Bulletin No. 339 , Series Q, Fuels, 10

DEPARTMENT OF THE INTERIOR 

UNITED STATES GEOLOGICAL SURVEY

GEORGE OTIS SMITH, DIRECTOR

THE PURCHASE OF COAL UNDER GOVERNMENT

AND COMMERCIAL SPECIFICATIONS ON THE

BASIS OF ITS HEATING VALUE

WITH ANALYSES OF COAL DELIVERED UNDER 

GOVERNMENT CONTRACTS

BY

D. T. RANDALL

WASHINGTON

GOVERNMENT PRINTING OFFICE

1908

CONTENTS.

Page.

Introduction ______ ______________ {5

Advantages of definite specifications in the purchase of coal________ G

Value of coal as a fuel_____________________________ 7

Specifications in use_ __ r_ __ _______ 10

Methods of sampling and testing______________ ______.. 21

Analyses of coals delivered to the Government________________ 24

Some publications on coal____ _ __ _ ______ 27

THE PURCHASE OF COAL UNDER GOVERNMENT AND 

COMMERCIAL SPECIFICATIONS ON THE BASIS 

OF ITS HEATING YALUE. ~

By D. T. EANDALL.

INTRODUCTION.

The people of this country have been purchasing coal for years 

on the statement of the selling agent as to its quality, or on the reputation of the mine or district from which it was obtained. The 

farmers of the country show more business judgment in the purchase 

of fertilizer than do many manufacturers in buying coal, for the 

farmer demands a chemical analysis of the fertilizer before he accepts it.

Until recently there has oeen but little reliable information regarding the character of the coal supply of the United States. This fact 

was recognized in the establishment of the fuel-testing plant of the 

United States Geological Survey at St. Louis in 1904. Extended 

general investigations have been conducted at this plant and its successors and in the field, and in addition the technologic branch of 

the Survey has been charged with the duty of analyzing and testing 

the coals used by the Government.

The Government is a large purchaser of coal, reports from the various Departments indicating that nearly $6,300,000 is expended each 

year for fuel. Some time ago the necessity for a more uniform 

standard in the purchase of coal became apparent and the plan of 

buying it on the basis of its heating value was introduced in a few 

Departments. Many of the large commercial consumers in the United 

States have been purchasing their coal on contracts of this nature for 

some time.

The present paper summarizes the information on this subject obtained by the Survey, including examples of specifications that are 

now in use and analyses of some of the coal purchased by the Government during the winter of 1906-7.
O THE PURCHASE OF COAL UNDER SPECIFICATIONS.

ADVANTAGES OF DEFINITE SPECIFICATIONS IN THE 

PURCHASE OF COAT..

Under the old plan of purchasing coal, when the consumer had 

cause or thought he had cause to find fault with the quality of the 

fuel he received, he was in many cases assured that it must be good 

because, like all the other coal sent him, it came from a mine with an 

established reputation. Such a state of affairs made it difficult to 

take advantage of the competition which usually results when a considerable number of bidders are asked to submit prices. 'The purchaser was afraid to buy from any but such dealers as he knew and 

trusted, because, although each dealer claimed that his coal was equal 

in quality to that of the others, yet if it did not prove to be satisfactory there was no standard for settlement or for cancellation of the 

contract. Many thousands of dollars' worth .of coal are bought each 

year in this manner, but the purchasers would consider it ridiculous 

if they were asked to contract for a building with no specifications 

and simply on the agreement that it should be of a certain size and 

well constructed. Neither would they buy gold, silver, or even copper and iron ores on the mere information that they were mined at 

certain localities. All products of mines are now purchased to a 

great extent on the basis of their value as shown by chemical analysis. 

This is true of coal in only a small degree, but the number of contracts made on this basis is increasing every year.

The purchase of coal on a specification is as advantageous as a 

definite understanding regarding the quality and other features of 

any other product, or of a building operation or engineering project. 

The man who buys under a specification gets what he pays for and 

pays for what he gets.

When the bidder is allowed to specify the quality of the coal he 

proposes to furnish as determined by a chemical analysis, he is placed 

on a strictly competitive basis with other bidders. Such a procedure 

broadens the field for both the bidder and the purchaser. It makes 

the bidder's proposal, when accepted, a contract that specifies an 

established standard of quality. This furnishes a basis for settling 

disputes regarding the quality of the coal delivered and the price to 

be paid if the fuel is either better or poorer than has been guaranteed. If other coal must be substituted, as often happens, there is a 

standard for settlement. If the coal is uniformly poorer than the 

standard as specified there is a basis for cancellation of the contract.

The quality of coal from a given mine may vary from time to time 

through the failure of the miners to reject impurities. Sometimes 

different beds of "coal are mined at the same time and the output is 

mixed. When there is need of further preparation, such as picking
VALUE OF COAL AS A FUEL. . /'

slate and other impurities, or jigging or washing, a great deal depends on the care iised in these processes. The mining companies are 

responsible in a large measure for variations in the grade of prepared coal. The purchase of coal under, a contract on the basis of 

quality stimulates the operator to make a better preparation of the 

coal before it is shipped to market. An example of fluctuations in 

quality is furnished by the tables on pages 24-26, which show variations in the ash and British thermal units in coal delivered to some 

of the Government Departments at Washington.

It evidently will not be satisfactory to either the buyer or the seller 

to establish a standard for the coal unless this liability to variation 

is recognized and provision made for settlement when the coal is better or poorer than the standard. Experience with any method of 

buying coal shows that it will seldom be rejected when of poor quality, because of the difficulty, delay, and cost of removing it from the 

bins. The buyer is often confronted with the alternative of burning the coal delivered or going without fuel until more can be procured. Uuless the coal is very bad it is usually expedient to use it 

and pay a smaller price. This is also more favorable to the contractor, as to remove the coal would be costly and it would not be satisfactory as fuel to any other customer.

VALUE OF COAL AS A FUEL.

The purpose of burning coal under boilers is to abstract the heat 

for use in developing power, in drying various materials, or in 

warming buildings. The most valuable coal, therefore, is that which 

gives up the most heat to the boiler for a given weight burned.

Coal is now burned for power purposes in gas producers and boiler 

furnaces. For coals and lignites high in moisture or high in ash, the 

gas producer, used in connection with a gas engine, is best adapted 

to develop power. But for the generation of steam, which can be 

used for heating as well as for power purposes, a more convenient 

method is to burn the coal in a specially constructed furnace under 

a boiler.

The aim in the purchase of coal for any power plant should be 

to obtain a fuel which will produce a horsepower for the least cost, 

all things being considered, such as the equipment, the price of coal, 

and the cost of labor and repairs. Experiments have been made 

which seem to indicate that almost any fuel may be burned with 

reaspnable efficiency in a properly designed apparatus. The recognized requirements are as follows:

A supply of fuel fed to the furnace as uniformly and continuously 

as possible.
8 THE PURCHASE OF COAL UNDER SPECIFICATIONS.

An air supply slightly in excess of the theoretical amount required 

for complete combustion.

A sufficiently high temperature to ignite the gases which are driven 

off from the fuel.

A complete mixture of these gases with the air supplied before 

they reach a cooling surface, such as the shell or tubes of a boiler.

Some of the factors which may influence the commercial results 

obtained in a boiler are .the cost of the coal, as determined by price 

and heating value; care in firing; design of the furnace and boiler 

setting, size of grate, etc.; formation of excessive amounts of clinker 

and ash; draft available; size of the coal (uniformity of size is 

desirable).

The value of a coal is indicated by the number of heat units it 

contains. This heating value is expressed in terms of British thermal 

units a (abbreviated B. t. u.) per pound of coal, and is determined by 

means of a special apparatus called a calorimeter.

When coal is mined it contains moisture to a greater or less extent. 

It is exposed to the air in shipment and may either dry out or be 

drenched by rain. The moisture in the coal delivered is w.orthless to 

the purchaser, and really costs him a considerable amount in freight 

and cartage, and in the loss of the heat' absorbed during its evaporation in the furnace. If all coal had the same proportion of moisture, 

or if the moisture in coal delivered by a given dealer was constant in 

amount, the purchaser's problem, so far as this factor is concerned, 

would be simplified. Under present conditions the. moisture is an 

important element in the valuation of a ton of coal. It is evidently 

necessary to consider the coal just as it is received in order to 

determine its value to the consumer, but chemical reports should be

made on the basis of both the " dry coal" and the " coal as received."

The dry-coal basis is convenient for comparing several coals in regard 

to the relation of each element to the others; this is important because 

the moisture in the same coal varies from day to day. The dry-coal 

basis is also convenient for comparing the performance of boilers 

when burning the same or similar coals. Of several coals- having a 

similar composition, ^he one which has the least moisture and the 

least ash will generate the most steam when burned under a boiler.

Ash is«made up of earthy matter and other impurities which will 

riot burn. In commercial coals its proportion may range from 4 to 

25 per cent. Coals containing small percentages of ash are most 

valuable, not only because of their correspondingly higher heating capacity, but because there is less resistance to the free and uniform 

distribution of air through the bed of coal. The labor and cost of 

managing the fires and of handling the ashes are also correspondingly

a The British thermal unit is the amount of heat required to raise the temperature of 

1 pound of water 1° Fahrenheit.
VALUE OF COAL AS A FUEL. 9

less and are items to be considered in the choice of a coal. . With the 

ordinary furnace equipment there may be a considerable loss of efficiency and capacity through a large percentage of ash. It has been 

found that with some kinds of equipment, as the ash increases there is 

a decided drop in both efficiency and capacity. In some experiments 

made to determine the influence of excessive amounts of ash, coal 

containing as high as 40 per cent would generate no steam when fired 

on a chain grate, and therefore the efficiency and capacity of the plant 

would be zero.a Such coal would not only be worthless, but involve 

a direct expense, due to the cost of handling it. Whether the result 

would be similar with equipment other than a chain grate has not 

yet been determined. However, coals so high in ash that they are 

unsuited to boiler furnaces can be utilized in gas producers.

The volatile part of coal as shown by the analysis may in some 

coals be all combustible, but it generally contains some inert matter. 

This varies in different coal deposits and makes it impossible to determine the heating value of the coal from the proximate analysis alone. 

Moreover, not all coals having the same proportion of volatile matter 

behave alike in the furnace. It is important to know both the chemical composition and the British thermal units in order to determine 

the value of one coal as compared with another for the same purpose.

Of two. coals of'"different character, the one which contains the 

higher proportion of fixed carbon is most easily burned so as to 

give the maximum efficiency. However, if the coal containing the 

higher volatile matter is properly burned in a suitably designed 

furnace, it may be made equally efficient.

Sulphur may be present in the free state, or, as is more commonly the 

case, in combination with iron or other elements. Other impurities 

with sulphur often form a clinker which shuts out the air and increases the labor of handling the furnaces. It is possible, however, 

to burn coals containing up to 5 per cent of sulphur without particular difficulty from clinkers. A little steam introduced under the 

grate will relieve much of the trouble. Clinker may be due to other 

causes than sulphur, as any constituents of the ash which are easily 

fusible may produce it. There is need of further investigation to 

determine the influence of sulphur and the elements which comprise the ash on furnace fires and combustion.

The size of the coal influences the capacity of any given equipment, owing to its effect on the draft. With a poor draft fine coal 

can not be. burned in sufficient quantities to maintain the rated capacity. If thin fires are resorted to, the efficiency is usually lowered as a 

result of an excessive supply of air through holes in the fire. As a

0 Abbott, W. L., Some characteristics of coal as affecting performance with steam 

boilers, a paper read before the Western Society of Engineers, Chicago, 111.

24673 Bull. 339 08 2
10 THE PUECHASE OF COAL UNDER SPECIFICATIONS.

rule, when dust and very fine coal are fed into the furnace they 

either check the flow of air or are taken up by the draft and after 

being only partly burned are deposited back of the bridge wall or 

pass up the stack, to the annoyance of the people in the vicinity of 

the plant. If this dust is completely burned in passing through the 

furnace there is of course no loss of fuel. It has been found that coal 

of a uniform size is most satisfactory, as it does not pack so closely 

as a mixture of sizes. .

In general it may be said that in any market the coal obtainable at 

the lowest price is the most economical, provided the furnace equipment is suitable. If the furnace is not so designed as to permit the use 

of the cheaper coal, it should be changed.

The results of tests tend to show that, other conditions being equal, 

coals of similar composition are of value in proportion to the British 

thermal units in the coal as received a basis on which, indeed, all 

coals may be valued approximately. It should be remembered, however, that the value of a coal for any particular plant is influenced by 

the fact that all furnaces are not equally suitable for burning the many 

grades of coal. Aside from this factor, coals may be compared in 

terms of the British thermal units obtained for 1 cent, or on the cost 

per million heat units.

In the purchase of coal, then, attention should be given to the 

character of the furnace equipment and the load; the character 

of coal best suited to the plant conditions; the number of heat units 

obtainable for a unit price; the cost of handling the coal and ash; 

and the possibility of burning.the coal without smoke or other objectionable features.

SPECIFICATIONS IN USE.

As the result of a letter from President Koosevelt to the national

advisory board on fuels and structural materials, calling attention to 

the need of a uniform and efficient basis for the purchase of the Government fuel supply, the following specification was drafted by engineers in the employ of the Government and approved by this board in 

March, 1907:

SPECIFICATIONS AND PROPOSALS FOB SUPPLYING COAL.

United States ____________

_________ ____, 190__

PROPOSAL.

Sealed proposals will be received at this office until 2 o'clock p. m., ____, 

190__, for supplying coal to the United States _____________ building 

.at _..__________ as follows:
SPECIFICATIONS IN USE. 11

The quantity of coal stated above is based upon the previous annual con-: 

sumption, and proposals must be made upon the basis of a delivery of 10 per 

cent more or less than this amount, subject to the actual requirements of the 

service.

Proposals must be made on this form, and include all expenses incident to 

the delivery and stowage of the coal, which must be delivered in such quantities 

and at such times within the fiscal year ending June 30, 190_, as may be 

required.

Proposals must be accompanied by a deposit (certified check, when practicable, in favor of _____________) amounting to 10 per cent of the aggregate amount of the bid submitted, as a guaranty that it is bona fide. Deposits 

will be returned to unsuccessful bidders immediately after award has been 

made, but the deposit of the successful bidder will be retained until after the 

coal shall have been delivered and final'settlement made therefor, as security 

for the faithful performance of the terms of the contract, with the understanding that the whole or a part thereof may be used to liquidate the value of any 

deficiencies in quality or delivery that may arise under the terms of the contract.

When the amount of the contract exceeds $10,000, a bond may be executed in 

the sum of 25 per cent of the contract amount, and in this case the deposit or 

certified check submitted with the proposal will be returned after approval of 

the bond.

The bids will be opened in the presence of the bidders, their representatives, 

or such of them as may attend, at the time and place above specified.

In determining the award of the contract, consideration will be given to the 

quality of the coal offered by the bidder, as well as the price per ton, and 

should it appear to be to the best interests of the Government to award the 

contract for supplying coal at a price higher than that named in lower bid or 

bids received, the award will be so made.

The right to reject any or all bids and to waive defects is expressly reserved 

by the Government.

DESCRIPTION OF COAL DESIRED.*

Bids are desired on coal described as follows:

Coals containing more than the following percentages, based upon dry coal, 

will not be considered:

Ash _____ ____ _ _____________ __per cent. 

Arolatile matter ____________ ______ __per cent. 

Sulphur ___________________________ __per cent. 

Dust and fine coal as delivered at point of consumption B _________________________ __per cent

DELIVERY.

The coal shall be delivered in such quantities and at such times as the Government may direct.

0 This information will be given by the Government as may be determined by boiler 

and furnace equipment, operating conditions, and the local market. 

6 All coal which will pass through a i-inch round-hole screen.
12 THE PURCHASE OF COAL UNDER SPECIFICATIONS.

In this connection it may be stated that all the available storage capacity of 

the coal bunkers will be placed at the disposal of the contractor to facilitate 

delivery of coal under favorable conditions.

After verbal or written notice has been given to deliver coal under this contract,-a further notice may be served in writing upon'the contractor to make 

delivery of the coal so ordered within twenty-four hours after receipt of said 

second notice.

Should the contractor, for any reason, fail to comply with the second request, 

the Government will be at liberty to buy coal in the open market, and to charge 

against the contractor any excess in price of coal so purchased over the contract 

price.

SAMPLING.

Samples of the coal delivered will be taken by a representative of the Government.

In all cases where it is practicable, the coal will be sampled at the time it is 

being delivered to the building. In case of small deliveries, it may be necessary 

to take these samples from the yards or bins. The sample taken will in no case 

be less than the total of 100 pounds, to be selected proportionally from the 

lumps and fine coal, in order that it will in every respect truly represent the 

quantity of coal under consideration.

In order to minimize the loss in the original moisture content the gross sample will be pulverized as rapidly as possible until none of the fragments exceed 

one-half inch in diameter. The fine coal will then be mixed thoroughly, and 

divided into four equal parts. Opposite quarters will be thrown out, and the 

remaining portions thoroughly mixed and again quartered, throwing; out opposite quarters as before. This process will be continued as rapidly as possible 

until the final sample is reduced to such amount that all of the final sample 

thus obtained will be contained in the shipping can or jar and sealed air-tight.

The sample will then be forwarded to______________________________

If desired by the coal contractor, permission will be given to him, or his representative, to be present and witness the quartering and preparation of the 

final sample to be forwarded to the Government laboratories.

Immediately on receipt of the sample, it will be analyzed and tested by the 

Government, following the method adopted by the American Chemical Society, 

and using a bomb calorimeter. A copy of the result will be mailed to the contractor upon the completion thereof. "

CAUSES FOR REJECTION.

A contract entered into under the terms of this specification shall not be 

binding if, as the result of a practical service test of reasonable duration, the 

coal fails .to give satisfactory results owing to excessive clinkeriug or to a prohibitive amount of smoke.

It is understood that the coal delivered during the year will be of the same 

character as that specified by. the contractor. It should, therefore, be supplied, 

as nearly as possible, from the same mine or group of mines.

Coal containing percentages of volatile matter, sulphur, and dust higher than 

the limits indicated on page 2 and coal containing a percentage of ash in excess 

of the maximum limits indicated in the following table will be subject to rejection.

In the case of coal which has been delivered and used for trial, or which has 

been consumed or remains on the premises at the time of the determination of
SPECIFICATIONS IN USE. 13

its quality, payment will be made therefor at a reduced price, computed under 

the terms of this specification.

Occasional deliveries containing ash up to the percentage indicated in the 

column of " Maximum limits for ash," on page 4, may be accepted. Frequent 

or continued failure to maintain the standard established by the contractor, 

however, will be considered sufficient cause for cancellation of the contract.

PRICE AND PAYMENT.*1

Payment will be made on the basis of the price named in the proposal for 

the coal specified therein, corrected for variations in heating value and ash, 

as shown by analysis, above and below the standard established by contractor 

in this proposal. For example, if the coal contains 2 per cent, more or less, 

British thermal units than the established standard, the price will be increased 

or decreased 2 per cent accordingly.

The price will also be further corrected for the percentages of ash. For all 

coal which by analysis contains less ash than that established in this proposal 

a premium of 1 cent per ton for each whole per cent less ash will be paid.

An increase in the ash content of 2 per cent over the standard established by 

contractor will be tolerated without exacting a penalty for the excess of ash. 

When such1 excess exceeds 2 per cent above the standard established, deductions will be made from price paid per ton in accordance with following table:

Ash as established in 

proposal (per cent).

K

7 ___ . _ 

9 __ . _ . _. _

10 ___ ... _____ _ -

11. _______ - _ 

12 ________________ .

13 __ _ . _ . .............

14 ___ .... _ - ____ ..

15

16 _____ - _____ . __ ....

17 _______________ .

18 __ - _ __ - - -

No deduction 

for lim- its below.

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20

Cents per ton to be deducted.

2 '

4 7 12 18 25 35

Percentages of ash in dry coal.

7- 8 

8-9 

9-10 

10-11 

11-12 

12-13 

13-14 

14-15 

15-16 

16-17 

17-18

18-19 

, 19-20 

20-21

8- 9 

9-10 

10-11 

11-12 

12-13 

13-14

14-15 

15-16 

10-17 

17-18 

18-19 

19-20 

20-21 

21-22

9-10 

10-11 

11-12 

12-13 

13-14 

14-15 

15-16 

16-17 

17-18

18-19

19-20 

20-21 

21-22 

22 23

10-11 

11-12 

12-13 

13-14

14-15 

15-16

16-17 

17-18

18-19 

19-20 

20-21 

21-22 

22-23

11-12

12-13 

13-14

14-15

15-16 

16-17 

17-18 

38-19 

19-20 

20-21 

21-22

22-23

12.13- 

13-14 

14-15 

.15-16 

16-17 

17-18 

18-19 

19-20 

riO-21 

21-22

13-14 

14-15 

15-16 

16-17- 

17-18

Maximum 

limits 

for 

ash.

. 12 

13 

14 

14 

15 

16 

16 

17 

18 

19 

19 

20 

21 

22

Proposals to receive consideration must be submitted upon this form and 

contain all of the information requested.

.1.90.

The undersigned hereby agree to furnish to the U. S _ . 

building-at _____________, the coal described, in tons, of 2,240 pounds

0 The economic value of a fuel is affected by the actual amount of combustible matter it contains, as determined by its heating value shown in British thermal units per pound of fuel, and 

also by other factors, among which is its ash content. The ash content not only lowers the 

heating value and decreases the capacity of the furnace, but also materially increases the cost of 

handling the coal, the labor of firing, and the cost of the removal of ashes, etc.
THE PURCHASE OF COAL UNDER SPECIFICATIONS.

each and in quantity 10 per cent more or less than that stated on page 1, as 

may be required during the fiscal year ending June 30, 190_, in strict accordance with this specification; the coal to be delivered in such quantities and at 

such times as the Government may direct.

Description.

Name of mine __ _____ ___ __

Location of mine. . ___ _ ____ -

Size of coal (if coal is screened) :

Coal to pass over openings ______ - 

Data to establish a basis for payment .

American Chemical Society).

Item No ....

>square. 

..-inchesjbar.

Item No. _

>square. 

_ inchesjbar.

Item No. .

>square. 

_ inchesjbar.

It is important that the above information does not establish a higher standard than 

can be actually maintained under the terms of the contract; and in this connection it 

should be noted that the small samples taken from the mine are invariably of higher 

quality than the coal actually delivered therefrom. It is evident, therefore, that it will 

be to the best interests of the contractor to furnish a correct description with average 

values of the coal offered, as a failure to maintain the standard established by contractor 

will result in deductions from the contract price, and may cause a cancellation of the contract, while deliveries of a coal of higher grade than quoted will be paid for at an increased price.

Signature____________________

Address____________________

Name of corporation_______ _ _ _ 

Nanse of president________ _ 

Name of secretary.__ _______________

Under what law (State) corporation is organized__________________

As will be seen from the foregoing specification, the bidder is not 

required to submit a sample of his coal, but is expected to name a 

standard of British thermal units in the coal as it is to be delivered. 

This value is made the basis for purchase, because a correction is thus 

made for the amount of moisture in the coal... It should be noted that 

this value will in all cases be lower than the British thermal units in 

the dry coal, which is usually given in connection with the coal analysis. The percentage of ash is also specified, as it is a factor in the 

successful burning of the coal on the grate and as it involves an expense for removal from the premises.

If the dealer is not fairly familiar with the vv alue of his coal, it 

may then be arranged to have him submit a properly selected sample 

with his bid, this sample to be analyzed by the Government and the 

results used as a standard in the contract. It is preferred, however, 

that the bidder use his own values.

The following circular letter was issued by the Treasury Department in connection with the Government specification, for the information of dealers desiring to bid on coals for public buildings, such
SPECIFICATIONS IN USE. 15

as mints, custom-houses, and post-offices located in all parts of the 

United States:

TREASURY DEPARTMENT, OFFICE OF THE SECRETARY,

Washington, March 27,-1901.

SIR: The accompanying specifications for coal are intended to give a clear 

description of the coal desired by the Government, and to secure a definite statement of the quality of coal offered by the bidder, with a view to using such 

statement as a basis for payment in connection with the stated price per ton. 

The plan is not new in its essential .features, a~s it is an extension of a system 

already in force in the larger United States public buildings, and is similar to 

that employed by a number of private consumers.

What is desired is not necessarily the cheapest or the highest grade of coal 

per se, but the coal which will insure the greatest net economy in plant operation. In view of these facts the description of the coal inserted by the Government on page 2 of the accompanying specifications will receive careful consideration as the boiler and furnace conditions require. It is not expected that all 

deliveries will be absolutely uniform or agree exactly with the standard established by the contractor, but it is necessary that all deliveries-shall be within 

the limits set by the Government.

The.limits are wide enough to permit the use of the output of any mine or 

group of mines provided proper care is exercised in mining and picking out 

slate, bone, etc. With these points in mind it is only necessary for the bidder to 

select coal for each proposal which will meet the description given and permit 

deliveries within the limits set. The standard established by the contractor 

should be such as to require the least correction applying to deliveries for 

variation in heat units and ash from values established.

It is believed that the enforcement of the provisions of the specifications will 

operate equitably both with respect to the Government and to the contractor, 

and will guarantee adequate protection to each. Many coal dealers have already 

signified their' willingness to furnish coal on this basis, and have commended as 

well as indorsed the method.

The application of this system will not only enable the award of a contract to 

be made in an equitable manner, but will also remove many of the usual causes 

for dispute as to the character and quality of the coal subsequently delivered, 

and provide a satisfactory basis for the correction of payments for differences 

in quality in favor of the party in whose interest it is due.

The system of sampling, analyzing, and testing coal delivered under the 

Government contracts will be under the supervision of the fuel-testing division 

of the Geological Survey, in order to insure reliability and impartiality.

The heating value expressed in British thermal units of coal containing 

approximately the same percentage of ash is essentially a direct measure of the 

actual value to the purchaser, and for this reason the specifications provide for 

an adjustment of payment in direct proportion to the variation in heat units 

in the coal as received. As the coal is weighed when delivered and the .payments are based a]so upon the- price per ton, it is necessary to determine the 

heating value of the coal in the condition in which it is received, containing 

whatever moisture may be present at the time.

A further correction in payment will be made for variation of the ash in dry 

coal in order to take account of the cost of handling additional fuel and ash and 

its effect on the capacity of the boiler and furnace.

Respectfully, A. F. STATTER,

Assistant Secretary.
16 THE PURCHASE OF COAL UNDER SPECIFICATIONS.

On account of lack of information among the dealers in anthracite 

coal as to the heating value of the several sizes and kinds used by the 

Government, a number of contracts were let on the basis of the ash 

in dry coal. For the city of Washington these were worded in the 

same way as the regular specification, except the section relating to 

price and payment, which was as follows:

PRICE AND PAYMENT.

Payment will be made on the basis of the price named in the proposal for the 

coal specified, corrected for variations in ash as shown by analysis, above and 

below the standard established by the contractor.

For an increase or decrease up to 2 per cent in the ash content above or below the standard no correction will be made in the price. When the variation 

exceeds this allowance above or below the standard, corrections will be made in 

the price as follows:

For furnace, egg, stove, and chestnut sizes of coal, variations from the standard percentage of ash exceeding 2 and less than 2.5 above and below will result 

in the deduction or addition of 15 cents per ton. For each additional one-half of 

1 per cent, or fraction thereof, 3 cents more per ton will be deducted or added.

For pea coal, variations from the standard percentage of ash exceeding 2 and 

less than 2.5 above and below will result in the deduction or addition of 10 

cents per ton. For each additional one-half of 1 per cent, or fraction thereof, 2£ 

cents more per ton will be deducted or added.

For buckwheat and screenings, variations from the standard percentage of 

ash exceeding'2 and less than 2.5 above and below will result in the deduction 

or addition of 8 cents per ton. For each additional one-half of 1 per cent, or 

fraction thereof, 2 cents more per ton will be deducted or added.

The following specification is used by a few firms in Baltimore, 

Md.:

SPECIFICATIONS AND INFORMATION CONCERNING SUPPLY OF COAL FOR ____________

Caution. Bidders are directed to familiarize themselves with the storage 

facilities and local conditions, affecting the deliveries of coal, existing at the 

power house.

Method of determining quantity and quality. Weights are subject to check 

either by measurement or by company scales. Any deficiency will be deducted 

from and any excess added to the bill.

Sampling will be done by a representative of the company and contractor 

may have a representative present.

Sample will be taken from each delivery and kept in hermetically sealed jars.

Detail of specifications. Coal will be semibituminous and run-of-mine. It 

shall be dry, well picked, and free from excessive amounts of slate, pyrites, and 

dirt, of any kind and shall have the following composition: Moisture, not over 1 

per cent; volatile carbon, not over 20 per cent; ash, not over 7 per cent; sulphur, 

not over 1 per cent.

ADJUSTMENTS.

Additions. If the coal has less than 1 per cent moisture, the deficit per cent 

less than 1 per cent will be added to the bill. If the coal has less than 20 per 

cent volatile carbon, the deficit per cent less than 20 oer cent will be multiplied by 2 and added to the bill. If the coal has less than 7 per cent ash, the 

deficit per cent less than 7 per cent will be multiplied by 3 and added to the bill.
SPECIFICATIONS USE. ' 17

Deductions. If the coal contains more than 1 per cent moisture, the excess 

per cent above 1 per cent will be deducted from the bill. If the coal contains 

more than 20 per cent volatile carbon, the excess per cent above 20 per cent 

will be multiplied by 2 and deducted from the bill. If the coal contains more 

than 7 per cent ash, the excess per cent above 7 per cent will be multiplied by 3 

and deducted from the bill.

The following are the essential features of the contracts on which 

a Chicago company is said to purchase and inspect nearly 1,000,000 

tons of coal for its clients in Chicago, Indianapolis, Minneapolis, St. 

Louis, and other cities:

I. The company agrees to furnish and deliver to the consumer ______

. _____ at such times and in such quantities as ordered by the consumer for 

consumption at sr'J premises during the term hereof, .at the consumer's option, 

either or all of the kinds of coal described below; said coals to average the 

following assays:

Of size passing through screen having circular perforaOf size passing over a screen having circular perforations

__ inches

inches inches

Coal of the above respective descriptions and specified assays (not average 

assays) to be hereinafter known as the contract grade of the -respective kinds.

II. The consumer agrees to purchase from the company all the coal required for consumption at said premises during the term of said contract, 

except as set forth in Paragraph III below, and to pay the company for each 

ton of 2,000 pounds avoirdupois of coal delivered and accepted in accordance 

with all the terms of this contract at the following contract rate per ton for 

coal of each respective contract grade, at which rates the company will deliver 

the following respective numbers of British thermal units for 1 cent, the contract guaranty:

Kind of coal.

Contract 

rate per 

ton.

%

$ __

Contract guaranty.

Said net British thermal units for 1 cent being in each case determined as 

follows: Multiply the number of British thermal units per pound of dry coal 

by the per cent of moisture (expressed in decimals), subtract the product so 

found from the number of British thermal units per pound of dry coal, multiply the remainder by 2,000, and divide this product by the contract rate per 

ton (expressed in cents) plus one-half of the ash percentage (expressed as 

cents).

III. It is provided that the consumer may purchase for consumption at said 

premises coal other than herein contracted for, for test purposes, it being un-
18 THE PURCHASE OF COAL UNDER SPECIFICATION'S.

derstood that the total of such coal so purchased shall not' exceed 5 per cent of 

the total consumption during the term of this contract.

IV. It is understood that the company may deliver coal hereunder containing 

as high as 3 per cent more ash and as high as 3 per cent more moisture and as 

low as 500 fewer British thermal units per pound dry than specified above for 

contract grades.

V. Should any coal delivered hereunder contain more than the per cent of 

ash or moisture or fewer than the number of British thermal units per pound 

dry allowed under Paragraph IV hereof, the consumer may, at its option, 

either accept or reject same.

VI. All coal accepted hereunder shall be paid for monthly at a price per 

ton determined by taking the average of the delivered values obtained from the 

analyses of all the samples taken during that month, said delivered value 

in each case being obtained as follows: Multiply the number of British thermal units delivered per pound of dry coal by the per cent of moisture delivered 

(expressed in decimals), subtract the product so found from the number of 

British thermal units delivered per pound of dry coal, multiply the remainder 

by 2,000, divide this product by the contract guaranty, and from this quotient 

(expressed as dollars and cents) subtract one-half of the ash percentage delivered (expressed as cents).

In Cleveland, Ohio, coal is purchased for the waterworks on the 

basis of its heating value. The standard agreed upon is 13,624 British thermal units and was established as the result of analysis and 

tests made on a sample furnished'by the dealer.

The following are the essential features of the specifications used 

by the Interborough Rapid Transit Company of New York in purchasing about 30,000 tons of coal each month for use in its plants, 

which are among the largest in the United States:

PRELIMINARY SPECIFICATIONS FOR BITUMINOUS COAL FOR THE INTERBOROUGH 

RAPID TRANSIT COMPANY.

Coal must be a good steam, caking, run-of-mine, bituminous coal free from 

all dirt and excessive dust, a dry sample of which will approximate the company's standard in heat Aralue and analysis, as follows: Carbon, 71; volatile 

matter, 20; ash, 9; British thermal units, 14,100; sulphur, 1.50.

A small quantity of coal will be taken from each weighing hopper just before 

the hopper is dumped while the lighter is being unloaded. These quantities 

will be thrown into a receptacle provided for the purpose, and when the lighter 

is empty the contents of the receptacle will be thoroughly mixed, and a sample of this mixture will be taken for chemical analysis. This average sample 

of coal will be labeled and held for one week after the unloading of the lighter. 

The sample taken from the mixture for test will be analyzed as soon as possible after being taken. No- other sample will be recognized.

Tests of sample taken from average sample will be made by the company's 

chemist, under the supervision of the superintendent. Should the contractor 

question the results of the company's test (a copy of which will be mailed to 

him), the company will, if requested by the contractor within three days after 

copy of test has been mailed to him, forward sufficient quantity of the average 

sample taken from each weighing hopper to any laboratory in the city of New 

York which may be agreed upon by the superintendent and the contractor, and 

have said sample analyzed by it, and the results obtained from this second test 

will be considered as final and conclusive. In case the disputed values, as ob-
SPECIFICATIONS IN USE. 19

tained In the company's test, shall be found by the second test to be 2 per cent 

or less in error, then the cost of said second test shall be borne by the contractor ; but if the disputed values shall be fouucl to be more than 2 per cent 

in error, then the cost of said second test shall be borne by the company.

Should there be no question raised by the contractor within the three days 

specified, as to the values of the first analysis, the average sample of coal will 

be destroyed at the end of seven days from date of discharge of coal from 

lighter. Should a second test be made of coal taken from any lighter as herein 

provided, then any penalties to be made as set forth in paragraph under 

" Penalties " will be based on the results as obtained from the second test.

The price to be paid by the company per ton per lighter of coal will be based 

on a table of heat values for excess or deficiency of its standard, but subject 

to deductions as given in the section under " Penalized coal," including excess 

of ash, volatile matter, sulphur, or dust, or less than the minimum amount required to be contained in any lighter, for coal which shows* results less than 

the company's standard.

' Premiums or deductions are based on a rate of l.cent per ton for a

variation of 50 British thermal units per pound of coal, as indicated 

in a table a few items of which are given below:

Table for 13. t. u. values.

For coal in any lighter which is found by test to contain, per pound of dry 

coal, from 

15,501 and above____________ 28 cents per ton above standard.

15,101 to 15,150, both inclusive_______20 cents per ton above standard.

14,601 to 14,650, both inclusive 10 cents per ton above staudard.

14,101 to 14,150, both inclusive_______.Standard.

13,601 to 13,650, both inclusive___ .10 cents per ton below standard.

13,101 to 13,150, both inclusive______.20 cents per ton below standard.

12,101 to 12,150, both inclusive______.40 cents per ton below standard. 

No lighter of coal will be accepted which, by trial, in the judgment of the 

superintendent, contains an excessive amount of dry coal dust. The decision of 

the superintendent will be final in this respect. Coal taken from such lighter 

for trial will be subject to the special deduction set forth under " Penalized 

coal," but paid for in all other respects as herein provided.

Coal which is shown by analysis to contain less than 20 per cent of volatile 

'matter, 9 per cent of ash, or 1.50 per cent of sulphur, will be accepted without 

a deduction from the bidder's price, plus or minus an amount for excess of 

deficiency of British thermal unit value, as herein provided. Where the 

analysis gives amounts for any or all elements in excess of these' quantities, 

deductions will be made from the bidder's price in accordance with the tables 

of values of volatile matter, ash, and sulphur below given, plus or minus the 

amount for excess or deficiency of the standard British thermal unit value, in ' 

addition to any other deductions which may be made as herein provided.

Table of deductions for volatile matter..

For coal in any lighter which is found by test to contain, per pound of dry 

coal 

Over 

*******

20 per cent and less than 21 per cent__________ 2 cents per ton.

Over 

*******

22.5 per cent and less than 23 per cent_________12 cents per ton.

24 per cent and over_______________________18 cents per ton.
20 THE PURCHASE OF COAL U^DER SPECIFICATIONS.

This table is made for a difference of each one-half of 1 per cent and the 

deductions are at the rate of 4 cents for each 1 per cent of volatile matter.

Table of deductions for ash.

For coal in any lighter which is found by test to contain, per pound of dry 

coal 

Over 9 per cent and less than 9.5 per cent__________ 2 cents per ton.

* * * * * * *

Over 11.5 per cent and less than 12______________12 cents .per ton.

* * * * * * *

13.5 per cent and over_-______________________________23 cents per ton.

This table is made for each difference of one-half of 1 per cent and at the 

rate of 4 cents for each 1 per cent increase in the ash.

Table of deductions for sulphur.

For coal in any lighter which is found by test to contain, per pound of dry 

coal 

Over 1.50 per cent and less than 1.75 per cent________ 6 cents per ton. 

H< * . * * * * *~

Over 2 per cent and less than 2.25 per cent______ 10 cents per ton.

* * * * * * *

2.50 and over_________________________-__ 20 cents per ton.

This table is made out for each difference of one-fourth of 1 per cent and at 

a diminishing rate.

Should any lighter of coal delivered at the company's docks contain less than 

700 tons, a deduction of 7 cents per ton will be made from the price as determined by the British thermal unit value and analysis, in addition to any other 

penalty provided for herein. Should any lighter of coal delivered at the company's docks be rejected by the superintendent on account of excessive amount 

of coal dust, then a deduction of 25 cents per ton will be made from the price 

as determined by the British thermal unit value and analysis, for the coal 

taken from said lighter, in addition to any other penalty which may be made 

as herein provided. Should any lighter of coal be delivered in other than selftrimming lighters as herein provided, a deduction of 7 cents per ton will be. 

made from the price as determined by the British thermal unit value and analysis, exclusive of any other penalty which may be made as herein provided.

The contractor's bill of lading will be 'checked by the company's scales. 

Should there be a deficiency of 1 per cent or more between the bill of lading 

and the company's weights, then the company's weights will be taken as 

correct.

When the contractor has been notified by the company to deliver coal under 

this contract, a further'notice may be given requiring the contractor to make 

delivery of the coal so ordered .within twelve hours after the receipt of said 

second notice. Should the contractor, for any reason, fail to deliver the coal 

so ordered within twelve hours after the receipt of said second notice and in 

accordance with the requirements therein as to place of delivery, the company 

shall be at liberty to buy coal in the open market, and the contractor will make 

good to the company any difference there may be between the price paid by 

the company for said coal in open market and the price the company would 

have paid to the contractor had the coal been delivered by it in accordance with
METHODS OF SAMPLING AND TESTING. 21

the requirements of said notices from the company, or said difference may be 

deducted from any money then due or thereafter to become due to the contractor under the contract to be entered into.

METHODS OF SAMPLING AND TESTING.

In connection.with the Survey's study of the coal deposits of the 

country and the best methods to prevent waste in mining and utilizing the coal supply, trained inspectors have visited nearly 300 mines 

in 23 States, taking two or more samples from each mine. A study 

of the analyses of these samples and of samples taken from cars 

shipped from 175 of the same mines shows that the mine sample 

is in most instances better than the average of the coal as shipped in 

cars. On the average the coal delivered contains about one-third 

more ash than the mine sample taken in accordance with the instructions to the miners regarding the rejection of slate and impurities. 

This difference is due to the failure of the miners to follow these 

instructions in getting out coal for shipment. The samples collected 

by the Government inspectors from the mines almost invariably show 

a higher moisture content than is usually obtained in commercial sampling, because of the precaution taken to have the sample represent 

the coal in the mine.0

Mine samples when properly taken indicate the general character 

of the coal and enable one to judge of its probable value for any definite purpose.

Samples taken from the cars should.not be limited to a few shovelfuls of coal from the top of the car, because the heavier pieces gradually work down toward the bottom. Some samples taken at the 

bottom of a car have shown as much as 8 per cent more ash than 

the coal at the top. The moisture also may vary from top to bottom, depending on the weather. The only way to get a fair sample 

is to take a number of shovelfuls of coal from various points in the 

car, .so as to procure a representative portion of the coal from top to 

bottom arid from end to end.

Bituminous coal when exposed to the air gradually depreciates in 

heating value, owing to losses of volatile matter, but aside from this 

loss there should be the same total number of heat units in a car of 

coal when it reaches its destination as when it started. If rain falls 

on the coal it will become heavier and a greater number of pounds 

will be delivered, but each pound will have a correspondingly lower 

heat Arable. On the other hand, if the weather is fair and the coal 

dries out on the way, it will weigh less and the heating value of 

each pound-will be correspondingly higher. In other words, under 

a specification such as is used by the Government, neither the dealer

«A description of the method of mine sampling is given in Bull. U. S. Geol. Survey 

No. 290, 1906, pp. 17-18. See also Bull. No. 316, 1907, pp. 486-517.
22 THE PURCHASE OF COAL UNDER SPECIFICATIONS.

nor the purchaser will gain or lose by change in the moisture content of the coal between the time it is weighed at the mine and the 

time it is weighed on delivery. The price per ton will be correspondingly lower if the coal is wet and higher if the coal is dry.

In order to determine the maximum variation in moisture in several sizes of anthracite coal the following experiments were made: 

The coal was soaked in water to allow it to absorb as much moisture 

as possible, the result representing the extreme conditions due to 

rains or other causes. Each sample was then weighed and allowed 

to dry in a room exposed to the air. When this sample ceased to lose 

moisture it was assumed to be air dried, which represents the condition of least moisture to be expected in a delivery of coal. The results are summarized in the f6llowing table:

Experiments to determine possible variations 'of moisture in anthracite coal

during shipment.

Total moisture in thoroughly wet coaL __ 

Percentage of maximum variation in moisture

_ per cent.. 

_______ do _ -

 . do -

from wet to airFurnace.

13

0.5 to 24

5.12 

3.58

.73tol.54

30

Pea.

10

24

5.74 

1.84

3.1to3.9

68

Buckwheat.

12

24

8.44 

2.24

4.5to6.2

74

The air-dried anthracite still contains, from 1.8 to 3.6 per cent of 

moisture. Moisture in air-dried coal varies with the weather, just as 

it does in wood.

The moisture in air-dried bituminous co'als depends on the character 

of the coal. It is about 1 per cent in West Virginia coal and about 7 

per cent in Illinois coal. The moisture in the same Illinois coal

delivered may range from 7 to 1Y per cent.

Owing to these variations some method should be used to correct 

for the difference in moisture in coals of different character.

The following suggestions are presented for the guidance of those 

who wish to send samples to a laboratory for analysis:

If samples are taken at the buildings as the coal is delivered, it will 

usually be satisfactory to take one shovelful of coal from each third 

or fifth wagonload, the load being selected without the knowledge of 

the driver. It must be kept in mind that the main object is to obtain 

a portion of coal which represents as nearly as possible the' entire 

delivery. The sample should contain about the same proportion of 

lump and fine coal as exists in the shipment as a whole. The practice 

of taking a shovelful near the bottom of the pile should be avoided, 

as the larger lumps of coal roll down and collect near the bottom and 

such a sample will not truly represent the coal.
METHODS OF SAMPLING AND TESTING. 23

These samples should be immediately deposited in a metal receptacle having a tight-fitting cover and provided with a first-class lock. 

Except when samples are being deposited or when the contents are 

being quartered down, this receptacle should be securely locked and 

ihe key held by a responsible employee. The receptacle should be 

placed in a comparatively cool location to avoid loss of moisture in 

the coal. When it becomes filled, or at the end of the sampling 

period, the contents should be emptied on a clean, dry floor, in a coneshaped pile. The larger lumps should be broken down by a coal maul 

or sledge, and the pile re-formed and quartered into four equal parts, 

a shovel or board being used to separate the four, sections. TAVO 

opposite sections should then be rejected and the remaining two again 

mixed, broken down, and re-formed into a pile to be quartered as 

before. This process should be continued until the lumps are no 

larger than pea size, and a quart sample is finally procured. The 

samples should then immediately be placed in suitable receptacles for 

shipping and sealed air-tight. The Geological Survey inspectors use 

a metal can 3 inches in diameter and 9 inches high, with a screw cap 

2 inches in diameter, for making shipments to the chemical laboratory. 

These cans are sealed air-tight by winding adhesive electrical tape 

around the joint of the screw cap. Each can holds about a quart, or 

2 pounds of coal.

The process of quartering down and preparing samples for shipment to the chemical laboratory for analysis should be carried on as 

rapidly as possible to avoid loss of moisture. The samples should 

be forwarded promptly and notice of shipment sent under separate 

cover. Receptacles should be marked plainly on the outside, and a 

corresponding number or description should be placed inside. A 

complete record of all deliveries should be kept, showing dates, 

names of contractor, kind of coal, total weight delivered, condition 

of coal (wet or dry), and any other particulars of importance.

The procedure at the chemical laboratory of the Geological Survey 

testing plant is described in Survey Bulletin No. 261. The samples 

are crushed and ground to a fine powder, and then analyzed and 

tested.

Persons not experienced in taking samples have a tendency to 

select a sample better than the average: In many cases a lump of 

coal is broken and shipped in a cloth sack to the laboratory. This 

allows the moisture to dry out; moreover, the lump selected is usually 

free from layers of slate and impurities and of course then represents 

the best coal in the lot, and shows a higher value than can be expected 

to hold throughout the coal delivered.

The preceding statements show that the purchaser should usually' 

have the quality determined on the basis of coal " as received," in 

order to correct any excess or deficiency in the moisture content. 
THE PURCHASE OF COAL UNDER SPECIFICATIONS.

ANALYSES Or COALS DELIVERED TO THE GOVERNMENT.

The following tables, giving the results of tests made by the 

Geological Survey on coal delivered to the Government Departments, 

are submitted in response to numerous recent.requests for information regarding the quality of coal which may be expected, and the 

variations in quality which may be found from month to month in 

coal delivered by the same dealer and" presumably from the same 

mine or group of mines:

Average analyses of anthracite coal delivered to all Government buildings in 

Washington, D. C., from December .1.5, 1.906, to April 26, .1.907. a

Dry coal:

Ash . .

B. t. u . - ._. ............

Coal as received:

B. t. u,. _ . _ - __ . _ _ . __ - ___ - __ ... . _ .

Furnace.

2.42

10.44

100.00

.79

13,408

4.08

Egg.

3.10

86.33

10.57

100.00

.98

13,523

Pea.

3.02

80.94

16.04

100.00

.80

12,487

4.81

11,886

Buckwheat.

2.42

^Q ftf

18.05

100.00

.68

12,107

5.09

11,485

0 Payment not based on chemical analysis. 

6 Separately determined.

Analyses of anthracite furnace coal delivered during .1907 to a Government 

building in Washington, D. C. a

Dry coal: 

Volatile matterFixed carbon. ...

Ash... ..... 

B. t. u ..

Coal as received:

B. t. u -

Jan. 29.

2.66 86.38- 

10.96

100.00

.78

13,297

4.13

12,749

Feb. 2.

2.85' 

86.34 

10.81

100.00

.78

13,435

4.19

12,874

Feb. 4.

3.32 

87.66 

9.02

100.00

.78

13,764

4.67

13,121

Feb. 9.

2.53 

86.65 

10.82

100.00

.78

13,418

4.41

12,826

Feb. 11.

3.06 

85.45 

11.49

100'. 00

.69

13,282

3.83

. 12,773

Feb. 12.

2.56 

86.69 

10.75

100.00

.84

iq Q«A

5.83

12,582

Feb. 14.

2.99 

86.63 

10.38

100.00

QD

13,427

4.99

19 7<V7

Feb. 15.

2.09 

86.15 

11.76

100.00

95

13,168

12,595

Dry coal:

Ash........ _ .... .........

B. t. u.. __ - ... ..

Coal as received:

B. t. u._ .... ... 

Feb. 23.

1.56

87.96

10.48

100.00

..93

13,094

3.06

12,694

Feb. 25.

1.62

87.77

10.61

100.00

.78

13,346

3.50

12,879

Feb. 26.

2.00

88.61

9.39

100.00

.74

13,655

3.93

13,118

Feb. 27.

3.34

85.12

10.54

100.00

.87

13,390

4 50

12,787

Feb. 28.

2.84

85.37

. 11.79

100.00

.86

13,166

^ fin

12,429

Mar. .13.

2.13

87.22

10.65

100.00-

79

13,421

0 19

13,136

Average.

2.51

86.74

10.75

100.00

81

13,363

4.24

19 7Qfl

a Contract for 4,500 tons. Payment not based _on chemical analysis. 

6 Separately determined.
COALS DELIVERED TO THE GOVERNMENT. 25

Analyses of anthracite egg coal delivered during 1907 to a Government building 

in Washington, D. C. a

Dry coal: 

Volatile matter. 

Fixed carbon ... 

Ash...:... _..__.

Sulphur 6 ... ....

B. t. u._ _ .....

Coal as received:

B. t. u .._.__.

Dry coal: 

Volatile matterFixed carbon __ 

Ash.... .......

B. t. u _____ .

Coal as received:

B. t. u ._._.

Jan. 29.

2.96 

86.29 

10.75

100.00

.98

13,423

4.18

12/863

Feb. 23.

' 3.60 

87.99 

9.40

100.00'

.94

iq 7Qo

4.15

13,174

Jan. 31.

2.83 

85.58 

11.59

100.00

.92

13,279

4.34

12,703

Feb. 25.

3.62 

86.00 

10.38-

' 100. 00

.98

13,643

3.64

1O OQ1

Feb. 5.

2.57 

86.27 

11.16

100.00'

.86

13,336

3.38

12,886

Feb. 26.

3.15 

86.58 

10.27

100.00

.99

13,608

4.07

no ne.*

Feb. 9.

3.90 

35.39 

10. 71

100.00

1.15

13,495

4.01

12, 953

Feb. 28.

3.22 

86.46 

10.32

100.00

1.13

13,617

4.13

13,055

Feb. 11.

3.17 

86.76 

10.07

100.00

1.06

13,588

4.11

13,030

Mar. 3.

2.86 

85.53 

11.61

100.00

1.02

13,293

3.15

12,874

Feb. 13.

3.53 

86.04 

10.43

100.00

.93

13,614

4.17

13,045

Apr. 2.

3.01 

87.59 , 9.40

100.00

.99

13,657

4.08

13,100

Feb. 14.

3.05 86.90' 

10.05

100.00

1.0 1

13,738

4.73

13,688

Apr. 19.

2.89 

86.93 

10.18

100.00

1.08

13,672

3.92

13,136

Feb. 15.

3.69 

86.36 

9.95

100.00

1.12

13,649

4.51

13,034

Apr. 24.

3.19 

86.36 

10.45

100.00

1.01

13,558

4.07

13,006

Feb. 21.

2.86 

85.72 

11.42

100.00

.97

13,328

4.23

12,764

Average.

3.41 

86.99 

9.60

100.00

.99

13,744

4.15

13,174

0 Contract for 9,000 tons. Payment not based on chemical analysis. 

6 Separately determined.

Analyses of anthracite pea coal delivered during 1906-7 to a Government 

building in 'Washington, D. C.a

Dry coal: 

Volatile matter-- 

Fixed carbon __ . 

Ash...............

Sulphur 6 __ . 

B. t. u ______ .

Coal as received:

B. t. u. __ .

Dry coal: 

Volatile matterFixed carbon __ . 

Ash _ .... . _ ....

B. t. u.. _ . __ .

Coal as received:

B. t. u .........

Dec. 22.

3.38 

80.51 

16.11

100.00

.60 

12,460

11,919

Feb. 13.

2.27 

82.45 

15.28

100.00

.92

12,300

5.20

11,660

Jan. 9.

2.58 

84.17 

13.25

100.00

.67 

12,883

4.62

12,286

Feb. 14.

2.32 

80.45 

17.23

100.00

.86

12,317

4.92

Jan. 24.

3.73 

81.34 

14.93

100.00

.99 

12,877

5.24

12,203

Feb. 18.

3.50 

78.75 

17.75

100.00

1.05

12,160

4.58

Jan. 28.

3.07 

82.16 

14.77

100.00

1.01 

12.835

3.40'

12,399

Feb. 19.

3.00 

81.35 

15.59

100.00

.89

5.23

Jan. 31.

3.33 

80.22 

16.45

100.00

.87

5.62

11,876

Feb. 25.

2.13 

83.24 

14.63

100.00

68

12,627

5.02

Feb. 5.

3.39 

80.80 

15.81

100.00

.78 

12,623

5.86

11,883

Mar. 18

2.50 

80.83 

16.67

100.00

80

12,410

3.85

11,932

Feb. 6.

4.06 

79.37 

16.57

100.00

.70 

12,555

4.27

12,019

Apr. 1.

2.49 

79.45 

18.06

100.00

69

19 rtQQ

2 97

Feb. 7.

3.30 

80.57 

16.13

100.00

.77

5 50

11,862

Apr. 8

2.51 

81.00 

16.49

100.00

.64

19 9Q.1

11,649

Feb. 11.

3.77 

79.95 

16.28

100.00

.71

6.04

11,668

Apr. 12

2.74 

81.24 

16.02

100.00

.77

12,479

Q 77

19 flflft

Feb. 12.

3.23 

80.09 

16.68

100.00

.68

1^> Q52/1

5

70

11,668

Average.

3.02 

80.94 

10.04

100.00

QA

12,487

0 Contract for 6,000 tons. Payment not based on chemical analysis. 

6 Separately determined.
26 THE PURCHASE OF .COAL UNDER SPECIFICATIONS.

Analyses of anthracite buckwheat coal delivered during 1906-7 to a Government 

building in Washington, D. C.a

Dry coal: 

Volatile matter. 

Fixed carbon.,1 

ASh.____...__..--

:B. t. u- .. _

Coal as received:

B.-t.u... ........

Dec. 18.

2.50 

80.34 

17.16

100.00

.63 

12,245

. 4.79 

11,659

Dry coal: 

Volatile matter... 

Fixed carbon __ . 

Ash...............

B. t. u ......- _

Coal as received:

B. t. u- ___ ....

Feb. 7.

1.78 

76.91 

21.31

100.00

.67 

11,635

5.51 

10,993

Jan. 15.

1.93 

82.40 

15.67

100.00

.73, 

12,475

5.591 

11,776

Feb. 12.

2.66 

80.03 

17.31

100.00

.70 

12,350

5.36 

11,609

Jan. 16.

2.21 

80.94 

16.85

100.00

.68 

12,314

4.47 

11,763

Feb. 15.

2.59 

79.34 

18.07

100.00

.77 

 12,098

5.57 

11,016

Jan. 22.

2.49 

80.72 

16.79

100.00

.67 

12,370

4.93 

11,755

Mar. 2.

2.07 

76.90 

21.03

100.00

.70 

11,749

6.10 

11,032

Jan. 23.

2.41

76.32 

21.27

100.00'

.67 

11,574

5.32 

10,959

Mar. 20.

2.87 

81.56 

15.57

100.00

.62 

. 12,545

4.60 

11,968

Jan. 28.

1.98 

79.38 

18.64

100.00

.67 

11,970

4.38 

11,445

Apr. 3.

2.11 

79.52 

18.37

100.00'

.77 

12,109.

4.31 

11,587

Jan. 31.

3.23 

78.61 

18.16'

100.00

.67 

11,843

5.13 

11,236

Apr. 13.

2.62 

79.36 

 18.02

100.00

.69 

12,071

. 5.64 

11,390

Feb. 4.

2.89 

80.57 

16.54

100.00

.60 

12,265

4.69 

11,081

Average.

2.42 

79.53 

18.05

100.00

.68 

12,107

5.09 

11,485

0 Contract for 5,000 tons. Payment not based on chemical analysis. 

6 Separately determined. ,

Analyses of bituminous coal delivered during 1906-1 to a Government building 

« 'in Washington, D. C., as being run-of-mine from Georges Creek.

Dry coal:

Ash............. ........... ... ...

B. t. u - __ 

Coal as received:

B. t. u. ___ .. .. __ . _____ ...

Dec. 27.

16.84

73.01

10.15

100.00

1.02

14,017

4.80

13,343

Jan. 3.

16.24

75.07

8.69

100.00

.93

14,364

2.77

13,966

Jan. 22.

17.26

75.27

7.47

100.00

1.03

14,636

3.43

Jan. 23.

17.03

76.23

6.74

100.00

1.08

14,764

4.22

14,141

Jan. 30.

16.43

75.11

8.46

100.00

.80

14,441

3.09

13,995

Feb. 6.

16.66

75.57

7.77

100.00

.94

14,586

Q 71?

14.040

Dry coal:

Ash. __ . _ .-. ___________

Sulphur 0 _ . . __________

B. t. u __ .. __ .._..__...._. ___ .

Coal as received:

B. t. u ..-. -_... .-..._..-......

Feb. 9.

16.21

74.99

8.80

100.00

Qf;

14,317

4.07

13,734

Feb. 15.

15.77

75.12

9.11

100.00

99

14,308

3 19

13,862

Mar. 28.

Tfi 9Q

74.55

9.16

100.00

1.03

14 264

3.15

13,815

Feb. 21.

16.42

74 79

Q 70

100.00

QC

14,352

2.94

TO QQfY

Apr. 15.

15.76

76.89

7.35

100.00

on

14,632

2 97

14,197

'Separately determined.
THE PURCHASE OF COAL UNDER SPECIFICATIONS. 27.

SOME PUBLICATIONS ON COA1L.

The following are a few of the Survey publications on coal. A 

more complete list is given in Bulletin No. 316, pages 518-532. The 

reports here named are now available for distribution. Others are in 

press and still others are in preparation. Applications for these 

reports, except for Bulletin No. 261 and Professional Paper No. 48, 

should be addressed to The Director, United States Geological 

Survey, Washington, D. C.

Bulletin No. 261. Preliminary report on the operations of the coal-testing 

plant of the United States Geological Survey at the Louisiana Purchase Exposition, St. Louis, Mo., 1904. E. W. Parker, J. A. Holmes, M. R. Campbell, committee in charge. 1905. 172 pp. Out of stock. Can be obtained by sending 10 

cents in cash to the Superintendent of Documents, Washington, D. C.

Professional Paper No. 48. Report on the operations of the coal-testing 

plant of the United States Geological Survey at the Louisiana Purchase Exposition, St. Louis, Mo., 1904. E. W. Parker, J. A. Holmes, M. R. Campbell, committee in charge. 1906. In three parts. 1492 pp., 13 pis. Out of stock.. Can 

be obtained by sending $1.50 in cash to the Superintendent of Documents, 

Washington, D. C.

Bulletin No. 290. Preliminary report on the operations of the fuel-testing 

plant of the United States Geological Survey at St. Louis, Mo., 1905. By J. A. 

Holmes. 1906. 240 pp.

Bulletin No. 323. Experimental work conducted in the chemical laboratory 

of the fuel-testing plant, St. Louis, January 1, 1905, to July 31, 1906. By N. W. 

Lord. 1907. 49 pp. ,

Bulletin No. 325. A study of four hundred steaming tests made at the fueltesting plant, St. Louis, Mo., 1904, 1905, and 1906. By L. P.. Breckenridge. 

1907. 196 pp.

A few miscellaneous references of special interest may be given, 

as follows:

Bement, A. The testing of coal. Western Society of -Engineers.

Electrical World. Editorial, April 6, 1907.

Engineering Record. Editorial, April 13, 1907.

Parr, S. W. Composition and character of coals. Bulletin No. 3, Illinois 

Geological Survey, Urbaua, 111.

Preliminary report of committee on coal analysis. Journal of the American 

Chemical Society, vol. 20, 1898.

Report of the committee on coal analysis. Journal of the American Chemical 

Society, vol. 21, 1899.

Voorhees, S. S. Analysis of coal. American Society for Testing Materials, 

3907.

Wood well, J. E. The purchase of coal. American Society for Testing Materials, 1&07; Mines and Minerals, September, 1907.

CLASSIFICATION OF THE PUBLICATIONS OF THE UNITED STATES GEOLOGICAL

SURVEY.

[Bulletin No. 339.] . '

The serial publications of the United States Geological Survey consist of (1) 

Annual Reports, (2) Monographs, (3) Professional Papers, (4) Bulletins, (5) Mineral 

Resources, (6) Water-Supply and Irrigation Papers, (7) Topographic Atlas of United 

States folios and separate sheets thereof, (8) Geologic Atlas of the United States 

folios thereof. The classes numbered 2, 7, and 8 are sold at cost of publication; the 

others are distributed free. A circular giving complete lists can be had on application.

Most of the above publications can be obtained or consulted in the following ways:

1. A limited number are delivered to the Director of the Survey, from whom they 

can be obtained, free of charge (except classes 2, 7, and 8), on application.

2. A certain number are delivered to Senators and Representatives in Congress 

for distribution.

3. Other copies are deposited with the Superintendent of Documents, Washington, 

D. C., from whom they can be had at practically cost.

4. Copies of all Government publications are furnished to the principal public 

libraries in the large cities throughout the United States, where they can be consulted 

by those interested.

The Professional Papers, Bulletins, and Water-Supply Papers treat of a variety of 

subjects, and the total number issued is large. They have therefore been classified 

into the following series:. A, Economic geology; B, Descriptive geology; C, Systematic geology and paleontology; D, Petrography and mineralogy; E, Chemistry and 

physics; F, Geography; G, Miscellaneous; H, Forestry; I, Irrigation; J, Water storage; K, Pumping water; L, Quality of water; M, General hydrographic investigations; N, Water power; 0, Underground waters; P, Hydrographic progress reports, 

Q, Fuels; R, Structural materials. This paper is the tenth in Series Q, the complete list of which follows (PP=Professional Paper; B=Bulletin):

SERIES Q, FUELS.

B 261. Preliminary report of the operations of the coal-testing plant of the United States Geological

Survey at the Louisiana Purchase Exposition, St. Louis, Mo., 1904; E. W. Parker.J. A.Holmes,

M. R. Campbell, committee in charge. 1905. ,172 pp. 

PP 48. Report on the operations of the coal-testing plant of the United States Geological Survey at the

Louisiana Purchase Exposition, St. Louis, Mo., 1904; E. W. Parker, J. A. Holmes, M. R. Campbell, committee in charge. 1906. 3 parts. 1,492pp., 13 pis. 

B 290. Preliminary report on the operations of the fuel-testing plant of the United States Geological

Survey at St. Louis, Mo., 1905, by J. A. Holmes. 1906. 240 pp. 

B 323. Experimental work conducted in the chemical laboratory of the United States fuel-testing

plant at St. Louis, Mo., January 1,1905, to July 31,1906, by N. W. Lord. 1907. 49 pp. 

B 325. A study of four hundred steaming tests made at the fuel-testing plant, St. Louis, Mo., in 190-1,

1905, and 1906, by L. P. Breckenridge. 1907. 196 pp. 

B 332. Report of the United States fuel-testing plant at St. Louis, Mo., January 1,1906, to July 1,1907,

Joseph A. Holmes in charge. 1908. pp. 

B 333. Coal-mine accidents: their causes and prevention; a preliminary statistical report, by

Clarence Hall and W. 0. Snelling, with an introduction by J. A. Holmes. 1907. 21 pp. 

B. 334. The burning of coal without smoke in boiler plants, a preliminary report, by D. T. Randall.

3908. 26pp. 

B 336. Washing and coking tests of roal and cupola tests of coke, by Richard Moldenke, A. W.

Belden, and G. R. Delamater. 1908. pp. 

B 339. The purchase of coal under Government and commercial specifications, on the basis of its

heating value, by D. T. Randall. 1908. 27pp.

Correspondence should be addressed to

THE DIRECTOR,

UNITED STATES GEOLOGICAL SURVEY,

WASHINGTON, D. C. 

JANUARY, 190£.

I

o