Annual Report

of th»

Director of the Bureau of Standards

to the

Secretary of Commerce and Labor

for the

Fiscal Year Ended June 30, 1906

Washington

Government Printing Office

1906

Annual Report

of the

Director of the Bureau of Standards

to the

Secretary of Commerce and Labor

for the

Fiscal Year Ended June 30, 1906

Washington

Government Printing Office

1906
Department of Commerce and Labor

Document No. 74

bureau of standards
REPORT

OF THE

DIRECTOR OF THE BUREAU OF STANDARDS.

Department of Commerce and Labor,

Bureau of Standards,

Washington, July i, 1906.

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, 1906:

ELECTRICAL WORK.

The electrical division of the Bureau is divided into five principal

sections. The first has to do with resistance and electromotive force,

the second with inductance and capacit\' , the third with magnetism,

the fourth with a wide range of electrical measuring instruments, and

the fifth with photometr}7

.

ELECTRICAL RESISTANCE AND ELECTROMOTIVE FORCE.

The work of this section includes the construction and verification

of standards of electrical resistance and of electromotive force, the

calibration of resistance boxes, Wheatstone bridges, potentiometers,

and other resistance apparatus, the verification of resistance standards

for current measurement, and the determination of the electrical

conductivity, temperature coefficient, and thermoelectric power of

materials.

The installation of the greater portion of the permanent equipment,\

especially designed to facilitate and expedite the routine testing of

this section, has been completed. The standards of a number of manufacturers of electrical apparatus have been verified or reverified, the

conductivity standards of several manufacturers of copper wire have

been submitted for certification, and a large amount of testing has been

done for other bureaus of the Government and for the public.

In conjunction with the chemical division, considerable progress lias been made on the problems relating to the standard cell. A large

number of cells set up with materials prepared by various methods

3
4 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

have been kept under observation in electrically controlled thermostatic

baths, and the results indicate that they ma}7 be reproduced with a high order of accuracy.

Some progress has been made on the problem of the primary mercurial resistance standard in the construction of special comparing

apparatus. A room will be fitted up so that measurements, as far as

possible, can be made at 0° C, in accordance with the recommendation

of the Berlin International Electrical Conference.

INDUCTANCE AND CAPACITY AND ABSOLUTE MEASUREMENTS.

This work includes the investigation of methods of inductance and

capacity measurement, the construction and testing of standards of

inductance and capacity for the Bureau, the testing of such standards

for the public, and the measurement of' the inductance and capacity

instruments. Several important improvements have been made during the year in the accurate measurements of inductance and capacity,

some of which have been described in the Bulletin of the Bureau.

The standards of the Bureau have been further studied and their

temperature coefficients investigated. The investigation which has

for its object the determination of the ratio of the electromagnetic to

the electrostatic units of electrical measure has been continued through

the year, and results which are of much greater accuracy than have

ever before been obtained have justified the large amount of work

that has been expended upon this fundamental problem. The investigation will be described in forthcoming numbers of the Bulletin.

Condensers and inductance have been tested for educational institutions and the Government, including standards of capacity and induct- ance and instruments emploj^ed in wireless telegraph work.

MAGNETISM.

The work of this section has been unavoidably delayed by necessary

changes in the personnel of the section. The development of the work

will now be taken up and the Bureau will soon be in a position to do

such magnetic testing as it is likely to be called upon to do.

ELECTRICAL MEASURING INSTRUMENTS.

In this section is carried on the investigation, and construction when

necessary, of instruments of precision for measuring electrical current,

electromotive force and power, and the phase, wave form, and frequency

of alternating currents; also the testing of laboratory and commercial

ammeters, voltmeters, wattmeters, watt-hour meters, phase meters, curve tracers, and other instruments used in connection with alternating currents. Several investigations have been made in connection

with electrical measuring instruments, and a considerable amount of

testing has been done.

During the year a considerable amouiit of apparatus has been added
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 5

and the facilities and conveniences of the laboratory increased by

further wiring and switch-board connections. A. special hot and cold

room for use in measuring temperature coefficients has been built and

considerable progress made in building a large rheostat and controlling

switch for the 10,000-ampere battery used in heavy current testing.

A new form of potentiometer has been designed and built, and some

of the new alternating current measuring instruments previously built

have been thoroughly studied.

The harmonic alternator, especially designed and built for the work

of this section, has been received and will soon be ready for use.

PHOTOMETRY.

During the }

7 ear much progress has been made, both in photometric

testing and in photometric investigation. A considerable number of

incandescent lamps for use as secondary photometric standards have

been standardized, including 50 such lamps to be used as standards at

the various testing stations of the Navy Department. In addition,

the demand for commercial testing of electric lamps for different Government Departments has developed so rapidly that the equipment

recently installed for this work has alreadj' become inadequate, and

additions will have to be made during the coming year.

Besides the tests on electric lamps, a study of the relative illuminating powers of a number of samples of oil was undertaken at the

request of the Bureau of Corporations of this Department.

During the year a comparison of the photometric unit of the United

States with the units of England, France, and German}- was undertaken, and preliminaiw steps were taken leading to a stud}- of the

question of primary standards of luminous intensity.

Apart from the testing of lamps and the study of photometric standards, it is the function of the section of photometry to pursue original

investigation with a view to improving the methods of photometiy.

To this end an investigation of the rotating sectored disk, which was

begun last .year, was pursued further and completed during the present year, rendering possible the use of the rotating sector in the most

accurate photometric measurements. Moreover, by the application of

the sectored disk to commercial photometry, a saving of time has been

effected and higher accuracy attained in this branch of the work.

The commercial photometer has been improved during the year by

the addition of several new instruments, designed and constructed at the Bureau to'meet the special needs of the work.

WEIGHTS AND MEASURES.

WEIGHTS.

The recomparison of the standards of mass, begun last year, was

only partially completed, owing to the unusual amount of routine test- ing. A complete calibration has been made of the set of secondary
6 REPORT OF DIRECTOR OP BUREAU OF STANDARDS.

gold-plated standards, and it is expected that during the coming year

the new set of platinum-indium weights from 500 grams to 1 milligram

will be intercompared and their values determined by direct comparison

with the national prototype kilogram.

I """"The effort on the part of the Bureau to improve the character of

precision weights made in this country has been successful. They are now made in accordance with the specifications of the Bureau, and are equal to those made by the best European manufacturers. The circular recently issued, giving information as to the construction of

weights, will lead to further improvement in their construction. There

is an urgent and constant demand from manufacturers, State and city

^sealers, and scientific laboratories for weights bearing the seal of the

Bureau.

The Bureau has adopted three classifications for weights, namety, A,

B, and (J, the classification depending upon their form, material, and

adjustment.

Experiments have been made as to the effect of condensation of

moisture on the surface of lacquered weights and will be continued

during the coming year. This effect was found to be much greater than

was anticipated, amounting to as much as one-tenth of a milligram in

50 grams.

MEASURES OF LENGTH.

The usual variety of length comparisons were made, including sur- veyors' and engineers' tapes, standard yards and meters, subdivided

scales, plug gauges, deflection and inertia bars for magnetometers,

and a number of special end standards. Satisfactor}^ progress was

made on the 50-meter comparator for geodetic standards and the

50-meter bench standard for tapes, "both of which are installed in the

tunnel connecting the physical and mechanical laboratories. In March

the Coast arid Geodetic Survey submitted a number of nickel steel

(Invar) tapes which were needed for immediate use in the measure- ment of a number of primary base lines. In order to secure the

range of temperature likely to be met with in the field, it was necessaiy

to install a system of pipes through which cold brine may be pumped.

B}' this means and by the introduction of hot air into the tunnel the

temperature was varied from about +2° to +28° C.

The geodetic comparator, which will later be described in detail,

consists of 11 stone piers, 5 meters apart, on which are mounted-microscopes susceptible of adjustment in the vertical and horizontal direction. The distance between the microscopes is measured by means of a 5-meter bar, packed in ice to control its temperature, the bar and

its ice trough being moved parallel to a line connecting the piers.

On account of the change in the distance beween the terminal marks,

caused by the expansion and contraction of the whole tunnel when the

temperature was raised and lowered, it is difficult to determine how
REPORT OP DIRECTOR OP BUREAU OP STANDARDS. 7

accurately the distance between the terminal marks, 50 meters apart, can be determined, but there seems to be good evidence, based upon

consecutive measures made about thirty minutes apart, that the probable error does not exceed 1 part in 5,000,000—a quantit}^ far within

that required.

Nonexpansible steel tapes are of recent construction, hence their

behavior under working conditions is of considerable interest to the

engineering profession. From the results obtained after repeated

reeling and unreeling of the tapes and exposures to changes of temperature there is every reason to believe that their use in base-line

measurement will increase the accuracy of such work and decrease the

cost. The determination of the constants of the Coast and Geodetic Survey

tapes involved, also, a redetermination of the length of the 5-meter

standards belonging to the Survey.

The construction of the 50-meter (150 feet) bench standard, mentioned in the last report, was completed in May, but it remains to be

graduated. It was found impossible to get a bar of the required

length, hence it became necessary to make the bar of shorter sections.

After investigating the Goldschmidt thermit process, a number of cold

rolled steel bars about 35 feet in length were purchased and welded

together to form a bar slightly over 50 meters in length. The welding

was entirely successful, resulting in a bar which is practically homogeneous and of the desired length.

The construction of the 1-meter comparator, though urgently

needed, could not be taken up on account of the delay in securing a nonexpansible nickel steel I-beam, the essential feature of the proposed comparator. This material can be secured only in France, and

great difficulty is met with in rolling it into beams of sufficient size.

The microscope and piers are on hand and the necessary plans for the

comparator are well under way. It will be designed to vary the temperature between 0° and 100° C and to maintain it constant at any

temperature between the above limits by thermostatic regulation.

When completed it is proposed to redetermine the relative lengths and

absolute expansions of the national prototype meter and the secondary

standards of the Bureau.

During the year a 50-foot bench standard installed in connection

with the State sealer's office in the statehouse, Boston, Mass., was

graduated by the Bureau, the necessary expenses being paid by the

State of Massachusetts. The comparator, which was designed by the

Bureau and partly constructed under its supervision, now forms a

valuable addition to the equipment of the State sealer's office.

The comparator for end standards mentioned in the report of last

year has been used with success during the year and proved to be all that was expected when it was designed. Lack of opportunity has
8 REPORT OF DIRECTOK OF BUREAU OF STANDARDS.

prevented a thorough investigation of the comparator, but a sufficient

test was made to demonstrate that accurate results may be readily

obtained.

A subdivided meter of the highest grade is urgently needed in this

division, and steps have been taken to secure one of the platinumiridium meters from the French Government, made of what is known

as the ""alloy of 1874." These bars were prepared by the French sec- tion of the International Committee on Weights and Measures, but

were rejected by the International Committee because the impurities

slightly exceeded those specified. Nevertheless four of those bars were

made up and included in the comparison of the various national prototype meters, and proved to be in every way as satisfactory as those

made from the material finally selected by the international committee.

The bars in the present state are not subdivided, but if one is secured

it could be graduated and afterwards sent to the International Bureau

for calibration.

An Abbe Fizeau dilatometer for the determination of the expansion

of small samples of metals will be added to our equipment, either by

purchase or b}r construction in the shop of the Bureau.

VOL VMETRIC APPARA TVS. The greater proportion of the volumetric apparatus submitted for

testing has come from the various laboratories of the Government

Departments. Practically all apparatus of this character is purchased

according to the specifications of this Bureau, and is submitted for

test before acceptance by the Government.

There has been an earnest effort on the part of manufacturers of

volumetric apparatus to comply with the requirements of the Bureau,

and the effect of these regulations is already evident in the superiority

of the apparatus now submitted over that formerly supplied on Government contracts. In order to assist manufacturers in improving the

quality of the apparatus made b}7 them, this Bureau has frequently

undertaken the graduation of their standards; and in cases where

important investigations have required apparatus more accurate than

ordinarily made the graduation has been undertaken by the Bureau.

Among these special cases may be mentioned measuring flasks for

research work in sugar analysis and pipettes for the standardization

of antitoxins. The apparatus designed at the Bureau for testing volumetric apparatus has been subjected to the practical test of routine

work with 'practical results, and if the Bureau had the necessary assist- ance the demands for tests of this character could be promptly met.

HYDROMETERS.

The testing of hydrometers for various purposes has made good

progress. This work has been done to a limited extent for a number

of 3

7 ears, but within the past }'ear it has reached a stage where it
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 9

becomes necessary to make a systematic study of the methods of

hydrometry, including the investigation of the surface tensions of the

liquids used in this work.

BAROMETERS.

A number of aneroid barometers have been submitted for examination and approval by different bureaus of the Government and by the

public. This work is now done with an apparatus purchased from

abroad, but which is inadequate. It is proposed to construct apparatus

large enough to accommodate a greater number of instruments, and

provide facilities for determining the effect of temperature on their

readings.

MEASUREMENT OF TIME.

The Bureau continues to receive the noon signal from the United

States Naval Observatory by wireless telegraphy, as mentioned in the

previous report, and the standard Riefier clock, although exposed to

considerable variations of temperature, furnished satisfactory time

for Bureau purposes. The cabinet for testing watches in various

positions has been completed, and a room, the temperature of which

may be varied, is being fitted up for this purpose. Plans have also

been prepared for converting a small room in the basement into a constant temperature clock room.

WEIGHTS AND 3IEASURES CONFERENCE.

The second annual meeting of the State sealers of weights and measures was held on April 12 and 13. The attendance and the interest

displayed in the questions discussed were greater than at the first

meeting. It was decided to form a permanent organization of State

officials and others interested in weights and measures to hold an

annual meeting for the purpose of discussing matters pertaining to

the testing and sealing of commercial weights and measures throughout the country and to aid in securing the adoption of uniform laws

in this regard. It was the general opinion of all present that if possible national legislation should be enacted relative to these questions.

In order to secure the proper cooperation between the States and the

Bureau, the Director of the Bureau was elected chairman and the

chief of the weights and measures division of the Bureau was made

the permanent secretary of the association. It was decided that at

the next meeting a model law, to be prepared by the executive committee, should be presented for discussion. The effect of this organization toward bringing about much-needed reforms in the laws and

practices concerning weights and measures will be very far-reaching.

232b—07 2
10 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

THERMOMETRY, PYROMETRY, AND HEAT MEASUREMENTS.

The work carried out in this division during the year consisted in

the testing of some 11,660 thermometers of various kinds, such as calorimetric and Beckmann thermometers used in determination of the

calorific value of fuels, laboratory thermometers used for the precise

measurement of temperatures up to 500" C (930° F), clinical thermometers used by the medical profession, maxima and minima thermometers, industrial thermometers for controlling the temperatures of

technical processes, clinical standard thermometers used by manufacturers to control their product; also thermocouples, pyrometer-galvanometers, electrical resistance thermometers, and optical pyrometers for

the measurement and control of high temperatures in metallurgical

and other industrial operations and for special investigations in engineering laboratories. The calorific value of fuels has been determined

as a basis for the award of contracts or the fulfillment of specifications

for fuels furnished the Government. Tests have been made of the

physical properties of illuminating and lubricating oils and other combustible compounds—such as the determination of the flash points,

viscosities, setting points, etc. —and the testing of the thermal properties of glasses.

The results of an investigation of the methods of annealing high-temperature thermometers were published in Bulletin No. 2, Volume 2. This investigation called attention to the defects in high-temperature

mercurial thermometers and suggested proper methods of heat treat- ment to avoid these defects. The result has been a marked improvement in the l'ecent product submitted for test. The 11,132 clinical thermometers tested were submitted by manufacturers, dealers, hospitals, physicians, and the several medical departments of the Government. Seven and five-tenths per cent of the

clinical thermometers tested failed to pass the test requirements, in

comparison with 8.4 per cent for the j^ear preceding.

The intercomparison of the primaiw standard mercurial thermometers on which is based the standard scale of temperature in the interval

0° to 100° C—the interval in which the highest attainable precision in

temperature measurement may be realized—has been practically completed, and it is expected the results will be published in the near

future. Some new platinum resistance thermometers have been constructed, and a special Wheatstone bridge for platinum thermometer

work has been provided with suitable accessories, such as thermostats,

stirrers, thermoelectric keys, etc., for the rapid and accurate intercomparison of resistance thermometers, work on which this division

is now engaged for the purpose of establishing the standard scale of

temperature in the interval 100° to 500° C, and in the interval from

.0° C down to the lowest attainable temperatures, which will soon be
REPORT OP DIRECTOR OP BUREAU OF STANDARDS. 11

available in connection with the liquid-air aud liquid-hydrogen plant

which is now practically installed.

The special calorimeter, cooling tank, differential resistance thermometers, and other apparatus required for the determination of the

specific heat of brine solutions, an important thermal constant to the

refrigeration industry, has been completed. The experimental work

will be continued at every available opportunity.

Investigations have been carried out during the year on the radiation from platinum and palladium, and determinations of their melting

points, important thermal constants in the higher pyrometric range,

have been made. This work will be completed and published in the near future. In connection with this work a method has been developed which is especially adapted to the determination of the melting

points of the rare elements concerning whose thermal constants practically no reliable data are at present available.

Progress has been made in a further study of radiation methods of

measuring very high temperatures. The first publications bearing on

this subject (Bull. No. 1, Vol. 1, p. 109; No. 2, Vol. 1, p. 189) have

directed wide-spread attention to these methods, and many industrial

plants, as well as engineering and research laboratories, are now applying them. In connection with this work a special investigation has

been made on the degree of realization of black-body radiation from

different kinds of radiators, a question fundamental to the stud}T of all radiation problems.

A large amount of work has been done in the standardization of a number of thermocouples belonging to the Bureau. The measure- ments were most satisfactorily carried- out with the aid of electric

furnaces and at the solidifying points of a number of pure metals.

On this work is based the standard scale of temperature in the interval

500° to 1,500° C. Comparisons with standard thermocouples that

have been tested at foreign testing bureaus show a most satisfactory

agreement at these high temperatures.

Consulting engineers, representatives of industrial plants and of

engineering laboratories, have visited the Bureau during the year for

the purpose of studying methods of high temperature measurement,

and observing the operation of the various types of pyrometers in use

in its laboratories.

As a result of the investigations carried out at the Bureau directing

attention to the requirements of the industries in temperature meas- urement, several manufacturers have already, after consultation with

the Bureau, brought out improved apparatus designed to meet these

requirements. The information the Bureau has been able to place at

the disposal of American manufacturers and engineers is an important

feature of the work of this section.
12 .REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

It is of the utmost importance that the work relating to the intercomparison of the platinum resistance thermometers and the comparison of these with the primary standard mercurial thermometers be

completed as early as possible, as the standard scale of temperature

in use at the Bureau for the interval 100° to 500° C is based on this

investigation. The Bureau is receiving many requests from engineering and scientific laboratories for temperature standards within this

interval, in which the highest accuracy that is at present attainable in

temperature measurement is of the utmost importance.

The importance of controlling temperatures in so many industrial

operations and the demands of the recently developed electrochemical

industries for the measurement of temperatures make it imperative

that investigations should be carried out which would place at the

disposal of the engineer and the investigator essential information as

to the best methods of measuring these high temperatures.

As the gas thermometer is the fundamental standard of all temperature measurements, and as little reliable information is available con- cerning the gas scale of temperature above 1,150° C, it is especially

desirable that a gas thermometer be constructed adapted to work at

the highest temperatures to which this method is applicable, and that

the scale which it defines be compared with the temperature scale

obtained by other methods.

The facilities now available in the way of liquid air, liquid hydrogen,

compressed gases, electrical energy, and apparatus especially designed

for the measurement of small temperature differences with the highest

attainable accura'cy, imposes upon the Bureau the imperative duty of

repeating and extending the -classical experiments of Thomson and

Joule on the expansion of gases, work which is fundamental to the

whole conception of temperature.

The great demand for the testing of all kinds of temperature-measuring instruments has seriously retarded the progress of important

investigations in this section, and it will be necessary to provide additional assistance at the earliest possible moment.

OPTICS.

While the work of this division consists chiefly in the determination

of the properties of materials, physical laws, and constants, considerable testing has been done in polarimetry and a few in spectroscop}^;

investigations have been undertaken in connection with the application

of interference methods to the measurement of length.

POLARIMETRY.

During the year special attention has been .given to the work of

clearing up certain doubtful points involved in the testing of raw

sugars, both for the collection of duties by the Government and com-
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 13

mercial transactions. In order to accomplish this several theoretical

problems have been undertaken, among- which may be mentioned (1) a determination of the light source best suited as a standard; (2) the

elimination of errors due to the clarifying reagent used in testing;

and (3) the determination of the 100° Ventzke point on the saccharimeter scale. Much time has been spent in the perfecting of apparatus

for the rapid and accurate testing of quartz control plates, necessitating an investigation of suitable monochromatic light sources. The

work of eliminating the errors in the comparative daily exchange

samples of sugar tested for the Treasury Department has been con- tinued with good results.

SPECTROSCOPY.

The spectroscopic work of the Bureau has been directed toward the

determination of the purity and intensity of sources of monochromatic

light. The relation between the luminous-intensity and energy intensity of radiation has been carefully investigated and applications made

to monochromatic radiation. Many spectrum lines from different sources under different conditions have been examined in detail with

an echelon grating and their structure and ratio of width to intensity

recorded.

Four classes of requirements for monochromatic sources of light

have been recognized and provided for:

1. Polarimetry requires sources of the highest possible intensity

but of only moderate purity. The effect of both purity and intensity on polarimetric sensibility and accurac}' was investigated theoretically

and the most advantageous available light source determined.

2. Interferometry, as applied to measurements of length and angle,

requires a high degree of purity but a moderate intensity. Limiting

requirements were investigated and available monochromatic sources adapted to these requirements were determined.

3. Reference standard wave lengths require high purity and moderate intensity. Some attention was given to this field during the year;

however, several thoroughly competent investigators have taken up

the matter elsewhere.

4. Absolute length standards require the highest attainable purity

with moderate intensity. The impurity should not exceed 1 part in

10,000,000. A source of this degree of purity was found and is beinginvestigated.

RADIOMETSY'.

During the past year an investigation of infra-red absorption and

reflection spectra was undertaken and completed. The work included an examination of two classes of crystals, by a method which was

developed from known facts concerning the selective absorption of

heat rays. By this method it was shown that in one class of crystals

the water content is pi'esent as water, while in the second class the
14 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

constituents of water are not present as such, but are chemically combined with other atoms.

A determination was made of the absolute reflecting power .of a number of metals, which heretofore have not been examined.

1 A preliminary examination of the infra-red selective reflection of solids in

solution was made. The results obtained show that the method is feasible, and that the reflection spectrum of the solid may or m&y not

be the same as when in solution. The field is entirely new and

deserves further investigation.

A sensitive galvanometer, a bolometer, wire gratings, polarizing

apparatus, and other accessories needed in infra-red radiometric work

have been constructed in the instrument shop. Rock salt and sylvite

prisms have been purchased, so that within a short time the equipment

for this class of measurement will be fairly complete.

An investigation is in progress of the different types of instruments

for measuring radiant energy, including the bolometer, radiometer,

radio-micrometer, and thermopile. This includes also the development

of a new instrument which is a combination of the radiometer and the

radio-micrometer. A stud}T of the radio-micrometer has shown that

the weight of the moving coil can be reduced to at least one-third the

weight of those previously described, while its sensitiveness is increased

by at least 70 per cent by placing it in a vacuum.

CHEMISTRY.

During the year the samples of standardized irons, which have heretofore been distributed by the American Foundrymen's Association,

were carefully analyzed at the Bureau, and in January the stock of

those samples remaining in the hands of the association was turned over to the Bureau and since that time the}7 have been distributed to

parties desiring them.

One sample of standardized steel has also been prepared and is furnished in a similar manner, while arrangements have been partially

completed for the preparation of a whole set of such standards.

A zinc ore, a sulphide ore, and a sample of bearing metal, which have

been distributed by the different societies for the purpose of improving

methods of technical analysis, have been carefully analyzed in this

laboratory.

A considerable amount of work has been done in conjunction with

the electrical division in the preparation and examination of pure

mate] ial to be used in the construction of Clark and Weston standard

cells. A study of the standards of purity for chemical reagents and of the

methods to be used for the quantitative determination of small amounts

of impurities in such reagents has been undertaken.

A new determination of the exact quantitative relation between

hydrogen and oxygen in water is in progress.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 15

A number of substances have been examined for this Department

partly in connection with contracts for purchases and partly in connection with investigations of the sale of commercial products which

are being made by the Department.

ENGINEERING INSTRUMENTS AND MATERIALS.

This section is equipped to conduct tests of water meters not larger

than 2 inches, gas meters and gas-meter provers, speed indicators,

pressure and vacuum gauges, anemometers, and of paper, twine, and

cloth. A lai'ge mercury manometer is now in the course of construction for the direct comparison of accurate pressure gauges and their

study under varying conditions of temperature, pressure, and stability.

The demands upon the section for the testing of engineering materials

have increased very much during the year. A limited amount of

cement and concrete testing has been done for Government Departments and for the District of Columbia. Numerous cases of dispute

regarding the quality of construction materials, such as iron, steel,

brick, stone, cement, concrete, etc., have been referred to the Bureau

for a determination of the physical properties in question.

The section is prepared to make extension, compression, and trans- verse tests on metals, to a total load of 100,000 pounds; to determine

tensile and compressive strength, specific gravity and time of set of

cement and cement mortars. The rapidly increasing use of concrete

in construction work, especially in the form of hollow blocks, has developed a great need for the careful, independent, and exhaustive study

of the thermal conductivit}T and the effects of temperature—more

especially high temperature—upon the compressive strength, expansion, and durability of all kinds of concrete aggregate.

The use of concrete has developed a great activity in the production of high-grade building brick which shall -be able to compete with

it in compressive strength and durability. Requests for this kind of

information are frequentlv referred to the Bureau and it is important

that data be secured for the use of building inspectors and engineers.

A special testing machine of large capacity is needed for this work in

order that tests commensurate with actual working conditions may be

undertaken.

There are in this country no uniform methods or apparatus for the

testing of wood, paper, textile fabrics, inks, mucilage, etc. The development of standard methods and apparatus for this purpose, and the

careful calibration of such apparatus for the Government Departments, large consumers, and manufacturers is an important work the

Bureau ought to do.

The development of standard methods and apparatus for the testing

of lubricating oils, oils used in the arts, resins, varnish, protective

coatings, glue, etc., is also very important.
16 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

In order that this section may undertake the development of such

standard methods and apparatus for the testing of the important

materials of commerce, and assist in engineering researches which

have a wide industrial significance, it is desired that additional space

be provided by the erection, at an early date, of a building for this

purpose.

PERSONNEL.

The personnel of the Bureau may be classed in three groups. The

first has to do with the scientific work of the Bureau, the second with

the office and clerical work, and the third with the operation of the

mechanical plant, the construction of apparatus, and the care of the

buildings and grounds. The plan of organization in each of these

groups involves a regular graduation of salaries, in order that faithful

and efficient service ma}'' be rewarded by promotion when vacancies

occur. In recommending persons for appointment to the staff of the Bureau

every precaution is taken to insure that they possess the proper qualifications for the work in hand and the fundamental education or training necessary for advancement in the service]

The staff of the Bureau, including the Director, consists of 87 persons, distributed as follows:

Scientific force. —One physicist, 1 chemist, 4 associate physicists, 1

associate chemist, 9 assistant physicists, 2 assistant chemists, 16 laboratory assistants, 1 computer, 4 aids, and 6 laboratory apprentices;

total, 45.

Office and clerical force. —One secretary, 1 librarian. 6 clerks, 1 storekeeper, 1 draftsman, 2 assistant messengers, 3 messenger boys;

total, 15.

Engineer and mechanicalforce. —One engineer, 3 assistant engineers,

1 electrician, 6 mechanicians, 1 woodworker, 2 skilled laborers, 3 fire- men, 1 elevator boy, 3 laborers, 2 watchmen, 1 janitor, and 2 charwomen; total, 26.

LIBRARY.

The library has been increased during the year by the addition of

713 volumes, in addition to numerous reprints and miscellaneous

reports. These books are of a technical character, covering the work

of the Bureau and subjects closely related to it. The Bureau receives by subscription or exchange 118 scientific periodicals and proceedings of learned societies, and has received gratis

many reports, translations, and- bulletins from similar scientific institutions, universities, and learned societies. During the year 543

volumes, consisting mostly of this material and completed volumes of

scientific journals, have been received and bound.

Purchases have been confined principally to books not available in

other libraries of the city, or in such constant demand as to require
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 17

copies immediate!}7 at hand. The privileges of nearly all of the libraries of the city have been extended to the Bureau. Many books have

been borrowed from them during the year, and much assistance has

been rendered by the several librarians. The library has a complete

author-and-subject catalogue of the works on hand. Through the card

distribution of the Library of Congress the Bureau is enabled to complete its author-and-subject catalogue of the library collection as far as cards are printed on subjects relating to the work of the Bureau.

PUBLICATIONS.

The following publications were issued by the Bureau during the

year:

Circular No. 3, concerning the verification of standards of mass.

Circular No. 9 (revised edition), regarding the testing and use of

glass volumetric apparatus.

Circular No 11, regarding the preparation and distribution of standardized samples of iron and steel.

The results of the scientific work of the Bureau are published in the

form of bulletins, two of which were issued during the year.

A new edition of the table of equivalents between the metric and

customar}7 weights and measures has been issued.

A pamphlet describing the international metric system of weights

and measures was issued in response to the demand for information

upon this subject.

The report of the proceedings of the first conference on the weights

and measures of the United States was also issued.

SUMMARY OF TESTS.

In connection with the work of the Bureau a certain amount of test- ing of standards and standard measuring instruments is done. The

tests completed during the fiscal year are shown in the following table.

In case the testing is done for parties other than the Government, fees are charged as provided for hy law. For comparison, the corresponding amounts are also indicated for Government tests.

Number and Value of Tests Completed during Fiscal Year ended June 30, 1906.

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

Length 181 $342. 20 78 S134. 90 259 $477. 10 Mass 238 133. 25 440 254. 60 678 387.85

923 261.80 11 10. 25 934 272. 05 Temperature 1,983 584. 00 9, 207 1,415.81 11,190 1.999.81 Optical 1,042 1,042.00 1 5. 00 1,043 1,047.00 Engineering 403 1,748. 00 25 40.00 428 1, 788.00 Electrical 120 445. 00 157 407. 45 277 852. 45 Photometry 1,130 344. 30 42 47. 50 1,172 391.80 Chemical 64 216.00 208 348. 85 272 564. 85 Sundries 158 121.50 186 176. 00 344 297. 50

Total 6. 242 5, 238. 05 10, 355 2. 840. 36 16,597 S, 078. 41
18 REPORT OF D [RECTOR OF BUREAU OF STANDARDS.

The receipts for tests were as follows :

Total receipts 1905-6 $3, 055. 81 Previously received for tests in progress 1905-6 162. 75 Due for outstanding tests 38. 23

100.98

53, 156. 79

Received for tests completed 1904-5 18. 75 Received for tests in progress 297. 68

316. 43

. Fees for tests completed 1905-6 2, 840. 36

FINANCIAL STATEMENT.

The following statement shows the amount and object of each appropriation provided for the Bureau for the fiscal year 1906, the disbursements during- the year, the amount of unfilled and unpaid orders at

the close of the }

r ear, and the unexpended balance remaining- at the

close of business June 30, 1906:

APPROPRIATIONS. 1906.

Fiscal year ended, June 30, 1906.

Appropriation. Total appropriation. Disbursement. Liability. Balance.

Salaries Equipment

Grounds

$99, 660. 00

41, 000. 00

12, 500. 00 1,500.00

12, 484. 10

$95,723. 45

31, 303. 56

10, 640. 83

1,499. 37

12, 324. 50

$4.00

9, 507. 55

1,612. 03

$3, 932. 55

188. 89

247. 14 .63 Outbuildings 27. 91

Total

131. 69

167, 144. 10 151,491.71 11,255.27 4, 397. 12

The following statement shows the condition of the appropriations

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

1906:

APPROPRIATIONS, 1904.

Fiscal year ended June 30, 1901,.

Appropriation. Total appropriation. Disbursement. Liability. Balance.

$74, 700. 00 110,000.00

10, 825. 33

500. 00

$69, 754. 59

109, 891 . 65

10, 722. 79

500. 00

$4,946.41

108. 35

102. 54 EquipmentGeneral expenses Grounds

Total. : 196, 025. 33 190, 869. 03 5, 156. 30

APPROPRIATIONS, 1905.

Fiscal year ended June SO, 1905.

$85, 780. 00

78, 500. 00

13, 250. 00

1,000. 00

15. 90

$83, 932. 44 78.370.74

13,141.11 1,000.00

15. 90

$1,847. 56

79. 26

78. 64 Equipment

General expenses Grounds

$50. 00 30.25

Outbuildings

Total 178, 545. 90 176, 460. 19 80. 25 2, 005. 46
REPORT OF DIRECTOR OE BUREAU OF STANDARDS. 19

INSTRUMENT SHOP.

The character and quantit}* of the work done at the Bureau is

influenced largely by the facilities possessed for the construction of

the special apparatus involved in all investigations. In every branch

of testing, new and improved apparatus must be designed and constructed in order to increase the accuracy or reduce the cost. The

instrument shop, while well equipped with machines and provided

with several excellent workmen, can not meet the demands of the

Bureau for its service. It is exceeding^ important that several additional mechanicians be secured, one of whom should be a glass blower

skilled in the construction of scientific apparatus.

BUILDINGS AND GROUNDS.

The small laboratory building designed for the work in low temperature, liquification of gases, and high pressure has been completed and

much of the apparatus installed. This building is of substantial, fireproof construction and conforms with the others as to stjde and general appearance.

A few minor repairs and alterations were made to the buildings during the year, including the construction of a small tunnel under the

west area of the mechanical laboratory which furnishes the means for

running pipes and wires to the low temperature laboratoiy. The work

of installing special piping, wiring, and plumbing in the several laboratories has progressed well during the year, but a considerable amount

of this work remains to be done. The portion of the ground lying

between the physical laboratory and the mechanical laboratoiy has

been graded. ' The steam and electric plant which furnishes heat, light, and power

for the buildings and for laborator}- use is no longer adequate for that

purpose, and during the past year it has been necessary to keep it in

operation during the greater part of the da}\ During the coming*

year it will be necessary to operate it continuousl}* throughout the

entire day of twenty-four hours. This will require some additional

equipment and assistance in the engineering force.

Respectfully,

S. W. Stratton, Director.

The Secretary of Commerce and Labor.

O