Annual Report

of the

Director of the Bureau of Standards

to the

Secretary of Commerce and Labor

for the

Fiscal Year Ended June 30, 1908

Washington

Government Printing Office

1909



Annual Report

of the

Director of the Bureau of Standards

to the

Secretary of Commerce and Labor

for the

Fiscal Year Ended June 30, 1908

Washington

Government Printing Office

1909

' REPORT

OF THE

DIRECTOR OF THE BUREAU OF STANDARDS.

Department of Commerce and Labor.

BuREAiT OF Standards,

Washington^ July i, 1908.

Sir : I have the honor to submit the following report of the work

of the Bureau of Standards for the fiscal year ended June 30, 1908

:

DIVISION I.—ELECTRICITY.

The Avork of the electrical division of the Bureau comprises

photometry as well as electricity and magnetism. Each subject involves scientific investigation and the practical application of the re-

=^ults of such investigations to the improvement of electrical standards

and the testing and verification of instruments and materials.

The work of this division has been of three kinds

{a) piire re- search; (/;) the investigation of methods of measurement and of

testing, the design and construction of instruments for use in testing,

the purchase, testing, and installation of equipment; and (r) the test- ing of instruments and materials for the ])ublic and the departments

of the Government. It has been the policy of the Bureau from the

outset to establish each line of work i;pon a rigorous scientific basis

before undertaking actual testing for the pujilic. A single test frequently involves extended research. Many of the tests are difficult

and involve considerable theoretical knowledge as well as instrumental equipment. The electrical tests made during the year, 337

in all, include a wide variety of electrical standards, instruments, and

materials. The research work done h\ the I)ureau. the results of

which have been jjublished from time to time, has given it a high

standing in the electrical world. The classical researches of Lord

Rayleigh and others of a generation ago laid the foundation and set a high standard for work of this kind. But the order of accuracy

now demanded in absolute measurements is at least ten times as great

as then. This not only requires better instruments and facilities,

but also refinements of theory and extended investigations of possible sources of error, which vastly increase the labor and time required.

3
4 REPORT OF DIRECTOR OF BUREAV OF STANDARDS.

ICLECTKICAL KKSISTAN ( K AND i:Ll-:( TKOMOTIVE FORCE.

The increased application of electrical methods to many classes of

physical investigations and the more rigorous specifications for cer- tain classes of commercial electrical apparatus has materially increased the testing work of the section. In ordei' to reduce the time

required for some of these tests and to facilitate the intercomparison

of standards belonging to the Bureau, some new shunt-compensated

resistance apparatus lias been designed and is now under construction. The apparatus consists of a number of 1 : 1 and 10:1 ratio

coils, and a multiple ratio box furnishing all the ratios met with in

practice.

The investigation of standards of electromotive force referred to in

previous reports has been continued and extended and further comparisons have been made between the Weston standard cells of the

Bureau and those of the English National Physical Laboratory.

The results have fully substantiated the accuracy of reproduction of

several ]Darts in one hundred thousand previously claimed. Tn addition, the cooperation of a number of American physicists, chemists,

and physical chemists has been enlisted, with the object of testing

the preliminary specifications proposed by the Bureau for the construction of Clark and Weston cells. On the basis of the results attained at the Bureau and elsewhere,

the Bureau of Standards has been convinced of the superiority of

(he standard cell over the coulometer as a fundamental electrical

standard. This position, which has been indorsed by a joint couimittee of the American Physical Society, the American Institute of

Electrical Engineers, and the American Electrochemical Society, will

therefore be advocated at the forthcoming International Electrical

Conference.

During the year a redetermination of the tempei'ature formula of

the Weston cell has been completed. The results show that the

formula heretofore accej^ted does not correctly represent the changes

in electromotive force with temperature below 10° and above 30°.

The difference within the above range between the tAvo formula^ are

smaller, but must be taken into account when the liighest precision

is sought. A large amount of further work has been outlined and will

receive attention as soon as time permits.

INDUCTANCE AND CATAf TTV AND ABSOIAITE :\rEASUKEMENTS.

In inductance and capacity measurements great progress has been

made and a considerable program of work has been laid out for the

7iext few years. The iuA'estigation of the ratio of electrical units in

progress for three years was brought to a successful conclusion during

the year and has been published in the Bulletin. This ratio is of fun-
KKPORT OK DIRKCTOR OF BUREAU OF STANDARDS. 5

(lamental iniportance in electrical measurements, and this investigation has fixed its value much more exactly than heretofore known.

The current balance work is making good progress; much has been

learned about the problem, and an improved form of the balance is

under construction. Such work is so exacting and the difficulties so great that satisfactory progress can not be rapid. In the work on the

new sealed standards of resistance enough has been done to demonstrate the great advance which has been made by their development in

precision resistance work.

The practical units in terms of which all electric current and power

are measuied in this country are fixed by act of Congress, but in order

that the iniits shall be the same throughout the world international

conferences or congresses have been held from time to time to agree

upon the values of these units. The units now in use were agreed

upon at the International Electrical Congress held in Chicago in 189o,

and they were enacted into law by act of Congress approved July 12.

1894. Subsequent investigation has shown the necessity for slight

changes in some of the units and a revision of the law. For this rea- son and in view of the meeting of the International Conference on

Electrical Units and Standards, to be held in London. October 12-21,

iOOB, considerable work has been done during the year on the improvement of the standards of electromotive force and standards of resistance, and on the determination of electric current in absolute measure. These researches are just now of special importance. The results of

the above investigation will be presented to the conference and will no

doubt form an important factor in the conclusions.

ELECTRICAL ^rEAST'RING IXSTRl'MEXTS.

The number of electrical measuring instruments tested during the

l)ast year is nearly double that for the preceding year; instruments

of various types and widely differing ranges being tested for the

public. Other work done in this section included the study of new

commercial instruments luider varying service conditions; the test- ing of insulated wire and insulating joints for breakdown voltage;

tests of inclosed fuses, dry cells, and the electrical properties of

materials. A special electric heating device, submitted by one of the

branches of the government service, was tested, and experiments wei-e

made with a view^ to imxDroving this device and lowering its cost. Such an improved apparatus was constructed in the instrument shop

of this Bureau and given a thorough test. A new instrument has

I)een designed for the i-apid measurement of current and voltage,

which will materially reduce the time required for many electrical

instrument tests.
6 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

MAGNETISM.

Problems have been studied involving- the measurement of the

magnetic properties of iron and steel, including soft iron in thin

sheets, so extensively used by manufacturers of electrical machinery.

The Bureau is now in a 2:)Osition to do this important work for the

public. There is a greater diHerence in the quality of iron employed

by manufacturers of electrical machinery than i-; generall_y appreciated, and this is mainty due to the difficulty of testing samples.

Now that the Bureau, is in a position to test such samples, it is possible to determine whether iron supplied for such purjDOses conforms

with specifications. The Bureau standardizes the test bars and instruments used in magnetic testing and has done considerable work

in improving the instruments and methods employed in magnetic

measurements.

PHOTOMETRY.

The photometric work of the Bureau includes the study of problems

arising in the accurate measurement of light sources and standards

of candlejDOwer, the testing and certification of such standards, and

the inspection and testing of electric lamps purchased by the Government. The work in the photometric section during the past fewyears has been of great imioortance. and the high standard that has

been set should be maintained. The Bureau maintains the standard

of candlepoAver for the electrical industries of the country, thereby

insuring uniformity in the measurement of illumination and in the

rating of electric lamps. An effort is being made to secure uniformity

in the vahie of the standard candle in England. France, and America,

by a very slight modification of tlie units at present employed, and

iilso to induce the gas industry of this country to adopt the modified

unit, so that a candlepower Avill mean tlie same thing in gas and

electric lighting. The present difference is small, and such a uniformity in the- A^alue of the unit would be advantageous, and would

proliably result in greater uniformity in the measurements of the

illuminating value of gas in the different cities of the country. The

Bureau has been of service to the electric-lighting industry hj bringing the various manufacturers of lamps into agreement as to the

candlejx)wer unit, and (lie same ought now to be done for the gas

industry. The use of flame standards will probably be continued for

some time at least by the gas companies. A careful photometric

investigation of flame standards and ffas flames should be made.

DIVISION II.—WEIGHTS AND MEASURES.

The Bureau has cooperated with the state governments in establislning efficient inspection services, and during the year new evidences of interest and improvement have developed. The Territory

of New Mexico procured and submitted to the Bureau for verifica-
KEPOKl" OF DIRECTOR OF BUREAl' OF STANDARD!?. 7

tion a set of state standards and six sets of secondary standards for

the use of as many local sealers, thns setting a worthy example to

States in the protection of honest merchants and the public. Data

was furnished the chief officials of weights and meastires in the

'states of Xew Jersey. Ohio. Tennessee, and Virginia as to proper

laws, and in the first-mentioned State a new law, based uj^on the

model law adopted by the Com-ention of State Sealers, was enacted-.

^Nfany inquiries for information and appeals for assistance were re^

ceived fi'om individuals in localities wh.ere inspection is inefficient or

entirely lacking.

V.liile the inspection of commercial weights and meastires may be

lel^ to the state and local authorities, the weights and sizes of packages, barrels, crates, etc., should be defined by national laws, since

commodities sold in such containers are invariably packed in one

State and sold in others. In addition to answering numerous inquiries as to the standards used in selling certain commodities in

different States, much information has been furnished to commercial

and industrial bodies concerning the laws and practices of foreign

countries. The demand for information of this character necessitates the establishment of some efficient means for systematically

obtaining such data.

The demands uj)on the division from all sources are growing rapidly, tlie largest increase from any single source lieing from the Bureau

of Chemistry of the Department of Agriculture. The enactment of

the pure-food law necessitated the purchase of large amounts of

volumetric apjDaratus and weights, all of which is purchased according to the specifications prepared by this Bureau and is examined

as to its compliance with them.

Altogether al)()ut :5.000 pieces of glass volumetric apparatus have

been tested, most of which conformed to specifications. The larger

part of this testing has been for government departments. New

forms of standard pipettes, for simplify ing and reducing the work of

testing flasks, pipettes, and burettes, have been developed. These

pijDettes for testing pij^ettes and burettes operate b}- direct volumetric

measurements and thus obviate weighing each volume of water delivered. In flask testing these i^ipettes are automatic in operation,

not requiring to be read, and are used in conjunction with a burette.

The testing of smaller metal-capacity measures by means of glass

pipettes has been used successfully, along with the weighing method,

to shorten the time of the complete test of a measure. A larger number of gas cubic-foot standards and other capacity measures have been

tested than heretofore.

The improvement in the quality and accitracy of volumetric apparattis now supplied by manufacturers to departments letting contracts on Bureau of Standards specifications has been stich as to prove the

73260—09 2
8 REFOKT OF DIKECTOR OF BUREAU OF STANDARDS.

necessit}' of this -work. The specifications for volumetric apj)aratus

have been revised and such changes and additions made as four years"

experience indicated were desirable.

Two hundred and eightA^-two standard engineer's tajDes were tested

during the year. Advance has been made in the standardization of

the. new bench for steel tape measurements, the calibration having

been partlj' made, approximate coefficients of the two bars determined, and some work done toward establishing the total length.

Approximate determinations of the coefficients of expansion of several nickel-steel tapes were made for the Coast and Geodetic Survey,

for the Geological Survey, and for other institutions; a number of

meter bars and shorter standards have been tested, as well as manufacturers' disk gauges and end standards. A comparator has been

fitted up south of the Physical Laboratory for use in approximate

determinations of the coefficient of expansion of 50-meter tapes.

Information has been obtained regarding nickel steel as a material

for meter bars, but more work is necessary before arriving at any

conclusions.

The problem of establishing standard scales for hydrometers was

given attention and important residts accomplished. Before the

question was taken up by the Bureau a variety of scales Avere in use.

all purporting to give the same data, causing endless confusion among

manufacturers and the industries in which such instruments are vised.

A new form of hydrometer comparator has been developed having

as its essential feature the production, by simple manipulation, of a clean surface of liquid in which to comjDare hydrometers, thus obviating the use of special liquids not affected by surface contamination.

A preliminar}' design has been constructed and put into operation for

testing commercial instruments and for 2)recise calibration of the

primary standards of this Bureau, with xery satisfactory results.

There was an unexpected increase in the demand made on the

Bureau for the testing of standards of mass for the States, corporations, and individuals, the number of weights tested being 1.3!) 1. Data are being gathered as to the constancy of weights of different

materials, but Avhile strilving changes have been noted definite results can be obtained only from observations extended over several j'^ears,

Tables are being prejiared to assist in correcting weighings for moisture in the air. The testing of weights has nearly doubled during

the 3'ear, without extra assistance being provided. The extra work

was provided for by developing rapid methods and apparatus and

by deferring important investigations, much to the detriment of the

Bureau's general efficiency.

Although the Bureau acquired a set of platinum-iridium standards,

from 500 grams to 1 milligram, over five years ago, no opportunity

has presented itself to calibrate^ them, notwithstanding the fact ihv.t
KKPOiri' OK DIKKCTOK OF HURKAU OK STANDARDS. 9

the weights are urgently needed. It is hoped that an opportunity to complete this long-deferred investigation Avill present itself during

the coming year. Manufacturers are beginning to realize the necessitj of a higher standard in the constritction of precision weights.

The Bureau cooperates by furnishing expert advice, specifications,

models, and calibrating the maker's standards. A decided improvement is alread}' noted in this important line of measuring apparatus.

Tn connection with the work of time measurements the determina- . tion of the rates of a number of watclies loaned to the Bureatt for this

purpose was taken up. Data was obtained for use in drafting regitlations for testing the best grades of stock watches, especially as to the

criteria for granting certificates. The first test ran four months, the

series of runs in ditferent positions l)eing repeated to determine the

accuracy with which a watch will repeat its performance ttnder fixed

conditions. A clock room for the Riefler standard clock is now being

fitted up in the basement of the Physical Laboratory. A chronogra^jh for the testing of time-measuring instruments is also under

construction in the sho]^.

DIVISION III.—THERMOMETRY, PYROMETRY, AND HEAT

MEASUREMENTS.

Many urgent requests are being recei\ ed for the determination of

heat constants and the distribution of standardized materials. These

include the calorific values of pure substances for the standardization

of calorimeters used by engineers and chemists, the preparation and

distribution of such substances, the determination of tlie calorificvalues of industriallj^ important gases, the standardization of calorimeters on which are based purchases of coal and other combustibles.

An intercomparison of the various forms of calorimeters used in industrial work is very desirable. Requests for work in this field come

not alone from individuals and corjjorations, but also from publicutility commissions, who need such data in connection with the preparation of specifications and regulations.

The application of scientific methods to industrial processes at high

temperattires is of growling importance, and the demands on the

Bureau for data and experimental determinations include the test- ing of in.struments used for measuring high temperatures, on whose

indications are dependent the product of many industries, the determination of melting points, specific heats, conductivities, and emissivities of various substances, the properties of refractory materials,

and the critical points of steels and other alloys.

The clinical thermometers submitted remain about constant in number, and appear to be the best grades of the several manufacturers.

The Bureau has continued the practice of loaning standard thermometers to the manufactui'ers of clinical thermometers with most
10 KKPOH'r OK DIKEC'POH OF BUREAr OK ^TAXDAKDS.

satisfactoiy results, the accuracy of practically all the product of

American manufacturers being controlled by standards loaned them

by this Bureau.

The manufacturers of high-grade thermometers, including especially those for use at high temperatures, have very generally adopted

the methods of annealing recommended by this Bureau as a result of

ii long series of experiments; hence it is no longer necessary to send

abroad for satisfactory instruments of this class. Several manufacturers have installed annealing furnaces and testing plants from

plans furnished by this Bureau. An increasing percentage of the

thermometers submitted for test require calibration of the highest

accuracy, such as calorimetric thermometers and certain grades iised

in chemical and high-temperature measurements.

Many of the pyrometers tested arc the standards used hy manufacturers of such instruments. Nearly all American manufacturers

and agents of these instruments now have their product controlled

by standards furnished by this Bureau. There is beginning to be

a satisfactory uniformit}^ in the indications of high-temperature

measuring instruments in this country, whereas previously there was

ii most chaotic condition in this important field.

The Bux-eau has rendered assistance to manufacturers in the designing and testing of new types of high-temperature instruments

and in the development of new methods of measurement. The

assistance which the Bureau has been able to render in this way has

apparently encouraged sevei'al firms to imdertake the manufactiuv

and introduction of pyrometers into industrial use. The establishment and maintenance of correct standards is of

fundamental importance. From the nature of the problem no concrete standards can be constructed for temperature measurement

and the scale must constantly be reestablished and checked, which

involves a large amount of Avork and time. It is only within the

limited range of temperatures of 0° to 100° C. that the Bureau has

yet been enabled to maintain a standard temperature scale with

adequate accuracy. No work has yet been attempted on the lowtemiDerature scale, and only a start has been made on the hightemperature scale. Preliminary work has been done toward the

establishment of the high-temperature scale to 2,000° C, by means

of the laws of radiation; and for the interconiparison of the hightemperature scales as given by electrical-resistance, thermo-electric,

optical, and total-radiation methods.

The work in heat measurements has been mostly investigational, or

in connection with cases of disagreement between litigants involving

unusually extended experimental work. Such heat measurements

include tests of inflauunatory materials, melting points of metals.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 11

liehavior at high temperatures of metals, bricks, and other materials,

jind cooling curves of steel. In collaboration with the American Society for Testing Materials,

exhaustive tests of samples of lubricating oils from various sources,

hy different methods, have been begun by this division.

Work on the thermal projierties of the materials used in the new

filament lamps has been undertaken, but is not completed. It was

liojDed to be able to determine the melting points of some of the ver}^

refractoiT metals both in the form of filaments and in tbe form of

minute particles by a new radiation method; but this work has thus

far been limited to the determination of the melting points of

tungsten and tantalum in the form of filaments.

The introduction in the industries of radiation methods of measnring high temperatures requires the detei'mination of the erroi's of

such instx'uments when examining incandescent sukstances, such as

iron, copper, fire brick, etc. A few preliminarj^ measurements have

been made on the radiation from iron. Some experiments have

been made on the constancy of melting of certain refractory metals

in order to define and construct a new standard of light based on

the intensity of light emitted from an inclosure immersed in a metal

at its freezing point. A study has been made of the available

methods of obtaining cooling curves for the thermal analysis of

steels, alloys, and chemical compounds, the results of which have

been published in the Bulletin.

The determination of the specific heats of brine solutions, data of

great value for the refrigerating industries, has been nearly completed and a preliminary I'eport published. A new type of vacuum

jacket calorimeter suitable for the determination of specific heats at

low temperatures has been developed, and several very sensitive re- sistance thermometers have been designed and constructed for calorimetric work. It is hoped that the work in calorimetry may be greatly

extended, and certain gas calorimeters have been acquired with a

A'iew to an examination of their behavior.

The apparatus is being assembled for repeating and extending the

Avork of Joule and Thomson on the free expansion of gases, a problem

fundamental to the conception and measurement of temperature.

There were tested during the year 9,193 thermometers, including

202 high-temperature thermometers, 530 laboratory and special thermometers. (50 low-precision industrial thermometers, and 8,395 clinical thermometers; 9 optical pyrometers, 41 thermo-electric pyrometers, 12 resistance p3'rometers; 99 viscosity and fiash-point tests of

oils; and IT other tests involving heat measurements; in all about

9,351 separate tests. There was a considerable increase over the preceding year in the testing of high-grade mercurial thermometers and

in oil tests for the United States Government.
12 REPORT OF DTRECTOR OF BT'REATT OF STANDARDS.

DIVISION IV.—OPTICS.

Sl'ECTROSCOl'V.

Important investigations have been conducted in this section of

tlie Bureau during the year. Work on the helium tube as a possible

primary light standard has been continued. Age tests and the effect

of varying the glass of the stem remain to be carried out. The purity

of spectral light sources has been investigated further, recent work

being devoted to the structure of composite lines. The intensity of

any spectrum line was shown to be probably expressible in terms of

but a single variable and two constants whatever the form of excitation of luminescence. The relation of light to radiation and visual

sensibility has been examined in more detail, and practical deductions drawn.

The structure and properties of comjiound lenses have been studied,

particularly the effect of the position of the transverse axis on astigmatism and distortion. Preliminary specifications suitable for defining lens sjDced " were drawn up and applied to a photographic

lens with a Martin's photometer.

A nmnber of photographic lenses were tested as to fidelity of re- production. The transparency for visible and ultra-violet radiation

of a special absorption cell and of several samples of glass have been

examined. The refractive indices of two samples of glass and a fluid

were determined through the visible and ultra-violet portions of the

spectrum. A special design of spectrophotometer was constructed

and tested. A Lummer-Gehrcke plate and special camera for the

echelon have been added to the spectroscopic equipment, and a precision optical bench for lens te.sting is being designed and consti'ucted.

RADIOMETRY.

The measurement of radiant energy is still in a primitive state of

development, in pai'ticular its measurement in absolute units. This

is chiefly due to the fact that the radiation to be measured is generally

from a surface, the temperature of which is practically indeterminate,

as is also the energy expended within the radiating substance. The

measurement of the energy radiated is exceedingly difficult, but progress is being made in the development of apparatus and methods for

these measurements.

The recent development of processes which require an accurate

knowledge of temperatures necessitates a study of the laws of radiation of various materials with variation in temperature. This is notably true of metals used in incandescent laiups to ascertain the cause of their luminous efficiency. Three investigations of such materials have just been completed. An investigation of the Nernst
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 13

glower radiation shows that its emission spectrum is discontinuous at low temperatures, gradually becoming continuous at high temperatures. No " radiation constant " was found, so that the results of

previous experimenters are unreliable. An investigation of the radiation of solids in the form of electrically heated rods, and fine powder

iirought to incandescence on a heater, show the spectral partition of

energj^ which occurs in sharp emission bands, superposed upon a w^eak

:'ontinuous spectrum. The maximum emission moves toward the

short wave lengths with temperature rise; but the bands remain

fixed in position, simply increasing in intensity—a result entirely

unexpected from previous observations in the visible spectrum.

The most important constant which occurs in the spectral radiation

formula of metals, such as platinum, osmium, tungsten, tantalmn, etc., in the form of filaments in incandescent lamps, has been investigated.

This iDarticular radiation •' constant " also occurs in Stefan's laAv of

total radiation, where it is given as -1 for a complete radiator. This

important so-called constant was, however, found to decrease with

rise in temperature, with a value higher than platinum at any given

temperature. This accounts for the high luminous efficiency of metal

filament lamps, and incidentally verifies the theory which requires

the optical constants of the metals to be a function of the temperature

and the Avave length. This seems to have escaped the attention of

l^revious experimenters.

Numerous inquiries concerning radiometers, the transparency of

gases for heat waves, and of absorption screens for infra-red work

have been received and appi'ojiriate information given.

I'Or.ARIMETRV.

Polarized light is utilized in testing all sugars bought and sold or imported. The polariscope and its accessories are therefore the indispensible adjuncts of the sugar refiner, the beet and cane sugar

planter, and sugar laboratories, but such apparatus has remained unstandardized. Hence it is futile to expect tests by various interests

to agree when not only apparatus but methods of testing differ so greatly. After extended investigation of the theory and practice of

polarimetry, the basis of standardization of polarimetric apparatus is

now rigidly defined by this Bureau. During the year a number of

(|uartz plates and 1,270 samples of sugar for the Treasury Department were tested by this section.

The most important piece of work of (he year was the successful

development of a quartz compensating polariscope with adjustable

sensibility. The theory and construction of (his instrument are described in the Bulletin, and it has been adopted by the Secretary of

the Treasury for use in the customs service.
14 EEFOKT- OF DIEECTOB OF BUREAU OF STAi4DAEDS.

The disturbing effect of atmospheric conditions on raw sugar tests

is appreciable, as an investigation begun over a 3^ear ago clearly shows.

This work will be continued until satisfactory correction has been

obtained.

Large quantities of pure sugar are indispensable for research work

in polarimetry, and numerous requests from A'^arious sources have

been received during the past year for such sugar for calorimetric and

other purposes. To meet these demands apparatus for preparing

pure sugar by recrystallization has been developed. The Bureau will soon be able to produce standard sucrose in large quantities under

controlled conditions which guarantee a high degree of purity.

A new optical system giving monochromatic light when used with

intense sources has been developed for use in polariscopic work, and

a compact form of apparatus is being designed.

DIVISION v.—CHEMISTRY.

The chemical division has been actively ;issisting government departments as well as the Printing Investigation Commission of Congress. The investigations commenced or continued on behalf of the

deiDartments and the Government Printing Office, and in which more

or less progress has been made, I'elate to the testing of materials in

connection with contracts and purchases. The work is of importance,

not only to ascertain Avhether supplies furnished by contractors con- form to specifications, but also as a j^reliminary to the formulation

of specifications for future use where none is now insisted on. There

is a wide field of chemical usefulness open to the Bureau in lines

of research relating to the purchase of government supplies. The

reseai'ches aiming at improvement in the quality of and methods of

testing these materials have hardly more than begun, and will con- sume much time if results of real value are to be expected. In order

to expedite this work and permit such routine testing as will be called

for, a considerable addition to the working force and laboratory space

is imperative.

The classes of problems planned and under investigation for the

Government are numerous, and in all about 1,7G6 tests and anal^^ses

have been reported in the following classes during the yeai-

:

(1) Testing of writing, printing, copying, and carbon papers;

writing, copying, record, and typewriter inks; typeAvriter ribbons;

mucilage and sealing wax, and researches bearing on the preparation

of suitable specifications, with a view of improving the quality, re- ducing the cost, and rendering the Government more independent of

manirfacturers than at i^resent. There have been reported by the

Bureau about 1,595 tests and analyses of papers, inks and ink powders,

printer's ink, and mucilage.
BBPOET OF DIEECTOK OF BUREAU OF STANDARDS. 15

(2) Tests and analyses of lubricating oils, linseed oils and driers,

23aints and varnishes, of which 139 separate tests have been made during the year.

(3) Miscellaneous tests of soaps, rubbers, metals ;ind alloys, and

other materials, about 32 in number.

(-t) Analyses of standard steels intended for distribution to all who wish to test the accuracj' of their own chemical work and that

of their employees. The increasing demand on the part of those en- gaged in the iron and steel industries, and of analysts and others, for

the standard irons and steels, we have been preparing with the assist- ance of the American Foundiymen's Association and the Association

of American Steel Manufacturers, and the continued expression of

interest in the subject, shows the value of this line of work. Of the

irons and steels thus far prepared 465 separate samples were supplied

to applicants during the year.

Further expansion is needed to meet the demands for cooperation on the i^art of other divisions of the Bureau. Cooperative problems

pressing for solution that can not be solved without the aid of chemistry are: (1) The preparation and testing of pure materials used in

the construction of standards of electromotive work ; (2) the prejDaration of many substances of the very highest degree of purity, and

the determination of certain constants of these substances for use

as standards in caloi'imetric work; (3) the determination of the ph.ysical properties of metals and alloys used in the arts demands a detailed knowledge of their chemical composition. The successful

carrying out of these researches will be of very great value to the

wide range of industries in which these i)roblems are of vital importance.

ENGINEERING INSTRUMENTS.

The demand of go\ernment departments and the public for information regarding engineering tests has greatly jncreased, and

many instruments have been submitted for test, including anemometers, speedometers, meter jirovers, water meters, paper testers, pres- sure gauges, steam valves, and the Avork was main]}- for jjracticing

engineers or municipalities. A small mei'cury manometer, Avith maximum capacity of GO pounds per s(}uare inch, has been erected for the

calibration of gauges of low range, and one of greater capacity will

be installed in the new building.

A study has been made of the eti'ects of air drag, surrounding walls,

wind currents, and centrifugal forces upon the present method of

testing anemometers. Tn this connection a new tripping and tiuiing

device has been develo])e(l so as to completely elimiiuite the personal

element of the operator. The ui)p('r limit of availal)le speed has
16 BEPORT OV DIRECTOK OF BUREAU OF STANDARDS.

been increased to 3,300 feet per minute, and the lower decreased to

about '200 feet per u)inute.

PROPERTIES OF MATERIALS.

The purpose of tliis branch of the liureau's work is tlie determination of the physical and chemical properties of materials in cases where definite authoritative information is needed in connection Avith

their purchase and sale or their use. As far as possible, this work is confined to investigational tests. Commercial tests are not made except for the departments of the

Government and for individuals where the facilities of private testing- laboratories are not available.

A study of a number of samples of brick was made, to determine

the best method of measuring the absorptive capacity and its influ- ence u^Don the adhesion between bricks and mortar. Apparatus has

been secured and an investigation is being made of lubricating oils,

for the purpose of determining the relation between their physical

and chemical properties and their value as lubricants. An investigation of twentj'-two bookbinding cloths has been made for the Printing Investigation Connnission, as a basis for the preparation of standard sj^ecifications for the binding used on public dociunents. Other

investigations of like nature are luider way or will be begun in the near future. This work Avill be greath- facilitated by the completion

of the new laboratory recently authorized by Congress.

The connnercial tests made for the departments of the Government

and others include cements, plasters, concrete, steels, alloys, bricks;

steam, air, and Avater hose ; valves and other fittings, textiles, jDaper,

inks, tAvine, etc. In many of these cases the tests Avere made not only

to ascertain Avhether or not they complied A\nth the specifications, but

Avith a vieAv to securing data for the purpose of improA'ing such specifications generally and the methods of testing.

PERSONNEL.

The personnel of the Bureau, including the Director, as i^rovided

by Congress, consists of 118 persons, classified as folloAvs:

Scientific force.—One physicist, 1 chemist, 6 associate jjhysicists.

1 associate chemist, 21 assistant physicists, 3 assistant chemists, 21

laboratory assistants, 6 aids, and 7 laboratory apprentices; total. 67.

Office and clerical force.—One secretai*y, 1 librarian, 9 clerks, 1 storekeeper, 1 draftsman, 2 assistant messengers, -t messenger boys:

total, 19.

Engineer and mechanical force.—One engineer, 4 assistant engineers, 1 electrician, 7 mechanicians. 1 AvoodAvorker, 3 skilled laborers,

3 firemen, 1 elevator boy, 4 laborers, 2 Avatchmen, 2 janitoi-s. 2 charwomen ; total, 31.
REPORT OF DTRECTOR OF BUREAU OF STANDARDS. 17

LIBRARY.

The technical library of the Bureau contains d:,561 bound volumes,

consisting, of works on physics, chemistry, mathematics, engineering,

and related fields. The librarj^ is classified b}' subjects and card

indexed b}^ author and subject. During the year 1,087 books were

added. The Bureau regularly receives 169 technical jDeriodicals. The

circulation of the library has been about 5.500, including 600 loaned

by other government libraries. Cooperation among the scientific

libraries in Washington has greatly extended the reference resources

for technical investigation.

PUBLICATIONS.

During the year 31 technical papers were published giving the re- sults of researches and investigations conducted by the Bureau.

Nineteen extra editions of earlier papers were required to meet the

public demand for the jDublications of the Bureau. The standard

specifications for the purchase of carbon-filament incandescent lamps

were published in revised form in Circular 13, and separately as a blank form for use in contracts for government purchases.

SUMMARY OF TESTS.

The work of the Bureau involves, among other things, a large

amount of testing of standards, measuring instruments, and materials. A certain amount of this work is already organized upon an

accurate routine basis. Much of it, however, involves investigation of

the scientific principles underl3dng the test, a study of existing methods, and the development of new standard tests of known accuracy.

In such cases the research which must precede the actual testing is

a most important function of the Bureau. For the test, a reasonable

fee is charged, except when made for the National or State Governments. The corresponding amounts for government testing are of

interest, however, and are added to the statement of tests which

follows

:

Number and Value of Tests CoiiPi-KTEi), Fiscal Year endku .June 30, li)OS.

For Government. For public. Total. Nature of test. Number. Value. Number. Value. Number. Value.

Length 187 $267. 55 95 $181.20 282 $448. 7.5 Mass 902 438. 75 489 269. 00 1,391 707. 76 Capacity

Temperature

2, 313 728. 20 517 356. 10 2, 830 1,084.30

1,359 603. 46 8, 830 1,788. 55 10, 189 2, 392. 01 Optical 1,286 1,309. 00 5 11.00 1,291 1, 320. Ol> Engineering 1,778 6, 582. 40 62 89.25 1,840 6, 671.65

Electrical 129 496. 85 248 765. 60 377 1 , 262. 45 Photometry 32 81.50 69 103.50 101 185.00 Chemical 1 , 844 7,181.02 431 706. 84 2, 275 7, 887. 8(i Miscellaneous .'")8 49. 35 60 63. 25 118 112.60

Total *. 9, 888 17,738.08 10, 806 4,334.29 20, 694 22, 072. 37
18 REPORT OF DIRECTOR OF BUREAU OF STANDARDS,

The receipts for tests were as follows

:

Total receipts, 1907-8 $4,375.77

lieceivecl prior to July l', 1907, for tests completed in fiscal year 1907-8 58. 30

$4, 434. 07

lieceived for tests in progress at close of fiscal year 1907-8 99. 78

Fees for tests completed, 1907-8 4, 334. 29

FINANCIAL STATEMENT.

The following statement shows the amount and object of each

iipj)ropriation provided for the Bureau for the fiscal year 1908. the

disbursement during the year, the amount of unfilled and unpaid

orders at the close of the year, and the unexpended balance remaining

at the close of business June 30. 1908

:

Appropriation. Total appropriation. Disburse- ment. Liability. Balance.

$1.30, 620. 00 41,000.00

15, 000. 00

3, 000. 00

$123, 874. 24 30,665.93

13, 099. 63

2, 982. 86

86, 745. 76

634. 32

136. 8.T 17.14

Equipment $9, 699. 75 1,763.52 Grounds

Total 189, 620. 00 170, 622. 66 11,463.27 7, 534. 07

The following statement shows the condition of the appropriations

for the preceding two fiscal years at the close of business June 30,

1908

:

1906. ! 1907.

I Appropriation. Total appropriation.

Disburse- ment.Liability. Balance.

Total appropriation.

Disburse- ment.Liability. Bal- ance.

Siilarie.s $99, 660. 00 41,000.00

12, 500. 00

1, 500. 00 12,484.10

$95, 727. 45

40, 927. 61

11, 893. .51

1, 499. 37

12, 472. 09

$3, 932. 55 2.91

606. 49

.03 12.01

$111,440.00

41,000. 00

15, 000. 00

3, 000. 00

$108, 399. 59

40, 41.5. 03

14,996. 35

3,000. 00

$3, 040. 41 90.24 General expenses . 3.65

.

Grounds

$69. 48 $494. 73

Total '.. 167, 144. 10 162, 520. 03 69.48 4, 554. 59 170,440.00 166,810. 97 494.73 3,134.30

BUILDINGS AND GROUNDS.

EHiring the year Coiigre.ss jjrovided for a new building to furnish

laboratory space urgently needed by the Bureau. Plans in harmony

with the existing buildings will be completed as soon as possible and

the contract will be let early in the autumn. The new building will

materially relieve the congestion in several lines of work.

The grading of the grounds has been continued along the lines

previously laid out. The .steep slope south of the main building has

been partly filled in up to grade and seeded with lawn grass. The
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 19

easit portion of the gTOunds has also been graded and put in excellent

condition.

INSTRUMENT SHOP.

The apparatus used by the Bureau is largely special in character,

designed by the experts who are to use it in their woi'k and constructed under their direct supervision. The quality and quantity

of testing and research depend to a large degree upon the facilities

available for constructing such apparatus. The instrument shop of

the Bureau is well equipped with skilled mechanicians and modern

machine tools, and has materially aided the Bureau in maintaining

a high standard in its technical work.

Respectfully, S. W. Stratton,

Director.

To Hon. Osc ar S. Straus,

Secretary of Conitnrrcc niul Lahor.

O