-
CALIFORNIA OR STOVEPIPE METHOD. 69 

ing begins. In this process the sand bucket or mud scow, as it is 

worked up and down by the walking beam, acts both as a drill and a 

bailer. In ordinary material it is rotated to loosen the sand and 

gravel from inside of the casing, and when it is drawn up to be 

emptied the bucket is manipulated in such a way that the weight of 

the jars and connections assist in the dumping. 

The driller stands at the front of the rig and has complete control 

of the engine, hydraulic pump, jacks, and clutches that cause the tools 

to work up and down or be hoisted. 

Water is necessary for the drilling operation, and must be added 

at the top of the casing until it is struck in the hole. The sand 

bucket must not be run until it is filled to overflowing, for the excavated material may spill over between the bucket and the casing 

and stones and gravel may become jammed between them and cause 

a serious fishing job. Bowlders that lie in the way are usually worked 

to one· side of the casing shoe and passed by, by drilling on them 

with the bucket, which takes up the finer material; or if the bowlders 

are unusually difficult to pass, they are broken to pieces by a drill 

that is substituted for the sand bucket. 

In drilling in quicksand or caving ground it is necessary to keep 

the water level about the same inside the casing as on the outside, 

and also to keep the casing even with or ahead of the excavation made 

by the bucket. In very soft ground a hole larger than the casing is 

apt to form, thus making a cavity outside of the casing, and falling 

ground from the top of such a cavity is liable to crush the casing. 

PERFORATION OF CASING. 

A record of the material encountered in sinking the well is kept, 

and after the well has been sunk to the required depth a cutting knife 

is lowered into it, and vertical slits are cut in the casing at such 

water-bearing strata as may be most advantageously drawn upon. 

A ·well 500 feet deep may have 400 feet of screen-that is, perforated 

casing-if the circumstances justify it. 

One style of perforator for slitting stovepipe casing is shown 

in· figure 123 , the perforator being shown in cutting position with 

knife extended. It is handled with a 2-inch standard pipe with 

-!-inch standard pipe inside. In going down and in coming out of 

the well the weight of the !-inch line of pipe holds the point of the 

knife up. When ready to "stick" the !-inch line is raised; then by 

raising slowly on the 2-inch line with the hydraulic jacks, cuts are 

made three-eighths of an inch wide and 6 to 12 inches long, according to the material at that particular depth. Another style of perforating knife has a revolving cutter that punches five holes at each 

revolution of the wheel. This kind of perforator is called a" rolling 

knife." 
70 WELL-DRILLING METHODS. 

ADVANTAGES. 

The advantages of the California method of well construction for 

use in unconsolidated deposits have been summarized by Slichter as 

follows: a 

1. The absence of screw jofnts liable to break and give out. 

2. The flush outer surface of the casing, without couplings to catch on bowlders or hang in clay. 

3. The elastic character of the casing, permitting it to adjust itself in direction and otherwise to dangerous stresses, to obstacles, etc. 

4. The absence of screen or perforation in any part of the casing when first 

put down, permitting the easy use of sand pump and the penetration of quiek· 

sand, etc., without loss of well. 

5. The cheapness of large-size casings because made of riveted sheet steel. 

6. The advantage of short sections, permitting p.se of hydraulic jacks in 

forcing into the ground. 

7. The ability to perforate the casing at any level at pleasure ·is a decided 

advantage over other construction. Deep wells with much screen may thus be 

heavily drawn upon with little loss of suction head. 

8. The character of the perforations made by the cutting knife are the best 

possible for the delivery of water and avoidance of clogging. The large side of 

the perforation is inward, so that the casing is not likely to clog with silt and 

debris. 

9. The large size of casing possible in this system permits a well to be put 

down in bowlder wash where a common well could not possibly be driven. 

10. The uniform pressure exerted by the hydraulic jacks is a great advantage 

in safety and in convenience and speed over any system that relies on the 

driving of the casing by a weight or ram. 

11. The cost of construction is kept at a minimum by the limited amount of 

labor required to man the rig as well as by the good rate of progr~ss possible in 

what would be considered in many places impossible material to drive in, and 

by the cheap form of casing. 

HYDRAULIC ROTARY METHOD. 

DEVELOPMENT. 

The hydraulic rotary method of drilling has been used for many 

years for sinking shallow water wells in fine-textured, unconsolidated 

materials, but it attained prominence in deep-well drilling in 1901, 

when it was first ·successfully used in sinking oil wells in the Spindle 

Top field near Beaumont, Tex., where other methods of drilling had 

failed, and it has since been a great factor in the development of the 

Texas fields. Its successful use in that region and the consequent 

great improvement in the machinery employed has led to its increasing use where soft materials are encountered. Sinking is accomplished by the rotation of an annular toothed shoe on the bottom of 

the string of casing. 

a Watet·-Supply Paper U. S. Geol. Survey No. 140, p. 101. 
HYDRAULIC ROTARY METHOD. 71 

OUTFIT. 

With the hydraulic rotary outfit a derrick similar to that of the 

standard rig is used, but the machinery and tools are unlike those of 

percussion outfits. The principal parts of the machinery are a revolving table or whirler, two hydraulic pumps, and boiler, engine, and line 

shaft to furnish power. 

The revolving table is a heavy rotating device, set on tool-steel 

rollers, that grips the casing firmly and permits it to be revolved and 

yet allows it to be gradually lowered as sinking progresses. The table 

is revolv~d by means of bevel gearing connected with the line shaft 

and controlled by a clutch and lever. 

The hydraulic pumps, which supply water for drilling, are capable 

of developing a pressure of 125 to 175 pounds to the square inch. As 

the water used is very muddy the pumps are made with but 6 to 10 

valves, whereas if the water were clear 20 to 24 valves would be used. 

The valves also fit more loosely than in ordinary pumps, so as to 

reduce the abrasion produced by the sediment. Only one pump at a 

time is in use, but to permit packing of the valves and to provide for 

accidents and emergencies two pumps are always installed. In many 

plants two boilers· are also installed for similar reasons. The pump 

that is in use is connected with the top of the casing through a hose 

line and water swivel similar to those in the self-cleaning outfit, but 

larger, so as to allow the continuous pumping of water into the casing 

while the latter is being rotated. A back-pressure .valve is usually 

inserted in the gooseneck at the upper end of the swivel, to relieve 

pressure on the hose. Two swivels are needed, one being attached to 

the joint of casing to be next added to the string, while the other is 

In use. 

The engine is connected by a link drive chain to the line shaft, which 

also furnishes power to the revolving table and to a hoisting drum and 

reel. 

Thin mud or slush plays an important part in drilling, and a slush 

pit is an essential accessory of the outfit. This pit is usually dug 

near the derrick, on the same side as the pumps, and is about 40 feet 

long, 15 feet wide, and 3 or 4 feet deep, though the size varies with 

convenience and the preference of the driller. A ditch where sand 

may settle out of the mud is cut from the well circuitously to the slush 

pit, from which hose or pipes lead to the ·pumps. (See fig. 13.) 

DRILLING OPERATIONS. 

· Drilling is accomplished by rotating the entire string of casing, 

on whose lower end is a toothed cutting shoe. The rotation under 

heavy pressure breaks off and grinds up particles of the material that 
~: :;· ~;:_-:-_:~-~-=­

. ; : :.- :_.:·-~:. ~.. =~ 

-r~ Slush pit 

FIGURE 13.-Hydraulic rotary outfit ; plan and elevation. 

-::r 

to 

~ l;j 

~ I 

t::j 

ttl 

1-t 

~ 1-t 

z 

Q 

~ t;t 

...., 

~ 

g 

!Jl 
HYDRAULlC ROTARY METHOD. 78 

is being penetrated, and they are carried to the surface by water that 

is pumped down the casing under pressure and rises on the outside, 

between the casing and wall of the hole. Only one casing, that which 

is being revolved, is used, for as the muddy water escapes upward it 

puddles the side of the well so that the material stands alone. 

If a bed of clay is encountered, the water used in drilling is kept as 

clear as possible and is not drawn from the slush pit, for the clearer 

the water is when introduced the greater is its capacity to uphold 

and move particles of earth, and the clay is sufficiently compact to 

make a wall that will not cave. In penetrating sand and gravel 

layers, clay often has to be added t0 the slush pit, so as to make a thin 

mud that will plaster up these beds .and prevent them from caving 

and also prevent the escape of drill water into them. In some oil 

fields a trough with revolving paddles, called a mud mixer, is used to 

prepare the slush of proper consistency for plastering up sandy layers 

and also for closing gas pockets. 

A pressure gage .enables the driller to feed the casing into the 

hole with uniform pressure. The casing must be lowered with care, 

for if it is fed too fast the hole may become clogged by failure of the 

pumps to raise the outside column of water and carry up the drillings. 

Many clays are so compact and dry as to resist strongly the action 

of the water, and if the casing is fed too rapidly a core forms within 

it, reducing the size of the opening through which the water must 

pass, and correspondingly increasing the pressure exerted by the 

pumps. This difficulty may be obviated by fastening across the end • 

of the rotary shoe a bar that will cut the core to pieces as rapidly as 

the shoe is fed into the clay. 

When the casing has been sunk so that its top is near the revolving 

table, another length of casing to whose upper end.the second water 

swivel is attached, is elevated by means of the hoisting reel so that it 

can be screwed onto the last length used. The first water swivel is 

then unscrewed, the new length of pipe is coupled on, and the hose 

connected to the water swivel at its upper end. This operation requires only a few seconds of the skillful workmen's time, and drilling 

proceeds with scarcely any interruption. To prevent the drenching 

of the men during the attachment of the water swivel, the pipe 

couplings are sometimes fitted with back-pressure valves. 

It is essential that the pump be kept going constantly, otherwise 

the drillings will settle in the bottom of the hole and "freeze" the 

pipe fast. Should drilling cease· at any time the water circulation 

must be kept up if possible, as slight cavings of material will cause 

the pipe to become clogged. 

One size of casing is carried down until the friction of so much 

pipe against the wall of the hole renders its turning difficult, or it 
74 1

WELL-DRILL1NG METHODS. 

I 

becomes "frozen," o~ stuck fast, from some other cause. A smaller 

size is then used until it in turn becomes fast. When it does become 

necessary to withdraw the rotary casing to change a shoo or put in 

a well £asing, the driller always risks a caving hole where the wall 

is not protected by casing; but if the wall of the hole is thoroughly 

pudd!ed the risk is not great, and often one may see ·drillers in the 

oil regions of Texas pull 700 or 800 feet of casing, the whole section 

of loose sands and clays standing unsupported. 

SPECIAL OPERATIONS. 

In penetrating firm material it is sometimes necessary to employ 

a rotary drill bit instead of the rotary shoe. Two styles· of bit for 

this purpose are in general use-the diamond-shaped and the fishtail. 

The diamond-shaped is usually first employed, and the fishtail afterwards used for reaming or enlarging the hole. These bits are 

nsed on a smaller casing than that which is employed with the 

rotary shoe, and slip down inside the larger casing. In hard rock 

chilled shot or other abrasive may be used as in the shot method, 

described on page 86. 

For fishing operati~ms, which are sometimes rendered necessary by 

the twisting off of the casing, tools are used that do not differ greatly 

from those employed for similar purposes in percussion drilling. 

If the twisted-off portion is short, however, it may be possible to pass 

it by using a diamond-shaped bit and "sidetracking" or drilling 

past it. 

On completing an oil well by the rotary method it is best to withdraw the casing and replace the toothed rotary shoe by an ordinary 

drive shoe, for it is difficult to make a water-tight joint at the bottom if the toothed shoe is left in the well. As in the percussion 

methods of oil-well drilling, the drive shoe is usually set in the formation that is known from other wells in the same locality to overlie 

the oil-bearing sands. Drilling is then continued inside the casing 

for the remaining few feet or yards to the oil sands, and a smaller 

string of casing with a strainer at the bottom is lowered to the oil. 

Packing is accomplished, as in other methods of drilling, by seed 

bags, cement, or special packers. A packer called a boot leg is also 

frequently used. This is a slightly tapering leather sleeve somewhat 

larger than the casing. It is slipped over the casing and its lower 

(smaller) end is tied fast to the casing a short distance a hove the 

strainer. The mud remaining about the casing settles into the open 

upper end of the boot leg and thus fills and packs the space between 

the casing and the side of the hole. 

Many water wells sunk by the hydraulic rotary method are difficult 

to screen because of the depth at which the operation is conducted 

and the fineness of the material. A method in use. is to puddle the 
JETT!NG METHOD. 15 

-wall of the well at the water-bearing layer, set the screen, and draw 

the casing to the top of the screen. By pumping heavily for a few 

hours the pores of the puddled water-bearing sand are partly reopened, but the method has the defect of leaving the water-bearing 

layers more or less clogged by fine material. A more difficult but a 

better and more common way of screening is to sink the screen below 

the casing by forcing a hole down by a jet of water, the wash pipe 

being run ahead of it. A packer or lead seal is t.hen inserted at the 

point where the top of the screen joins the well casing to prevent 

material from rising over the top of the screen and _filling it. 

ADVANTAGES AND DISADVANTAGES. 

An objection to the hydraulic rotary method for drilling water 

wells has been made by some engineers, who claim that the driller 

often seals off water by puddling, and that the location of the waterbearing stratum must be known before drilling begins, otherwise it. 

will be passed through without the driller being aware of its presence. But operators of hydraulic rotary outfits claim that it is very 

easy to tell when a water-bearing layer is reached, as the gage shows 

a sudden decrease of pressure. This is true if the head of the water 

encountered is considerably beneath the level of the surface, but if the 

head is close to the surface-that is, if the water is nearly if not 

quite artesian in the sense that it will flow at the surface-the pressure will remain nearly the same and it will be impossible to tell 

. that a water-bearing layer has been encountered. 

The hydraulic rotary method is very rapid for drilling in loose 

material where the drill may descend continually. At Cor~icana, 

Tex., 1,065 feet were drilled through clay and marl in thirty-two 

hours. Both method and machinery have been rapidly developed 

through extensive use in the Texas oil fields, and as the method becomes better known it bids fair to. supplant others in use for lighter 

jobs. The method will, however, never supplant the jetting and selfcleaning methods for shallow work where only a cheap, light rig is required, any more than the heavy standard oil-well outfit will supplant portable rigs for drilling shallow wells; but for wells about 

1,000 feet deep, in soft, fine-grained materials, it will in time be almost 

exclusively employed, especially as the number of drillers who understand its operation is rapidly increasing. 

JETTING METHOD. 

OUTFIT. 

In the jetting method of well sinking the material is both loosened 

and carried to the surface by water under pressure. 

The principal parts of the outfit are a force pump and water swivel, 

drill pipe, nozzle or drill bit, casing and drive weight. 
76 WELL-l>RlLLlNQ METHODS. 

IIand-pow.er jetting outfits are made in several styles which differ 

chiefly in the arrangement for driving the casing. One outfit uses a 

block and tackle for raising and letting drop a weight of 200 pounds 

or more; another uses a lighter weight which is lifted directly by 

hand. Some outfits require a light derrick and working platform; 

others are operated from the ground. In a light hand-power rig 

like that shown in figure 14 the casing is about 2! inches in diameter and the drill.pipe about 1 inch. The larger machines have a 

mast and hoisting sheave and use engine power for handling the 

casing and drive ~eight and for working the pump. 

DRILLING OPERATIONS. 

In the jetting method water is led into the well through a pipe 

of relatively .small diameter and forced downward through the drill 

bit against the bottom of the hole. The stream of water loosens the 

material and.the finer portion is carried upward and out of the hole 

by the ascending water current, as in the hydraulic rotary method. 

During drilling the drill pipe is turned slowly to insure a straight 

hole. 

Casing is usually sunk as fast as drilling proceeds. In the softer 

materials, by using a paddy or expansion drill (fig. 144

a--4b) a hole 

may be made somewhat larger than the casing, which may be 

lowered a considerable distance by its own weight. Ordinarily, however, a drive weight is necessary to :force it down. As a rule one size 

of casing may be employed for the entire depth of the well. It is 

usually difficult to drive a single string of casing beyond 500 or ()00 

feet by this method, and i:f the well is sunk much deeper, a smaller 

size must be used. In fine-textured, clayey or loamy material the 

hole may often be jetted down to the full depth required and the casing inserted afterwards, for the wall of the hole becomes puddled by 

the muddy water and the vibration of the drill pipe against it, so that 

it will stand alone, like the wall o:f a well drilled by the hydraulic 

rotary method. 

When drilling with a light rig, hard layers may be penetrated by 

using a drill bit on the drill pipe, and raising and dropping the pipe 

so as to strike blows as in the percussion methods. In this operation 

a blind valve is usually inserted in the drill pipe near its bottom to 

prevent drillings from entering and clogging the pipe. With a 

heavier rig, equipped with mast and hoisting sheave, a cable and 

small drill may be used for penetrating locally hardened layers that 

do not readily yield to the water jet. · 

USES. 

The jetting method affords a rapid and cheap means of sinking 

small water wells in comparatively fine-grained, unconsolidated rna-
JETTING METHOD. 77 

5 

1 

FIGURE 14.-Jetting outfit. 1, Simple jetting outfit; 2, jetting process; 3, common 

jetting drill ; 4a,b, paddy or expansion drills ; 5, drive shoe. 
78 WELL-DRILLING METHODS. 

terials and has the advantage of being easily taken from place to 

place. A fundamental disadvantage is that the nozzle or bit requires 

considerable water for its operation, and in some localities this requirement is a serious obstacle to the use of the method. 

The jetting method is much employed for putting down wells in 

the Atlantic Coastal Plain and in some of the valleys of the arid 

West that are deeply fill~d with alluvium. In the Coachella Valley 

in southeastern California the method has been very successfully used 

in sinking wells for flowing artesian water. Most of the wells in this 

region are 400 to 500 feet deep and about 4 inches in diameter, and 

not uncommonly a well may be sunk, cased, and cleaned in two days. 

The method is also used in a few localities in mining kaolin. An 

iron pipe, 4 inches in diameter, is sunk to the clay bed, and inside 

this pipe a 1-!-inch pipe, having a drill attached to its lower end, is 

inserted. A stream of water is forced down the pipe, loosens the 

clay, and forces it up between the smaller and larger pipes. By 

adjusting the pressure of the descending water column the coarser, 

impure materials in the clay bed are left in the bottom of the well, 

and only the finer _material comes to the top. A very sharp finegrained white sand is separated from the kaolin as a by-product in 

the washing and is used for masonry. All the clay within a radius 

of 40 feet of the hole and through the entire thickness of the bed is 

pumped to the surface in this way, and the pipes may then be pulled 

and used in another hole. The kaolin forms about 5 per cent of the 

solution forced to the surface, the fluid having the appearance of 

milk. 

CORE DRILLING. 

GENERAL FEATURES. 

Core drills are little used for sinking wells, though they have been 

tried from time to time in developing new oil fields, and diamond 

drills have been employed to some extent in South Africa for deepwater wells. The core-drill principle is,- however, occasionally employed in connection with the more common well-drilling outfits. 

The advantage of core drills over all other types of boring machines is that they enable an accurate sample of the material penetrated to be obtained. They are therefore widely used in prospecting 

for coal and other economic deposits, for making borings for found!ltions for dams and similar structures, in preliminary tunnel investigations, and in excavation work. The importance of obtaining a 

true sample of the material penetrated is illustrated by the experience 

of a firm of contractors, who became bankrupt because at a certain 

depth they encountered hard conglomerate, instead of the gravel 

indicated by the drillings of a percussion outfit. 
U. S. GEOLOGICAL SURVEY WATER -SUPPLY PAPER 257 PLATE Ill 

A . HAND-POWER DIAMOND DRILL, WITH FRICTION FEED. B. STEAM-POWER DIAMOND DRILL, WITH HYDRAULIC FEED. 
CORE DRILLING. 79 

Rotary core drills of the several classes are alike in employing 

a hollow rotary drill that by abrasion wears an annular hole, leaving 

a core in the center. The drillings are removed continuously by 

water under pressure, and the core is broken off and removed from 

time to time. 

Core drills are intended primarily for drilling holes of relatively 

small diameter in hard material. They resemble hydraulic rotary 

outfits in method of operation, but the formation of a core and the 

necessity for its occasional removal makes the drilling process intermittent instead of continuous. 

Core drills may be used in all kinds of rock, from the hardest trap 

to the softest shale, but where a core is not especially desired drilling 

in the softer formations can usually be done more rapidly by means 

of percussion, hydraulic rotary, jetting, or some other method, and 

as a rule saving can also be effected in the cost of outfit. A percussion core drill is described on page 59. 

DIAMOND DRILL. 

OUTFIT. 

Diamonds were first used in drilling rock in 1863 by Rudolph 

Leschot, a French civil engineer. For deep-well drilling they were 

first employed by M. C. Bullock, who sank a hole to a depth of 750 

feet in Schuylkill County, Pa., to determine the existence and thickness o-f coal beds. · 

Diamond-drill machines (see Pl. III, A) to be worked by hand are 

made, but the large_r outfits (Pl. III, B) require a derrick, hoisting 

sheave, and hoisting drum similar to those employed in other methods of drilling. The drilling apparatus includes a force pump and 

water swivel, drill rods, and rotating device for turning them, feed 

mechanism, and a cutting bit. 

The derrick in most common use is a tripod from 20 to 80 feet 

high, the height varying with the work to be done. Where timber is 

easily available the derrick may be constructed of poles, but for 

drilling to depths of 1,000 feet or more a strongly braced 4-pole 

tower or a steel derrick is usually employed. The drill I'ods are 

smaller and lighter than those used with the hydraulic rotary outfit, 

and the hoisting drum, force pump, and water swivel, though similar, 

are correspondingly lighter and are of somewhat different design. 

Only one force pump is installed, as the danger of sticking if the 

water current is stopped is not so great as in the hydraulic rotary 

method. The drill rods are of heavy lap-welded iron tubing or of 

seamless steel tubing, with screw joints (fig. 151

- 2 ), and are 5 to 10 

feet long. The sectionf? ~!'~ ~dded a~ §inking progresses. · 
80 WELL-DRILLING METHODS. 

5 

2b 

2a 

II 

7 

FIGURE 15.-Parts of core-drilling outfit. 1, Davis calyx drill rod with coupling attached ; 

2a,b, end of a drill rod and rod coupling; 3, bit to be set with diamonds; 4, toothed 

cutter bit ; 5, chopping bit ; 6, safety clamp ; 7, toothed collar ; 8, coupling recovery 

taps. 
CORE DRILLING. 81 

In nearly all diamond-drill outfits the drill rods are rotated by 

means of bevel gears. In the smaller machines connection with the 

power is made also by "tight" gearing, either chain or cog drive; 

but in the larger machine belt drive is. used, so that the belt may slip 

if the drills become caught, as otherwise the rods may be twisted 

or broken. 

As the total weight of the rods in a deep bore may reach 15 or 20 

tons-a weight which would crush or break the diamonds-the rods 

must be supported and the drill must be fed into the rock slowly. 

Two feed devices-a differential feed and a hydraulic feed-are in 

general use, both designed to prevent the sudden and severe strain 

that would be brought upon the stones by drilling through soft and 

into hard rock with a positive feed-that is, a feed so regulated as to 

advance the drill rods equal distances in equal periods of time. 

In one style of differential feed used on many of the smaller diamond 

drills the drill rods are advanced by means of a frictional gear on 

the bottom of the feed shaft, which, by maintaining a uniform pressure on the drill, makes it sensitive to the character of the rock 

through which it is passing. A differential feed used on one style 

of calyx core drill advances the rods by a loop of rope which passes 

over a pressure yoke and is wound on two small drums. 

In the hydraulic feed the forward motion is accomplished and 

regulated by means of hydraulic pressure which is applied through 

a cylinder and piston. The cylinder is connected to the pump which 

supplies water for drilling, and a pressure gauge indicates the amount 

of pressure on the bit. This device is under the immediate control of 

the operator, who regulates the feed by a small lever. The cylinder 

is so constructed that the water can not escape from its bottom faster 

tha;n it enters at its top, and its lower part therefore always contains 

water. If a cavity is struck the drill rods hang on the piston, which 

is supported by the water, and as this is incompressible it prevents 

the rods from dropping into the cavity and the feed continues downward as regularly as if the drill were working in hard rock. Before 

the hydraulic feed was devised the diamond drill did not work satisfactorily in creviced rock because the drill and rods were apt to 

drop into cavities and thus break the diamonds. 

The bit is made of a ring or sleeve of tough but ductile steel, threeeighths to five-eighths inch thick, whose upper end is threaded to 

screw into the drill rods and whose lower end is turned true and 

bored with eight holes to contain the diamonds. The diamonds are 

carefully set in the holes so that their lowest points lie in a plane, and 

are arranged alternately on the inner and outer faces of the bit, so 

that the outer edges of four project a little beyond the outer face and 

give it clearance, while the edges of the inner £our project slightly 

beyond the inner face and clear the drill of the core. The diamonds 

65275°-W s P 257-11--6 
82 WELL-DRILLING METHODS. 

are calked in place by carefully swaging the steel firmly against them 

with light blows. The old method of setting was to drill into the bit 

a hole about the size of the diamond, insert the diamond, fill around 

it with copper or other malleable metal, and swage the stone in firmly; 

but this method was troublesome and the diamond was often broken. 

In the latest styles of diamond drill bit the diamonds are set in steel 

nibs which are soldered or brazed into their places in the bits. When 

these nibs are used the expert diamond setter's services may be dispensed with. 

Care must be taken that the bottom tips of the stones lie in a common horizontal plane and their outermost tips in the circumference 

of a circle; otherwise drilling will be done only by those diamonds 

that project downward or outward the farthest. This might result 

in drilling a hole of irregular shape and considerable inclination, or 

it might result in failure to drill at all. Grooves are cut across t;he 

face of the bit between the diamonds, and also on its outer side to 

permit the passage of drill water. A bit ready to be set with diamonds is shown in figure 153 • 

The shape of the bit and arrangement of the diamonds permit the 

stones to cut a path for the drill and slightly enlarge the cavity around 

it, and this clearance allows the drill to be easily lowered into the 

hole and also gives passage between the rods and wall of the hole for 

the drill water to convey the drillings to the surface. The stream 

of water also keeps the bit cool and prevents injury to the diamonds 

by heating. 

Two kinds of diamonds, known as carbons and borts, are used in 

diamond-drill work. Carbons are :found as opaque, irregularly 

shaped nodules, black on the outside and shades of gray on broken 

surfaces. They have no cleavage planes, and it is this quality, together with their hardness, which especially fits them for drilling in 

hard rock. Borts are semitransparent diamonds similar in appearance to the rough brilliant but differing in crystallization. They are 

usually nearly spherical i~ shape, are as hard as carbons but not as 

tough, and have a cleavage plane, so that when used in ~ard rock 

they may break; whereas carbons wear away but seldom break. Carbon's come mainly from Brazil; borts from both Brazil and South 

Africa. Borts are much cheaper than carbons and may be used in 

boring in soft rock. In some holes a toothed cutter bit (fig. 154 ) 

similar to that of the hydraulic rotary outfit is used in penetrating · 

soft rock. In moderately hard material a drill armed half with carbons and half with bort may be used, but for drilling in very hard 

rock only carbons are suitable. 

The diamonds :for a bit must be selected with special attention to 

uniformity of size and weight, as irregularity in this respect will 
CORE DRILLING. 83 

disturb the balance of stones and necessitate frequent resetting. 

They usually require resetting after eight to twelve hours' work, so 

that two bits are needed, or, if running continuously, three are often 

employed, so that drilling need not be suspended while the stones 

are being set. The size of diamonds used for drilling ranges from 

about 1 to 4 carats, according to the size of the bit. Stones of approximately cubical shape are best, as they are -

stronger and furnish better cutting faces. 

In the early drills the core was removed by 

means of gravel dropped down the rods. This 

became tightly wedged between the core and 

rotating barrel and caused the former to be 

broken off and held tightly so that it could be 

brought to the surface. IIi present forms of 

the drill a core lifter is placed in the barrel 

a short distance above the bit. Commonly this 

device consists essentially of a core barrel or 

shell and a split ring or sleeve. (See fig. 16.) 

The shell is bored with a slight taper downward, and within it the split ring is placed. 

This ring is usually wedge-shaped and often 

has inward projecting lugs to grip the core. 

Because of its tapering shape the ring is loose 

when in the upper part of the shell, but when 

it is pressed toward the bottom of the shell 

it becomes wedged under heavy compression 

and grips the core tightly. While the bit is 

in motion the ring does not rotate, but rides 

lightly on the core, sliding down over it as 

the bit advances into the rock. When the 

" run " has been made and the tools are hoisted, 

the raising of the . shell compresses the ring 

and causes it to grip the core, thus breaking 

it off close to the bottom and bringing it to 

the surface. In a core barrel of this type the 

wash water is forced downward between the 

b 1 d 1 · f FIGURE 16.-Plain core core and the arre , an w 1en penetrating so t barreL 

materials, as coal beds, the water may disintegrate the core and render the sample imperfect. The barrel 

also vibrates more or less and may cause the split ring to rub on 

the core so as to abrade it to some extent. In prospecting coal 

beds it is therefore customary to use a double core barrel which 

contains a tube that slides down over the core as fast as cutting 

proceeds and protects it from wear. 
84 WELL-DRILLING METHODS. 

DRILLING OPERATIONS. 

In starting a hole with a diamond drill the first requirement is to 

get down to rock. If the soil is thin, a pit is dug through it, a drive 

pipe is inserted, and a tight-fitting joint is made by chiseling out a 

seat in the rock, driving the pipe down and calking it firmly. If the 

soil covering is more than 10 or 12 feet deep, it is cheaper to drive 

the pipe to rock than to dig a pit for it. In places where the drivepipe can not be set into the rock with sufficient firmness to keep out 

the surface water a hole is drilled inside the drivepipe with a chopping bit (fig. 155 ) attached to the drill rods and a string of casing is 

put down to a depth sufficient to exclude the water. 

When ready to begin drilling the drill spindle is set to the angle 

desired for the hole, a bit and core barrel are screwed to the lower 

end of a joint of drill rods, and other rods are ad~ed so as to bring 

the bit to the rock. The upper length of rod is then clamped in the 

spindle, so that the bit is a little above the rock, and the water swivel 

is screwed to the top of the rods and connected with the pump. The 

pump is then started, and when the return water begins to flow from 

the top of the casing the drill is started and the bit is slowly run 

down to rock. If the rock surface is not smooth, the hit will at first 

drill only one side, but soon all of the diamonds are cutting the rock, 

or, as the driller puts it, the drill has an " even bearing." 

1Vhen the drill has been run into the rock the length of the core 

barrel drilling is stopped, but the pump is kept running long enough 

to wash all cuttings to the surface. A hoisting plug is then substituted for the water swivel and the line of rods is hoisted until the 

first drill-rod coupling is just above the safety clamp. (See fig. 156.) 

This clamp allows the rods to be hoisted, but grips them and guards 

against their loss by slipping downward and dropping into the 

hole. The top joint of rod is then unscrewed and passed out through 

the hollow spindle, the hoisting plug is lowered and screwed into 

the second length of the drill rods, and the line of rod:;; is hoisted 

another length. Each joint in turn is removed un:til the core barrel 

reaches the surface, and the core is then taken out. By reversing the 

process the rods are again lowered into the hole, the water swivel is 

connected, and drilling is begun on the next" run." 

CALYX DRILL. 

DEVELOPMENT. 

In 1873, shortly after Leschot first used diamonds for boring, large 

black diamonds of good quality could be purchased for $8 to $12 a 

carat; but since the introduction of the diamond drill they have 

advanced greatly in cost, and in 1910 were valued at $85 a carat for 
CORE DRILLING. 85 

a two-carat stQne or $50 for a one-carat stone. Borts are much 

cheaper; the rate·in 1910 was about $18 a carat. As carbons weighing 1 to 4 carats apiece are used in diamond drilling, the price of a 

bit set up ready for drilling is a large part of the initial cost. For 

prospect work this cost has been somewhat reduced by decreasing the 

size of the bore hole, but for water wells the 

diameter can not be reduced to less than about 

2 inches, and even this reduction in the size of 

the bit causes the drill rods to turn on so sharp 

a curve as notably to increase the d~fficulty of 

drilling and the probability of accident. 

On account of the increase in the cost of 

diamonds detern1ined efforts have been made 

by engineers throughout the world to discover 

some method of coring rock without diamonds. 

Various hard substances, such as corundum, 

chrome iron, chopped steel, and garnet, and 

many varieties and forms of material have been 

tried unsuccessfully, attempt even being made 

to grind the rock by means of a free abrasive, 

such as steel filings, fed down the bore hole. 

Bits were also made of the hardest metals, and 

it was due to experiment along this line that the 

calyx drill was invented in Australia. It is 

now in use in many parts of the world. 

DESCRIPTION. 

The hoisting and driving machinery of the 

calyx drill is similar to that of the diamond 

drill, and feed water is supplied through a 

swivel and hollow drill rods. The bit of the 

calyx drill is made of hardened tool steel and 

consists of a toothed collar, somewhat like the 

cutting shoe of the hydraulic rotary outfit, but 

having longer barrel and teeth (see fig. 157 ), 

the teeth being so set as to provide clearance to 

the core and to the bit and rods. 

Above the core barrel a cylindrical chamber 

FIGURE 17.-Calyx core 

barrel. 

or calyx, open at the top, encircles the drill rods (fig. 17). Into it 

the coarser rock fragments torn off by the drill bit are caught as 

they are dropped by the upward water current when its velocity 

decreases. They are removed when the rods are hoisted to remove 

the core, and furnish a second record, in inverted order, of the 

materials penetrated. This record is of especial value in material 

too soft to yield a good core. 
86 WELL-DRILLING METHODS. 

The action of the toothed bit in cutting the rock seems to depend 

largely on the torsional power of the drill rods, for the drill bites into 

the rock and resists turning until the twist of the rods forces it loose 

and partly around to a new grip. It thus has a "chatter" motion, 

which chips off fragments of the rock. Its action has been compared 

to that of the stone mason's chisel, which chips off rock fragments 

at each blow of the hammer. 

The calyx drill is not· restricted in size by such considerations of 

cost as is the diamond drill, and machines are built capable of taking 

cores 15 inches in diameter. 

CHILLED SHOT METHOD. 

Experiments in drilling by the use of loose abrasives poured down 

the drill hole led to the adoption for this purpose of chilled steel shot, 

such as is used in sawing marble and other stone. Other parts of 

the shot outfit are similar to those of the diamond drill, but cutting 

is-accomplished by revolving an iron or steel tube on the shot. A slot 

a few inches long and half an inch wide cut into the lower end of the 

tube or bit allows the shot to reach the cutting surface more readily 

and be more evenly distributed. Distribution is also aided by slightly 

beveling the edges of the tube so that the shot may get under it. 

Under the weight of the drill rods the shot bites into the rock and 

chips out or wears off small pieces of it, which are brought to the 

surface by the water current. 

That the supposedly round and smooth shot can thus wear away 

rock may seem at first almost impossible, but close examination of the 

tiny steel balls shows that they are slightly irregular in shape, and 

because of this unevenness of form they sink into the softer bit 

tube and are held firmly by it, abrading the rock surface as sandpaper abrades wood. The shot has no tendency to polish the _hard 

rock-a tendency sometimes shown by the diamonds used in the 

diamond drill. 

ACCIDENTS AND DIFFICULTIES IN CORE DRILLING. 

The most frequent accident in rotary core drilling is the loss of rods 

through leakage. To recover them a screw tap may be employed, 

being lowered into the top of the rods, where it cuts its own thread, 

and thus obtains a firm grip. Taps (see fig. 158 ) are made in various 

sizes and are used to recover casing, pipe, and core barrels, as well 

as drill rods. If the rod of pipe is bent so that a tap can not he used 

at first, the upper portion may be cut away with a reamer until the 

tap can be inserted. The position and condition of broken parts 
CORE DRILLING. 87 

may be ascertained, as in other drilling methods, by examining the 

lower end of the recovered portion, by using a mirror or by employing soap to obtain an impression of the upper part ·of the tools. 

In using the diamond drill in formations containing hard pebbles 

or nodules loosely embedded in softer material the diamonds may be 

torn out and their recovery may be difficult. One device used to 

recover them is a ball of beeswax attached to the end of the rods. 

Creviced rock offers difficulties to all core drills because of the uneven bearing it affords to the bit, and hence its tendency to deflect 

the hole. Crevices also cause loss o:f feed water and also of shot, 

when it is employed. These losses may perhaps be stopped by pouring into the hole oats, bran, sawdust, or other material that will swell 

under the action of water and fill the crevices. Care must be taken, 

however, that this material does not pack around the bit and prevent 

its withdrawal. 

COMPARISON OF CORE-DRILLING METHODS. 

The diamond drill is especially adapted to penetrate hard rock to 

great depths, and will bore a hole at any angle; hence it is especially 

useful in mineral-prospect work. It is somewhat restricted by the 

rock formation, however;. for example, no diamond-drilling firm will 

send a drill into the lead and zinc districts near Joplin, Mo., for the 

limestone there contains many chert nodules, loosely embedded, which 

tear out the diamonds. In highly inclined and flinty rocks there is 

also danger of loss of the stones. The high cost of diamonds limits 

the use of this drill to boring holes of small diameter, and hence to the 

higher classes of work, such as prospecting for ore deposits. 

The calyx drill is commonly used to bore much larger holes than 

the diamond drill, and in soft or moderately hard material it is 

cheaper. In very hard rock it works more slowly, however, and it is 

not adapted to boring holes at an angle greater than about 45° from 

the vertical. It is largely employed in coal prospecting and in 

boring holes for testing foundations. 

The shot method may also be used in obtaining cores of large 

diameter. In very hard material it is more efficient than the calyx 

cutter, but it is not adapted to soft material. It may be used for 

boring holes at any angle, provided the drill is rotated rapidly and the 

shot kept properly distributed by centrifugal force. 

All rotary core drills are portable and, as they can be taken apart 

for transportation on pack animals, can be used in regions where· 

more cumbersome outfits are debarred. Nearly any power can be 

used-electricity, compressed air, steam, gasoline, horse, or handbut where its use is possible steam is usually the best. 
88 WELL-DRILLING. METHODS. 

The three methods of rotary coring are sometimes used in boring 

the same hole, the style of cutting bit employed depending on the 

character of the ·material that is being penetrated. The shot and 

calyx bits are frequently interchanged, and on one of the leading 

makes of core drill the outfit is expressly designed to use a toothed 

cutter bit in soft and moderately hard rock and shot in penetrating 

the hardest materials. For this purpose a double water swivel is 

used, through one neck of which the shot is fed into the rods. 

The percussion core drill (see p. 59) should prove valuable in 

sampling coal beds and in other work in comparatively soft formations in localities where a cable rig can be advantageously set up. 

MINOR METHODS OF WELL SINKING. 

BORING. 

In alluvial deposits along streams and in other unconsolidated deposits of gravel, sand, and clay wells 2 or 3 inches in diameter are in 

some parts of the country bored to the ground-water level with a hand 

auger made by welding a carpenter's auger to a rod or pipe. The 

auger works more efficiently if the centering point is cut off and the 

lips are shaped as shown in Plate IV, 3. A wrench formed of a 

plumber's tee and two short pieces of pipe may be used to screw the 

auger into the earth and pull it out with its load of material, and 

the rod may be lengthened by adding other sections of pipe as sinking 

progresses. - (Pl. IV, 1.) 

Another much-used type of auger is formed by making a spiral 

coil of tire iron, shaping a cutting bit on its lower end, and welding 

or riveting the auger thus formed to a joint of rod .or pipe. (Pl. 

IV, 2.) Where the depth to water is not more than 25 feet these 

small augers may be fastened to a section of pipe long enough to reach 

to water. As the auger is heavy when loaded with material, a windlass or a small derrick with pulley blocks may be used in lifting it, and 

a platform may also, be built from which the auger can be steadied and 

turned. In boring through dry sand or other loose deposits a little 

water should be poured into the hole to cause the material to cling 

to the auger. 

Small wells bored with augers are adapted mainly to localities 

where the water level stands above the suction limit, for the hole 

usually bored is not large enough to admit a pump cylinder. The 

best suction pumps will raise water to the surface from a depth of 

about 28 feet. 

To complete these shallow wells, a pipe li or 2 inches in diameter, 

with a suction or pitcher pump (fig. 18 5 ) screwed to its upper end, 

is inserted to a point a short distance below the water level. In 
U. S. GEOLOGICAL. SURVEY WATER-SUPPLY PAPER 267 PLATE IV 

4 2 

3 

1. SMALL EARTH AUGER; 2, 3. EARTH-AUGER BITS; 4. DRIVE POINT AND SCREEN. 
MINOR METHODS. 89 

relatively coarse material a natural strainer is soon formed about the 

lower end of the pipe by pumping out the finer sand, and it is usual 

1 

2 

3 - 5 

FIGURE 18.-Well-boring tools. 1, Ordinary well-boring outfit; 2, 3, well-boring augurs; 

4·, special auger for penetrating bowlders or rock; 5, suction pump. 

to drill a number of small holes along the lower part of the pipe to 

aid in admitting the water. In finer material a screen is used to prevent the well from becoming clogged. 
90 WELL-DRILLING METHODS. 

For boring wells of larger diameter augers of other forms are used, 

and correspondingly heavier apparatus is employed for turning and 

raising them. Different shapes of auger are employed for penetrating different materials. Two common shapes are illustrated in figure 

182

- 3• The larger augers range in diameter from 3 to 36 inches. 

Casing is not usually required until the auger reaches saturated 

sands. Its use is then necessary to prevent caving and it may be 

driven down by a wooden maul or ram. Mud and water-saturated 

sand may be bailed out with a sand bucket, which in the smaller machines is handled with wooden rods instead of a cable,. as the rods 

enable it to be more easily pushed down into the soft material at the 

bottom of the hole. Hard layers of material may be penetrated by 

substituting for the auger a drill similar to that used with percussion 

outfits. It may be operated by hand, in connection with a drum and 

sheave, as in the self-cleaning method. · 

In regions where the formation is clayey and holds together well 

an auger o:f different shape has been devised and is employed for 

sinking wells several hundred feet in depth. It is used especially in 

the lower Mississippi Valley and is known as the Arkansas clay 

auger. The following description of this outfit is taken from a paper 

by A. C. Veatch: a 

The auger is 15 feet long. It consists of an auger barrel 4 feet long, which is 

made of cast steel, and resembles a 3-inch pipe sawed vertically in half. This is 

fastened by a flat piece of iron to a second auger barrel, H to 2 feet long; above 

this is a second piece of flat iron, square at the top and cut with threads for 

fastening to the wooden poles. At the bottom of the auger barrel, on the righthand side, is riveted a steel-cutting edge. * * * This is commonly called the 

cutting bit, and projeets inward H inches. On the opposite side and slightly 

above, is the "auger lip," which helps to hold the dirt in the auger barrel when 

the tools are lifted. In operation the auger is fastened to a short 10-foot pole 

known as the auger pole, and this to the regulation 26-foot pole. The tools are 

turned with a clamp, and when the bit begins to choke, the tools are lifted and 

dropped by means of a windlass. This operation jumps the dirt up in the bit, 

and so frees the lower end; it is termed "making a slip." If the clay is very dry 

a little water is added, and with the very sticky Cretaceous clay this process 

can be continued until the whole length of the auger is filled with a cylinder 

of mud. This 15 feet of mud represents about 10 feet in depth. Usually, however, the auger is filled for only about 10 feet, representing 7 feet of depth, 

before lifting the tools. • 

When rock is encountered, a bar drill is used. This is sometimes attached 

directly to the wooden poles and sometimes to iron poles. * * * 

When sandy layers are encountered, which will not hold in the auger, the sand 

pump is used or enough clay is dumped in the hole to make the sand stick 

together. 

In cases where wells of larger diameter are desired, or where it is necessary 

to enlarge the upper part of the hole for wooden casing, the 3 or 3! inch hole 

made with the Arkansas clay auger is enlarged with a reamer. 

a Veatch, A. C., Geology and underground water resources of northern Louisiana and 

southern Arkansas. Prof. Paper U. S. Geol. Survey No. 4e, 1906, pp. 95, 97. 
:M:lNOR METHODS. 91 

PUNCHING • 

. In a few localities where the material is very clayey wells are sunk 

by a punch instead of an auger. Of this method and its use in 

Arkansas and Louisiana Veatch says: a 

In regions where there are uniform clay beds without rocks or bowlders wells 

are often made with a well punch. This consists of a cylinder of steel or iron 

1 to 2 feet long, split along one side and slightly spread. The lower portion is 

very slightly expanded, sharpened, and tempered into a cutting edge. In use 

it is attached to a rope or wooden poles and lifted and dropped in the hole by 

means of a rope given a few turns around a windlass or drum. By this process 

the material is forced up into the bit, slightly springs it, and so is held. When 

the bit is filled it is raised to the surface and emptied. When working in very 

dry clay water is sometimes added to aid the bit in "picking up" the material. 

Thin sand layers are passed by throwing clay into the well and mixing it with 

the sand until the bit will take it up. 

This process is not very extensively used in this region, n.nd is not so 

practicable as the Arkansas clay auger. 

-DRIVING. 

Where the water level is within the suction limit of about 25 to 

30 feet below the surface and the water-bearing beds are unconsolidated, small water supplies may be cheaply obtained by wells sunk 

by driving into the ground a strainer and drive point fastened to 

a piece of pipe. Other lengths of pipe are added and driving is· 

continued until the strainer reaches a water-bearing layer. 

Unless the depth at which water can be obtained is previously 

known, the well is tested from time to time by a suction pump 

screwed .to the upper end of the piP.e. When desirable water is 

reached the well is pumped rapidly for some time to free the strainer 

from particles of sand and cl-ay. The coarser material adjacent to 

the strainer is thus washed free of sand and forms a natural filter at 

the bottom of the well. One style of drive point and screen is shown 

in Plate IV, 4. 

The pipe may be 1 inch to 3 inches in diameter, and is usually 

driven into the ground by a wooden or iron maul, which may be 

manipulated by hand. Often, however, a heavy weight is used, operated by a revolving drum and hoisting sheave, as in the self-cleaning 

method ( p. 64), or by horsepower devices of various styles. The 

greatest difficulty encountered in driving wells is in striking rocks. 

Unless the rocks yield to the blows of the maul or can be broken up 

by explosives, the well must be abandoned. 

Clay and sand often cling to the screen and render it worthless. 

To obviate this the pipe may be driven to the required depth with 

a Veatch, A. C., Geology and underground water resources of a portion of northern 

Lop.isiana and southern Arkansas: Prof. Paper U. S. Geol. Survey No. 46, 1906, p. 97. 
92 WELL-DRILLING METHODS. 

only u drive point and then pulled up a distance equal to the length 

of the screen. The drive point, which fits loosely on the pipe, remains behind and the screen is lowered upon it. This style of screen 

can also be removed and cleaned if it becomes clogged and ineffective, 

but it can be successfully used only when the depth to the waterbearing layer is known, since a test for water can not be made until 

the pipe is raised. 

A modification of this outfit consists of a screen attached to a drive 

point and so arranged that the drive pipe slips down over the screen 

and rests on the point while the two are being driven. In testing for 

water the pipe is withdrawn a foot or two, a pitcher pump is screwed 

to its upper end, and the well is tested by pumping. If water is not 

procured at the depth tested the pump is removed and the pipe is 

driven down again to the drive point and deeper into the ground. 

The only drawback to this method is that pebbles may lodge against 

ihe screen when the pipe is withdrawn, and when it is driven down 

again they may tear the screen and impair its usefulness. 

If the water that is tapped contains a large amount of iron a thick 

crust may form on the pipe and screen and reduce the inflow of water, 

or even shut it off entirely. The incrustation may be loosened and 

broken up into fine particles that may be pumped out with the water 

by pulling the pipe a few inches, by driving it down a short distance, 

or even by rapping the pipe sharply. 

The driven well is used to a large extent in the Atlantic and Gulf 

coastal plains, and is becoming common in the Mississippi Valley and 

the prairie plains. It is much used to obtain water supply for stock 

in farm pastures where the ground water is a short distance below the 

surface. It has also been used with great success in army camps in 

many parts of the world. British army officials call it the Abyssinian 

well, as it was first used extensively for army water supply during the 

~1\.hyssinian campaign of 1895. 

The driven well has the disadvantage of using surface seepage 

water which is likely to be contaminated. The site of the well should 

therefore be carefully selected and the safety of the water be determined from the character of the material penetrated, the direction of 

surface drainage, and the depth of the well. 

SPECIAL OPERATIONS IN DRILLING WELLS. 

The sinking and finishing of wells involves a number of special 

operations and is attended by many difficulties. The following discussion pertains especially to wells put down with standard outfits 

(see pp. 34-55), although most of it is also applicable to wells drilled 

by other methods. 
SPECIAL OPERATIONS. 93 

PACKING. 

N ecessity.-In constructing a well to obtain flowing water it is 

essential under some conditions that a water-tight joint be made 

between the casing and the rock; otherwise water that enters the well 

below the joint will find an outlet, and on rising outside the casing 

will enter porous sands at a higher elevation and fail to reach the 

surface. Furthermore, if porous rock is penetrated below the point to 

which the well is cased, it may be necessary in order to conduct the 

flow to the top to insert a line of tubing to a point below all such 

material. 

In oil wells a small amount of water may enter at the point where 

the casing joins the rock without doing serious damage if the head 

of the oil is strong and forces all invading water to the Sl!H'face, for 

the water may be easily separated from the oil in the receiving tank 

·· by gravity. A gas well, on the other hand, should be dry,-unless the 

:2- gas pressure is so great that all water is held back by it. More-

~ over, gas always escapes under natural pressure, while oil is not uncommonly pumped, so that in oil wells the water is brought to the 

surface and does not accumulate as it would in gas wells. 

It was thought essential at one time that water should be cased off 

during drilling operations, but the presence of water in some of the 

Pennsylvania oil fields, notably at Macksburg, led the drillers to experiment successfully with "wet" hole drilling, which saves the cost 

of the additional casing otherwise necessary. Casing is not now so 

extensively used until the well approaches the oil sands. 

Near Chicago a bed of soft shale occurs at a depth of about 1,000 

feet. This material is prevented from caving and clogging a well by 

placing a packer below it and allowing a piece of pipe to extend upward from the top of the packer to a point above the upper surface of 

the shale. Where water under pressure is encountered in the shale 

it is necessary to extend the pipe until it reaches beyond the height 

to which the water will rise. Drilling is then continued through the 

, pipe and packer. 

In the l{ittanning fields in Pennsylvania several gas sands are encountered. The pressure in the upper sands has been reduced by years 

of flow from the wells until it is much less than in the lower gasbearing layers. If the gas is allowed to come into the well under its 

own pressure, it forces its way upward until it reaches the upper 

sands into which it leaks. This process sometimes results in one 

well supplying gas to an adjacent one. The discovery of the rejuvenation of gas wells in upper gas-bearing sands by sinking new wells 

to lower sands in which gas was under greater pressure led to recognition of the necessity for separating the several productive layers. 

For this purpose a gas packer, similar to the one shown in figure 913 
94 WELL-DRILLING METHODS. 

(p. 53), is lowered into the well to a point above the lower and more 

productive gas sands, with casing extending from the packer to the 

surface. This arrangement separates the gas o£ the upper and lower 

beds so that both sources can be drawn upon. In this way the entire 

flow o£ gas from the deeper sands is confined to the well that taps 

them. 

Packing methods.-In oil wells the water in the rock between the 

surface and the capping stratum overlying the oil sands is shut out 

by first drilling 10 or 12 feet into the compact shale that ordinarily 

forms the overlying stratum. After the hole has been cleaned out 

a few bucketfuls of moist drillings are thrown into it and the string 

of casing is then inserted and set in these drillings in the bottom of 

the hole. The driller then redrills the loose drillings with a smaller 

bit. That portion of the cuttings which is between the casing and the 

wall o£ the well settles down very compactly and becomes as effective 

as clay in preventing water o£ higher water-bearing strata from entering the drill hole. The effectiveness o£ this operation is increased 

by a process called "reaming out the hole," which in this connection 

signifies the substitution o£ a smaller bit than the one previously 

used and drilling with a shorter stroke. In this way the wall of the 

well is made smoother than it would otherwise be, and the hole is 

tapered to a size a little less than that of the drive pipe. Into this 

funnel-shaped hole the pipe is gently driven, making a snug joint. 

Testing joints.-The joint may be tested in two ways. In one 

method the casing is filled with water and allowed to stand. I£ the 

water does not sink away the joint is known to be tight. The other 

method consists of lowering into the well below the joint a casing 

tester-a funnel-shaped instrument with an anchor attached that enables it to be set at any point in the well. It fits the well snugly and 

prevents water from passing it on the outside. After it has remained 

in the well for a few hours or days it is withdrawn and examined. 

I£ it contains no water it is evident that no leakage occurs, and drilling will then be continued. 

I£ a joint continues to leak after the casing has been reset, the pipe 

may be withdrawn, closed at one end, connected with the boiler, and 

tested by steam. If no defects are found it is put back and set into 

the rock at a greater depth. If the rock at the bottom of the casing 

is broken and full o£ crevices, a tight joint can not be made at that 

point. This condition occurs infrequently, but when it does happen, 

i£ it is imperative that the joint be made water-tight, an enlarging 

drill or reamer (fig. 66 , p. 40) is used to make the hole large enough to 

let the pipe down to a point where a tight joint can be made in the 

solid rock. This obviates redrawing the entire string of pipe. · 

Flamseed.-In the early days of oil exploration in this country a 

bag o£ flaxseed was sometimes inserted at the point where the casing 
SPECIAL OPERATIONS. 95 

was to be set, the casing was let down, and that part of the bag which 

occupied the center hole was drilled out, leaving a considerable 

amount of seed between the casing and the well wall. This seed 

quickly swelled and closed the place in which it lay, thus preventing 

the entrance of water. Bags of beans and peas have also been used 

in a similar manner. For use a short distance above the end of the 

pipe the bag of flaxseed may be fastened around the casing, so as to 

swell and fill the space between the casing and wall of the well. 

Cement.-Another method consists in filling up 5 or 6 feet of the 

bottom of the hole with cement, into which the casing is set. The 

cement hardens and excludes the water, and the portion within the 

casing is then drilled out. This method has been much used in the 

Baku oil fields of Russia, but its proper application is said to re-

·quire great skill, as the settling qualities of cement are destroyed or 

seriously impaired by contact with oil or by the presence of lar'ge 

quantities of salt or other minerals in the water. Furthermore, the 

cement is expensive, and it deteriorates very rapidly if stored. Another unavoidable difficulty in its use inheres in the fact that there 

is usually water in the drill hole at the time that means are taken for 

its exclusion, thus making it necessary to convey the cement to the . 

well bottom in tubes, and not allow it to filter through a long column 

of water. Flush-jointed, high-pressure tubes with extra long screw 

sockets are required for this work. 

The process of cementing is carried on in Russia in a. way very 

different from that followed in this country. The casing used is of 

unusually large size, ranging np to 36 inches in diameter. After 

being set it is entirely filled on the inside with a mixture of clay and 

sand, and cement is then carefully poured into the space between the 

casing and the rock. The cement excludes all water from this space 

and prevents its entrance into the well through imperfect joints or rivet 

holes, for the casing of Russian wells is not like that used in this 

country, but is thin, and the joints are riveted instead of being 

screwed together. After cementing has been completed the clay and 

sand on the inside of the casing are removed in the same manner as 

the original rock which occupied that space, but of course in a much 

shorter time, as the material has not had time to become compact. 

Asphalt.-Asphalt has also been used for packing, being melted 

and poured down the outside of the casing so that when cool it forms 

a S(jlid mass that water can not penetrate. The method is expensive, 

as the water in the well has to be heated with steam before the asphalt 

is poured in; otherwise the meeting of the two fluids congeals the 

asphalt and prevents it from flowing down where wanted. Trouble 

has also resulted from the refusal of the asphalt to set, even after 

considerable time, for, being viscous, it exerts a great external pressure on the casing and threatens to crush the latter if much is used. 
96 WELL-DRILLING METHODS. 

This method of shutting out water has therefore not attained Importance. 

Rubber.-In many wells it is much more economical and effective. 

to case off the water by rubber packers, which are made in styles to 

suit various conditions. The device in most common use (see fig. 913 ) 

consists essentially of two metal cylinders united by a third hollow 

cylinder of rubber, usually an inch or two thick and varying in 

length and diameter with the special conditions to be met. This 

packer is lowered into the well by lengths of pipe to the position 

which it is to occupy. A weight is then dropped into it, which releases the wedges and spring, A (see fig. 913 ); the spring throws 

the wedges up the taper of the cone, B, and when the packer is lowered under the weight of the drilling tools or casing the wedges catch 

the wall of the well. The rubber cylinder, C, expands outward and 

snugly fits all the irregularities of the well wall, thus preventing the 

passage of water. When once placed, this packer can be raised, but 

it can not be lowered again without being brought to the surface and 

reset. 

In some wells where a small amount of oil or gas is struck in upper 

strata the attempt to obtain a greater production by drilling the hole 

deeper results in finding water instead of oil or gas. To shut off the 

water a packer consisting of a rubber plug with a tapering hole is 

used. A tapering mandrel, either of wood or iron, is driven into the 

plug and expands the rubber to fit the wall of the well so as to 

effectually shut off the water below. 

Rubber packers are also employed in drilling wells where gas is 

encountered above oil-bearing strata. Instead of casing off the gas 

or allowing it to waste in the air a gas packer is introduced, which 

confines the gas between the casings and forees it to the surface. 

After a packer has remained in a well for some time and has 

becomes embedded by the accumulation of sediment from the well 

wall it may be jarred loose and then removed by connecting it to a 

packer jar. 

Concerning the durability of rubber packers it is difficult to make 

definite statements. It is, however, safe to say that the rubbers do 

not become uselesS from decay in a few years. The material used for 

packers contains probably not more than 60 per cent of pure gum. 

The greatest difficulty found in a packer made of high-grade rubber, 

and to a greater or less extent in any packer containing rubber, is its 

tendency to swell. This swelling does not affect the efficiency, but 

makes it very difficult to remove the packer if the casing is pulled for 

repairs or for cleaning. Packers are usually destroyed, not by rotting or by any chemical action while in the well, but by being torn 

during removal. 
SPECIAL OPERATIONS. 97 

CLEANING. 

In water-bearing or oil-bearing sand or rock that is firm and hard 

and will stand up in the well wall, a well may be completed simply 

by cleaning out the pores of the productive layers by strong pumping, 

which draws into the well the finer drillings that may have collected 

on the side of the hole and increases the delivery of water or oil. 

vVhile cleaning is being done the pumps should not be stopped until 

sand is no longer discharged with the liquid, otherwise the sand will 

settle about the valves of the pump and make it impossible to start 

pumping again without drawing the pump rods and valves, cleaning 

them out, and resetting them. 

An interesting operation in the care of oil and gas wells is the 

cleaning of the hole after the well has been producing for some time. 

Many of the first wells drilled in an oil or gas region penetrated. only 

the first few feet of productive sand, the pressure being so strong at 

that depth that it lifted the tools from the well, or at least prevented 

further drilling. In time, however, such wells become clogged with 

sediment, the pressure decreases owing to the removal of gas and oil, 

and the wells must be cleaned to become profitable producers. 

Where the sands carry gas or oil under light pressure, the hole is 

drilled through them and three or four feet into the underlying 

formation. A chamber is thus formed in which sediment may collect, 

leaving the whole surface of the sands available for the discharge of 

gas or oil. Some wells accumulate three or four feet of sediment in 

as many years. This settles and becomes as hard as the original rock. 

In order to clean a well a derrick may be erected over it, as when it 

was first drilled. The other parts of the outfit used in drilling are 

then set up, the accumulated sediment is drilled loose and bucketed 

out, and the hole is deepened so that the advantage of the increasing 

pressure with depth may be obtained, or a rese~voir supplied in 

which the collecting sediments may be caught. The derrick that one 

sees erected over oil wells in some oil districts is not usually the derrick used in drilling the well, but the one erected afterwards to clean 

the well or draw the pump rods, though in many districts the derrick 

used in drilling is retained. In cleaning out old wells whose rig tim~ 

hers and wheels have rotted, resort is sometimes had to a mounted rig, 

which can be quickly run into position under the derrick. 

At each cleaning a charge of 80 to 100 pounds of nitroglycerin is 

exploded in the bottom of the well to increase the yield. In many 

oil fields this is done regularly. Cleaning may become necessary 

again because of the caving in of the oil sand as the result of torpedoing, for in torpedoing the well even very hard rock is broken up 

and may cave into the hole. The cleaning of a well in this way often 

results in increasing the flow by 10 to 15 barrels a day. The operation 

65275°-W s P 257-11--7 
98 WELL-DRILLING METHODS. 

as above described costs about $400. Some wells are cleaned every 

three or £our years; other wells drilled twenty years ago have not 

been cleaned since they were put down. 

The pores o£ an oil well may also be cleaned by a process called 

" flooding." This is to be distinguished £rom the term " flooding " as 

applied to the natural entrance o£ water into the oil and gus sands. 

In order to clean a well by this process, a large quantity of crude oil 

is poured intD the well down one side o£ the casing. This runs down 

with great velocity, and as it passes over the well wall it cleans out the 

pores by friction and suction, and thus allows a greater production. 

The yield o£ wells treated in this way is never greatly increased, but 

the operation is very simple and inexpensive, and the increase is 

generally sufficient to make it profitable. 

SCREENING. 

If the well is sunk into unconsolidated materials, such as glacial 

material, coastal-plain deposits, river flood plains, and waste-filled 

valleys, a screen must be used· which will permit water or oil but not 

sand in serious amount to enter. 

In the northern part o£ the United States oil wells are not usually 

obtained in unconsolidated materials, but in California and in Texas 

they are not uncommonly sunk entirely in such deposits. In the Texas 

oil fields the screens or strainers are made o£ ordinary pipe, usually 

2 to 6 inches in diameter, ·perforated with holes about one-quarter 

inch in diameter and 2 inches apart. The pipe is then wrapped 

around with iron wire. I£ the sand is fine, the wire is wrapped close; 

i£ it is coarse, space is left between successive wrappings. This kind 

of strainer is supplied by machine shops throughout the oil fields, and 

can be made by any mechanic. 

A water-well screen similar to the one just described is in use in the 

Mississippi Valley £rom St. Louis to the Gulf, and is made by wrapping No. 14 wire, 10 to 14 wires to the inch, around'perforated wood 

or iron piping. The closeness of the wrappings, as in the case o£ the 

oil-well screens, depends on the fineness o£ the material to. be screened 

out. vVooden piping or tubing as a base £or the screen is often preferred for water wells on account of the rusting of iron pipe. In some 

wells these screens are 100 feet long. The weight of the wire screen 

and the impact of the sand pressing against it when set prevent the 

buoyancy of the wood from lifting the pipe. 

Patented strainers are also used, especially in water wells. Some 

makes, like the Layne strainer, shown in figure 19, a, differ £rom the 

shop-made ones in the shape of the wire used. In the Layne and 

similar streainers the wire presents a smooth surface to the sand, and 

thus reduces the clogging of the screen and insures greater production and a longer life to the well. 
SPECIAL OPERATIONS. 99 

The Cook well screen (fig. 19, b) is also in favor with water-well 

drillers and is used extensively throughout the United States. It 

consists of a single piece of seamless brass tubing, perforated by horizontal slits, which are made in different widths for different sizes of 

material, and are cut with a beveled edge on the inside of the screen 

a 

b FIGURE 19.-Well strainers: a, Layne strainer; b, Cook strainer. 

to give a minimum amount of friction in the slit with a maximum 

amount of water delivered, and a smooth outer surface that reduces 

the clogging of the apertures to a minimum. The screen may be set 

in the bottom of the well, the pipe drawn until it is almost flush with 

the top of the screen, and a lead seal inserted at the joint, or the screen 

and pipe may be united by a screw coupling. 
100 WELL-DRILLING METHODS. 

TORPEDOING. 

OIL WELLS. 

In an early record of the development of the Pennsylvania oil fields 

the following statements occur concerning the practice of torpedoing 

wells: a 

In 1862 Col. E. A. L. Roberts, then an officer in the volunteer service and 

with his regiment in the Army of the Potomac in front of Fredericksburg, conceived the ide~ of exploding torpedoes in oil wells for the purpose of increasing 

the production. He made drawings of his invention, and in November, 1864, 

made application for letters patent. In the fall of the same year he constructed 

six torpedoes, and on the 2d of January, 1865, he visited Titusville to make his 

first experiment. Colonel Roberts's theory was received with general disfavor, 

and no one desired to test its practicability at the risk, it was supposed, of 

damaging a well. On the 21st of January, however, Colonel Roberts persuaded 

Captain Mills to permit him to operate on the Ladies' Well, on Watson Flats, 

near Titusville. Two torpedoes were exploded in this well, when it commenced 

to flow oil and paraffin. Great excitement, of course, followed this experiment 

and brought the torpedo into general notice. The result was published in the 

papers of the oil region and five or six applications for patenting the same invention were immediately filed at Washington. Several suits for interference were 

commenced, which lasted over two years, and decisions in all cases were rendered declaring Colonel Roberts the original inventor. 

Nothwithstanding the success of the first experiment, operators were still very 

skeptical as to the practical advantages of torpedoes, and it was not until the 

fall of 1865 that they would permit the inventor to operate in their wells to any 

extent, from fear that the explosion would fill them with rock and destroy their 

productiveness. 

Despite the above assertions several other men had, as early as 1860, 

successfully exploded charges of powder in oil wells in the attempt to 

increase their production. 

llf ethods.-Many oil wells are now torpedoed as soon as possible 

after the oil sand is reached. For this purpose nitroglycerin in 

amounts ranging from 3 to 8 quarts is lowered into the well in tin. 

shells provided with suitable firing heads. The shells· are 3 to 5 

inches in diameter and the length depends on the size of the charge 

used. The shell is placed in the top of the casing, fastened there, 

and filled by pouring in the nitroglycerin from cans. A lowering 

line is then attached and the charge is slowly lowered to the bottom 

'of the well, when the hook at the top of the can disengages and the 

line is hauled up. For a large shot several shells are used, one resting on top of the other. I£ it is desired to shoot the well some distance from the bottom, an anchor is used. This is simply a small 

tube, which supports the shell at the proper depth. The nitroglycerin 

is then exploded by dropping into the well a small iron casing called 

a " go-devil," which strikes the can and explodes the charge. Another 

method of exploding is by means of the time fuse. The squib which 

a Henry, J. T., The early and late history of petroleum, 1873, pp. 251-252. 
SPECIAL OPERATIONS. 101 

carries the time fuse is made hollow in the center to hold about a pint 

of nitroglycerin, and into this nitroglycerin the end of a long fuse is 

inserted, on which is a large fulminate cap. The fuse is cut so as to 

burn a few minutes, according to the depth of the well. It is inclosed 

in a hollow covering, the interstices are filled with sand, and after 

lighting it, it is lowered on top of the charge. 

Torpedoing, of course, is practiced only in wells whose production 

is slight when they are first drilled or becomes so after they have 

yielded oil for some time. A well may be finished for the torpedo 

by an enlarging reamer, which gives a chambered hole, and results 

in the charge producing greater effect. It is especially adapted to 

soft rocks where the crevicing of the oil sands can not otherwise be 

readily accomplished at a sufficient distance from the charge. 

Effects.-In most wells the explosion takes place at so great a depth 

that there is little immediate surface effect, only a slight. jar of the 

ground and a dull report being perceptible. In a few seconds, however, the enormous force of the explosion is shown by the violent 

ejection of oil, stones, water, and fragments of the tin shells. 

The effects of shooting are not permanent, and after being shot 

many wells decrease permanently in yield. In some wells the flow 

may be again increased by lowering the tools and stirring the bottom-" agitating the well," as it is called. It is believed that when 

the tools are withdrawn a partial vacuum is suddenly created and 

the pores of the oil sand are cleaned by the heavier inflow of oil into 

the cavity formed by the explosion of nitroglycerin. 

A good flow does not always follow a shot. Sometimes the shattered fragments, instead of being thrown out, become wedged together 

and choke up the hole. In this event the drilling tools must be put 

in again and the material drilled out. This is a disagreeable job, 

as the well is full of foul oil and the poisonous burnt products of 

nitroglycerin, which are occasionally thrown out over the men and the 

machinery. 

When torpedoes are exploded in sands that are very friable large 

quantities of material fall into the hole and must be cleaned out. 

This is true of wells at Bartlesville, Okla., Casey, Ill., and Chanute, 

l{ans. Agitation is also necessary in the friable sands, as so much 

material is finely pulverized by the explosion and driven into the 

pores of the sand that they are practically closed and oil does not 

begin to flow until they are opened again. That this action takes 

place is known from the stronger flow before than immediately after 

shooting and the flow after agitation of a very liquid mud, which is 

followed by a rapid increase in the flow of oil. The good effects of 

an explosion would therefore not be realized in friable materials if 

agitation were. not practiced. 
102 WELL-DRILLING METHODS. 

The explosion of a torpedo has a damaging effect on the ~asing if 

this extends down near the point where the discharge takes place, 

for it is bent and torn irregularly and is thus rendered more difficult 

to pull, should it be desired to save it later. 

WATER WELLS. 

Explosives are used to some extent in water wells for the purpose 

of increasing the supply and providing a reservoir for the water, and 

there appears to be no reason why, under favorable conditions, their 

use should not be as beneficial as in oil wells. If water is drawn from 

rock fissuring the rock will certainly increase the area from which 

delivery is made to the pump. In a limestone region, where the 

underground water, like the surface water, runs in more or less definite channels instead of percolating slowly as a broad and thick 

sheet, the torpedoing of a well would almost surely increase the number of contributory veins. In such a region the success of a well 

depends so largely on chance, the diameter of the hole being small 

and the water veins few, that torpedoing would seem to be beneficial 

to all wells and to determine absolutely the success of some. The 

experiment should be more generally tried. 

FEATURES OF WELL CONSTRUCTION. 

DIFFICULTIES ENCOUNTERED IN SINKING WELLS. 

Accidents in well drilling are common and some of them may be 

unavoidable. Excessive strain on any part of the apparatus may 

cause it to break, and before drilling can proceed the broken parts 

must be removed and replaced. Many accidents are of trifling importance and cause little trouble or delay; others are very serious and 

may cause delays of weeks or months. 

All the accidents that may happen can not be described here; only 

the more important ones will be noted. The common accidents may 

be divided into two classes-(1) those caused by losing tools in the 

well and (2) those due to geologic conditions. The contractor usually holds the driller responsible for accidents of the first class, but 

not for those of the second class, unless the formation is well known 

from previous borings. 

LOSS OF TOOLS. 

CAUSES. 

Tools are usually lost as the result of one or more of the following 

conditions or causes: 

1. A worn cable. The stretching and bending of the part of the 

cable immediately above the socket cause it to become thin and 

frayed after a few weeks' wear. 
DIFFtCUt/.rtES IN S1NKING WELLS. 103 

2. The imperfect attachment of the cable to the socket. The joint 

should be tested by putting a strain on the rope while the drilling 

tools are anchored at the surface. 

3. Neglect in setting up the tools after each run. If the parts are 

not securely fastened together they become unscrewed and fall into 

the drill hole. 

4. Paying out too much or too. little cable. If too much cable is 

paid out, the jars will batter and break; if too little, the whole weight 

of the tools will fall on the cable and strain it excessively. 

5. Crystallization of the iron of the tools through successive jarrings, brought about by the magnetization of the iron. The effect 

of magnetization on the drilling tools is to decrease their tensile 

strength. The screw pin of the auger stem may break froni this cause. 

Probably no other engineering operation requires more deftness and 

ingenuity than " fishing " in a drill hole, owing to the great depth 

of many drill holes and the small space in which the driller must 

work. To ascertain the nature of an accident one-half mile below the 

surface, in a hole perhaps only 6 inches in diameter, by means of a 

cable having a very appreciable stretch, is clearly an operation requiring great skill. As the string of tools is usually more than 50 

feet long, weighs over a ton, nearly fills the hole, and is wedged in 

so tight that the strongest cable could not pull it loose in ~ straight 

pull, the conditions involved in some fishing jobs is obviously unusual. 

Occasionally the driller is compelled to break up the broken tool in 

the well, crushing it with the drill by repeated blows. 

LOCATING LOST TOOLS. 

The first step in recovering a lost tool is to learn the shape of its 

upper end and the position in which it lies in the well. This knowledge may be obtained by loweri,ng over the tool a sheet-iron vessel 

containing soap or other soft material, in which an impression is 

easily made. An examination of the mold then enables one to determine the position of the tool and to devise means for its recovery. 

If the fallen object has been caught in the well wall above the oil 

or w·ater or lies in a dry hole, its position may be determined by 

reflecting light into the well from a mirror. It was perhaps this 

operation which suggested the invention of a photographic device for 

determinations of this character. The device has not been used much 

in this country, although it seems that where a considerable anwunt. 

of money depends on the early completion of a well whose drilling 

has been delayed by loss of tools it could be used to great advantage. 

The device was invented by Mr. Loran, a Baku engineer, and both 

the instrument and process of photographing have been described by 

A. Beeby Thompson. 
104 WELL-DRILLING METHODS. 

Thedevice consists of a stereoscopic photographic apparatus, which 

is lowered to a point near the lost tool, light for the negative being 

furnished by an electric current carried by wires arranged in the 

camera. Concerning its construction Mr. Thompson says: a 

.An internally blackened, ben-mouthed vessel, at the small upper end of which 

is fixed the stereoscopic camera, and at the sides of which are fixed two small 

electric lamps with shades refleding the light downward, is attached to a sinker 

rod with guides. Incased in an air-tight chamber above the photographic device 

is an electric accnmnlntor, which snpplies the light, and interposed in the circuit is a small clock that can be regulated to produce contact at any desired 

time, switching on the light and opening the camera shutter at the same moment. 

Above this is placed a cylinder in which compressed air is stored, leading by 

minute tubes to the bell-mouthed photographic vessel beneath. By a clever 

device a quick upward or downward motion of a few inches causes a disk, nearly 

equal in size to the well, working freely on the central spindle, to rise or fall 

and transmit a motion to a lever which actuates an air valve leading from the 

air vessel. The pressure of air must exceed the pressure due to the submergence of the apparatus in the liquid, and on the air valve being opened the 

fluid is displaced in the bell-mouthed vessel and an undisturbed view ·of the lost 

article is secured. After an exposure of one or two hours the air is shut off 

by a repetition of the before-mentioned jerk and the apparatus raised. 

Some very good photographs made in this way are given in Mr. 

Thompson's book, showing the exact shape and position of fallen 

cable, wrenches, and other tools. 

It is strongly urged that drillers in this country try the invention 

where it is very desirable that the exact position of the tools be determined before fishing operations are begun. 

RECOVERING LOST TOOLS. 

Most of the instruments made for recovering lost tools are expensive, 

and so many of them have been devised that one contractor can not 

afford to own a complete set. Usually he purchases first the ones he 

is most likely to need and others as he may require them. 

Slip socket.-If the drill is lost in the well, but is not jammed tight, 

it may be possible to lower a spudding spear (fig. 201 ) into the well 

and prod the top of the drill loose from the wall. The drill n1ay then 

be grasped and removed by a slip socket (fig. 202 ), which consists 

of a pair of slips inserted in a tubelike instrument and suspended by u 

light string. The teeth of the slips are beveled upward, so that when 

the socket is lowered the slips readily move downward over the upper 

part of the lost tool. By quickly jerking the socket upward the 

string supporting the slips is broken, the teeth bite into the tool, and 

as the socket is raised the beveled groove in which the slips work narrows the space and causes the grip to become more firm. In this operation it is ·essential that jars be used to cause the teeth of the slips to 

bite as deep as possible into the drill, and also to jar the drill from the 

a Thompson, A. Beeby, The oil fields of Russia, 1904, 2d ed., 1fl08, p. 164. 
DIFFICUL'l'1ES IN SINKING WELLS. 105 

rock in which it is held. If it is impossible to lift the tool, the socket 

may be driven down again. The slips are thus raised and are automatically caught on the side of the socket. If a harder pull on the 

object is required the socket should be brought to the surface and 

reset. If the jars should be broken and the string of tools fall into 

the well the tools may be withdrawn by lowering a slip socket of 

special pattern over the sides of the broken jar. 

The slip socket was invented in this country and has been adapted 

to many uses and is more employed than any other instrument for lost 

tools. If it is properly arranged before being lowered into the well, 

it will not fail to seize the lost object and it grips it with greater and 

greater force as stronger pull is applied to the drill rope, and if the 

driller is unable to bring enough force to bear on the cable to withdraw the tools, it may easily be released and raised. 

If tools have fallen far, and have become firmly embedded in the 

rock at the bottom of the well the fishing jars must be very long and 

the longest possible stroke must be given to the walking beam. The 

tools may usually be loosened by repeated blows and then removed. 

Horn sockets.-If the tools have fallen only a short distance they may 

be removed by a horn socket (fig. 203 ), a tube with two slits, cut 

on opposite sides, which when jammed down over the fallen tools 

expands slightly and obtains a friction grip. It is cheap, easy to 

operate, and is almost as much used as the slip socket. 

Electro-magnet.-Another device used in fishing is a powerful 

electro-magnet, by which a lost tool may be drawn out of a niche in 

the drill hole and recovered. The electro-magnet has been used successfully by Mr. Phillips, of the firm of Phillips & Worthington, 

New York City, in drilling a well in· New Jersey, but the rigging up 

of the apparatus is expensive and difficult. · 

Rope spear.-If the cable ha.s broken near its connection with the 

temper screw and has fallen into the well it may perhaps be withdrawn by catching it with a rope spear (fig. 204 ), a rod armed with 

upward pointing barbs, which is lowered into the well by a rope. 

If the drill is wedged in so tight that the cable can not be withdrawn 

by the spear a rope knife (fig. 205 ) is lowered, by which the cable 

is cut off as near as possible to the drill. The drill may then be 

withdrawn by a slip socket apd the cable speared and removed. 

Defecti-ve casing.-Two instruments that are frequently used in 

dealing with defective casing are illustrated in figure 206-7 • If the 

casing has been dropped to the bottom of the well from a considerable 

height, it may be bent, or even twisted like a corkscrew, so that it 

can be withdrawn only in short sections. To do this the casing cutter 

(fig. 206 ) is inserted, the knives of which expand as the pipe on which 

it is screwed is rotated, and the casing is cut at any desired point. 

If the casing is only slightly bent it may be straightened by the 
106 WELL-DRILLING METHODS. 

use of a pipe swedge (fig. 207 ), dropped into it· repeatedly In the 

manner in which the drill is operated from the walking beam. 

REDRILLING AND ENLARGING. 

If the methods just descri.bed are ineffective in removing the broken 

parts, the driller may shift the drilling tools a few inches to one side 

and redrill and enlarge the hole. By drilling some distance below 

II 

7 

2 3 4 5 8 

FIGURE 20.-Fishing tools used with standard drilling outfit. 1, Spudding spear; 2, 

slip socket for tools ; 3, horn socket ; 4, rope spear; 5, rope knife ; 6, casing cutter; 

7, pipe swedge; 8, slip socket for inside of pipe. · 

the level of the top of the lost tools and spearing them out into the 

new hole, part of them may usually be grasped by a slip socket and 

withdrawn. If the drilling is done in relatively soft material the 

tools may be pushed to one side and passed by, thus drilling a second 

hole. This at first seems to be an almost impossible operation, but 

it is easily done, and is effective in disposing of even large broken 

instruments. 
DIFFICULTIES IN SINKING WELLS. 107 

GEOLOGIC DIFFICULTIES. 

SPALLS. 

Spalls of rock or loose stones may fall from the wall of the hole 

on top of the drill and wedge it in so tightly that it can not be withdrawn by cable pull alone. This is a common accident in wells in 

highly creviced or fissured rock or in glacial till, without casing or 

drive pipe. The spalls or loose stones may usually be broken up by 

a smaller drill, and the tools can then be withdrawn. 

In brittle sandstone and in shale the top of the string of tools may 

become jammed in a cavity in the wall of the well, made by the detachment of rock fragments. It is then necessary to bring the string 

of tools into their normal position in the drill hole by means of the 

spudding spear. They can seldom be loosened simply by playing on 

the cable. 

BOWLDERS. 

An incident that shows the close dependence of drilling on geologic 

conditions is the mistaking of a bowlder for bed rock. Ordinarily 

the driller determines whether the hard rock which the drill has 

struck is or is not a bowlder by noticing whether it seems loose and 

rebounds under the stroke of the drill. If it does not seem to be 

solid rock he endeavors to break it to pieces and remove it. 

The bowlder may be so large that the driller mistakes it for bed 

rock, and after drilling into it for 3 or 4 feet sets the casing in the 

bowlder, substitutes a smaller drill, and proceeds as if he were in bed 

rock, but after drilling a few :ieet farther he again encounters sand or 

clay of the same character as that above the bowlder. He must then 

draw the casing set in the bowlder and ream out the hole to a size 

which will enable him to sink the proper casing through it. 

The error of mistaking a bowlder for bed rock may be avoided by 

observing the drillings brought up to the surface and noting whether 

they are of material like the bed rock in the vicinity. In northern 

Indiana, fop example, a driller may be pretty certain that if the drillings indicate granite, or schist, or trap, the drill is in a bowlder and 

not in the bed rock, which in that region is for the most part limestone. If the rock appears to be a bowlder, he will of course expect 

to find soft material below it and will proceed accordingly. 

In the glaciated regions of North America the bed rock is overlain 

by a bed of till that ranges in thickness from a few feet to several 

hundred feet and contains many large bowlders. The bed rock in 

most places is shale, sandstone, or limestone, but the bowlders, having 

chiefly come from the north where the rocks are of different character, are chiefly of granite, schist, and other crystalline rocks; some 

bowlders, however, as those derived from the country rock, are of 

limestone and sandstone. · 
108 WELL-DRILLING METHODS. 

I£ a bowlder is especially hard, it may be blown to pieces by dynamite or rock powder tamped with a bushel or two of dry sand or clay. 

This may split the bowlder so that the casing will pass down between 

the broken parts, or it may break it into pieces so small that they can 

be further reduced by the drill and removed by the bailer. I£ the 

bowlder is to be broken by explosion, the casing should be drawn 3 

or 4 feet above the charge, so that it will not be injured. 

RUNNING MUDS AND CLAYS. 

Mud produced from some shales hardens quickly when exposed to 

the air. I£ such mud runs into a well and fills the space between the 

drill and the well wall, it may solidify and interfere with the withdrawal of the drilling tools. A hole drilled through a stratum of 

such shale must be cased down and drilling must be pushed forward 

so rapidly that the mud will not have time to solidify. The drill 

may be freed from obstruction by this mud and withdrawn by slowly 

working it up and down so as to gain on the upstrokes, and the mud 

may be removed by small buckets or augers. If this method fails, 1}-

or 2 inch pipes may be lowered into the well and the hardened mud 

and sand may be flushed out by a powerful water jet. Such a layer 

of mud and clay can sometimes be passed by casing it off with a short 

length of pipe and using a smaller drill, but the driller usually prefers 

to work patiently past it rather than to reduce the size of the hole 

by casing it off. 

Even if only a small quantity of water is present, clay will" crawl" 

and relieve pressure by squeezing through very small openings in 

threads or sheets. The slow but forcible movement of plastic clay 

into a drill hole may fill the hole during a single night when drilling 

is suspended. When drilling is resumed the next morning the drill 

will strike this soft plug of clay and ram it down until the compression of the air below prevents its further movement. The drill may 

continue to pound on this elastic cushion for days, or even weeks, 

without making further progress while the clay slowly accumulates 

in the hole. The difficulty may be overcome by casing off the clay 

before it forms a plug or by jetting through the plug. Plastic clays 

are encountered in South Dakota ancl. in the Atlantic coastal plain, 

but most of the glacial clays are so sandy that they yield readily to 

the drill even if the well does become clogged. 

QUICKSAND. 

Character of the material.-In drilling water wells in the soft 

coastal-plain formations that stretch from Cape Cod westward and 

southward along the border of the continent the most serious difficulty encountered is caused by beds of quicksand, which are as a rule 
DIFFICULTIES IN SINKING WELLS. 109 

interstratified with beds of coarser sand and of clay. The quicksand 

comes into the drill hole and must be bailed out in large quantities 

before the casing can be driven farther down and drilling continued. 

Under ordinary conditions quicksand will not yield its contained 

water, and therefore if it has a tendency to rise in the pipe the difficulty can seldom be obviated by pumping alone. The whole mass is 

saturated, its water can not be separately withdrawn, and it exerts 

practically hydrostatic pressure. 

A driller in the Northern States may find pockets or lenses of clay 

or coarse sand in a quicksand layer, and these cause him to think he 

has passed through the quicksand. Coarse sand, such as" bar" sand, 

will not rise if the velocity of the water through it is less than about 

2} feet per minute. The drive pipe shuts off the water and quicksand above such a pocket of coarse sand or clay, but as soon as the 

drill penetrates the pocket the quicksand flows in and may rise to the 

height of the top of the deposit. If the bed is 20 feet or mor~ thick, 

the pipe can not be driven through it on account of the resistance of 

the compact sand; and if the water in it is under great head, so as to 

force the sand up to or above the point at which the bed was struck, 

further progress may be almost impossible. In some wells quicksand 

has risen in the pipe 100 feet above the depth at which it wasstruck. 

Pressure of material.-If the drill hole is not kept full of water, the 

pressure exerted by quicksand on well casing may be very great. Experiments have shown that quicksand saturated with water exerts 

a lateral pressure equal to one-half its vertical pressure. Beyond the 

point of saturation the pressure is hydrostatic, the vertical and horizontal pressures being equal. Quicksand can be confined only by 

nsing ·water-tight casing, for it is commonly so fine that it will pass 

a standard 100-mesh sieve. Saturated material of this fineness will 

flow wherever water flows. The lateral pressure of quicksand is 

exceeded only by that of clay, and the clay moves much more slowly. 

vV ithdrawing tools.-"\Vhen quicksand is encountered not only does 

the material require laborious excavation, but unless the drill is withdrawn rapidly it gets jammed in the hole and is buried by the sand. 

The driller is then under the necessity not only of cleaning out the 

hole, but also of recovering the drill before he can resume drilling. 

In this event it is usual to bail out the quicksand to the point at 

which the drill is stuck and then introduce into the well a wash pipe 

an inch or two in diameter. With this the quicksand is agitated (or 

jetted) and washed down to the surface. This operation continues 

until the drill is partly free, when a slip socket is inserted over its 

upper end and, with the assistance of the fishing jars, it is jerked 

free from the quicksand. 

In connection with the up-and-down motion given to the drill 

while it is being removed from the quicksand, it must be raised with 
110 WELL-DRILLING METHODS. 

each stroke, and in this way gradually freed. The same method of 

procedure is required where quicksand comes into a well suddenly, 

the drill being moved up and down as .. if it were cutting into rock, 

while at the same time it is lightly raised at each upstroke. This 

operation must be carried on rapidly, otherwise the sand will pack 

about the drill and prevent its removal. 

If the driller is working in sand of rather fine texture, he draws 

the drill at night, as otherwise the sand may creep up around the 

drill and " set " almost as hard as rock. The drill is seldom left in 

the well overnight on account of the danger from sand or of malicious cutting of the rope, or, in a rock well, of having a bowlder 

fall and become jammed between the drill and the well wall. 

Penetration of quicl~sand.-If the layer of quicksand is only a few 

feet thick it may be penetrated by bailing out and then driving the 

casing. The pipe is driven as far as possible into the bed without 

bailing, and the quicksand may occasionally be passed through at one 

drive. 

A thin bed of quicksand that lies near the surface may be shut 0ff 

by driving sheet piling around the mouth of the well. 

Difficulty caused by quicksand may be partly overcome by filling 

the bottom of the well with mortar or Portland cement, which sinks 

down through the quicksand and sets. The hole may then be drilled 

through the cement, which forms a wall that prevents the further 

inflow of quicksand. Stones, clay, and asphalt have also been 

dropped or poured into the hole to restrain the quicksand, with some 

success. 

TVater pressure.7 The head of the water in quicksand is nearly always less than the elevation of the well mouth. Some drillers maintain that quicksand can always be penetrated by keeping the drill hole 

full of water. If the quicksand lies at a depth of seyeral hundred 

feet and its head is 100 or 150 feet below the surface, a column of 

water in the well will exert a back pressure on the quicksand of 43.4 

pounds per square inch for every 100 feet of drill hole, which will 

prevent it from rising in the pipe. The sand bailer may then be inserted and the well may be bailed through the column of water. 

It sometimes happens that after bailing out large quantities of 

quicksand the pipe becomes bent, a fact that is explained by assuming 

that the quicksand bailed out is removed from beneath a higher layer 

of firmer material, such as till or clay, on only one side of the pipe, 

and that the pressure of this material against one side of the lower 

end of the pipe causes it to be thrown out of alignment. The remedy 

consists in keeping the hole full of water. This prevents the formation of such an artificial cave; or if the pipe has already become 

crooked, corrects the trouble by causing the pressure on the pipe to be 

equal on all sides. 
DIFFICULTIES IN SINKING WELLS. Ill 

If such a cave is formed beneath a layer of till, bowlders may fall 

down from its walls and become jammed against the pipe and prevent 

it from being driven ahead. The side pressure caused in this way may 

likewise be at least partly overcome by keeping the hole full of water. 

If the trouble is not remedied by this means, the process may be supplemented by drawing the pipe until the drive shoe is above the 

bowlder. The bowlder may then be crushed with the drill and the 

pipe driven ahead. 

Pumping.-By keeping the shaft full of water, J. E·. Bacon, in 

sinking a large open well at Charlotte, Mich., in 1904, removed quicksand by a powerful sand centrifugal pump. This method was also 

successfully employed at Millville, N. J., in sinking a well 8 feet in 

diameter to a depth of 36 feet, the lower 16 feet being through fine, 

saturated sand.a 

Freezing.-Quicksand has been penetrated by shafts by means of 

freezing. This method was first employed in 1883 by F. H. Poetsch, 

a German mining engineer, who by using it sunk a shaft in a mine 

near Schneidlingen, Prussia, through a bed of quicksand about 18 

feet thick, lying about 100 feet below the surface. As other methods 

had proved unsuccessful, Poetsch drove pipes into the quicksand and 

circulated through them a refrigerating brine which froze a wall of 

quicksand 5 feet thick around the proposed shaft. Excavation was 

continued within this wall, and the shaft was carried downward 

through and below the quicksand. The same engineer later excavated 

through 107 feet of quicksand by the same means. The process has 

also been used in this country in sinking a number of shafts, one of 

which is described by D. E. Moran.b The machinery used in freezing the quicksand consisted of the following essential parts: 

1. An ammonia compressor or pump with suitable motive power. 

2. Pipe coils surrounded by constantly changing cooling water. In 

these coils the compressed and heated gas coming from the ammonia 

compressor is cooled to such a temperature that, at the pressure existing in the coils, it condenses to. the liquid form. 

3. A valve, regulating the flow of the liquid ammonia from the 

above-described coils into4. A second set of pipe coils, surrounded by brine or other vehicle. 

The liquefied ammonia passes from the regulating valve into these 

coils and immediately expands, absorbing the necessary heat from the 

surrounding brine. From the coils the gas is led back to the compressor, completing the cycle. 

The brine used was a 60 per cent solution of the impure calcium 

chloride of commerce. The c~lcl brine was pumped from the refrig- . 

a Ledoux, J. W., Eng. News, Mar. 12, 1903, p. 237. 

b Moran, D. E., The freezing process as applied at Iron Mountain, Mich., in sinking a 

• shaft through quicksand: School of Mines Quart., vol. 2, 1890, pp, 237-254. 
112 WELL-DRILLING METHODS 

erating tank through a system of distributing pipes and regulating 

valves to the ground pipes, and after circulating through these it 

returned to the refrigerating tank, the velocity of the brine in the 

downward flow pipes being about 2 feet a second. No protection 

was given to the connecting pipes above ground, so that these were 

soon covered over with a snow-like ice, the result of condensation 

from the atmosphere, and this served as a cheap and effective lagging. 

Soon after the brine was started· in circulation the ground began to 

freeze around each pipe, forming frozen cylinders, which increased in 

diameter until at the end of six days adjacent cylinders intersected 

and made a circular wall extending from the surface to the bottom of 

the drive pipe and thus formed a cofferdam inclosing the proposed 

shaft. Excavation was then begun inside this cofferdam, and no 

water came through the frozen wall at any time. The rate of freezing differed in different parts in the deposit, depending on the amount 

of water the parts contained. The smaller the amount of water the 

longer it required to effect freezing. 

Some of the physical qualities of the frozen quicksand were noted. 

JJ'rozen quicksand may be regarded as a mortar in which the cementing material is ice, and, as in a cement mortar, the strength will probably be found to 

depend on the quality of the sand and the presence of sufficient cementing material, as well as on the strength of the cement. 

Frozen quicksand looks like a fine-grained sandstone. It is perfectly homogeneous, breaks with a tendency to conchoidal fracture, and is as hard to work 

as a stone of similar character. ·when mixed with gravel or bowlders the mass 

resembles conglomerate or a concrete made with similar stone. The difficulty 

of working the material is more than doubled by the presence of gravel, which 

greatly increases its density and dulls the pick points or "moils" of the miners. 

The strength with which the quicksand adheres to the stone is shown by the 

line of fracture in such rna terial. There seems to be no tendency for the 

rounded bowlders to pull out of the quicksand, but rather for the break to 

follow the shortest line, whether through flint or quicksand.a 

Quicksand beds that lie near the surface can be thus frozen without very great expense, but the expense of freezing beds that lie at 

depths of over 100 feet will probably be great and the process will be 

slow. 

FLOODING OF OIL WELLS. 

DEFINITION. 

Irremediable injury is constantly being wrought in both old and 

new oil fields by "flooding "-the invasion of the oil or gas bearing 

stratum by water from some higher source.7) As water is heavier 

than either oil or gas, it displaces these substances or becomes mixed 

a Op. cit., pp. 248-249. 

b The term " flooding " is also used locally in another sense with reference to cleaning • 

wells (see p. 98). 
FLOODING OF OIL WELLS. 113 

- with them, and not only damages the well into which the water first 

enters, but also floods the contiguous sands and may result in the 

destruction of an oil district. 

CAUSES. 

Some oil men contend that the admission of water to beds of productive sands will affect the production of a well by raising the oil 

or gas above the level of the bottom of the casing, but the whole surface of the productive sands on the well wall is left exposed, and any 

rise of oil or gas in the sands themselves would not affect their relation to the well. 

In some wells flooding produces a mixture or emulsion of oil and 

water, which in the rock can only very slowly separate again under 

- the influence of gravity. 

Oil usually rests on salt water, and in order to keep the well in 

good condition as long as possible the oil should be pumped off the 

water slowly. In a state of rest the oil and the water are separated 

by gravity. The flow of oil from a_ well producing 500 barrels a 

day is so slow that it does not disturb the water, but if the amount 

is as great as 5,000 barrels a day the oil is drawn over the water so 

rapidly that the two are to some extent churned into an emulsion, 

and this effect probably extends some distance into the porous beds 

containing the oil. 

An emulsion is also formed if the well has been put down too far 

into the oil-bearing strata and the water level has risen by reason of 

continued and rapid outflow of oil. Forced production is often practiced, however, because it enables the owner of one well to draw oil 

from under his neighbor's property before his neighbor has had time 

to sink a well. In small fields this :forced production is important, 

because the oil is soon exhausted, and each well owner· tries to get as 

large a share of the supply as possible. 

Rapid pumping may exhaust a well and cause water to rise in 

the area around its lower end so as to flood adjacent wells and render 

them useless, as was shown in the fields at Chanute, Kans., at Humble, 

Tex., and some fields in Illinois. 

Rapid pumping may have the further disadvantage of making 

it necessary to store large quantities of oil at the surface, where 

25 per cent of it may be lost during a single summer by evaporation. 

The sand or rock originally holding the oil is its best reservoir, because it does not permit evaporation, and it furnishes the maximum 

yield. 

Well owners have apparently not realized the importance of considering the durability of well casing in connection with flooding, 

yet the decay of the casing is probably the chief cause of the trouble. 

65275°-W s P 257-11--8 
114 WELL-DRILLING METHODS. 

A well to which water has had no access for a score or more of years 

may be suddenly rendered useless by flooding caused by decay or 

break in the casing. It is more probable that by action of minerals 

in the water, chiefly iron sulphate, the pipe has been corroded and 

water allowed to come into the well. 

Another source of flooding may be an abandoned or" dry" wellone that does not yield oil or gas, but contains water. The hole may 

have been drilled into sands that yield oil at some near-by point, and 

unless the hole is properly plugged before it is abandoned water 

from it may enter the oil sand, find its way into neighboring wells, 

and cause great damage. 

Where the rock throughout an oil field is widely flooded, as fro'm 

abandoned wells whose locations even are no longer known, there 

seems to be no remedy for the flooding, either by pumping or by 

drilling deeper. 

PERMANENT EFFECTS. 

The permanence of the effects of flooding may be judged from the 

results of experiments made by a number of well owners. Mr. L. C. 

Sands, secretary of the Oil Well Supply Company, attempted over 

twenty years ago to restore a flooded area at Elizabeth, "\V. Va. The 

wells of the locality produced oil before the civil war at the rate of 

200 to 300 barrels a day, but when the war began they were abandoned 

and water accumulated in them. Mr. Sands purchased about 1,000 

acres of oil-producing land and attempted to pump the water off the 

oil sand. The pumping was continued for a long time, but the yield 

of oil was increased only about a barrel a day, and the experiment 

was therefore abandoned. 

Flooding is a serious matter. Again and again it is caused by the 

ignorance or carelessness of the drillers that first enter a field, who practically destroy all chance that it will ever be successfully exploited. 

"Wild-cat dril1ers '~ in a new field, who work rapidly and move 

from one place to another, frequently cause flooding, for they drive 

many wells that do not yield oil or gas and abandon them without 

casing off the water or properly plugging the wells. Even the casing 

may be withdrawn. Later, oil may be found near by and after being 

pumped for some time begins to show water, which has entered from 

the hole first drilled and flooded the sands-that is, has partly 

displaced the gas and oil. 

The term" wild-cat driller" is not used here in an odious sense, for 

the name is applied to one who drills in a locality where oil or gas has 

not been previously found-that is to say, to a driller engaged in 

exploration. The only odium attached to the name is caused by the 

inefficiency or carelessness displayed by some drillers in every locality. 
FLOODING OF OIL WELLS. 115 

STATE LAWS FOR PREVENTION. 

To guard against flooding, several States in which oil and gas :;tre 

found have passed laws making it an offense to abandon a drill hole 

without first plugging it with a wooden plug of a specified length, 

to be driven down by the drilling tools. The wood swells under the 

influence of the water and presses against the inner surface of the 

casing, firmly sealing it at the bottom. l\Iost of the laws prescribe the 

distance above or below the oil sands at which the plug is to be 

driven. 

If water fills the well to a considerable depth it is difficult to lower 

through it a plug of the required size, hence the plug is made in the 

form of a hollow cylinder, which is lowered to the well bottom, and 

a pin or plug is firmly driven into it by the string of tools. Several 

feet of earth are then thrown on top of the plug to complete the 

sealing process. If oil and gas are found at several horizons plugs 

must be inserted below the lowermost and above the uppermost 

horizon, and if a water-bearing stratum lies between oil and gas bearing strata this must be plugged satisfactorily both at its top and 

bottom. In addition the top of the well 1nust be closed by a plug. 

So far as the writer knows there is no officer whose duty it is to 

enforce this law, but prosecution is usually begun on the complaint of 

residents or well owners in the vicinity of a well that is abandoned 

or is to be abandoned. It is difficult to enforce the law because the 

evidence of the plugging can consist only of the word of the driller 

or contractor, and is impossible to discover by direct observation 

more than the approximate depth at which the plugs were placed or 

the manner in which they were inserted. 

A few of the statutes relating to the plugging of abandoned wells 

are quoted here, as they show the seriousness with which flooding is 

viewed. 

In Pennsylvania a law passed June 10, 1881 (sec. 1, P. L. 110), 

prescribes thatWhenever any well shall have been put down for the purpose of exploring 

for any producing oil, upon abandoning or ceasing to operate the same, the 

owner or operator shall, for the purpose of excluding all fresh water from the 

oil-bearing rock, and before drawing the casing, fill up the well with sand or 

rock sediment to the depth of at least 20 feet above the third sand or oilbearing rock, and drive a round, seasoned, wooden plug at least 2 feet in 

length, equal in diameter to the diameter of the well below the casing, to a 

point at least 5 feet below the bottom of the casing, and immediately after 

the drawing of the casing shall drive a round wooden plug into the well, at the 

point just below where the lower end of the casing shall have rested, which 

plug shall be at least 3 feet in length, tapering in form, and to be of the same 

diameter at the distance of 18 inches from the smaller end as the diameter of 

the well below the point at which it is to be driven [and] after it has been 

properly driven, shall fill in on top of same with sand or rock sediment, to the 

depth of at least 5 feet. 
116 WELL-DRILLING METHODS. 

Ohio has statutes equally specific, as follows: 

SEc. 306-4. It shall be the duty of the owner of any well drilled for gas or. 

oil and which in drilling shall have passed through any vein of mineral coal, 

before abandoning, or ceasing to operate such well, and before drawing the 

casing therefrom to seal the same in the manner following : There shall be 

driven in such well to a depth of at least 10 feet below the floor of the lowest 

coal measure a round seasoned wooden plug at least 3 feet in length and equal 

in diameter to the well at that point, on the top of which plug shall be filled 

at least 7 feet of sediment or drillings, or cement and sand. Where any gas or 

oil well passes through any gas or oil bearing rock lying above the coal measures, the owner of said well or his agent shall, upon abandoning or ceasing to 

operate such well, drive a dry wooden plug not less than 2 feet in length, equal 

in diameter to the diameter of the hole, to a point as near as possible to the 

top of the coal vein, on the top of which plug there shall be filled at least 5 feet 

of sediment or drillings, or cement and sand, as the mine inspector shall direct. 

In case such well is not plugged as afOresaid within ten days from the abandonment thereof, thJ chief inspector of mines or a district inspector of mines 

may cause the well to be plugged, and the costs and expenses of such plugging 

may be recovered of the person, firm, or corporation whose duty it is to plug 

the same, in the manner provided for the recovery of penalties by section 303-5 

of the Revised Statutes of Ohio. 

Indiana well owners are protected by the following statute: 

SEC. 651. PLUGGING ABANDONED WELLS. 2. Whenever any well shall have been 

sunk for the purpose of obtaining natural gas or oil or exploring for the same, 

and shall have been abandoned or cease to be operated for utilizing the flow 

of gas or oil therefrom it shall be the duty of any person, firm, or corporation 

having the custody or controi of such \Yell nt the time of such abandonment 

or cessation of use, and also of the owner or owners of the land wherein such 

well is situated to properly and securely stop and plug the same as follows: 

If such well has not been " shot " there shall be placed in the bottom of the 

hole thereof a plug of well-seasoned wood, the diameter of which shall be within 

one-half inch as great as the hole of such well, extend at least 3 feet above 

the salt-water level, where salt water has been struck; where no salt water 

has been struck such plug shall extend at least 3 feet from the bottom-of the 

well. In both cases such wooden plugs shall be thoroughly rammed down and 

made tight by the use of drilling tools. After such ramming and tightening the 

hole of such well shall be filled on top of such plug with finely broken stone or 

sand, which shall be well rammed to a point at least 4 feet above the Trenton 

limestone, or any other gas or oil bearing rock; on top of this stone or sand 

there shall be placed another wooden plug at least 5 feet long with diameter as 

aforesaid, which shall be thoroughly rammed and tightened. In case such well 

shall have been "shot" the bottom of the hole thereof shall be filled \vith a 

proper and sufficient mixture of sand, stone, and dry cement, so as to form a 

concrete up to a point at least 8 feet above the top of the gas or oil bearing 

rock or rocks, and on top of this filling shall be placed a wooden plug at least 

6 feet long, with diameter as aforesaid, which shall be properly rammed as 

aforesaid. The casing from the well shall then be pulled or withdrawn therefrom, and immediately thereafter a cast-iron ball 8 inches in diameter shall be 

dropped into the well and securely rammed into the shale by the driller or owner 

of the well, after which not less than 1 cubic yard of sand pumping or drilling 

taken from the well shall be put on top of said iron ball. (R. S., 1897, sec. 7888; 

R. S., 1901, sec. 7511.) 
CONTAMINATION OF WATER WELLS. 117 

The following law also makes it possible for others besides the well 

owner to remedy the defect and recover the cost of the labor and 

material: · 

SEc. 653. LIABILITY. Whenever any person or corporation in possession or control of any well in which natural gas or oil has been found shall fail to comply 

with the provisions of this act, any person or corporation lawfully in possession 

of lands situated adjacent to or in the vicinity or neighborhood of such well may 

enter upon the lands upon which such well is situated and take possession of 

such well from which gas or oil is allowed to escape in violation of the provisions of section 1 of this act, and pack and tube such well and shut in and 

secure the flow of gas or oil, and maintain a civil action in any court of competent jurisdiction in this State against the owner, lessee, agent, or manager of 

said well, and each of them jointly and severally, to recover the cost and expense 

of' such tubing and packing, together with attorney's fee and cost of suit. This 

shall be in addition to the penalties provided by section 3 of this act. (R. S., 

1897, sec. 7890; R. S., 1901, sec. 7513.) 

CONTAMINATION OF WATER WELLS. 

USUAL METHODS OF PREVENTION. 

In water wells less care is exercised in packing, plugging, and 

casing than in oil or gas wells, though the neglect may have serious 

sanitary results even if it is of less obvious economic importance. 

The water in water wells may be contaminated and rendered unfit 

for use by allowing water from other sources than those yielding 

desirable supplies to enter the well. If the well is sunk to a waterbearing bed whose water is made unfit for use by a large content of 

dissolved minerals, the undesirable water may be shut off by plugging 

the well above the point where such water is encountered, so that only 

the shallower supplies will be drawn upon. For this purpose it is 

customary to use a wooden plug, which expands under the action of 

the water and fits the well tight. Earth is then thrown on the plug 

and compacted, and when the- plug has decayed the earth itself 

prevents further trouble. 

In drilling a well water may be found at several levels, one of 

which yields unpalatable water, and it is then desirable to separate 

the different water-bearing beds and determine the source of the 

undesirable water. By the proper arrangement of pipes, packers, 

and plugs, each water-bearing bed can be separated fron1 the others 

and examined, and when the undesirable bed is located water from it 

can be excluded by casing it off. 

EXAMPLES OF CONTAMINATION. 

At a number of places in South Carolina water has been obtained 

by sinking deep wells, uncased below bed rock, into the fissured crys-
118 WELL-DRILLING METHODS. 

talline rocks that lie below the soil layer. Of these wells L. C. Glenn 

says a: 

The deeply drilled hole has cut across enough such fissures to obtain a large 

supply of water for the pumps, yet this \Vater is derived not from a great depth 

nor from a long distance, but from the great body of ground water near the surface and immediately around the well. If the fissures in the solid rock are 

very numerous, the area supplying the water is an inverted cone whose apex is 

the lowest point of entry in the bore hole and whose base is a large circular area 

of the ground-water surface around the well mouth, and only one, two, or three 

score feet beneath the surface of the town, with its innumerable sources of pollution of every kind. If the well is supplied by only one fissure or by a few 

fissures, they must be correspondingly large and furnish more direct and easy 

lines of flow to the well. They may extend almost uninterrupted nearly up to 

the surface and furnish a direct channel for surface waters to enter the well. 

The amount of water that can be pumped from such wells is usually large and 

analyses made when the well is first completed have shown a good, pure, clear, 

and usually soft water, well adapted to almost any purpose. But while at first 

such deep wells may be protected from contamination by the surface-soil layer, 

which acts as a filter, and the water may be pure and wholesome, yet they are 

very apt sooner or later to become contaminated. Constant pumping from them 

soon causes the indrafts supplying the water to open better channels through 

the fissures and allows more direct ingress of waters from the surface. These 

channels sooner or later are able to carry surface contamination directly into 

the well. Snell deep wells are therefore at best open to grave suspicion and 

constantly need careful watching. This need is all the more necessary because 

of the fancied security given by the very favorable analysis of the water when 

first used. Such careful watching will usually result in the condemnation and 

closing of the well in a few years, especially if the town be of considerable size, 

so that there is furnished to the soil a large amount of contaminating organic 

material. A well of this kind drilled over 2,000 feet deep in Atlanta, Ga., some 

years ago, which at first furnished a large amount of acceptable water, was 

ordered closed by the board of health after a few years' use because of sewage 

pollution. 

Two specific illustrations of the contamination of water wells have 

been furnished by the late J. E. Bacon, hydrologic engineer, as a 

result of experiments made to improve the water supply of Saginaw, 

Mich., and Dallas, Tex. 

Previous to 1902 a part of the city supply of Saginaw was drawn 

from a deep-well system consisting of about 20 bored 4-inch wells, 

having depths ranging from 89 to 230 feet. These wells, most of 

which penetrated bed rock, were being contaminated by the infiltration of brine from abandoned salt wells. Up to the time Mr. Bacon 

began his investigations almost no attempt had been 1nade at Saginaw 

to protect ground water from contamination of this kind. The 

seriousness of the situation may be understood from the fact that 

possible sources of ground-water supply at Saginaw are limited to the 

loose sands and gravels that overlie the rock and to the upper layers 

of the rock itself. Manifestly the only way in which this water can 

a Underground water of South Carolina : Water-Supply Paper U. S. Geol. Survey No. 

114, 1905, pp. 143, 144. 
CONTAMINATION OF WATER WELLS. 119 

be kept pure is by plugging abandoned salt wells at a suitable distance below the surface and by exercising great care in maintaining 

the casing o£ other wells intact. The contamination has been partly 

remedied and purer water is obtained for municipal purposes from 

the glacial sands and gravels that overlie the sandstone. 

At Dallas,. Tex., water is yielded by four geologic formations.a · 

One of the city wells penetrates a formation (the third in downward 

sequence) whose water has a high temperature and is so strongly 

mineralized as to be extremely unpalatable and unfit for domestic supply, though it is somewhat used for niedicinal purposes by a number of 

the residents of the city. This water is so corrosive that casing that 

had been in the well only one year showed many breaks and checks, 

several of them half an inch in diameter. The threads at the casing 

joints were so completely destroyed that when an attempt was made 

to pull the casing each length was lifted out as if it had no connection 

with the piece below. As a tight casing it was practically valueless. 

As the water in this formation is under greater head than that in the 

next water bearer above, the sands of the latter were becoming impregnated with the mineral substances contained in the lower water. 

By inserting a packer in this well between the two formations, with 

piping to the surface, the two waters were separated, the mineral 

water coming up inside the pipe and that from the higher formation 

rising between this pipe and the well casing. Differences in head and 

in the quality and temperature of the waters were at once noticed. 

Although the water from the higher beds was at first notably mineralized, the mineral content decreased with continued use. 

RESULTS OF DEFECTIVE CASING. 

Iron pipe put into the ground in the form of a sewer is not expected to last more than ten to fifteen years, but if it is put into the 

earth in the form of a well casing it is usually tacitly assumed that 

it will last indefinitely. That casing suffers deterioration and decay 

and that it should be examined at intervals for resulting defects is, 

however, shown concli.1sively by its condition when it is withdrawn 

after having been in the earth only a short time. 

The life of a casing can not be definitely predicted, the rate of its 

decay depending on the special conditions in each well. Casing withdrawn from some wells fifteen to twenty years old has been found to 

be in fairly good condition except at the joints, though as a rule at 

this age it is too badly corroded to be withdrawn at all. 

Decay of the casing may result in admitting to a well, and thus 

polluting the supply, undesirable water that was originally cased off. 

Recasing the well then becomes necessary. 

a Hill, R. T., and Vaughan, T. W., Geology of the Edwards Plateau and Rio Grande 

Plain adjacent to Austin and San Antonio, Tex. : Eighteenth Ann. Rept. U. S. Geol. 

Survey, pt. 2, 1897, pp. 199-321. 
120 WELL-DRILLING METHODS. 

In artesian basins where many wells have been sunk the head may 

be greatly reduced and wells near the border of the basin may even 

be rendered nonflowing by allowing the wells to discharge continuously. To prevent this needless tax on the underground supply, a 

number of States have passed laws prohibiting the waste of water 

from flowing wells and requiring the owners to provide means for 

closing the wells when the water is not needed. Even where such 

precaations are taken, however, much water may be lost through 

defective casing, which allows leakage into shallower porous beds. 

RECOMMENDATIONS. 

The vital character of the problems involved in water-well pollution should lead to the following definite procedure in sinking 

important wells: 

1. An accurate log of the well should be kept, so that the depth and 

character of the water-bearing formations may be known. 

2. Every water-bearing layer should be carefully examined as to 

its thickness and the quality of the water it yields. 

3. The head of water of each water-bearing layer and its relation 

to other water encountered should be accurately determined, so that, 

if necessary, contamination may be prevented by using packers ·and 

separate pipes for each water horizon. 

4. The casing should be intact when the well is completed, and 

should be kept so in order that it may fulfill its duty in shutting out 

undesirable water. Its condition should be determined from time to 

time by suitable experiments. 

5. The possible effects of defective casing should always be considered in interpreting a change in the head or the quality of the 

water. 

6. In those States in which the geological conditions favor contamination of underground-water supplies, the examination. of the 

well casing and the determination of the relations of separate waterbearing beds should be imposed by law on each well owner or well 

driller. 

7. In States where flowing artesian water is obtained, laws should 

provide for the closing of flowing wells when they are not in use, so 

that the artesian basins may not be needlessly drained. 

CAPACITY OF WELLS. 

SIMPLE TESTS. 

The testing of the capacity o~ a water well is the duty of the 

driller and is considered an essential part of the sinking of a well, 

especially as tests must occasionally be made while the well is being 

drilled. Wells sunk by percussion methods may be tested by bailing 

rapidly ~ith a bailer or sand bucket, the capacity of the bailer and 
CAPACITY OF WELLS. 121 

the time during which the test is conducted being known. The 

larger wells may be tested by means of a centrifugal pump, and many 

small wells are tested merely by attaching a hand pump and pumping 

rapidly for several hours. _ 

The proper testing of a well, however, involves also a knowledge 

and interpretation of the geologic structure as revealed by the boring. 

In many parts of New England the rocks consist of schists, gneisses, 

and granites, and the structure is so complex that conditions are 

extremely unfavorable for procuring water by deep wells. The water 

supplies obtained are chiefly from the streams or from the ground 

water in the decayed upper portion of the crystalline rocks. Some 

of the drillers and many of the well owners in this region believe t~at 

sufficient water may be obtained if only the wells are drilled deep 

enough. But sometimes a driller who realizes the fallacy of this 

belief nevertheless fosters the idea in the mind of the owner and 

drills a well 400 or 500 feet deep into "dry" rock. The surface 

water drains into it, and the " test " consists in pumping accumulated 

surface water from a deep drill hole. 

A test of this character which was conducted -under circumstances 

that make the naming of the specific locality inadvisable is here cited, 

because it affords a by no means isolated example and because its 

mention may prevent a repetition of the trick. The well had been 

drilled 350 feet deep and the suction pipe was extended nearly to the 

bottom of the well. The well was tested by a steam pump for ten 

or fifteen minutes, until the surface water was exhausted, when the. 

driller always found some excuse for stopping the engine. By the 

time the imaginary difficulty was overcome sufficient surface water 

had again acci1mulated in the bore hole to permit steady pumping 

for several minutes more. The well owner was satisfied with the 

test and was about to accept the well when his attention was called 

to the conditions. On insisting that the well be pumped continuously 

for several hours he discovered the source of the water and its small 

amount. 

TESTS OF FLOWING WELLS. 

Other phases of the testing of water wells have been discussed by 

Chamberlin. In speaking of the defective flow of artesian wells, he 

says: a 

It is possible, in perfect honesty, to make both a negative and a false test. 

Suppose that two porous beds, A and B [fig. 21], separated by an impervious 

layer, are traversed, and the testing of the first has been neglected, either 

because it failed to giYe encouraging indications or for other reasons. It is now 

desired to test these. Suppose the seed bag or rubber packing be placed above 

the upper one. Now, if both bear a water level equally high the test will be 

fairly made and the result will indicate their combined capacity; or, if both 

a Chamberlin, T. C., Requisite and qualifying conditions of artesian wells: Fifth Ann. 

Rept. U. S. Geol. Survey, 1885, pp. 160-162. 
122 WELL-DRILLING METHODS. 

heads are at least as high as the surface at the well, the test may be accepted. 

But suppose that the bed A has been cut into by erosion or been reached by 

crevices or is otherwise defective, while the other, B, remains intact and bears 

an elevated fountain head. Under these conditions the 

water may flow from B through the bore into A and escape 

laterally &rough it, as illustrated in the figure. Now. in 

this case the result may be either simply negative [fig. 21] 

or positively false and misleading [fig. 22]. If the lateral 

leakage through the stratum A effectually disposed of the 

flow from B, and there was no leakage in the upper portion of the well, the water in the test tube would stand 

during the test at essentially the same height as before, 

and the result would be negative, merely failing to indicate a possibility that really existed. If, on the other 

hand. there was lateral leakage through the upper strata 

as well as through A, neither alone 

being quite competent to dispose of 

the flow from B, then the introduction of ~he test pipe would cut off the 

upper leakage, leaving the bed A unable to dispose of the entire flow. In 

this case there would be a rise of 

water in the tube and possibly a flow. 

FIGURE 21.-Section The mischievousness of a test of this 

of a well illustrating a negative test. sort lies in the fact that it appears to 

be a true test, because it shows some 

result, while in reality it is false and misleading. The 

true test in this case can only be made by placing the packing between the porous beds A and B. 

FIGURE 23.-Section of 

a well illustrating an 

inverted test. 

Take another instance where two 

porous beds, as A and B, figure 22, 

have been traversed. Let the packing be placed between these. Then 

(1), if A equals B in productive capacity, water will stand at the same 

height within and without the test FIGURE 22·-Section of a well illustratpipe if there is no leakage in the 

upper beds. (2) If the failure to 

flow was due to such leakage, then a 

ing a partial and 

misleading test. 

flow will result from B, but the additional flow which 

might be secured from A is lost. ( 3) If A has a greater 

head than B, and if there is no loss above, the water in the 

test pipe will actually be lower than that outside, as illustrated in figure 23. This may be said to be an inverted 

test and is less misleading than the false and negative 

tests, since it plainly indicates an error of manipulation. 

I have known such a case of reduced head as the result 

of an attempted test. ( 4) If, however, there is in this 

case considerable lateral waste in the upper strata, the 

valuable flow from A will be lost just as before the test 

was made, while B may give a rise in the tube, or even 

a flow, which would foster the impression that a fair test had been made, 

while in reality the greater flow has been lost. (5) If A gives a feebler flow 

than B, buthas an equal head, the test will fail of being completely satisfactory 
CAJ? A CITY OF WELLS. 123 

only in excluding the feebler flow from A. (6) If, however, A has a lower head 

and is a possible means of escape from the flowage from B, then the packing 

has been placed at the right point and the test gives the best results. 

3. In still another case let A and B represent porous beds, the lower of which 

is so conditioned as to drain the upper one by virtue of a lower outcrop. (1) 

First, if the draina.ge loss below is not complete, and if the packing is placed 

above A, as shown in figure 24, I, the result will be negative if there is no leakage in the upper strata. (2) Should there be considerable loss there it will be 

cut off by the tube and packing, and some rise in the tube will be the result in 

most cases. In either instance the result is misleading, particularly in the last, 

because the small rise of the water is apt to allay any suspicion as to the 

effectiveness of the test. The real fact, however, remains that the flow from the 

productive stratum is mainly lost below. (3) Suppose that the packing is located between A and B, as in figure 24, II, it will then shut off the flow from A, 

while that in B, because of a lower outlet, will fail to flow. Now, if there is 

opportunity for lateral leakage in the upper strata, the water from A will rise 

in the well outside of the test pipe and pass off into these open upper beds. 

( 4) But if no such opportunity is afforded it may rise to the surface and overflow outside of the test pipe, while the water within the test pipe will probably 

be found to be lower than before the test was made. The proper method of 

testing wells known or suspected to present these conditions is to sink a simple 

bag of seed or other obstruction to a point in the impervious stratum between 

FIGURE 24.-Section of strata showing one correct and two erroneous tests. 

A and B, which, when it tightens in its place, will shut off the flow below. Then 

a tube with packing sunk at a point above A will effectually cut off all leakage 

in the upper strata, and the full capacity of the water bed A will be tested. 

These examples, while not exhaustive of possible cases, illustrate the nature of 

defective tests and the deceptive conclusions liable to be drawn from them. 

The remedy is manifest. Test each water-bearing stratum as it is encountered, 

or else vary the final tests so as effectually to exclude all liabilities to error. 

STORA.GE AND INFLOW CAPACITY. 

Water wells drilled to a depth of less than 200 feet are commonly 

cased with 2-inch pipe, as it is cheap and fairly effective, but it is apt to 

go crooked or fail to stand the strain of driving to greater depths. 

Water wells more than 200 feet deep are usually made 5~ or 6 inches 

in diameter. Such wells can be drilled to considerable depths more 

rapidly than smaller ones, because the tools are heavy and are not so 

liable .to break as are those used in sinking wells of less diameter. 

The larger pipes also make a larger reservoir for water. Usually 

sufficient space should be available to hold at least a barrel of water; 

and if the hole is of small diameter it must be drilled correspondingly 
124 WELL-DRILLING METHODS. 

deeper, will require more casing, pipe, and pump rod, and involve a 

heavier lift. 

The yield of a well depends on both the size of the hole and the 

supply. Boring is usually continued some distance below the point 

where water is tapped, in order to strengthen the supply, and the 

pump cylinders are placed some distance below the water level to 

allow for lowering this level by pumping. 

The larger well has another advantage where a stratum that yields 

undesirable water must be cased off. If the well is only 3 or 4 inches 

in diameter at the top, it is very difficult to continue drilling with a 

smaller bit after casing off the unde.sirable water, but if the top 

diameter is 5~ inches it may be easily reduced to 4 inches and the well 

continued until a desirable water-bearing layer is reached. In most 

water wells of moderate depth, therefore, except in the matter of 

original cost, the larger bore is found to be the most economical. 

In an oil well the size of the well has immediate bearing on the production of oil, for as the surface of the well wall varies directly with 

its diameter the production of the well is correspondingly greater 

with a larger bore. The production of a well often depends also on 

the size of the charge of nitroglycerin exploded at the level of the oilbearing sands, and the use of a larger bore allows a heavier charge 

and insures greater production. 

EFFECT OF FRICTION. 

When small drilling tools are used the friction, as compared wit~ 

the impact force of the drill, is greater than when larger tools are 

employed, for though the frictional surfaces increase directly with 

the diameter of the drill the proportionate increase in the weight of 

the drill varies as the square of the diameter. In other words, if the 

diameter of the drill is doubled the friction surface is also doubled, 

while the weight or impact force is increased fourfold._ For example, if the diameters of two drills are 8 inches and 4 inches, respectively, their friction surfaces, assuming the drills are of equal length, 

will be in the ratio of 8 to 4, while their volumes or weights will be 

as 64 to 16. If the larger drill is longer than the smaller one, or if a 

heavier string of tools is used with the larger drill, the proportionate 

increase in the impact force will be greater than is indicated above, 

while the proportionate increase in the friction will remain the same. 

Another factor in the friction problem is the steadiness of the drill 

in the hole. In this respect, also, the large, heavy drill has the advantage, as it is not subject to so great vibration as the small drill, and 

therefore produces a straighter hole. 
WELL-DRILLING METHODS. 125 

MEASUREMENT OF DEPTH. 

CABLE MEASUREMENT. 

In a well that is being drilled with~ a standard outfit the depth is 

usually measured by the cable or derrick method, the distance to the 

bottom of the well being obtained at any time by measuring the length 

of drilling cable as the tools are lowered into the hole. Just as the 

top of the tools are about to enter the hole, a string or a strand of rope 

is tied to the cable at the bull-wheel shaft. The tools are lowered 

until this string has gone up over the crown pulley and down to the 

well head, then another string is tied to the cable at the bull-wheel 

shaft, and so on until the tools reach the bottom, the last fraction of 

derrick height being measured by a 5-foot stick. The number of 

strings tied to the cable is then multiplied by the distance from the 

bull-wheel shaft up over the crown pulley and down to the well head. 

'This distance, added to the last fraction of derrick height, gives the 

total depth of the well. 

Errors in 1neasurement may be caused by the slipping of the string 

tied to the cable, by the stretching of the cable, or by miscount of the 

number of strings. Any one of these inaccuracies vitiates the record 

for scientific purposes. These errors are, of course, more likely to 

occur as the well becomes deeper. 

TAPE MEASUREMENT. 

The exact depth from the surface to the oil-bearing sands is a 

matter of more importance to the oil-well driller than the exact depth 

and thickness of each stratum passed through, because it is necessary 

to avoid error i;n selecting the position at which to place the torpedo, 

whose explosion is a matter of great importance in the yield of the 

well. Therefore, when the oil sands are reached the well is measured 

by a metal tape. This measurement is a delicate operation, since in 

some wells one-quarter to one-half mile of tape must be used, the 

weight of which is considerable, and even in a steel tape the stretch 

is sufficient to account for many errors of judgment. 

The measurement of a well with a steel tape has often been found 

difficult, on account of the magnetized condition of the well casing, 

which has been produced by the jarring of the drilling tools and 

which causes the tape to be drawn to the casing and held there, 

making a correct measurement impossible. To avoid the difficulties 

of magnetization a copper wire or tape may be used, as copper does 

not respond to the magnetic influence of the casing, and by its use a 

better determination of the depth can be made. 
126 WELL-DRILLING METHODS. 

BACON DOUBLE-CONE METHOD. 

An ingenious instrument has been devised by Mr. J. E. Bacon for 

measuring the depth and thickness of water-bearing strata. This 

instrument is shaped like a double cone, and consists of a central 

brass plate, over whose edge are drawn wires fastened at each end to 

a center post. To one end of this apparatus a line is attached. As it 

is lowered into the hole a steady stream of water under known pressure is forced down the well. This acts on the brass plate and produces a certain determinable tension on the suspending line. When 

a water-bearing stratum is reached the loss of water into it and consequent decrease of tension on the line as the instrument passes its 

upper surface at once indicates its position. A reverse change of 

slighter value as the instrument passes the bottom of the stratum in 

like manner indicates this second position. 

DEFLECTION OF DRILL HOLE. 

CAUSES AND RESULTS OF DEFLECTION. 

In beginning a well care must be exercised to make the hole perpendicular; otherwise drilling to a considerable depth is very difficult, if not impossible, because of the friction of the tools caused by 

increasing deflection of the hole. In order to keep the hole straight 

the driller may lengthen out the tools to 60 or 80 feet, the increase 

in length being obtained chiefly by using a long auger stem. Notwithstanding this precaution many holes go crooked, especially if the 

rocks are creviced, or schistose in structure, and the angle of schistosity is only a few degrees from the vertical, for the tools tend to 

follow the crevices or the structural planes. Under these conditions 

a hole may not depart greatly from the vertical during the first 1,000 

or 1,500 feet, but if this depth is trebled the cumulative result may 

be remarkable. 

Two examples of notable deflection may be cited here. One came 

under the writer's observation in the summer of 1905 at Casey, Ill., 

where a water well had been drined 3 or 4 feet from an oil well, the 

drilling of which had been delayed at the depth of several hundred 

feet by lack of water. The driller reported very hard rock at 80 feet, 

and shortly afterward oil came into the water well. As the rock at 

that depth contains no oil it was at once suspected that the deflection 

of the water well had resulted in the drill penetrating the drive pipe 

of the oil well, and on further examination this was found to be true. 

The deflection in this well was in the ratio of 1 to 40, and if this had 

been carried to a depth of 1,000 feet, the deflection of approximately 

25 feet would have been so great as to interfere seriously with deeper 

drilling. 
DEFLECTION OF DRILL HOI.JE. 127 

The second example, furnished by a hole in South Africa, is cited 

in an article by H. F. J\{arriott.a The hole was bored with a diamond 

drill on the property of the Turf Mines, Ltd., near Johannesburg. As 

a result o£ a large number of obseryations in the vicinity of the 

property, the average dip of the rocks was taken to be 26° and the 

strike as due east and west. Instead of going straight down, the hole 

was deflected northwest from a vertical line and turned more directly 

toward the north against the strata as sinking progressed. Measurements by an electrical instrument show that the hole was deflected 

2,185 feet away from the vertical in a N. 28° W. direction. (See fig. 

25.) The actual'vertical depth of the bottom of the hole, instead of 

being 4,802 feet as first recorded, was in realty only 3,910 feet. 

These examples indicate the great value if not the absolute necessity of making an accurate survey of deep bore holes; otherwise at 

depths of 3,000 or 4,000 feet the true position of oil or gas sands or 

other mineral deposits may not be definitely known. 

INSTRUMENTS FOR MEASURING DEFLECTION. 

Two styles of instrument have been devised for measuring the 

deflection of deep holes. One accomplishes this object by means of a 

compass needle contained in a case filled with a paraffin or other easily 

melted substance. After being lowered into the hole, the paraffin 

is melted by means of an electric current, and when sufficient time has 

elapsed for the needle to assume its proper position, the current is 

shut off and the paraffin solidifies and holds the needle in position. 

Errors in using this instrument have resulted from too rapid cooling 

of the paraffin, and, as· the instrument has to be withdrawn for each 

determination, the process is slow. 

In determining the deflection of the South African bore hole previously mentioned, a continuously recording instrument invented by 

Mr. Marriott was employed. This instrument consists essentially of 

a strong metallic cylinder containing a resistance coil, commutator, 

and pivoted switch arm. As the instrument is lowered the varying 

inclination moves the switch arm over the commutator so as to produce a varying resistance, which is indicated and measured by a galvanometer and resistance box placed at the surface in circuit with 

the instrument and with several electric cells of known electromotive 

force. By this means the position of the·switch arm on the commutator and hence the inclination of the instrument are determined. Satisfactory check readings ar~ obtained while withdrawing the instrument. 

a Marriott, Hugh F., Electrical devices for deep bore hole surveying: Eng. News, July 

27, 1905, pp. 91-94. 
128 WELL-DRILLING METHODS. 

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FIGURE 25.-Defiection of a diamond-drill hole in South Africa. 
WELL-DRILLING METHODS. 129 

COST OF WELL SINKING. 

Factors involved.-No other information connected with well sinking is so hard to obtain or, when obtained, is of so little general 

value as that relating to cost. In regions where many wells of a particular class have been sunk figures of cost may be fairly reliable; 

but where underground conditions are not so well known such information is more indefinite and is often withheld by drillers or contractors for business reasons. 

The cost of sinking wells is determined chiefly by economic conditions, including cost of labor, material, and transportation; by the 

size and depth of the well ; by the character of the material penetrated; and by the method of drilling employed. 

If a well is sunk in a rather inaccessible locality, where fuel is 

scarce and labor is high, the cost will, of course, be much greater than 

that of a well sunk by the same method through similar formations 

in localities where labor and material are cheaper and transportation 

charges are l~ss. . 

Increase in diameter of the hole not only increases the cost of 

sinking because of the additional material that must be removed, but 

it demands larger and more expensive tools and more power to operate 

them. The cost of each foot drilled increases rapidly with the depth, 

for more time is lost in changing the tools and cleaning the hole, and 

progress is slower because of the- decreased speed at which the tools 

must be operated. Greater labor and ingenuity are also involved in 

recovering lost tools and overcoming other difficulties. 

The rate at which sinking proceeds determines the time required to 

complete a well, and hence is an important factor in the total cost. 

The rate of drilling depends both on the material penetrated and 

the method of sinking employed. Drilling advances much slower in 

hard, tough rock than in more fri:able material, and even in plastic 

clays it is slow, as the material is difficult to penetrate. Quicksands 

also may cause trouble in some wells. vVith auger or jetting outfits, 

however, quicksands can be much more easily and cheaply penetrated 

than with other outfits. 

As the size of the parts and the number of accessory tools for the 

various rigs depend on the size of the hole to be sunk and the conditions to be met, the figures of cost here presented for the various outfits must be regarded only as approximating the price of the more 

usual outfits at or near supply points. 

Standard method.-The regular standard outfit, including rig, 

power, and tools, in the Pennsylvania oil fields costs from $1,700 to 

$3,000 or more. A 72-foot derrick with reels and ironwork costs 

$600 to $750. The boiler employed varies from 15 to 40 horsepower 

65275°-W s P 257-11--9 
130 WELL-DRILLING METHODS. 

and the engine from 12 to 30 horsepower, the size depending on the 

depth to be drilled ; the two cost between $600 and $900. The necessary tools usually cost about $500, though fishing tools and other 

extras may involve an aggregate expenditure for the outfit of as 

much as $4,000. 

The average cost of oil-well casing ranges from 40 or 50 cents a foot 

for 4-inch to about $2 a foot for 12-inch, though the price varies with 

the iron market and with the freight charges. 

In the Gaines oil field of northern Pennsylvania, where drilling 

sometimes proceeds at the rate of 70 feet in twenty-four hours, 

through shales and shaly sandstones and limestones, drilling is done 

by contract at about 65 cents a foot, the cost of casing being additional.a 

In the Coalinga oil district in California, where water has to be 

purchased and forms an extra item of expense, the average cost of a 

4~000-foot well has been estimated at $7,500, divided as follows: 

Labor and water, $1,500; casing, $2,500; outfit, $3,500.0 Many of 

the deep wells in this district, which start with a casing 11~ inches 

in diameter, greatly exceed this average cost, however. 

In the Summerland oil district of California wells 6 or ~ inches in 

diameter at the top and about 250 feet deep are put down at a cost of 

about 85 cents a foot for drilliJ)g only.c 

Portable rigs.-Portable rigs are much used for drilling water wells 

4 or 6 inches in diameter. A machine capable of drilling to a depth of 

1,000 feet costs about $1,100 with non traction power, and about $1,400 

with traction power, The tools for such a machine, exclusive of 

cables, cost $400 to $500 additional. Lighter machines, with a capacity of about 300 feet, cost about $700 with power, this amount being 

about equally divided between the machine and the engine and boiler. 

Tools and cable for such a machine cost $200 to $250 more.a 

The rate of drilling with portable outfits . varies. In shale, soft 

sandstone, and similar materials, 30 to 50 feet a day is a common 

record; in hard sandstone, 15 to 25 feet a day; and in clay and other 

unconsolidated material, 75 to 100 feet a day is a fair average. 

The cost of drilling wells varies from 10 or 15 cents a foot in the 

softer materials to $1 or more a foot in hard rock.e In the northern 

Mississippi Valley 4-inch and 6-inch wells in shale and limestone cost 

50 cents to $1 a foot for drilling only; in quartzite the cost runs up to 

$3 and $4 a foot.' 

a Twenty-second Ann. Rept. U. S. Geol. Survey, pt. 3, 1902, p. 605. 

b Notes of Ralph Arnold, U. S. Geol. Survey. 

c Bull. U. S. Geol. Survey No. 321, 1907, p. 65. 

d Net prices given in trade catalogues, 1906. 

e Statements of drillers. 

f Water-Supply Paper U. S. Geol. Survey No. 255, 1910, p. 35. 
COST OF WELL SINKING. 131 

In the hard,. tough lava of eastern Washington, where in some 

wells only 2 or 3 feet a day can be drilled, the drillers charge $2.25 to 

$3 a foot, fuel and board being furnished them.a 

The portable rig has been used in drilling shallow holes of small 

diameter for blasting or exploration purposes at a cost as low as 8 

cents a foot. b • 

Pole-tool method.-The figures of cost given -above also apply 

approximately to wells drilled with Canadian pole-tool outfits, for 

the chief advantage of the use of the pole-tool outfit in some parts of 

the country is its adaptability to drilling wet holes. 

Self-cleaning or hollow-rod method.-Hollow-rod tools are often 

used with a portable machine built for cable tools, the rods and other 

extras costing $150 to $250 for a capacity of 250 feet. Additional 

rods cost 25 cents to $1 a foot, depending on their quality. The common sizes are 1 to 2f inches in diameter. 

Machines built especially for hollow-rod tools, complete with horsepower attachment, tools, and 100 feet of rods, cost from $225 for 2-

inch outfits to $325 for 5~inch outfits. The price for a machine with 

a 5 or 6 horsepower engine and boiler ranges from $650 to $800. a 

The cost of drilling with hollow-rod tools does not differ greatly 

from that with small portable cable rigs under similar conditions, but 

no specific figures are at hand. It is, however, usually 20 to 30 cents 

a foot, without casing. 

California or stovepipe method.-Concerning the California or 

stovepipe method of well sinking, the following figures have been 

published. The machinery and power cost $1,500 to $1,800, and the 

tools and accessories $500 or more, additional; and a pair of hydraulic 

jacks cost $250.a The following tables show approximately the 

cost of sinking wells by this method and the cost of stovepipe casing. 

The latter cost, of course, varies with the price of steel. 

Cost pet· foot of drilling wells by the California or stovepipe method. 6 

4-inch. 5-inch. 6-inch. 7-inch. 8-inch. 

------------

First 100 feet .................... $0.30 $0.30 { $0.35-} so. 40 { $0.40- 0.40 0.50 

Additional for each 50-foot in- .25 { .20- .20- .20- crease in. d&pth .••............ .25 .30 .35 .35 

"Water-Supply Paper U. S. Geol. Survey No. 118, p. 60. 

"Statements of operators. 

c Net prices give'll in trade catalogues. 

" Stevens Institute Indicator, vol. 22, 1905, pp. 17-30. 

W-inch. 10-inch. 

----·--

$0.60-} 

0.65 $0.65 

.20-} 

.35 .35 

• Water-Supply Paper U. S. Geol. Survey No. 137, 1905, p. 32. 
132 WELL-DRILLING METHODS. 

Cost of riveted steel well ca8ing in 2-foot joints.a 

Diame- Gage. P<ke poe II Diamo- Gage. Price per Diame- Gage Price per ter. foot. ter. foot. ter. foot. 

Inches. ---,~ Inches. Inches. 

4 16 $0.32 7 16 $0.48 9! 14 $0.75 

4 14 .38 7 14 .55 9! 12 .94 

5 16 .35 8 16 .55 10 16 .68 

5 14 . 43 8 14 .64 10 14 • 78 

6 16 .42 

I 

8 12 . 78 10 12 .98 

6 14 .50 9! 16 .65 

a Water-Supply Paper U. S. Geol. Survey No. t::n, 1905, p. 32. 

At the prices given in the preceding tables a 6-inch well 500 feet 

deep, with casing, would cost between $750 and $1,000, assuming that 

the initial diameter is maintained all the way clown. 

The average rate of sinking wells by this method is 40 to 50 feet in 

a 10-hour clay. 

Hydraulic rotary metlwd.-The hydraulic rotary method of drilling, like the standard method, requires heavy machinery, and the cost 

of outfit is consequently high. In the Beaumont field of Texas the 

derrick costs about $125, and the machinery, including two boiler,s 

and two pumps, costs about $3,600.a For wells approximately 3,000 

feet deep a 30 to 40 horsepower boiler, 10! by 12 inch single-cylinder 

engine, and duplex pumps, with cylinders 10 by 5 by 12 inches, are 

commonly used. 

Water wells 400 to 1,000 feet deep and 6 to 8 inches in diameter 

have been put down in southern Arkansas with hydraulic rotary outfits for $2.50 to $5 a foot, including casing.b 

In the Beaumont oil field of Texas the contract rate for sinking by 

this method has averaged $4 to $4.50 a foot, including casing. In 

this region it takes about two months to drill a well 800 to 1,000 feet 

deep. 0 

Jetting method.-No figures are at hand as to the cost of jetting 

machines, but as the main parts of the outfit are a small derrick and 

a force pump the apparatus. is not expensive. 

In southern Arkansas 4-inch wells have been jetted down to a 

depth of 400 feet at a cost of $1 a foot without casing; in Louisiana 

smaller wells have been sunk at an average cost of 39 cents a foot.d 

In the Coachella Valley, in southeastern California, 4-inch wells are 

sunk and cased by contract to depths of 500 and 600 feet for $1 a 

foot.e In the coastal plain of southern California wells 2 to 4 inches 

in diameter and usually less than 100 feet deep are sunk by this 

method for 30 to 40 cents a foot, the cost of casing being aclditional.t 

a Letters from supply companies. 

b Prof. Paper U. S. Geol. Survey No. 46, 1906, p. 110. 

c Bull. U. S. Geol. Survey No. 212, 1903, pp. 169-170. 

d Prof. Paper U. S. Geol. Survey No. 46, 1906, pp. 108 and 109. 

e Statements of contractors. 

t Water-Supply Paper U. S. Geol. Survey No. 137, 1905, p. 32. 
COST OF WELL SINKING. 133 

OoTe d'l'ills.-Core drills are made in a number of sizes, from handpower machines of 300-foot capacity to electric or steam driven machines capable of boring to depths of 6,000 feet. 

The hand-power drill illustrated in Plate III, A, with accessories 

and 200 feet of rods, is listed at about $600, and the powerful machine 

shown in Plate III, B, with accessories and 2,000 feet of rods, is 

quoted ·at approximately $5,500. 

In 1906 the market price of carbons was $85 to $90 a carat. Since 

8 stones weighing 1 to 4 carats apiece are required for each bit the 

bits may cost as much as all the rest of the outfit. 

The wear on carbons is usually 30 to 80 cents a foot, averaging 30 

to 40 cents in moderately hard rock. The total costs of drilling in 

moderately hard material under ordinary conditions have been $1.50 

to $2.50 a foot for holes 11 to 1! inches in dia;meter.a 

Records of rates of drilling show an average in chert and quartz 

of 75 to 80 feet for a week of sixty hours; in basalt, sandstone, slate, 

and diabase, about 100 feet; and in limestone 150 to 200 feet. 

It is claimed that the cost of drilling with calyx and shot bits is 

less ·than that with a diamond bit under the same conditions, and 

that cores of larger diameter are obtained. 

When chilled shot are used, the consumption is one-quarter to threequarters of a pound for each foot drilled in soft rock, and 1 i to 4 

pounds in hard material.b 

Augers.-Hand augers to be used with common water pipe as extension rods are on the market, and range in price from about $5 for 

2-inch augers to $40 or $50 for 10 and 12 inch sizes. Horsepower 

machines capable of boring wells 100 feet deep and 40 inches in 

diameter are listed at about $200. 

Water wells 3 or 4 inches in diameter can be bored with hand 

augers at a cost of 25 to 35 cents a foot without casing; wells 6 inches 

in diameter have been sunk at a cost of about 50 cents a foot.c vVith 

the Arkansas clay auger, using horsepower, wells are put down at a 

cost of 12-! to 40 cents a foot.a 

Driven wells.-The cost of driven wells consists mainly in the 

outlay for drive point and strainer, pipe, and suction pump. The 

driving itself does not require expensive machinery nor skilled labor. 

A 1-!-inch drive point and screen costs about $2.50; 25 feet of 1-!-

inch pipe, about $3; and a pitcher ·pump, about $5; so that the cost 

of small driven wells should not be more than $15. 

a Articles in mining journals. 

b Statements in trade catalogues. 

c Prof. Paper U. S. Geol. Survey No. 46, 1906, pp. 109-110. 

d Op. cit., p. 95. 
134 WELL-DRILLING METHODS. 

SUPPLY COMPANIES. 

A list of the companies dealing in well-drilling machinery that 

have furnished information either by catalogue or by correspondence 

is given below. As there is unfortunately no trade journal devoted 

to well-drilling machinery and most of the firms handling such machinery do not f!dvertise in the engineering journals a complete list 

of American firms was not obtained. It is thought, however, that 

companies handling all the various kinds of well machinery are 

represented. 

List of drill manufact-urers and supply companies. 

Cook Well Company, St. Louis, Mo.-auger and well screen. 

Cyclone Drilling Company, Orrville, Ohio-portable drilling outfits. 

Ingersoll-Rand Company, 11 Broadway, New York City-calyx drill. 

Keystone Driller Company, Beaver Falls, Pa.-portable drilling outfits. . 

Loomis Machine Company, Tiffin, Ohio-portable drilling outfits and horsepower and hand power augers. 

National Supply Company, Pittsburg, Pa.-standard, hydraulic rotary, and 

portable oil-well outfits. 

Oil Well Supply Co~pany, Pittsburg, Pa.-standard, hydraulic rotary, ·canadian pole-tool, and portable oil-well outfits. 

Southern Well Works Company, Beaumont, Tex.-standard and hydraulic 

rotary outfits. 

Sullivan Machinery Company, 42 Broadway, New York City, and Railway 

Exchange Building, Chicago-diamond drills. 

American Dian~ond Drill Company, New York-diamond drills. 
INDEX. 

A. 

Page. 

Abrasive methods, nature of.. •....... _...... 33 

Absorption. See Rainfall, absorption of. 

Acknowledgments to those aiding. . . . . . . . . . . 9 

Adams, J. J. W., well auger devised by...... 26 

Alaska, oil and gas in ......... _ ........ _ . . . . . 23 

Arkansas, drilling in, cost of ............... __ 132 

Arkansas clay auger, de.,cription of.......... 90 

Artesian conditions, explanation of. ......... 15-16 

figure showing... . . . . . . . . . . . . . . . . . . . . . . . . 15 

Asia, well drilling in... . . . . . . . . . . . . . . . . . . . . . . 23-24 

Asphalt, use of, for packing... . . . . . . . . . . . . . . . 95-96 

Atlantic Coastal Plain, drilling in............ 78 

Augers, well, cost of. . . . . . . . . . . . . . . ... . . . . . . . . 133 

description of.. .......................... 88,90 

history of.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 

Auger stem, description of. .................. 39,41 

figure showing... . . . . . . . . . . . . . . . . . . . . . . . . 39 

Australian calyx drill. See Calyx drlll. 

B. 

Bacon, J. E., depth measurement by........ 126 

drilling device of..... . . . . . . . . . . . . . . . . . . . . 111 

prote<'tion of water supply by •..•..... 118-119 

Bailer. ,f:3ee Sand bailer. 

Bedding planes, water movement along..... 13 

Bibliography of subject...................... 7 

Bits, description of. ••.............. 41,64,74,76,81 

dressing of.. .....•....................... 50-51 

figures showing .•.................. 40, 77, 80~88 

wear on ...•.......................... 50-51,65 

reduction of hole due to ... , .......... 50-51 

Bits, diamond, figure showing............... 80 

Bolles, .T. N:, self-cleaning method invented 

by............................... 27 

Bore hole, deflection of. . . . . . . . . . . . . . . . . . . . 126-127 

deflection of, figure showing. . • . . . . . . . . . . 128 

measurement of. . . • . . . . . . . . . . . . . . . 127-129 

reduction in size of. . • • . . . . . . . . . . . . 50-51, 73-7 4 

See. also Wells. 

Boring, well, augers for, description of....... 26, 

39,41,88,90 

augers for, figures showing •.............. 39,88 

cost of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l 33 

description of.. .......................... 88-90 

pump for ...•..........•....•............ 88-89 

figure showing....................... 89 

Bowlders, difficulties with •.•.....•........ 107-108 

Bullock, M. C., early drilling by............. 79 

Bull wheel, description of.................... 35 

Button, Jesse, early drilling by.............. 27 

c. Page. 

Cables, adjustment of........................ _43 

character or:........ . . . . . . . . . . . . . . . . . . . . . 43-45 

friction on ......................... ·: .... 43,60 

stretch in................................ 44 

tension on............................... 48 

Calf wheel, description of .................... 35-36 

California, drilling in........................ 78 

drilling in, cost of ...................... 130-132 

oil and gas in............................ 23 

See also California method. 

California method, advantages of............ 70 

casing for. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 

perforation of. . . . . . . . . . . . . . . . . . . . . . . . 69 

cost of. ................................ 131-132 

description of ............................ 66-70 

drilling operations with .................. 68-69 

outfit for, figures showing................ 67 

rig for.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 

tools for .............................. __ . 68 

Calyx drilling, advantages and disadvantages 

of. ............................... 87-88 

cores from, extraction of. . . . . . . . . . . . . . . . . 85-85 

extraction of, figure showing............. 86 

cost of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 

description of. ........................... 85-85 

development of .......................... 84-85 

Calyx drill, figure showing.. . . . . . . . . . . . . . . . . . 80 

Casey, Ill., well deflection at ............... 126-127 

Casing, attachments for, description of. ...... 51-55 

attachments for, figure showing .......... 53,67 

costof ................................. 130-133 

cutting of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 

forms of. ................................. 52, 54 

figures s bowing. . . . . . . . . . . . . . . . . . . . . . 53 

decay of, contamination due to ......... 119-120 

flooding due to ..................... 113-114 

inv~ntion of.. ............................ 30, 52 

need for .................................. 52,90 

pulling of................................ 55 

reduction in size of.. ..................... 73-74 

sinking of .......................... 54-55,73-74 

straightening of. ......... _ ............. 105-106 

use of. . . . . . . . . . . . . . . . . . . . . . . . 25-26, 30, 52, 60, 90 

Casing cutter, description of. ............... :. 105 

figure showing ............. .'............. 106 

Cat, description of............................ 41 

figure showing ......... _ . . . . . . . . . . . . . . . . . 39 

Caverns, underground, water absorbed by.... 12 

Caving rock, remedies for ................. 64, 69,93 

Cement, use of, for packing .. _................ 95 

Chamberlin, T. C., on capacity tests ........ 121-123 

on capacity tests, figures showing ....... 122.123 

135 
136 INDEX. 

Page. 

Chicago, caving rock at ...................... 64,93 

Chilled-shot method, advantages and disadvantages of... . . . . . . . . . . . . . . . . . . . 87 

consumption in. . . . . . . . . . . . . . . . . . . . . . . . . 133 

drilling by. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86, 88 

China, well drilling in. . . . . . . . . . . . . . . . . . . . . . . 23-24 

Chopping bit, figure showing. . . . . . . . . . . . . . . . 80 

use of. . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 

Churn drills, history of ••.................... 27-28 

invention of............................. 23 

use of . • • • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 

Clay, running, difficulties due to............ 108 

Clay beds, water in .......................... 17-18 

Cleaning wells, methods of .................. 97-98 

Cleavage planes, water movement along...... 13 

Conductor box, nature and use of ............ 51-52 

Conglomerate, water in...................... 19 

Cook strainer, description of................. 99 

figure showing. . . . . . . . . . . . . . . . . . . . . . . . . . 99 

Core barrel, descriptions of .................. 83,85 

figures showing... . . . . . . . . . . . . . . . . . . . . . . . 83, 85 

Core drilling, cost of......................... 133 

description of. . . . . . . . . . . . . . . . . . . . . . . . . . . 30 

difficulties in ............................ 86-87 

methods of, comparison of ............... 87-88 

uses of. ........................... 30, 33,78-79 

See also Percussion core drill; Diamond 

drill; Chilled-shot method. 

Cost of drilling, statistics on ............... 129-133 

See also particular methods. 

Couplings, description of •..••............ 52, 54, 79 

figures showing .......................... 53,80 

Cutter bit, figure showing................... 80 

use of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 

D. 

Dallas, Tex., water supply of................ 119 

Depth, measurement of •...••............. 125-126 

Derrick, description of ...................... 34-37 

size of ...................... _ . __ . _ . _ . . . . . 36 

See also Pole-tool method; California 

method. 

Diamond drilling, advantages and disadvantages of. ..................... 87-88 

cores from, extraction of................. 83 

extraction of, figure showing. . . . . . . . 83 

cost of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 

description of. . . . . . . . . . . . . . . . . . . . . . . . . . . 79 

feed for. . . . . . . . . . . . . . . . . . .. . .. . . . . . . . . . . . 81 

invention of .......................... __ . 79 

operations in ........... __ .. __ .......... _ 84 

outfit for. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79-83 

figures showing ..................... _ 79 

Diamond drills, views of.. .............. __ .. . 78 

Diamonds, bit for ........................... 81-82 

bit for, figure showing................... 80 

cost of ............................... 84-85,133 

description of... . . . . . . . . . . . . . . . . . . . . . . . . . &2-83 

Dip, relation of, to area of outcrop............ 12 

relation of, to area of outcrop, figure showing. • . . . . . . . . . . . . . . . . . . . . . .. .. . . . 12 

Double-cone method, depth measurement by. 126 

Drift, glacial, water in....................... 18 

Drillers, opinions of, on type of rig........ . . . 58-59 

Drill hole. See Bore hole. 

Drilling, cost of.. . . • . . . . . • . . . . . . . . . . . . . . . . . 129-133 

Page. 

Drilling, difficulties in .•••...•••.•••••.••.. 102-112 

history of.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23-30 

methods of. .•.......................... 32-102 

classification of ...................... 32-33 

supply companies for, list of............. 134 

Drills, change oi, during work............... 33 

rotation of............................... 47 

See also Bits. 

Drive head, description of................... 55 

figure showing.... . . . . . . . . . .. . . . . . . . . . . . . 53 

Drive point, description of ................... 91-92 

figures showing... . . . . . . . . . . . . . . . . . . . . . . . 88 

Drive shoe, description of ................. 54-55, f~g 

figures showing.. . . . . . . . . . . . . . . . . . . . . . 53, 67, 77 

Driving, well, cost of........................ 133 

description of.. ....................... 26,91-92 

history of.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 

Dry holes, drilling in........................ 51 

flooding through......................... 114 

meaning of term.. . . . . . . . . . . . . . . . . .. . .. . . 51 

E. 

Electro-magnets, recovery of lost tools by.... 105 

Elevators for casing, figure showing......... . 53 

use of... . . . . . . . . . . . .. . . . . . . . . . . . .. . . .. .. . 55 

Expansion drills, figures showing... . . . . . . . . . 77 

Europe, well-drilling in ...................... 24-25 

Evaporation, differences in.................. 11 

F. 

Faults, water passages formed by. . . . . . . . . . . . 12-13 

Field work, extent of........................ 7-8 

Fishing. See Lost tools, recovery. 

Flaxseed, use of, for packing ............. 29,94-95 

Flooding, well cleaning by................... 98 

See also Oil wells, flooding of. 

Floor circles, description of.. . .. . . . . . . . . . . . . . 41 

figure showing.... . . . . . . . . . . . . . . . . . . . . . . . 42 

Foliation, water movement along............ 13 

Formations, oil and gas bearing, character of. 21-22 

distribution of. .......................... 22-23 

Formations, water bearing, description of. ... 17-21. 

locating of.. ........................ __ ... 16-17 

France, well drilling in. . . . . . . . . . . . . . . . . . . . . . 24-25 

Freezing,penetrationofquicksand by aid of. 111-121 

Friction, effect of, in drilling .............. 124-125 

Fuller, M. L., aid of. ..... __ ................. 9 

G. 

Gas, occurrence of. .......................... 21-23 

Gas packers, description of. . . . . . . . . . . . . . . 93-94,96 

figure showing ................... __ ,..... 53 

Glenn, L. C., on well pollution.............. 118 

Gneiss, water in............................. 20 

Granite, water in............................ 20 

Grasshopper rig, character of. . . . . . . . . . . . . . . . 29 

Gravel beds, water in....................... 17 

H. 

Hand power, use of.......................... 8 

Headache post, description of. . . . . . . . . . . . . . . 36 

Hollow-rod method. See Self-cleaning 

method. 

Horn socket, description of.................. 105 

figure showing.... . . . . . . . . . . . . . . . . . . . . . . . . 106 
INDEX. 13'7 

Page. 

Horsepower, use of.......................... 8 

Hydraulic feeds, description of. . . . . . . . . . . 42-43, 81 

Hydraulic jack, figure showing. . . . . . . . . . . . . . 53 

use of................................... 55 

Hydraulic methods, nature of ............... 32-33 

Hydraulic rotary method, advantages and 

disadvantages of................ 75 

casing for •............................... 73-74 

cost of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 

description of.. ....................... 30,70-75 

development of. ......................... 30,70 

drilling operations in .................... 71-75 

outfit for. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 

figure showing. . . . . . . . . . . . . . . . . . . . . . 72 

speed of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 

useof. ...•.............................. 30 

water for.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71, 73 

water in, loss of......................... 75 

I. 

Illinois, drilling in ........................... 59-58 

Indiana, oil and gas in. . . . . . . . . . . . . . . . . . . . . . 22 

plugging law in ....................... 116-117 

J. 

-Jars, adjustment of. . . . . . . . . . . . . . . . . . . . . . . . . . 39 

description of. ....................... 29, 38-39 

figure showing. . . . . . . . . . . . . . . . . . . . . . . . . . 39 

invention of............................. 29 

Jetting method, advantages of. .............. 76,78 

casing for. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 

cost of. . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 

description of ..................... 26-27, 32-33 

drilling methods in . . . . . . . . . . . . . . . . . . . . . 76 

history of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 

outfit for ................................ 75-76 

figure showing. . . . . . . . . . . . . . . . . . . . . . 77 

tools for. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 

figure showing. . . . . . . . . . . . . . . . . . . . . . 77 

uses of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76, 78 

Joints in rocks, water passages formed by.... 13 

Joints in wells, testing of.................... 94 

K. 

Kansas, oil and gas in ....................... 22-23 

Kaolin, mining of. . . . . . . . . . . . . . . . . . . . . . . . . . . 78 -

Koch, George, inventions by ........ ~....... 29 

L. 

Lake deposits, water in..................... 21 

Layne strainer, description of... . . . . . . . . . . . . 98 

figure showing.......................... 99 

Leschot, Rudolph, diamond drill used by.... 79 

Limestone, water in......................... 20 

Literature of subject........................ 7 

Loomis, G. D., aid of........................ 26 

Loran, -.,photographic apparatus devised 

by ... • ..•.. -.- - -...... -.. -. --. - 103-104 

Lost tools, causes for ...•...... 102-103,108,109-110 

locating of. ............................ 103-104 

recovery of. . . . . . . . . . . . . . . . . . . . . . . . . 86, 103-106 

tools for. . . . . . . . . . . . . . . . . . . . . . . . . . . 104-106 

figures showing ................. 80,106 

Louisiana, oil and gas in. . . . . . . . . . . . . . . . . . . . 23 

:M. 

Page. 

Moran, D. E., on freezing quicksand ...... 111-112 

Morris, William, jars invented by........... 29 

Mud, running, difficulties due w............ 108 

N. 

Nitroglycerin, use of, in cleaning wells ....... 97-98 

See also Torpedoes. 

0. 

Ohio,oilandgasin.......................... 22 

plugging law in.......................... 116 

Ohio machine, description of................ 65 

Oil, occurrence of... . . . . . . . . . . . . . . . . . . . . . . . . . 21-23 

Oil wells, flooding of, causes oi. ............ 112-114 

flooding of, definition of ............... 112-113 

effects of............................ 114 

laws for prevention of. . . . . . . . . . . . . . 115-117 

torpedoing of. . .. . .. . . . . . . . . . . . .. . .. . . . 100-102 

Oklahoma, oil and gas in .................... 22-23 

Outcrop, area of, relation of dip and.......... 12 

area of, relation of dip and, figure showing 12 

Outfit, meaning of term . . . . . . . . . . . . . . ... . . . . . 33 

selection of. . • . . . . . . . . . . . . . . . . . . . . . . . . . . . 33-34 

P. 

Packing, methods of. .. .. .. .. . .. .. . . . .. . .. 74, 94-96 

need for. . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93-94 

Parts, replacement of..... . . . . . . . . . . . . . . . . . . . 58 

Pennsylvania, drilling in, cost of.. ......... 129-130 

gas packing in. . . . . . . . . . . . . . . . . . . . . . . . . . . 93-94 

oil and gas in............................ 22 

plugging law in . . . . . . . . . . . . . . . . . . . • . . . . . 115 

well-drilling in...... . .. . .. . . . . . . . . . .. . .. . 25,29 

Percussion core drill, description of....... .. . 59 

figure showing... . . . . . . . . . . . . . . . . . . . . . . . . 59 

Percussion methods, nature of. .............. 32,33 

Perforator, figure showing. . . . . . . . . . . . . . . . . . . 67 

use of..... .. . . . . . . . . . . . . . . .. . . .. . .. . . . . . . 69 

Photography, use of, in recovering lost tools. 103-104 

Pipe ring, description of..................... 53 

figure showing.... . . . . . . . . . . . . . . . . . . . . . . . 55 

Pipe swedge, straightening of... . . . . . . . . . . . . . 106 

Pleasantville rig, description of.............. 29 

Plugging, laws requiring .................. , 11S.:i17 

Poetsch, F. H., artificial freezing by......... 111 

Pole-tool method, cost of. . • . . . . . . . . . . . . . . . . . 131 

derrick for.... .. . .. . . . .. .. . .. . . . .. .. . .. .. 61 

description of..... . . . . . . .. . . . . . . . . . . . . .. . 59-61 

drilling operations in. . . . . . . . . . . . . . . . . . . . 61-64 

invention of. . .. . . . . . . .. . . . . . . . . . . . . .. .. . 24 

outfit for. • • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 

figure showing..... . . . . . . . . . . . . . . . . . . 62 

tools for .••............. !". • • • • • • • • • • • • • • • 61-63 

lossof............................... 63 

Porosity, absorption and, relations of........ 12 

Portable rig, advantages and disadvantages 

of .••............................ 57-til 

construction of.. • .. .. .. .. . .. . .. .. .. .. . .. 56-57 

drilling with, cost of ................... 130-131 

practical depth of sinking with .......... 56,57 

view of... . . . . . . • . .. . . . . . . . . . . . . . . . . .. .. . 56 

weight of................................ 56 

Pumping, passage of quicksand by......... 111 

Punching, well, description of. • . • • • • . . . . . . . . 91 

Marriott, H. F., on w~U deflection ......... j .. 127 Q. 

Method of treatment, statement of. ....•. +. 

Mississippi Valley, drilling in, cost of. ...... 1 •• 

8-9 Quartzite, water in ...... ~ .... ~ ..... ."........ 19 

130 Quicksand, character of ••••••••••••••••..• 108-109 
138 INDEX •. 

Page. 

Quicksand, difficulties with •.....••. 64,69,108-112 

freezing of, method of •..•.••.......... 111-112 

pressure of.............................. 109 

R. 

Racket and jack, description of... . . . . . . . . . . . 41 

figure showing.......................... 42 

Rainfall, absorption of •...................... 11-12 

amount of............................... 9-10 

disposal of .•..•.••...................... lQ-13 

distribution of.......................... 9-10 

map showing.... . . . . . . . . . . . . . . . . . . . . 10 

Reamer, figure showing..................... 40 

Recovery taps, description of................ 86 

figures showing. . . . . . . . . . . . . . . . . . . . . . . . . 81 

·Reel brake, description of................... 35 

Rig, meaning of term. . . . . . . . . . . . . . . . . . . . . . . 33 

See also Portable rig. 

Rig for standard method, description of. .... 34-37 

Roberts, E. A. L., use of torpedoes by....... 100 

Rocks, absorption of water by ..•............ 11-12 

See also Formations. 

Rope clamp, figure showing.. . . . . . . . . . . . . . . . 40 

Rope knife, figure showing.................. 106 

Rope socket, description of. . . . . . . . . . . . . . . . . . 38 

figure showing.......................... 39 

Rope spear, description of................... 105 

figure showing. . . . . . . . . . . . . . . . . . . . . . . . . . 106 

Rubber packers, use of ................... ~.. 46 

Run-off, proportionate amount of ...... -..... 1o-11 

s. 

Saginaw, Mich., water supply at .......... 118-119 

Samson post, description of.... . . . . . . . . . . . . . . 35 

Sand beds, water in ..... _ . .. . .. . .. .. . . .. .. .. 17 

Sand bailer, description of ................... 49,69 

figure showing ..... _ ..... _ . . . . . . . . . . . . . . . 40 

Sand pump, fignre showing................. 40 

Sand reel, description of. _. __ . . . . . . . . . . . . . . . . 36 

Sands, L. C., attempt to remedy ftGoding by . 114 

Sandstone, water in ..... _................... 19 

Schist, water in .•.... __ ..................... 20 

Schistosity, water movement along. . . . . . . . . . 13 

Screens, clogging of ......................... _ 92 

cost of ................................. _. 133 

description of... . . . . . . . . . . . . . . . . . . . . . . . . . 98 

figures showing .......................... 88, 99 

use of ....................... 74-75,91-92,98-99 

Self-cleaning method, cost of. ...... _. _ . . . . . . . 131 

drilling operations in. . . . .. .. . . . . .. .. .. . . 65 

history of.. .. . .. .. .. .. .. .. .. . .. .. . .. .. .. . 27 

invention of. ... :........................ 27 

outfit for ................................ 64--65 

rotation of pipe in. • . . . . . . . .. . . . . .. . . .. . • 65 

nses&f .................................. - 66 

Shale beds, water in........................ 19 

Sh9e. See Drive shoe. 

Shooting. See Torpedoes. 

Shot. See Chilled-shot method. 

Sinker bar, description of.................... 38 

figure showing....... . . . . . . . . . . . . . . . . . . . • 39 

Slip sock~t, di.!scription of ..••............. 104-105 

figure shewing..... . . . . . . . . . .. . . . . . . . .. . • 106 

Slush pit, figure showing. • • . . . . . . . . . . . . . . . . . 72 

use of................................... 71 

Solution caverns, nature of.................. 12 

Page. 

South Africa, well deflection at •...• _ ...... _. 127 

well deflection at, figure showing........ 128 

Spalls, difficulties with .. _ ......... _ . _ . _. . . . . 107 

Spring-pole drilling outfit, description of.._ .. 27-28 

figure showing... . . . . . . . . . . . . . . . . . . . . . . . . 27 

Spudding, devices for........................ 57 

explanation of ........................... 45--47 

rig arranged for, figure showing.......... 46 

Spudding spear, figure showing.............. 106 

use of ................................ ·... 104 

Standard method, casing for ................. 51-55 

casing for. See tzlso Casing. 

character of.. .. .. .. .. .. .. .. .. .. .. .. .. .. . 34 

cost or. ................................ 129-130 

drilling operations with ................. 45-51 

engine and boiler for.. ................... 37-38 

evolution of. • . .. .. .. .. .. . .. .. .. . . .. .. .. . 28-30 

-outfit for, description of ................. 34-45 

view of.............................. 34 

tools for. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38-41 

figures showing..... . . . . . . . . . . . . . . . . . 39, 40 

string of, connections of............. 41 

figure showing.. . . . . . . . . . . . . . . . . . 39 

withdrawal of .. _... . . . . . . . . . . . . . . . . . . 4R-49 

St.eam power, use of ................... _ .... _ . 8-9 

Steel cables, advantages and disadvantages of 43-45 

Stovepipe method. See r.alifornia method. 

Strainers. See Screens. 

Stream deposits, water in.................... 21 

Structure, rock. relation of, to rain absorpt-ion 12 

Supply companies, list c;>f.................... 134 

T. 

Tape, depth measurement by ............. 125-126 

Temper screw, description of. ............... 41-43 

figure showing .......................... _ 39 

Texas, drilling in ............................ 70,75 

oil and gas in.. ... .. .. .. .. .. .. .. .. . .. .. .. 23 

screens in..... .. . .. . .. . .. . .. .. .. . . .. .. .. . 98 

Thompson, A. B., on photographic recovery 

of lost tools..... . . . . . . . . . . . . . . . . . 104 

Till beds, water in.......................... . 18 

Tools, lost. See Lost tools. 

Torpedoes, use of .......................... lOQ-102 

use of, history of.... .. .. . .. .. .. .. . .. .. . • . 100 

See also Nitroglycerin. 

Tubular wells, construction of. .............. 25-26 

u. 

Underground water, amount of. •............ 13-15 

depthof................................. 14 

See also Artesian water. 

United States, well drilling in, history of .•.. 24-30 

v. 

Veatch, A. C., on Arkansas clay auger....... 90 

on self-cleaning method... . . . . . . . . . . . . . . . 66 

on well punching........................ 91 

w. 

Walking beam, use of, in drilling ......... 29,47-'50 

Washington, drilling in, cost of.............. 131 

Water, addition of, in drilling ....•.... 49--50,65,69 

casing off of. ....... _. .. . .. . .. .. .. . .. .. .. 52 

pressure of, at well bottom.............. 54 

See also Underground water; Artesiau 

conditions. 
INDEX. 139 

Page. 

Water pressure, penetration of quicksand 

by •......................... -. 110-111 

Water swivel, description of.................. 64 

Water wells, contamination of, causes oL. 119-120 

contamination of, examples of...... . . . 117-119 

prevention of ...................... 117,120 

torpedoing of... . . . . . . . . . . . . . . . . . . . . . . . . . 102 

Watson, Jonathan, early drilling by......... 25 

Weather, protection from.................... 58 

Webber, Henry,invention by............... 29 

Well augers. Bee Augers. 

Wells, W. C., well drilling by................ 26 

. 0 

Page. 

Wells, capacity of. •.•..•.......... -~ ...... 123-124 

capacity of, tests of..... . . . . . . . . . . . . . . . 120-123 

deflection of. Bee Bore boles. 

depth of. .............................. 125-126 

drilling of. Bee Drilling. 

locating of •.............................. 16-17 

sizes of, relative advantages of........... 124 

Bee also Water wells; Oil wells; Bore holes; 

Wells, deep. 

Wells, deep, distribution of. ................. 30-31 

Wet holes, drilling in ........................ 51,93 

meaning of term................. . . . . . . . . 51 
..