ANNUAL REPORT

I DIRECTOR Hill

BUREAU OF STANDARDS

SECRETARY OF COMMERCE

FISCAL YEAR ENDED JUNE 30, 1914

WASHINGTON

GOVERNMENT PRINTING OFFICE

IpI ' life"- , ion , SB

ANNUAL REPORT

OF THE

DIRECTOR

BUREAU OF STANDARDS

TO THE

SECRETARY OF COMMERCE

FOR THE

FISCAL YEAR ENDED JUNE 30, 1914

WASHINGTON

GOVERNMENT PRINTING OFFICE

1914

CONTENTS.

Page.

I. Functions, organization, and location 9

1. Standards of measurement 9

2. Physical constants 10

3. Standards of quality JO

4. Standards of performance 11

5. Relation of the Bureau's work to the public 13

6. Organization 14

7. Location 15

II. Scientific and technical divisions 16

1. Weights and measures 16 Weights 16

Capacity measures 16 Inspection of scales 17 Cement sieve testing 17 Time... 17 Gas-meter testing 17 Volumetric glassware 18

Expansion of materials 18

Barometry . 19

Track scale testing equipment 19

Assistance to Porto Rico 20

Weights and measures conference 21 Legislation 21 Publications 22

2. Thermometry, pyrometry, and heat measurements 22 Calorimetric resistance thermometers 22 Melting points of the refractory elements 23

Melting points of some refractory oxides 23

The monochromatic and total emissivity of nickel oxide (NiO)

in the range 600° to 1,300° C 23

The specific heat of copper 24 Latent heat of fusion of ice 1 24

Industrial gas calorimetry 24 Standard methods of gas testing 25

Combustion calorimetry and the heats of combustion of cane

sugar, benzoic acid, and naphthalene 25

Cold-junction correction for thermocouples 25

Ocean temperatures in the vicinity of icebergs and in other

parts of the ocean 26

Refrigeration constants 27 Heats of combustion gases 27 Resistance thermometry 28

Heat capacity of water and the mechanical equivalent of heat. . 28

Radiation pyrometers 28

Radiating properties of metals and oxides 28

Behavior of base-metal thermocouples at high temperatures 29 The thermal conductivity of refractories at high temperatures. . 29

Industrial viscosimetry 29

Low-temperature laboratory 29

The fire-resisting properties of structural materials 29

Testing 30

Information furnished, reports, etc 32

New work, equipment, and personnel 33

Standard melting-point samples 33

New equipment 33

3
4 CONTENTS.

II. Scientific and technical divisions—Continued. Page.

3. Electricity. 34

Equipping new electrical laboratory 34

Fundamental electrical standards 34

Electric-measuring instruments 34

Transformer formulas 34

Potential transformers 34

Sensitive galvanometers 35

Vibration electrometer 35

High-frequency instruments 35

Decremeter for radiotelegraphy 35

The standardization of electric wave meters 35

Inductance, etc 35

Properties of dielectrics 36

The decrements of coupled circuits 36

Magnetism 36

Radium 36

Gas photometry 37

Color photometry 37 Effect of atmospheric conditions on flame standards 37

Electrical testing 37 Information furnished on electrical subjects 38

Public-utility investigations 40

Service and standards for illuminating gas 40

Electrolysis mitigation 41 Electric light and power service 43

Life hazard in electrical practice 43

Illuminating engineering 44

Radiotelegraphy research laboratory 45

Additional facilities needed 45

4. Optics 45

Determination of standard wave lengths 45

Spectroscopic testing 46

Standard samples of pure gases 46

Polarimetry 46

Conference of polarimetric experts 46

Influence of atmospheric conditions in the polarimetric testing

of sugars 47 Study of the basic lead acetates 47 Determination of the 100-degree point of the saccharimeter 47 Precision polariscope 47 Preparation of standard sugars 47 Supervision of the Customs Service sugar-testing laboratories. . . 48

Polariscopic testing 48

Interferometry 48

Expansion of materials due to temperature changes 48

Planeness and parallelism of surfaces 48

Determinations of the optic axes of crystals 48

Specification and measurement of color 49

Colorimetric testing 49

Information as to color specification and measurement 49

Colorblindness 50

Turbidimetry 50

Transparency, translucency, diffusion 50

Investigation and design of optical systems 50

Testing of optical systems 51 Refractive index 51

Testing of materials for refractive index 51 Radiometry 52

Standards of radiation 52

Stefan-Boltzmann constant 52

Absorption constants of quartz. 53

Radiometric testing " 53

5. Chemistry 53

Standard analyzed samples 53

Determination of carbon in steel 54

Standard methods for the analysis of steel 54
CONTENTS. 5

II. Scientific and technical divisions—Continued. Page.

5. Chemistry—Continued.

Preparation of electrolytic iron 54

Influence of gases, oxides, and slag on the quality of steel 55

Other investigations with reference to iron and steel 55 Cooperation on specifications for and analysis of nonferrous

metals and alloys 55 International cooperation on methods of analysis for pig and cast iron 55

Phosphate rock analysis and the determination of alumina 56

Determination of water in standard materials and in coal 56

New method for the determination of rubber 56

Iodine number of linseed oil and petroleum oils 56

Lubricating oils 57 Chemical researches on paper 57 Analysis of printing inks 57 Hydrogen electrode studies 57 Operation and regulation of electrocyping baths 57 Physicochemical researches on organic solvents 58

Other physicochemical researches 58

The determination of ammonia in illuminating gas 58

Pure ammonia for refrigeration constants 58

Study of gas-testing methods 58

A simple gasoline generator for sulphur determination 59

Preparation of secondary butter-color standards 59 Research on the methods and standards employed in volumetric analysis 59 Platinum investigation 59

Quality of chemical reagents 60

Oxidimetry 61 Additional chemical assistance 61 Chemical tests of materials 61 General paint investigation 61 Analysis of oil varnish 62

Corrosion of iron and steel 62

6. Metallurgy 62

The critical temperatures A2 and A3 of pure iron 62

Finishing temperatures of rails 63

Melting points of the elements 63

Total radiation from nickel oxide 63

Iron-carbon equilibrium diagram 64

Preparation of pure metals and alloys 64

Carbon in steels at high temperatures 65

Material for crucibles 65

Physical properties of pure iron 65

Standard test specimens • 66

Causes of failure of railway material 66 Fusible boiler plugs 67 Failure of manganese bronze 67

Thermoelectric method for determining the impurities in platinum 67

Nomenclature of alloys 67 Measurements with the micropyrometer 68

Method of sampling steel 68

Efficiency of surface conbustion furnace 68

Metallurgical testing 68

Metallurgical information 69

Publications 69

7. Structural, engineering, and miscellaneous materials 70 Structural steel column tests 70 Brick and concrete column tests - - 71 Failure of rails and railway material 71 Standard test specimen for cast bronze 71 Influence of time in testing steel specimens 71 Measurement of strains in engineering structures by means of the strain gauge 71 Wire cables 72 Calibration of testing machines 72
6 CONTENTS.

II. Scientific and technical divisions—Continued. Page.

7. Structural, engineering, and miscellaneous materials—Continued.

Information as to the strength of metals and alloys 72 Tests on the strength of materials 72 Hydration of Portland cement 73

Durability of concrete in alkali waters 73

High-pressure steam test of cement 74 Methods of determining the time of setting of cement 74 Standard cemsnt sieves 74 Standard specification for Portland cement , 75 Miscellaneous investigations of stone, cement, etc 75 Investigation of building stones 75 Effect of moisture and temperature changes on concrete 76 Granular analysis of cement 76 Durability of plasters and stuccos 76 Effect of sea water on concrete 77

Silica cements 77 Results of specification tests of Portland cement 77 "Variation of the physical properties of concrete 77 Cement inspection and testing . 77 Information furnished as to cement and concrete 78

Investigation of paving blocks 78

Study of white-ware glazes 78

Behavior of clay in water suspension 79

Viscosity of porcelain at kiln temperatures 79

Plasticity of clays 79 Suitability of American clays for vitreous ware 79 I Ceramic glazes 80

Drying properties of clays 80

Clay-shrinkage disks 80

Production of paving bricks from slag 80

Strength of refractory bodies 80

Effect of crystalline salts upon the structure of clay products. . 80 Investigation of building tile 81 Resisting power of earth 81 Strength of brick piers 81 Composition of window glass 81 Testing of clay products 81 Cooperation with technical societies 82

Sand lime brick 82 Strength of lime mortars 82

Properties of lime 82

Effect of temperature during the hydration of lime 83

Plasticity of lime 83 Use of lime in Portland cement mortar 83 Properties of gypsum 83

Lime testing 83 Information as to lime and its products 83

Textile investigations 84

Shrinkage of wools 84

Information as to textiles 85

Paper investigations 86

Paper conference 86 Paper testing 86 Information as to paper 87 Hack-saw blades 87 Properties of rubber 87 Tests of miscellaneous materials 88

8. Engineering research and testing 88

Applications of the dimensional method to physical problems. . 88

Windage resistance of steam turbines 88 Water-current meters 88

Anemometers 89

Gasoline engines 89

Vacuum traps 89 Hose couplings 89 Miscellaneous instruments and devices 90

Facilities needed for engineering research 90
CONTENTS. 7

Page.

III. Office, and engineering and construction 90

1. Office ." 90

Publications 90

Library 91

Correspondence 92

Storeroom 92

Personnel 92

Appropriations and accounts 92

Summary of tests and fees 94

2. Engineering and construction 94

Mechanical plant 94

Construction facilities 95

Care of buildings and grounds 95 IV. Recommendations 95

Buildings 95 Transverse testing machine 96

Radio laboratory 96

Additional ground 97 Additional scientific assistance of the minor grades 97

Clerical services 97

Skilled and unskilled labor 97 Increases of funds for special investigations 98

Standard materials 98

Investigation of textiles, paper, leather, and rubber 98

Investigation of clay products 98

Color standards and specifications 98

Covering for meter-testing tank : 99

Repairs and alterations 99
i
REPORT

OF THE

DIRECTOR, BUREAU OF STANDARDS

Department of Commerce,

Bureau of Standards,

Washington, July 1, 1914-

Sir: There is submitted herewith a report of the work of the

Bureau of Standards for the fiscal year ended June 30, 1914.

I. FUNCTIONS, ORGANIZATION, AND LOCATION.

Since the Bureau of Standards deals almost entirely with scientific

and technical problems, the following brief statement as to its functions and organization may be of assistance to those who are more or

less unfamiliar with its work.

The standards with which the Bureau is authorized to deal may

be conveniently classed as follows : First, standards of measurement

second, standard values of constants; third, standards of quality;

and, fourth, standards of mechanical performance.

1. STANDARDS OF MEASUREMENT.

A standard of length may be taken as an example of a standard

of measurement. It must be a length which is unchanging, reproducible, and capable of being compared with the working standards

used in the most precise scientific work or with those used in commerce and industry. The fundamental standard must be subdivided

and working standards prepared of these parts; for the measure- ment of greater lengths, standards must be prepared which are multiples of the fundamental standard. This process of subdividing and

multiplying the standard involves even more difficulties than those

met with in the preparation of the fundamental standard itself.

The construction of a set of standard weights from a single unit

is also an illustration, but a whole set of standard weights must be

prepared before the standard weight of the Government can become

available to the public. When the standard of length or weight has

been found with as many desirable qualities as possible, and before

the working standards of the subdivisions or multiples can be prepared, the question as to the method of comparison arises which

again involves the solution of difficult scientific problems in connection with the balance or the methods used. These balances range

from that capable of measuring the thousandth part of a milligram

to the large testing machine capable of measuring a load of thou-

- 9
10 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

sands of tons. The complete range must be covered, which involves

not only a large number of working standards, all of which must

agree with the fundamental standard, but apparatus suitable for

the comparison of these standards with all of the lengths or weights

found in practice.

These steps and equipment are absolutely essential in order to secure uniform measurements of length or weight throughout the

country, and they have their counterpart in every quantity that has

to be measured, whether it be length, weight, temperature, heat, light, or the various electrical measurements or other standards of measurement. These standards in one form or another are involved in

practically every scientific investigation, industrial process, or engineering structure.

2. PHYSICAL CONSTANTS.

There are many fixed relations between physical quantities, the

values of which it is extremely important to know. These values are usually termed " physical constants " and are used in every branch

of scientific work or industry. The amount of heat required to

change a pound of water into steam under normal conditions and the

relation between heat and mechanical energy are two important

physical constants; their values are used in practically every computation in connection with the designing of steam engines and boilers, the tests of their efficiencies or the measurement of their output.

The amount of heat required to turn liquid ammonia into vapor or the amount of heat required to melt a pound of ice are constants

equally important in the refrigerating industries. The value of the

relation between electrical and mechanical energy is involved in

many important commercial transactions concerned in electricity.

Accurate and authoritative values of these constants are just as

essential as in the case of standards of measurement. Many of these

now in use are old and obsolete and need redetermination by means

of the best modern facilities for physical measurement. Their determination involves the most difficult and precise work in all

branches of physics and chemistry—a fact not generally known by

others than those engaged in the scientific and technical work where

these constants are used.

3. STANDARDS OF QUALITY.

A standard of quality for a given material may sometimes take the

form of a sample of that material with which other materials of the

same kind can be compared, but this is generally a makeshift of the

poorest sort. It is only resorted to in the absence of definite and

reliable specifications in terms of measurable properties; that is to

say, a standard of quality of a material usually takes the form of a

specification or definition of its properties, involving, of course, the

measurement of those properties by means of the usual standards of

measurement. A certain kind of steel, a cement, a paint, an oil, or a paper or cloth, is found by use to be good or poor. The question then

arises, Why is it good or poor; what are the physical or chemical

properties or the particular combination of elements which make it of

good or poor quality ; how are its properties to be measured or its con-
REPORT OP DIRECTOR OP BUREAU OF STANDARDS. 11

stituents determined? These are questions for the laboratory to

answer and involve physical and chemical investigations of the most

difficult sort. A standard of quality for a given material necessarily takes into

account the purpose for which the material is to be used ; to set the

standard too low results in losses, poor efficiency, and even loss of

life; to make it too high may result precisely in the same thing;

that is to say, the material must be suitable for the purpose intended,

and the Bureau's investigations in connection with the properties of

materials are to enable the user of these materials, first, to select intelligently the material best suited for the purpose, second, to specify

it in terms which the producer can not mistake, and third, to make

the necessary tests to ascertain whether or not the material supplied

is in accordance with the specifications.

The actual testing of materials by the Bureau of Standards to

ascertain whether or not they comply with specifications is confined

almost exclusively to Government purchases, but in making these

tests (in which the Bureau has had the hearty cooperation of practically all the departments of the Government service) it is compelled to make many investigations concerning the properties of

materials, their specification and measurement. While this work

is of great value in placing Government purchases on a correct

business basis, the results of the investigations as to the properties

of materials and the information gained in testing Government supplies is even more important to the general public, and is distributed

in the form of suitable publications.

The Bureau does not compete with private testing laboratories

but endeavors to assist them by the development of standard specifications, methods of measurement, and other matters where uniformity is desirable, much of which information, as stated above, is

secured in connection with the testing of materials purchased by

the Government and a close observation of their use. The time is not far distant when it will be required that all materials bought or sold shall be as represented, but it should be kept

in mind that this is impossible except in the case of those materials

where proper standards of quality and methods of measurement

have been developed. It must not be assumed that the purchaser

or user is the party principally benefited in the development of

such standards; on the contrary, the manufacturer, first of all, is

interested in the quality and all things which affect the quality

of his product, and while the Bureau's efforts in this field are devoted principally to the pointing out and measurement of those

properties upon which the quality of the materials depend, it is to

be regretted that its force and equipment is insufficient to render

more assistance to manufactures with a view to a direct improvement of those parts of the process upon which the quality of the

output depends.

4. STANDARDS OF PERFORMANCE.

The value of an instrument, device, or machine almost always depends upon the efficiency of its performance. In such cases it is

necessary to state the performance desired or guaranteed in terms

which are correct and susceptible of measurement. As in the case of
12 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

standards of quality, the standard involved is more often in the form

of a specification, but specifications are useless unless based upon correct scientific and mechanical principles and supplemented with a statement of the method to be used in ascertaining whether or not

the specifications or guarantees have been complied with.

The performance of an engine or boiler, a pump, an electrical generator or motor, a weighing device, or a telescope, can usually be

measured, but the quantities to be measured and the method used

must be specified correctly and understood by all the parties con- cerned in the construction, purchase, or use of such apparatus. To

do this properly involves the use of standards of measurement, standard values of constants, and standards of quality. The Bureau of

Standards does not attempt to cover this field completely, but only

those cases where there is a lack of definite information upon which

to base specifications and only to the more important classes of apparatus. To secure this information involves investigations quite as

scientific in character and as difficult as in the case of other standards, as well as a knowledge of technical and manufacturing processes. The Bureau's activities in this field have only been developed to a

slight extent and almost entirely in connection with Government

purchases. It has had in this, as well as in the field of the properties

of materials, the most hearty cooperation of the various Government

experts, manufacturers, engineers, and technical societies.

Government purchases are not greatly different from those of the

public. Whenever the Bureau makes a scientific investigation or

secures information from other sources for the purpose of the improvement of specifications used in connection with Government purchases, whether for measuring instruments or for materials or equipment, such information or data is given to the public in the form of

suitable publications. The value of this information from the standpoint of the public is even greater than that in connection with

Government purchases, important as the latter is. In other words,

the needs of the public and the Government service are precisely the

same as far as standards or specifications are concerned, whether it

be standards of measurement, quality, or performance.

In the case of the public, the Bureau confines its work to those investigations, experimental or otherwise, which enable it to give

intelligent advice regarding the use, purchase, and testing of the more

important apparatus and materials, leaving the testing to commercial

laboratories; except, of course, in the case of standards of measurement, where it is absolutely essential that the standards of the public

be compared Avith those of the Government to secure uniformity of

measurement, and in unusual cases of testing where the public is

not yet provided with suitable means or equipment. In the case of

the Government, the Bureau goes further and serves as a testing

Bureau for the various departments when called upon, and^as such

is assisting to place Government purchases upon an economical and

businesslike basis. The example of the Government in such matters

has a far greater influence upon the public than most people suppose*.

The Government can do no greater service to the country than to

place its own purchases qn a basis which may be taken as a standard

by the public at large.
REPOBT OF DIRECTOR OF BUREAU OF STANDARDS. 13

5. RELATION OF THE BUREAU'S WORK TO THE PUBLIC.

It is perfectly obvious, even to one unfamiliar with the subject,

that the maintenance on the part of the Government of correct

standards of measurement or quality or performance calls for con- tinuous scientific and technical investigations of the highest grade,

involving the most competent expert services and the best scientific

equipment. When this is accomplished, there still remains the

serious problem of making the results available and useful to the

public.

The Bureau compares with its own standards of measurement the

standards or measuring instruments of States, cities, scientific laboratories, educational institutions, manufacturers, Government bureaus, or the public, for which a nominal fee is charged, except in

the case of the National and State Government institutions. It gives

advice concerning these standards or their use, whether it be in

connection with the enactment of laws, regulations, or ordinances

concerning the weights and measures of everyday trade or in con- nection with precision standards used in scientific work and the

industries. It gives advice upon request to State and city officials,

public-service commissions, public-utility corporations, regarding the

standards of measurement, of quality or performance, involved in

legislation or regulation pertaining to the public utilities. Many

questions of disagreement between the public and utility companies

as to these matters are referred to the Bureau for advice or adjustment, often avoiding unfair or inconsistent regulations, as well as long-drawn-out and expensive litigation. There is a great need on

the part of the public for unbiased and reliable information pertaining to the standards entering into the regulation and sale of the

services of public utilities. As far as possible such information is given in the form of publications upon definite subjects.

It must not be inferred from the above that the Bureau's activities are devoted principally to the interests of the user or consumer. The fundamental facts regarding standards of measurement, quality, or performance are the very things which most deeply concern manufacturers ; they are fundamentally concerned, either directly or indirectly, with the improvement of methods of production or the

quality of the output. It may be said that the Bureau occupies some- what the same position with respect to the manufacturing interests

of this country that the bureaus of the Agricultural Department do

to the agricultural interests. Many industries are just beginning to

realize the importance of precise methods of measurement and scientific investigation, which, in practically every case, involve some

kind of measurement.

It is upon quality as well as upon price that competition must

finally depend, whether in domestic or foreign commerce. The use

of exact methods and scientific results is the greatest factor in the

improvement of quality, efficiency, or the development of new industries. The educational value of the Bureau's work in this respect is

almost entirely unknown to the general public, and yet the Bureau

receives hundreds of letters, as well as many personal visits from

manufacturers, seeking information as to standards of measurement,

how to use them, how to measure the properties of materials, or as
14 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

to the fundamental physical and chemical principles involved; also,

what is of even greater importance, how to initiate and carry out

scientific investigations and tests on their own account in their particular fields of work.

The importance of maintaining scientific institutions having to

do with standardization and the application of precise measure- ments to the industries has been recognized by all the leading countries of the world. Great Britain maintains the Standards Department of the Board of Trade, which is in charge of the standards

and inspection service of the trade weights and measures; also the

National Physical Laboratory, whose functions include matters pertaining to scientific and technical standards, physical constants, and

to some extent the properties of materials. The Laboratoire d'Essais,

of France, while not as extensive as the English institution, is

charged with similar duties. Germany maintains three such institutions—the Normal-Eichungs Kommission, equipped with the buildings, personnel, and apparatus necessary in standardizing and controlling the weights and measures of trade; the Physikalisch-Technische Reichsanstalt, covering testing and investigations in connection with scientific and technical standards other than weights and

measures; and the Prussian Government maintains the Materialpriifungsamt, a large institution devoted to the investigating and

testing of structural, engineering, and other materials.

It is generally recognized that these institutions have been exceedingly important factors in the industrial progress of these countries.

6. ORGANIZATION.

The organization of the Bureau's scientific and technical staff is based upon the nature of the expert service involved rather than

upon the classes of standards. For example, the division of weights

and measures has to do with all matters pertaining to> standards of

length, mass (weight, as it is commonly termed), time, density, and

similar questions, whether they arise in connection with the precision

standards used in scientific investigation, the master standards of

manufacturers, or the ordinary weights and measures of trade. A

standard of quality or performance where any of the above measure- ments form the fundamental and most important factor would be

referred to this division.

The division of heat and thermometry has to do with heat standards, the testing of heat-measuring apparatus, the determination of

heat constants, of which there are many, and all investigations pertaining to quality or performance where heat measurement is the

essential and predominating factor.

Similarly, the electrical division is concerned with all the electrical

problems that may be taken up at the Bureau, whether in connection

with the various electrical standards of measurement, electrical constants, the electrical properties of materials, or the performance of

electrical equipment.

Questions in optics enter into standards of all kinds to a greater

extent than has been supposed ; hence, there is an optical division

provided, with experts in spectroscopy, polarimetry (used in sugar

analysis), color measurement, the principles of optical instruments,

and the measurement of the optical properties of materials.
REPORT OF DIRECTOR OP BUREAU OF STANDARDS. 15

Practically all investigations concerning the various classes of

standards involve chemistry in one form or another. There are also

many chemical standards and questions which arise in connection

"with chemical work generally, especially in the industries; hence,

there is a chemical division, cooperating with every other division

of the Bureau, as well as taking care of the questions of a purely

chemical nature that come to the Bureau and which fall within its

functions.

In the case of the more important technical fields, divisions have

been formed dealing more specifically with large and important

classes of materials, but many of the purely scientific questions involved would be handled by one of the above scientific divisions or

jointly with it. The work of the technical divisions is just as scientific in character, but deals more specifically with manufactured

products.

The work of the structural engineering and miscellaneous materials division includes the investigation, testing, and preparation

of specifications for the above materials, such as the metals and their

alloys, stone, cement," concrete, lime, the clay products, paints, oils,

paper, textiles, rubber, and other miscellaneous materials.

The division of engineering research makes investigations and

tests regarding the performance and efficiency of such instruments,

devices, or machinery, as the Bureau may take up that do not fall

directly under one of the scientific divisions. The division is a small

one and its work is devoted almost exclusively to assistance given

other departments of the Government and the General Supply Committee in designing, specifying, or testing equipment. It should in

time form one of the most important branches of the Bureau's work.

The questions pertaining to the manufacture, specifications, test- ing, and use of the metals and their alloys have become so important

that a division known as the metallurgical division has been formed

of the experts engaged in these problems.

The employees engaged in clerical work, purchasing, files, rec- ords, accounting, and library, are known as the office division', while

those employed in the operation of the mechanical plant, the various

shops, and the care of the buildings and grounds, form the engineering and construction division.

7. LOCATION.

The laboratories of the Bureau of Standards are located in the

northwest section of Washington, on Pierce Mill Road, near Connecticut Avenue, and are reached by the Chevy Chase car line. It

was located outside of the business center of Washington in order to

insure freedom from mechanical, electrical, and other disturbances

common to the business and more thickly populated sections of the

city. Furthermore, the area of ground necessary precluded a site

near the city. It has been found by experience that the efficiency

of the employees, especially those engaged in testing and scientific

investigation, has been greatly increased by the location of the

laboratories in a section free from the ordinary disturbances of city

life.
16 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

n. SCIENTIFIC AND TECHNICAL DIVISIONS.

1. WEIGHTS AND MEASURES.

Weights.

During the year 16 States have had standard weights tested. In

some cases the weights submitted for test were new and of modern

manufacture and design, and in others they were very old and were

either tested for temporary use or discarded. The number of States

submitting standards for test and the character of the standards indicate the increased interest that is being taken by the public in

weights and measures work. The Bureau has tested for the Post

Office Department 80 sejts of test weights, which are to be shipped

from place to place by that department for use in verifying scales

in use in its dealings with the public. The necessity and the desirability of the Government maintaining accurate scales of highest

standard in its transactions with the public has been pointed out on

various occasions by this Bureau.

Cast-iron weights, under investigation for several years, have

shown conclusively that such weights must be checked at least once

a year to insure their accuracy, even when not in use. Improvement in the design of what are commonly called test weights has received a great deal of attention by this Bureau, and

manufacturers, following the suggestions of the Bureau, are now

producing reliable weights of this kind. Further efforts are being

directed toward reducing the cost of these weights, since large numbers of them are used by local sealers of weights and measures. Improved facilities for work of the highest precision were secured

at the close of the year by the construction of a double walled constant temperature room, which is divided into separate compartments

for the balances and the operator. The work of fitting up this room

will be carried on as rapidly as the routine work will permit.

Capacity Measures.

The number of capacity measures tested during the past year

amounts to 295, as compared with 66 the previous year, there being

a large increase in the number submitted by the United States Government and State institutions, as well as by private parties. There

has also been a large increase in the number of cubic-foot bottles or fractional cubic-foot bottles submitted for test for use as standards in the testing of gas meters.

With the enlargement of the division's quarters, made possible by

the removal of the electrical division to the new east laboratory,

more space has been allotted to the work of testing capacity measures, resulting in the work being handled much more satisfactorily.

There was a considerable decrease in the number of length measures submitted for test, due to a great extent to a less number being

presented by the Government. A 100-foot bench standard, located

in the City Hall, Chicago, was graduated and standardized for the

Western Society of Engineers.

The Bureau has cooperated with the manufacturers' standardization committee with a view to securing greater uniformity in the use of the American Briggs pipe thread standards, and it is expected
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 17

that a set of standards on this system will be deposited with the

Bureau.

Inspection of Scales.

One man has been detailed at Chicago during the entire year to inspect scales being manufactured for the Post Office Department. Two

thousand one hundred and thirty-two scales have also been tested

for the Post Office Department at a factory in Vermont. The advisability of having scales purchased by the Government thoroughly

inspected and tested before being accepted, and of having this work

done at the factory, as recommended by the Bureau on previous occasions, has been fully demonstrated by the scale inspections at the

factory.

In addition, the Bureau has received many requests from the Navy

Department and other departments to test scales, but all of these

requests could not be complied with on account of lack of sufficient

force and equipment. The same was true in several instances where

tests were desired by corporations or individuals in States where such

work has not yet been taken up by State or local authorities. In

some of these latter instances it was clear from the correspondence

that the results obtained from the use of the scales in question were of

vital importance to the communities or individuals concerned.

Cement Sieve Testing.

The methods of testing the sieves used in the testing of cement has

been well systematized so that this is now quite a routine matter. As

a result there has been a great improvement in the quality of the

sieves submitted for test and the percentage of rejections has been

greatly reduced.

Time.

Early in the year a room for the testing of watches was prepared,

and was equipped with heating and cooling apparatus, fans for the

circulation of the air, thermostat and automatic switch for controlling the .temperature. Proposed regulations for the testing of

watches were drawn up and submitted to the various jeweler's journals and to manufacturers of watches, together with a statement of

the preliminary tests that had been made at the Bureau, and its plans

for the future testing of watches for criticism. A conference of

watch manufacturers was held at this Bureau in February, at which

these regulations were discussed. Practically no change in the regulations was made by this conference, and the regulations were put

into effect by the Bureau. The first watch test was made in April,

and the Bureau is now prepared to hold these tests regularly four

times a year. It is confined to the higher grades of watches only,

for which a fee is charged.

Gas-Meter Testing.

The investigation of various methods and devices for measuring

gas during the past year has been developed with considerable sat- isfaction. The use of oil instead of water in cubic-foot bottles has

been under trial for several months and promises to be an improvement over the usual method. A method of testing laboratory gas

65301°—14 2
18 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

meters has been devised which has a number of advantages over that

now in use. An investigation of the factors affecting the accuracy

of laboratory wet-gas meters is in progress. An improvement in

meter provers to minimize errors in testing dry-gas meters, and other

apparatus, is being developed. An extensive investigation of the

closeness with which the discharge of acetylene burners of various

manufacture occur was made and some valuable and interesting

results were obtained. During the year a few laboratory gas meters

for laboratories outside of the Bureau were tested, and also a number

of meters of the same type for various kinds of Bureau work involving the measurement of gas.

Volumetric Glassware.

The routine testing of volumetric apparatus to be used as standards

and for precision work in chemical laboratories and by the Government included flasks, cylindrical graduates, burettes, and pipettes.

During the year this testing comprised 3,344 pieces of apparatus

;

and 1,213 hydrometers, principally for the Internal-Revenue Service

in connection with the collection of revenue on distilled spirits, were

examined. In addition to these tests 109 density determinations

have been made. Aside from the routine work just mentioned, a large amount of research has been carried on by the volumetric

section with a view to the improvement of the design, testing, and

use of volumetric standards.

An investigation of the density and thermal expansion of milk and

cream has been made for the dairy division of the Department of

Agriculture, and a similar investigation of linseed oil and turpentine

was completed for the American Society for Testing Materials.

This last work was a continuation of and supplementary to the work

done for the society three years ago. During the year work on the

expansion of petroleum oils has been continued and a very considerable amount of data is now available. It is expected that during the

coming year the work will be completed and tables prepared for the

use of oil inspectors and others who may have occasion to use information on the rate of change of density and volume of oil with

change of temperature.

Expansion of Materials.

An investigation of the expansion of a bronze bar diie to changes

in temperature has been carried on for some months. This property

of the bronze bar in question was first investigated in an oil bath

in temperatures ranging from 20 to 150° C. ; subsequently an electrical furnace was employed between the temperatures of 17 and 630°

C. ; and later a third series of observations between 14 and 300° C.

were made with a new dilatometer and oil bath. The results of these

investigations showed, first, the precision of the method with three

different pieces of apparatus; second, the regularity with which the

bronze assumed a definite length at a definite temperature ; third, indications of structural rearrangements too small to be detected by the

ordinary cooling-curve method of thermal analysis; and fourth, the

possibility of maintaining the material while being heated (under

certain conditions) in an unstable state and in which it expands much

less than ordinarily.
BEPOBT OF DIRECTOR OF BUREAU OF STANDARDS. 19

The thermal expansion of samples of glass, porcelain, and brass

have also been investigated.

An investigation has been commenced to determine whether any

relation exists between the thermal expansions of a metal and the

simultaneous changes in its electrical resistance. This was undertaken partly for the purpose of determining, if possible, a method of

checking one class of measurements by means of the other, and

partly to accumulate data that might have other practical as well as

theoretical application. The results already obtained show that, in

at least some cases, readjustments of internal structures that are accompanied by minute increments of length are also accompanied by

corresponding increments of electrical resistance.

Barometry.

Investigations of mercurial and aneroid barometers have been

carried on during the year and problems of practical application

have been studied and experimented upon. A standard method has

been adopted for the testing and certification of high-grade aneroids.

This test emphasizes the discrepancies between the results obtained

with pressure changing rapidly, as compared with slow changes; also

that the instrument should be free from various mechanical errors frequently met, and that it should include a simple temperature test. Besides the standard method, a short method of testing has been

adopted for low-grade aneroids and a definite method is about to be

adopted for testing short-range aneroids used in navigation and in

the household.

During the year two representative aneroids taken abroad in the

summer of 1913 were tested at the national standardizing laboratories of Germany, England, and France. The reports have been

analyzed and the data are most interesting and leave no doubt as to

the superiority of our own method.

In the past year an improved method of setting a mercury surface

to a required height has been devised, by means of which the accu- racy of certain types of barometers and other pressure gauges involving the use of mercury, may be increased.

Track Scale Testing Equipment.

The railroad track scale testing equipment of the Bureau, secured

under an appropriation of $25,000, available July 1, 1913, was completed and ready for service in September. During the- year tests

were made on 38 railroad scales in Connecticut, Vermont, New York,

and New Jersey. The tests made in the two latter States were for

the Customs Service in the vicinity of the Port of New York.

Aside from the value of these tests as indicating the accuracy of

the scales examined, they yielded much data which will be of value

in determining the best methods of testing such scales and improving

the design, with a view to obtaining greater accuracy and reliability.

Allowing a tolerance of 0.2 of 1 per cent, which, in the opinion

of the Bureau, is a fair tolerance for such scales, 80 per cent of the

16 scales tested in Vermont would have been rejected ; on a tolerance

of 0.4 of 1 per cent 60 per cent would have been rejected ; and on a tolerance of 1 per cent 40 per cent would have been rejected. The

magnitude of some of the errors was as follows: 1,349 pounds with a
20 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

load of 35,000; and 1,149, 1,129, and 2,459 pounds on three scales

with loads of 70,000 pounds. Of the 16 scales tested at the Port of

New York, 75 per cent would have been rejected on a tolerance of 0.2

of 1 per cent, 56 per cent on a tolerance of 0.4 of 1 per cent, and

25 per cent on a tolerance of 1 per cent. The above results clearly show the necessity for periodic inspection

of such scales and indicate to some extent the great losses which may

be sustained by the use of uninspected track scales. As previously

pointed out, the inspection of railroad track and elevator scales

should be taken up by or under the supervision of the Federal Government, rather than by the States, for the reason that practically

all shipments weighed upon them are interstate.

Eequests for services of the car have been received from State and

city officials and others in a number of States, among which may be

mentioned Ohio, Indiana, Illinois, Missouri, Iowa, Minnesota, Wisconsin, and Tennessee, and, no doubt, many other requests will be

filed from time to time. It is obvious that one, or even two, cars could not comply with all these requests within a reasonable time, to

say nothing of many other scales in every State in the Union which

should be inspected. While another car will be procured under the

appropriation of $40,000, available July 1, 1914, it is evident that

additional cars will be required in the future for this work.

It is respectfully recommended that Congress be urgently asked

to increase the sum available for the investigation and testing of

railroad track scales, elevator scales, and scales purchased by or belonging to the Federal Government, and also to provide facilities

for cooperating with States in their endeavor to bring about uniformity in weights and measures. With the $40,000 made available July 1, 1914, an additional test car of 75 tons capacity will be provided and also a master scale on

which the 10,000-pound weights used in this work may be compared. These two items with the additional help needed in this

work and the expense of keeping two cars in the field will consume

the amount provided. The numerous demands for the car now

available clearly demonstrate that if the Bureau is in any way to

adequately occupy this field it should have additional cars with the

necessary equipment and crews to operate them.

Assistance to Porto Rico.

At the request of the Bureau of Insular Affairs this Bureau detailed one of its experts, to organize an inspection department of

weights and measures for the island of Porto Eico, under an act of

August 18, 1913, requiring the inspection of all commercial weights

and measures in use under the supervision of the Secretary of Porto

Pico.

It devolved upon the Bureau's representative to devise a system

of keeping records suitable for the service, to advise what kind and

quality of apparatus should be obtained for primary standards and

for the use of the inspectors. Keeping in view the amount of the

appropriation available, the needs of the service, and the climatic

conditions; to make rules and regulations for the enforcement and

clearer understanding of the law, as provided by section 10 of the

act; to write explicit instructions and devise tolerances and specifica-
REPORT OP DIRECTOR OF BUREAU OP STANDARDS. 21

tions for the guidance of the inspectors; and, finally, to instruct

them in the duties of their office. Thus, there was established at the beginning a complete record

system, and an organized force of inspectors, equipped with suitable

apparatus and provided with specifications and tolerances for the

inspection or rejection of apparatus, the entire organization and its

management being based on years of experience, and having at the

outset a degree of perfection such as has not been obtained by States

of the Union after years of experience.

Too much emphasis can not be laid upon the importance of properly establishing an inspection department at the outset and avoiding methods of inspection and administration which are at once inimical to the best interests of the consumer and detrimental to the merchants. By properly establishing a weights and measures department at the beginning, results favorable to the consumer, as well as

to the honest merchant, immediately accrue, and all prejudice against

weights and measures inspection is thus forestalled.

In this connection attention is called to the fact that opportunities

for rendering similar services to States in the Union are continually

arising, and it is to be regretted that the funds, as well as the force,

available for such work, are entirely inadequate to meet the needs.

Weights and Measures Conference.

The Ninth Annual Conference on Weights and Measures was held

at the Bureau of Standards in May of this year, and was more largely

attended than any previous meeting, there being representatives from

26 States and the District of Columbia and 67 cities and counties ; in

all, 116 officials. There was also present a large number of manufacturers and other persons interested in the subject of weights and

measures. In addition to an excellent program, an interesting and

instructive feature of the meeting was the exhibit by manufacturers

of various types of weighing and measuring apparatus.

The wisdom of these conferences being fostered by the Bureau is

demonstrated each year by the fact that increased interest is taken

in them because of their association with a Federal bureau; by the

cooperative work accomplished tending toward uniformity in the

weights and measures legislation passed by the various States; and

in the tolerances and specifications for commercial apparatus adopted

by a number of the States. These conferences not only bring the

State and city officials in contact with the Bureau, but are of great

assistance to officials from States and communities newly organizing

weights, and measures service.

Legislation.

An act of Congress, important in the field of weights and measures and one which has received a great deal of attention by this

division, was approved March 3, 1913, making amendment to the

food and drugs act of June 30, 1906, which requires that the net

weight, measure, or numerical count shall be plainly and conspicuously marked on the outside of all packages containing food. Legislation of this character has been long sought by friends of honest

weights and measures, and success has finally been attained largely

through fear on the part of the opposition that the action of a few
22 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

States in passing legislation of this kind would be followed by many

other States, and thus manufacturers of products for interstate shipment would be obliged to comply with many laws having different

requirements and conflicting provisions.

In connection with this amendment the chief of the weights and

measures division of the Bureau represented the Secretary of Commerce on a committee of three, representing the Secretaries of Commerce, the Treasury, and Agriculture, appointed to draft rules and

regulations for the enforcement of this amendment.

Two weights and measures bills of importance are now pending

before Congress—one " to fix a standard barrel for fruit, vegetables,

and other dry commodities," and the other " to regulate and control

the manufacture, sale, and use of weights and measures." This latter

bill provides that the Bureau of Standards shall have the authority

to approve and shall approve the A

T arious types of weighing and

measuring devices which may lawfully be used in trade and commerce throughout the United States. The principles involved in each

of these bills have the hearty indorsement of the Bureau, and it is

hoped that the pending legislation will soon be enacted.

The division has also been keeping informed as to weights and

measures legislation passed by the States, obtaining carefully verified

copies, so that the Bureau's publication of State and national laws

" Concerning the Weights and Measures of the United States " may

be revised promptly when deemed advisable, and in order that cor- respondence may be more expeditiously and satisfactorily answered

than would be possible without having such legislation at hand.

Publications.

During the year there have been issued " The report of the eighth

annual conference on weights and measures " ; Circular No. 43, " The

metric carat " ; Circular No. 46, " The testing of barometers "

;

Scientific Paper No. 214, " Note on the setting of a mercury surface

to a required height," and Scientific Paper No. 219, " Production of

temperature uniformity in an electric furnace." The following proposed publications have been partially prepared : A circular on " The

testing of screws and screw threads " ; Circular No. 47, " Units of

weight and measure; definitions and tables of equivalents," (in

press) ; " Report of the ninth annual conference on weights and

measures"; " Measurement of time and testing of time pieces "; " Instructions for the guidance of weights and measures officials " ; " Tol- erances and specifications for commercial apparatus"; revision of

Circular No. 3, "Verification of standards of mass"; and a circular on " Wagon scales."

2. THERMOMETRY, PYROMETRY, AND HEAT MEASUREMENTS.

Calorimetric Resistance Thermometers.

Details of construction and the method of use of special resistance

thermometers have been developed by the Bureau for calorimetric

measurements requiring the highest attainable accuracy. (See Scientific Paper No. 200.) The construction of these thermometers for

the public has been undertaken by a well-known American instrument manufacturer and they have already found extensive applica-
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 23

tion in technical and university laboratories. The accuracy attainable with these thermometers is about ten times that previously

attainable with the best mercurial thermometers.

Melting Points of the Refractory Elements.

A joint investigation was undertaken with the metallurgical division, for the purpose of determining the melting points of elements

of the iron group—nickel, cobalt, iron, manganese, chromium—and

of vanadium and titanium by means of the micropyrometer, an

instrument developed in the laboratories of the Bureau for determining melting points of minute samples of materials. The melting

points observed and the degree of purity of the elements used are

stated in full in Scientific Paper No. 205 and lead to the conclusion

that the probable melting point of the pure elements are as follows

Ni 1452° C. ± 3 Cr 1520° C. toFe?

Co 1478° ± 5 Va 1720° ±30

Fe 1530° ± 5 Ti 1795° ± 15

Mn 1260° ±20

The paper supplies important chemical and metallurgical data on

some of which the existing data was quite conflicting.

Melting Points of Some Refractory Oxides.

A previous publication of the Bureau gave the results of determinations of the melting points of 62 samples of fire brick and of

materials of importance in the manufacture of fire brick. Further

determinations of the melting points of some highly refractory

oxides have been carried out in an electric furnace which could be

evacuated or supplied with a current of inert gas. The temperature measurements were made with an optical pyrometer. The

melting points found were

Cr2 3 1990° C, I CaO 2572° C. ALO-s 2050° I MgO 2800°

The data are of importance to the ceramic industries and in many

high temperature problems, such as the design of furnaces, etc.,

besides having a general physical-chemical interest. (See Scientific Paper No. 212.)

The Monochromatic and Total Emissivity of Nickel Oxide (NiO)

in the Range 600° to 1,300° C.

An investigation has been under way for some time to determine

the radiating properties of metals and oxides at high temperatures.

In many industrial operations the only available method of measuring the temperatures is by means of optical pyrometers which

measure the intensity of the light, or by radiation pyrometers which

measure the intensity of the heat (and light) radiations emitted by

the hot body, the temperature of which is to be measured. As the

radiating properties are different for every material, it becomes

necessary to determine these properties to enable the technical man

to correct his observed pyrometer readings to the true temperature

of the material under observation. These corrections are in some

cases very considerable, amounting to several hundred degrees centigrade or more for some of the metals in their molten condition.
24 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

In a previous paper (Scientific Paper No. 121), the Bureau published data for correcting the observed readings of optical and ra- diation pyrometers when used to measure the temperature of redhot copper, in the solid and in the molten state, when the surfaces

were clean and when oxidized. In the present paper similar data

are given for nickel oxide surfaces in the range 600° to 1,300° C.

The Specific Heat of Copper.

Copper enters into the construction of calorimeters and its specific

heat and the variation of its specific heat with temperature must be

known with an accuracy higher than could be obtained from existing data. It was therefore necessary for the Bureau to undertake

its redetermination in the ordinary range of temperature of calorimetric work to an order of accuracy demanded by several important

calorimetic investigations now. well under way in the laboratories of

the Bureau.

The copper was annealed wire, 99.87 per cent pure, according to

chemical analyses. The results of 27 determinations at temperatures

between 15° and 50° C. show an average deviation of 1 part in

1,000 from 0.3834+0.00020 (t°—25°) international joules per gram

degree or 0.0917+0.000048 (t°—25°) calories (20°) per gram degree

'if 4,182 joules be taken as equal to 1 (20°) calorie.

Latent Heat of Fusion of Ice.

The latent heat of ice, or conversely the amount of heat that must

be removed from unit mass of water at 32° F. to freeze it to ice at

that temperature, is one of the fundamental constants of refrigeration engineering. Previous determinations of this constant are not

in good agreement. Engineers in their computations use values

ranging from 142 to 144 British thermal units per pound. The

Bureau having been asked by refrigeration engineers, through their

technical societies, to standardize practice, a new and careful determination of this constant was undertaken by the Bureau. Two independent methods of experimentation were used, which gave re- sults in agreement to about 1 part in 2,000. The result found for the

latent heat of ice was, 79.63 calorites (15° C.) per gram mass$ 143.33

B. t. u. per pound mass, or 143.5 B. t. u. per pound weighed in air

against brass or iron weights.

The results of this investigation were communicated to the Third

International Congress on Befrigeration, held at Chicago in September, 1913. (See Scientific Paper No. 209.)

Industrial Gas Calorimetry.

Legal requirements are tending toward the specification of the

heating value for gas. An investigation was accordingly undertaken at the request of American gas engineers to furnish information to engineers, inspectors, and public-service commissions as to

the sources of error, important precautions in the use of, and ac- curacy attainable with the various calorimeters widely used in the

gas industries.

An exhaustive investigation was made of nine different makes of

calorimeter that have found extensive use in the gas industries for

the measurement of the heating value of gas. An analytical investigation was made of the various heat losses from the calorimeters;
BEPOET OF DIRECTOR OF BUREAU OF STANDARDS. 25

of modifications in the method of operation to reduce these heat

losses; and of the effect of operating the calorimeters at different

rates of gas consumption, air supply, etc., and under different conditions of atmospheric humidity; and sources of error in metering

the gas. The several gas calorimeters were intercompared and one

of them was compared with two calorimeters of the bomb type, using

different gases (hydrogen, illuminating gas, and natural gas). (See

Technologic Paper No. 36.)

Standard Methods of Gas Testing.

In order to make available to gas engineers and inspectors the re- sults of the exhaustive investigation of gas calorimetry, briefly outlined above, the Bureau has published (see Circular No. 48) specific

directions for operating gas calorimeters that will enable the user

to obtain accurate and reliable results. It is hoped that this publication will place before American gas engineers detailed directions for

an approved and authoritative method of gas testing, thus filling

the place in American gas-testing practice that has been filled in

English practice by the Notifications of the Gas Referees.

Combustion Calorimetry and the Heats of Combustion of Cane

Sugar, Benzoic Acid, and Naphthalene.

The Bureau has designed a special calorimeter for the determinations of the heats of combustion with the highest attainable accuracy,

and has measured the heats of combustion of cane sugar, benzoic

acid, and naphthalene, the three substances that are now regularly

sent out by the Bureau as standard combustion samples and widely

used by chemists and engineers for the standardization of the calorimeters used for testing the heating values of fuels, foods, etc. The

widespread and growing demand for these standard samples emphasizes the importance of this investigation.

The use of these samples enables the user of a calorimeter to

quickly check the accuracy of his work, and has practically reduced

the work of all calorimetric laboratories to a uniform and comparable

basis. Before such checks on the accuracy of the work were possible, cases had been called to the attention of the Bureau where tests on

the same samples of fuels in the laboratories of the purchaser and

the seller differed by amounts sufficient to affect the basis of settlement by thousands of dollars annually, as the fuels were purchased

on the basis of their heating value. The heating values found were

as follows

Cane sugar=3,949±:2 calories (20°) per gram

Benzoic acid=6,329±l calorie (20°) per gram

Naphthalene=9,622 ±1 calorie (20°) per gram

where the substances are weighed in air against brass weights.

Cold-Junction Correction for Thermocouples.

Cases have come to the attention of the Bureau where errors in

these temperature-measuring instruments as great as 50° C. were possible, owing to erroneous application of the correction for the coldjunction temperature. Scientific Paper No. 202 was written with the

aim of impressing upon the technical man the necessity of using some

caution in the matter of the cold-junction temperature of thermocouples. This paper gives the details of the methods of applying the
26 REPORT OP DIRECTOR OP BUREAU OF STANDARDS.

proper corrections and discusses briefly devices for the elimination

of the cold-junction corrections.

Ocean Temperatures in the Vicinity of Icebergs and in Other Parts

of the Ocean.

The unfortunate accident to the Titanic centered attention on possible methods of detecting the proximity of icebergs. Great differ- ences of opinion seemed to exist as to the value of sea-water temperatures for this purpose. The usual method of roughly taking the

temperature of a pail of sea water at widely separated intervals of

time could give no useful information so far as detecting the proximity of icebergs is concerned. If any definite variations in the sea- water temperature are caused by the proximity of icebergs, then

continuous records of the temperature should be taken.

The Bureau having in use in its laboratories instruments for

obtaining continuous temperature records, it was deemed of suffi- cient importance to test the value of such records for the purposes

of detecting the near approach to icebergs. The necessary equipment

was hurriedly constructed and assembled and, through the courtesy

of the Navy Department, installed and operated by representatives

of the Bureau on the U. S. S. Chester and the U. S. S. Birmingham,

in the summer of 1912. A specially constructed electric resistance

thermometer, together with a Leeds and Northrup recorder, was used

to obtain continuous records of the sea-water temperature. This

equipment was sensitive to a few hundredths of a degree. Numerous

records of sea-water temperatures were taken while approaching and

cruising around icebergs and in other parts of the ocean. (See

Scientific Paper No. 210.)

The general conclusions reached were that the temperature variations in parts of the ocean far removed from ice are often as great

and as sudden as in the immediate neighborhood of icebergs, and

that it is not possible to draw positive conclusions as to the absence or proximity of ice from the temperature records of sea water.

The temperature records may, however, give valuable information

and warning of approach to shore and shallow water, on the location and identification of characteristic ocean currents, and even of

the proximity of ice in some parts of the ocean, distant from commingling ocean currents, where the temperature variations are less

sudden and erratic than in the regions where the above observations

were made.

An attempt was also made to detect, by means of the ships submarine telephones, the submarine echoes, from the submerged portion

of a large iceberg, of the sound waves sent out by striking the ship's

bell lowered under water. For lack of time and facilities these ex- periments could not be followed out, but as far as they went seemed

sufficiently promising to merit further trial.

The Bureau has had a scientific observer aboard the U. S. reve- nue cutter Seneca in its patrol of the North Atlantic Ocean with

a complete equipment for obtaining the necessary physical and

meteorological data. This work has been planned by, and is being

carried out in cooperation with the Revenue-Cutter Service, the

United States Weather Bureau, the Hydrographic Office, and this

Bureau. The biological work is being carried out by the Bureau

of Fisheries.
REPORT OF DIRECTOR OP BUREAU OF STANDARDS. 27

Refrigeration Constants.

, This very extensive investigation, undertaken at the request of

American refrigeration engineers expressed through their national

associations, includes the determination of the fundamental constants of refrigeration engineering. The results of the determinations of the first of these constants, viz, the latent heat of ice, have

already been briefly reviewed above. Other fundamental constants on which work is now progressing are

(a) The specific heat of ice. (6) The coefficient of thermal expansion of ice. (c) The specific and the latent heats of the liquids used in refrigeration,

such as ammonia, aqueous ammonia solutions, carbon dioxide, methyl chloride,

etc.(d) The specific heats of the vapors of the liquids used in refrigeration.

(e) The specific heats of brines.

(/) The specific volumes of saturated vapors of the liquids used in refrigeration.(g) The densities of aqueous ammonia solutions.

(h) The pressure-temperature relations of the liquids used in refrigeration.

(i) The thermal conductivities .of insulating materials used in cold storage

construction, in steel passenger and mail cars, in furnace construction, etc. Nearly all of the apparatus required for these investigations has

been designed and most of it has been constructed in the instrument

shops of the Bureau, and the more important pieces of apparatus

have been tried out in the laboratory with most satisfactory results.

This investigation has involved first of all the original design and

construction of a vast amount of accurate and complicated apparatus and the overcoming of what at times seemed most discouraging

experimental difficulties. Now that much of this work has been

accomplished, it is believed that experimental results will follow as quickly as can reasonably be expected.

The descriptions of the numerous pieces of apparatus, such as low

temperature thermostats, calorimeters, mercury manometers, piston

pressure gauges, etc., and of the experimental methods that have

been adopted can hardly be comprised within the space of a report

of this kind. It is believed that most of this schedule can be completed in the course of the next two years, with the completion of

which, it is confidently believed, the fundamental constants of re- frigeration will rest on a most satisfactory basis for many years to come. This work is being carried out with the cooperation of committees

of the American Association of Refrigeration, and the American

Society of Refrigerating Engineers, the members of which visit the

Bureau annually and keep in close touch with the work, and have

rendered valuable assistance by practical suggestions.

Heats of Combustion Gases.

American gas engineers have requested the Bureau to issue an

authoritative table of the heats of combustion of the more important

gases entering into the composition of manufactured gas. In view

of the fact that existing data are discordant and are based on methods

that are much inferior to those now available, further work is neces- sary before such a table can be issued with that degree of confidence

which would assure its universal adoption. Most of the necessary

apparatus required for this work has been developed and is now at

hand and some of the experimental methods to be used have been
28 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

tried out in the laboratory. This investigation requires a great

amount of chemical work in the production of the various gases in

the highest state of purity, and the determination of their heats of

combustion in calorimeters of special design capable of yielding

results of the highest attainable accuracy.

Resistance Thermometry.

In connection with the calorimetric platinum resistance thermometers that have been developed by the Bureau for measuring

small temperature changes of a few degrees with an accuracy of a few ten-thousandths of a degree, it has been necessary to design and

construct several special resistance bridges, the details of construction of which will be described in a forthcoming paper.

Heat Capacity of Water and the Mechanical Equivalent of Heat.

This investigation is of fundamental importance in fixing the primary unit of heat. In the half dozen or more extended pieces of

work that have been published on this subject, which may be said to

be more or less generally accepted, there appear startling discrepancies, and it is evident that this fundamental measurement has not

been made with anything like the degree of accuracy which modern

calorimetric practice demands. In the course of the calorimetric

researches that have been under way in the laboratories of the Bureau during the past several years, a great deal of valuable data have

been obtained on the capacity for heat of water. The work has

suggested improvements in apparatus and in methods of experimentation which will be tried out as soon as opportunity permits.

In view of the importance of the work and of the discrepancies in

existing data, it is deemed best to withhold publication until the work

has been carried out with the highest accuracy that can be obtained

by the best modern methods.

Radiation Pyrometers.

One method of measuring the temperature of heated objects, which

is particularly applicable to certain technical operations, and which

is coming into extended use, consists in the use of a radiation pyrometer, which measures the intensity of the total radiation (i. e., both the light and the longer heat waves) emitted by the heated

body. In the work of testing these instruments the fact developed

that their indications varied with the size of and with the distance

from the heated body, with the time of exposure, with the focusing,

etc. Accordingly, an investigation was undertaken of a number of

such instruments which had been submitted to the Bureau for test. This work, which is nearly completed, will treat in necessary detail

the various forms of radiation pyrometer, their calibration, sources of error, and applications in technical industries. It is hoped that

the data which will be submitted will result in a marked improvement in construction, and greater satisfaction in the use of this important type of temperature measuring apparatus.

Radiating Properties of Metals and Oxides.

This data is required to enable technical men to correct the observed

indications of optical pyrometers. As stated in a previous section

of this report, two investigations along these lines, on copper and
EEPOET OF DIRECTOR OF BUREAU OF STANDARDS. 29

on nickel oxide, have been completed. The radiation from other substances of industrial importance will be examined from time to time

as opportunity permits.

Behavior of Base-Metal Thermocouples at High Temperatures.

In view of the extensive use of these couples in the measurement of

temperature, it is of importance to determine the changes in their

readings due to long-continued exposure to high temperatures. A

number of such couples are now under test to obtain such data.

The Thermal Conductivity of Refractories at High Temperatures.

Little reliable data are available on the heat conductivity of building materials. Their conductivity has an important bearing in the

use of such materials, upon their behavior under fire conditions, their use in conserving heat, in furnace construction, etc. The first materials selected were graphite and amorphous carbon,

not alone on account of their importance in modern electric furnace

construction, but also to test out several new methods of determining

thermal conductivities at high temperatures, a constant extremely

difficult of determination. The preliminary experiments made thus

far promise success.

Industrial Viscosimetry.

The Bureau is constantly receiving requests from technical men for

information on the measurement of the viscosity of lubricating oils, one of the important constants that determines the lubricating properties of an oil. More than a score of long letters and reports are prepared annually in reply to such requests. The Bureau accordingly

started several years ago to make an intercomparison between the

Saybolt-Univrsal, the Engler, and the Redwood viscosimeters, the

instruments most widely used in this country and abroad, with a view to preparing conversion tables that would enable technical men

to convert their results from the scale of any one to the scale of either

of the other two. More assistance should be available for the work.

Preliminary conversion tables for the first two of the aforementioned

instruments have been furnished to a number of technical men in the

reports above referred to. Low-Temperature Laboratory.

Considerable time of the working force of this laboratory has

been devoted to installation and operation of the carbon dioxide

refrigeration plant which is in daily use in connection with the

problems described under "Refrigeration constants," to the production of liquid air, when required for low-temperature tests, and

to the production of pure oxygen and hydrogen for use in the several

laboratories of the Bureau. Considerable work has been done in

overhauling the liquid air and hydrogen plant, and in the design

and construction of a new electrolytic generator for the production

of oxygen and hydrogen.

The Fire-Resisting Properties of Structural Materials.

This investigation has been organized during the year. Its scope

is so broad that it does not come within this division alone. The

planning and carrying out of the high-temperature measurements,
30 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

the fire tests of structural materials, the determination of their

thermal conductivities, etc., are receiving the attention of this division. The problems relating to the preparation and testing of concretes, tiles, bricks, steel structural material, etc., are receiving the

attention of the concrete, ceramic, structural materials, and chemical laboratories of the Bureau; the electrical features of the investigation, such as safety rules for electric wiring, problems appertaining to the national electrical code, etc., are being looked after by

the electrical division, while the behavior of these materials under

beat as to their expansion, etc., is being investigated by the division

of weights and measures. The present investigation serves as an excellent illustration of the

broad scope of an engineering investigation that requires the co- operation of nearly every one of the scientific and engineering

laboratories of the Bureau.

During the past year considerable time was devoted to the organization of the work, assembling of the necessary equipment, etc. One important investigation now well under way relates to the

behavior of steel and cast-iron building columns under fire conditions, when exposed and when protected by various kinds and types

of fireproofing. We are going ahead erecting buildings and accepting types of building construction, the integrity of which, in case of

fire, will depend entirely on the behavior of the supporting steel

columns. The building codes of different cities are entirely at

variance as to the amount and kind of fireproofing required. It is

therefore of the utmost importance that reliable engineering data

be obtained on these questions, which are now too much matters of

individual opinion. This investigation is being carried out in

cooperation with the underwriters and mutual laboratories.

Another important phase of this investigation, which it is hoped

will be gotten under way in the very near future, relates to the compiling of the various municipal building codes, not alone with a view

to furnishing information to cities and others interested along these

lines, but with a view to a comparative study of the codes to assist

in planning a systematic program of investigation to answer those

questions on which there are radical differences of opinion.

Testing.

A summary of the tests completed in this division during the year

is given below.

Over 1,100 mercurial thermometers of various kinds were submitted for test, of which 910 were certified. These tests included

many types of thermometers, such as low temperature, laboratory,

high temperature, calorimetric. Beckmann, clinical standards, hydrometer, and special thermometers. Among the thermometers

tested were included a number of working standards used by manufacturers to control the accuracy of thousands of thermometers put

on the market. There were included in these tests 273 calorimetric

and Beckmann thermometers intended for use in the determination

of the heating values of fuels and many high-temperature thermometers intended to control various technical operations.

Ten thousand and seventy clinical thermometers were submitted

for test, 90.7 per cent of which were certified and 9.3 per cent re- jected for various causes, such as excessive error, retreating of index,
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 31

defects in construction, difficulty in throwing back index. These

thermometers were submitted by the several medical bureaus of the

Government, State medical institutions, manufacturers, hospitals,

dealers, physicians, and individuals.

In addition to the above there were tested in the thermometer

laboratory six calorimetric platinum resistance thermometers intended for the measurement of the small temperature changes met

with in calorimetry with the highest attainable accuracy. These

thermometers, which were developed in the laboratories of the Bureau

and fully described in the Bulletin, are finding considerable use in

technical and university laboratories.

Of all the thermometer tests summarized above, about 50 per cent

were made for the public and the remainder for various technical

bureaus of the Government.

Two hundred and seventy-four standard combustion samples of

sugar, naphthalene, and benzoic acid were sent out during the year,

against 152 during the preceding year, thus attesting to the growing

demand for these samples for the standardization of calorimeters

used for the determination of the heating values of fuels, and to the

increasing practice of basing fuel contracts and specifications on

heating-value tests. The standard samples were furnished at the

cost of production to numerous industrial plants using large supplies

of fuel, such as cement, steel, cotton, and paper mills; coal, oil, and

gas companies ; electric-power companies ; chemical manufacturing

plants, etc.; to university, municipal, State, and national testing

laboratories and bureaus.

One gas calorimeter of the flow type and one combustion calorimeter of the bomb type were tested and certified. A number of care- ful determinations of the specific heats of analyzed samples of milk

and creams were made for the Bureau of Animal Industry. An ex- tensive series of tests of eight sample refrigerators, of four different

sizes, were made for the Office of the Quartermaster General, War

Department, as the basis for the award of large contracts. These

tests related to ice consumption, temperature distribution, and air

circulation within the refrigerators.

About 90 per cent of the calorimetric work was done for the public

and the remainder for various bureaus of the Government.

In the high-temperature laboratories there were tested 92 thermocouples (platinum and base metal), 3 platinum resistance thermometers, 7 total radiation pyrometers, 14 optical pyrometers, 17 pyrometer galvanometers, 10 special tests, 26 determinations of melting

points of refractories, such as fire and carborundum bricks, clays,

infusorial earth, lavite, blast furnace slags, iron ore mixtures, etc. These tests were 'submitted by a wide variety of interests, such as iron and steel plants and allied industries ; cement, gas, and ceramic

plants; electric manufacturing companies; manufacturers of high

temperature apparatus, and of watches, tools, springs, axles, automobiles, etc. ; technical and university laboratories, etc. There has been a very marked increase in the amount of testing

that the high-temperature laboratory has been called to do during

the past year, amounting to above 75 per cent over that of the preceding year, and these demands are steadily increasing, which is satisfactory testimony that American industries are rapidly substituting
32 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

careful pyrometric control of high-temperature operations for the

old method of eye estimation and other " hit or miss methods."

About 75 per cent of the high-temperature tests above summarized

were made for the public and the remainder for various technical

bureaus of the Government.

A rather comprehensive test of five electric stoves for heating

engravers' plates was made for the Bureau of Printing and Engraving. These tests included measurements of efficiency, of degrees of

uniformity of surface temperature, of rate of heating, etc., and were

made as a test for a compliance with specifications and as a basis for

the award of large contracts.

Two hundred and twenty-five samples of oils, inflammable materials, etc., were tested in this division. These tests were all made for

various bureaus of the Government, and tests include determinations of viscosities and flash points for compliance of lubricating

oils with specifications, or for their suitability for special uses, determinations of the flash and fire points of material's containing constituents that may make them dangerous in transportation on passenger

carrying vessels, etc.

Information Furnished, Reports, etc. An important feature of the work of this division has been the

information that has been furnished by means of letters, and often

quite lengthy reports, on subjects related to its lines of work. Several hundred such communications were prepared during the year.

The requests for information come from nearly every type of industry in which technically trained men are employed, from national,

State, and municipal laboratories and bureaus, from scientific investigators, and from committees of engineering and technical societies,

and relate to a wide variety of problems, such as, by way of illustration

Report on fire extinguishers for use on passenger-carrying ships;

Report on air conditioning equipment for the New York appraisers stores; Summary of scientific literature bearing on the experimental verification of

the radiation laws;

Report on the radiation constants of substances, collected from published

scientific literature;

The thermal constants of materials, the specific and latent heats of solid,

liquid and gaseous substances ; the melting points of metals, alloys, and refractories; the thermal conductivities of various materials, such as heat insulating

materials used for cold-storage construction, for steel-car construction, for

furnace construction, for steam-pipe covering, etc. ; the heats of combustion of

substances

;

Comparators, electric furnaces, etc., suitable for testing various types of

thermometers and pyrometers;

Metals and salts of known melting points for checking pyrometers in the

works

;

Method of high-temperature measurement best suited to particular industrial

requirements

;

Methods of determining various thermal constants such as specific heats,

latent heats, melting points, conductivities, radiating properties, etc., and refer- ences to the scientific literature bearing thereon;

Electric furnaces suitable for determination of fusing points of ash, ores,

slags, etc.; Method of applying the cold-junction correction to thermocouple readings

;

The temperature of the Bunsen flame;

Method of overcoming vibration of temperature measurements of instruments

in steel mills;
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 33

The softening temperature of Seger cones used in the ceramic industries

The making and burning of sillimanite and kaolin refractory tubes for use

in high temperature laboratory work

Radiation and convection from steam radiators ; the reduction in heat loss

from buildings by double windows;

Methods of calorimetric measurement; strength of bombs; use of standard

heat samples, etc.

The liquefaction of hydrogen ; the separation of oxygen from air, etc.

The definition of the British thermal unit, the calorie, etc.

Specifications for various types of thermometers;

Legal requirements as to the flash points of oils, inflammables, etc. ; methods

of measuring viscosities ; flash points found with different instruments ; specifications for oils. Technical and scientific men are constantly visiting the laboratories

to consult with the men engaged on various lines of work, and in

this way, as well as by correspondence, the work of the division is

brought into intimate relation with the industries it is intended to

serve. New Work, Equipment, and Personnel.

It is deemed more important that opportunity be provided to complete the investigations already under way in this division rather

than to take up any very extensive new lines of work, and yet there

are some very important technical problems that the division should

look forward to taking up within the next one or two years. These

problems will be briefly outlined below.

The routine work of testing, which this division has been called

on to do, has grown very rapidly, being over 50 per cent greater for

the j^ear just closed than for the preceding year, without any increase

in the working force. This has necessarily resulted in delaying, and

in many cases in stopping entirely, progress on important lines of

investigation. Additional assistance is urgently needed.

Standard Melting-Point Samples.

A number of metals and salts, of accurately determined melting

points, should be certified by the Bureau and supplied to technical

men to enable them to conveniently check the accuracy of their

pyrometers, just as the standard combustion samples now furnished

by the Bureau serve to check heating value tests. Numerous requests

have been received by the Bureau to furnish such standard meltingpoint samples. To meet this demand will require an outlay of about

$1,000 for a sufficient supply of materials to inaugurate the work and

about half of the time of a minor assistant. The fees received for

the standard samples would nearly, if not quite, pay for the work

and materials.

New Equipment.

A number of important items of equipment, which have been deferred from year to year, are urgently needed and should be provided

for, such as bomb calorimeters, electric furnaces, heavy current transformers and rheostats, thermocouples, radiation pyrometer, and re- fractory porcelain for high-temperature work.

65301°—14 3
34 REPORT OF DIEECTOB OF BUBEAU OF STANDARDS.

3. ELECTRICITY.

Equipping New Electrical Laboratory.

During the first half of the fiscal year the new electrical laboratory

was equipped with pipes, wires, switchboards, storage batteries, and

other necessary equipment, and the machinery and apparatus moved

in from the rooms in three different buildings previously occupied.

The large amount of time required for the moving and setting up

of apparatus has interfered to some extent with the work of research

and testing. Nevertheless, the results of the year show that a considerable quantity of both have been done.

Fundamental Electrical Standards.

The investigations upon the Weston cell as the standard of electromotive force have been continued. An intimate study of the

methods of preparing the chemicals used has revealed sources of

small variations hitherto unsuspected, and the cell as now made is much more constant in value and more reproducible than formerly.

Considerable progress has been made in the attempt to remedy the

cracking of the Clark cell, which has heretofore been a serious

defect of the cell. The work on the mercury ohm has been completed, and the re- port upon it will shortly be ready for publication.

The investigation on the silver voltameter has been continued and

two papers published during the year. One was Part IV of the

general investigation, and deals with the purity of the materials and

other questions affecting the accuracy of the standard, and the other

was a paper on the relation of the silver voltameter to the iodine

voltameter. This work is of great importance in permitting the

international definition of current to be specified with greater ac- curacy. Specifications for the use of the silver voltameter are being

prepared, based on the extensive experience of the Bureau.

Electric-Measuring Instruments.

The methods of testing potentiometers have been thoroughly investigated. New methods for carrying out these tests rapidly and

with the highest precision were devised and applied. These instruments are the fundamental means of accurate measurements of

voltage, current, and power, and their accurate calibration is important.

Transformer Formulas.

A study has been made of the formulas which represent the behavior of" transformers. The formulas in common use depend upon

certain assumptions and approximations, which had never before

been thoroughly examined. This work makes it possible to predict

with greater certainty the behavior of a transformer from its meas- ured characteristics.

Potential Transformers.

A simple method of testing potential transformers has been perfected. The method requires the use merely of wattmeters and other

ordinary instruments about a central station. Instrument transformers are in use in central stations where large quantities of
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 35

electric power are handled. It should prove of great use to have an

accurate method available of standardizing these important transformers which requires only apparatus of the most ordinary sort.

Sensitive Galvanometers.

The object of the investigation is to produce galvanometers which

are more sensitive and better adapted to the various needs of the

Bureau than are the galvanometers which are on the market. The

work will include the determination of constants and behavior of

instruments of different make; the study of the theory in the light

of the experimental data, and the development of a definite procedure for the design of instruments to have previously selected

values of operating constants.

Vibration Electrometer.

Another need which has been felt in alternating-current testing

has been met by the design and construction of a vibration electrometer. This instrument is capable of measuring extremely small

alternating currents, such as are used in the comparison of small

electrostatic capacities.

High-Frequency Instruments.

An investigation was made of the ammeters used in radiotelegraphy. Every radio station has one of these instruments for the meas- urement of the high-frequency currents used. In many cases they

are very unreliable. The sources of error were discovered by a rigid

theoretical and experimental research, and means were devised for

overcoming the errors and bettering the designs. Some of the work

strengthened the application of alternating-current theory to highfrequency measurements.

Decremeter for Radiotelegraphy.

The decrement or rate of decay of the trains of waves emitted by

radiotelegraphic antenna is limited by law. The inspectors of this

Department have the duty of enforcing the law, and there was heretofore no instrument by which the measurement of decrement could

be made with speed and accuracy. A decremeter was therefore designed which has proved itself to be very satisfactory in practice,

and which has been adopted by the War and Navy Departments, and

by the Bureau of Navigation of the Department of Commerce for

the use of its inspectors.

The Standardization of Electric Wave Meters.

It is proposed to set up standard circuits of known frequency in

order to show what conditions affect the precision of wave meter

measurements and to improve the accuracy of such measurements;

also to give typical examples of the behavior of various wave meters.

Inductance, etc. A study is being made of the effective resistance of copper-clad

iron and steel wires to obtain data concerning the electrical properties of conductors containing an iron core over a considerable range

of sizes, current strengths, frequencies, and magnetic properties.

Such data can only be determined experimentally, and no previous
36 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

work has covered the field. Such conductors are used commercially

in telephone, telegraph, and power transmission work.

Methods for measuring the inductances of very small resistances

were devised and tried out. These methods i-icrease the accuracy of

alternating-current tests at the Bureau and other standardizing institutions.

Properties of Dielectrics.

An investigation of the insulating properties of solid dielectrics

has been in progress for some years. The insulating materials used

in electrical work are many, and the accuracy of all electrical meas- urements depends on the reliability of the insulators. Hard rubber

and its many substitutes are the most important in the building of

electrical measuring instruments. A great many of those in common

use were tested for leakage of current through the material and

across the surface of the insulator. The effect of leakage across the

surface of these substances is tremendous, some of them having a resistance millions of times as great in dry weather as in damp

weather.

The Decrements of Coupled Circuits.

The object is to establish with greater certainty the formulas used

in the measurement of high-frequency resistance, to extend the known

formulas if possible, to find an expression for the errors in these

formulas, and to make available in English much material hitherto

in German only.

Magnetism.

Much work has been done on the relation of magnetic to mechanical

properties of steel. The steels investigated cover a considerable

variety of chemical composition and thermal treatment. Full-sized

steel rails are included in the investigation. It is hoped that the

information obtained will be of great value in the practical testing of

steel. It has been found that the permeability of ordinary steels

changes appreciably with temperature. This is under further investigation.

The study of core loss at the higher inductions has progressed

rather slowly owing to difficulties met in the determination of the

form of the wave of electromotive force. The bismuth spiral, well

known as a convenient means of measuring magnetic fields, has been

found to have several peculiar properties. Careful study of this is

in progress. These lines of work are of the greatest interest to

electrical engineers and to research laboratories.

Radium.

The intercomparison of sealed radium standards and the study of

the gamma-ray method of radium measurement have made satisfactory progress, and very accurate measurements are now regularly

made. Studies are being conducted of the alpha-ray activity of

powdered material, of the activity of uranium mixtures, and of

radium ores and radium emanation. The radium laboratory has

made numerous tests of specimens to determine the amount of radium

present, and hence the money value.
BEEOKT Or DIBECTOB OF BUREAU OE STAJSTDABDS. 37

Gas Photometry.

The pentane lamp as a working standard in measuring the

candlepower of gas flames has been under investigation for some

years. A paper on this lamp as a working standard was published.

The information given enables municipal inspectors, gas companies,

and others to obtain more accurate measurements than heretofore,

by taking proper precautions in the use of the lamp.

Flame Standards in Photometry is another paper published during the year. This gives results obtained on the Hefner and pentane

lamps with regard to their reproducibility and the effect of variations in atmospheric humidity and barometric pressure.

Color Photometry.

Considerable progress was made during the year on the difficult

problem of color photometry, i. e., measuring the candlepower of

lamps having widely different colors. One of the most convenient

methods is by the use of colored glasses to bring the lamps to a color match, but the calibration of these glasses must first be made.

The percentage of light transmitted by these glasses for different

colors and under various conditions was studied. The equations of

the curves expressing the relation between candlepower and voltage,

watts per candle and voltage, etc., have been derived for tungsten

lamps, and it is found that they apply very exactly for lamps of

different makes and even of., different methods of manufacture.

Their use will permit standard lamps to be used at any desired color or efficiency within a considerable range, and thereby avoid color

differences in measurements. The work is nearly ready for publication.

Effect of Atmospheric Conditions on Flame Standards.

A study is being made of the effects of atmospheric conditions on

flames, particularly to determine effects of barometric pressure and

of humidity on the intensity of the light emitted by flame standards

of candlepower and by. gas flames. The work will include photometric measurements on flames under varying natural conditions,

and similar measurements on flames in an inclosure to which a compressor furnishes air under high or low pressure, variations in

humidity being obtained by drawing the air through water or over drying material. Results so far obtained are of great interest and

importance, and the work will shortly be ready for publication.

Electrical Testing.

The following list of instruments and materials tested during the

year is arranged in six groups, corresponding to the six sections in

which the electrical testing is done. The more important tests for

the Government are so marked. The remainder are nearly all for

the public.

The following tests were made of standard cells, standards of

resistance, resistance apparatus, and electric conductivity of materials: 85 portable or unsaturated Weston cells, 4 saturated Weston

cells, 69 resistance standards, 9 shunts, for current standards. 3 volt

boxes, 4 potentiometers, 1 slide wire, 2 Wheatstone bridges, 3 resist- ance boxes, and 58 conductivity samples (42 for the Government).
38 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

The tests of inductance, capacity, radium, and radioactive sub

stances included : 19 electric condensers, 10 samples of telephone

cable, 15 inductances, 2 tests of insulation resistance, and 28 specimens of radium salts (aggregate value of the radium contained,

$58,000).

The tests of electrical measuring instruments, transformers, etc., included : 15 voltmeters, 19 ammeters, 7 wattmeters, 29 watthour

meters, 12 instrument transformers. 1 frequency meter, 56 dry cells,

4 primary cells, 24 wire samples, 2 porcelain spools, 178 pairs rubber

gloves (for the Government), 41 electric fans (for General Supply

Committee), 5 samples of insulating varnish, 7 telephone jacks, and

2 recording potentiometers.

Wavemeters, decremeters, high-frequency ammeters included: 4

wavemeters, 35 decremeters (for the Army and Navy and Bureau of

Navigation), and 2 high-frequency ammeters.

Magnetic materials were tested to the extent of 78 permeability

and hysteresis tests of iron, and 24 core loss in sheet iron.

Photometric testing, 109 electric lamps were tested for candlepower, and 1,800 tungsten and carbon filament lamps were tested for

life, and 1,092,549 tungsten and carbon lamps were inspected for the

various Government departments.

Other photometric tests included : 12 pentane lamps for photometric standards, 23 reflectors, 7 portable photometers, 2 arc lamps,

and 14 street series tungsten lamps.

Information Furnished on Electrical Subjects.

In addition to information furnished in connection with the va- rious investigations and tests, the electrical division has furnished

miscellaneous information on a great variety of subjects.

Requests have been answered for definitions of units from the

American Society of Mechanical Engineers, from the French Government committee on systems of units, and from editors and others.

There has been some difficulty in furnishing full information on the

electric units and standards, as there is no single, consistent compilation of data on this subject. Because of this fact, work has been

begun upon a circular treating the subject in a complete and thorough manner.

There are occasional requests for revision of physical tables. Considerable data were furnished for the Smithsonian Physical Tables,

for a special book of " Conversion Tables," and for other sets of

tables.

The numerous inquiries regarding electric measuring instruments

are in many cases answered by sending the inquirer a copy of the

Bureau circular on this subject. The many developments and improvements of the last five years in this field required a revision of

the circular. This has been done, and the circular is now thoroughly

abreast of the times and is a valuable compendium of information.

The Bureau has furnished considerable information regarding the

electrical constants of copper to the International Electrotechnical

Commission, through its American committee. The investigation on

the conductivity and temperature coefficient of resistance of copper,

which was conducted here in 1910, was considered a suitable basis for an international standard. Such a standard is useful for the expression of per cent conductivity, and in the preparation of wire tables.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 39

The question was considered by international committees and by the

committees of various national engineering societies. Information

was sought from the Bureau at all stages of this consideration. Besides furnishing the data asked for, the Bureau prepared a very complete set of copper-wire tables, with explanations and historical discussions of the allied subjects.

This work culminated in the adoption of the values upon which

our tables are based as international standards. This action was

taken by the International Electrotechnical Commission in plenary

session at Berlin in September, 1913. The circular on this subject

has since then been revised and a new edition prepared. The new

copper standards have been adopted in the 1914 Standardization

Rules of the American Institute of Electrical Engineers. The British engineering standards committee also has taken up the work of

revising its tables to bring them into conformity with the international standard. This is the first time that the electrical engineers

of all nations have had a common standard for copper. Following

the international adoption, there was considerable correspondence

with the commission and with the other national standardizing laboratories to settle certain questions regarding the numerical values.

In the revision of its standardization rules, some assistance has

been rendered the American Institute of Electrical Engineers. This

assistance includes the furnishing by the Bureau of the material for

the new section on wire and 'cable standardization. There was considerable discussion and correspondence regarding some of the definitions, and two discussions of certain provisions of the rules were

published in the technical press by members of the division.

Some inquiries on the definitions of units of force and power have

arisen as a result of the Bureau's circular on horsepower. These

have led to a thorough revision of said circular, with the addition

of discussions of the units of force and standard values of gravity.

There have been numerous letters asking the Bureau to pass an

opinion upon pseudoscientific discoveries and inventions. Men of

limited education or equipment who believe they have made wonderful and revolutionary discoveries often possess extraordinary confidence in themselves and their work, and it is exceedingly difficult

to convince them of the fact that some things are definitely known

to be impossible. The Bureau has, however, been able to render some

service to the public by replying to inquiries concerning the worth of

some of these schemes, especially those in the perpetual-motion class.

Investigators and radiotelegraphic companies have sought information on the calculation of inductances. Some of these inquiries

could be answered by reference to our Bulletin articles on the subject,

while others required some independent work.

In the field of radiotelegraphy, the Bureau has been called on for

considerable information. Assistance has been rendered the Bureau

of Navigation of this Department on questions relating to the

measurement of wave length and decrement, interference caused

by arc stations, and transmitting and emergency sets. As a result

of our advice on the latter subject, the ships equipped by certain

commercial companies have discarded the emergency sets formerly

used and adopted others, based on the methods suggested. Information has been furnished regarding the radio equipment of small

boats such as revenue cutters, and of lighthouses for fog signaling.
40 REPORT OF DIRECTOR OF BUREAU OP STANDARDS.

Amateurs have sought information regarding the legal regulations

and regarding operating questions. These inquiries make it appear

that a general circular of information on radiotelegraphy for amateurs and others would be very desirable, and the preparation of such

a circular is projected for the coming year.

The work already done on sensitive galvanometers has made it possible to furnish information to various investigators as to the

construction of very sensitive instruments for special purposes.

There have been many inquiries regarding the testing of radium

and of radioactive waters and allied questions.

In magnetism there have been requests for typical data on the

magnetic constants of various grades of steel used for electromagnets and permanent magnets. Reliable data on these matters would

be very valuable, but have never been collected from the abundant

literature. The necessary time has not yet been found to take it up

systematically.

Information has been furnished as far as available in the subjects

of street-lighting specifications, headlights and projectors, and illuminating-oil specifications.

Public-Utility Investigations.

The above statements of investigations completed or nearly completed, of publications, of testing, and information supplied to the

Government and the public, covers in large part, though not completely, the work of the electrical division, which consists principally

of laboratory work and testing. The remaining work has to do

largely with "public-utilities service, and consists of scientific and

engineering researches, the study of public-relations questions, and

the collection and distribution of information. This work may con- veniently be described as follows under separate headings.

Service and Standards for Illuminating Gas.

This work has been carried on for several years under the direction of the electrical division, with the cooperation of other divisions

of the Bureau, especially the chemical and heat divisions. Regulations for gas service, as made by cities or State commissions, include

among other things the requirements as to meter accuracy and the

testing of meters, the specifications of the heating value or candlepower of the gas (or both), the degree of chemical purity as ex- pressed by the limits set to the amounts of sulphur and ammonia

that are permitted, the variations in pressure that may be allowed,

and the manner and frequency of tests to determine whether the

operating companies conform to the requirements.

In addition to invstigations carried on by the Bureau for the past

five years on these subjects, which have resulted in a considerable

number of papers published in the Bureau's scientific and technological series, a thorough study was made of the rules and regulations of cities and States, and a thorough discussion made of the

subject in Bureau Circular No. 32, first published three years ago.

This was revised and republished a year ago and is now being revised

for its third edition. This publication has had a wide circulation

and serves a useful purpose in setting forth the proper basis for

regulations, discussions as to the relation between the quality of gas
REPORT OF DIRECTOR OP BUREAU OF STANDARDS. 41

and the efficiency of manufacturing processes, and the most satisfactory terms of specifications of quality and methods of testing.

Another publication which will shortly be issued is Circular No.

48, which will give a detailed technical discussion of methods of gas

testing. This will be the joint work of several divisions of the

Bureau.

The Bureau has given assistance to a considerable number of State

commissions and cities in connection with the adoption of ordinances

or orders regarding gas service, and has sent a representative to a number of public hearings conducted by State commissions. It is

of much importance that the regulations and requirements of the

several States and cities shall be as uniform as consistent with progress and justice to the companies and the public. The Bureau aims

to serve in some measure as a clearing house of information on many

of the scientific and public relations questions arising in connection

with the regulation of gas companies, and to be perfectly impartial

as between the companies and the public.

Another important work in which the Bureau hopes to do more

during the coming year is the inspection of testing laboratories and

equipment, both of companies and the public, with a view of getting

information for our own use and of giving suggestions or information that would improve the accuracy or efficiency of the testing.

The information secured would be used in connection with publications on laboratory equipment and testing methods. It would en- able the Bureau to keep in closer touch with the industry and the

regulating bodies that represent the public and to give more valuable

information when called upon.

One of the most important and at the same time difficult questions

for a regulatory body to decide is the quality of gas that shall be

specified. Gas is measured by meters, which register in proportion

to the volume of gas passing, expressed in cubic feet. This volume

of a given mass of gas varies according to its temperature and pressure, the latter varying with altitude above sea level. It is its mass

or effective quantity that determines its usefulness, rather than its

volume merely, and hence some very complicated questions arise

when one attempts to prescribe how it shall be measured and tested

and be fair and just both to the company and the public. The Bureau has discussed these questions fully in its publications, and has

recently carried out some extensive measurements on the variation

of the light of pentane and Hefner standard lamps with atmospheric

pressure, and the variation of the luminous efficiency of gas flames

with the pressure of the atmosphere.

Electrolysis Mitigation.

The greater portion of the street railways of the country are operated on the single overhead-trolley plan, with the electric current

flowing into the rails through the car wheels, after it has passed

through the car motors. The current then flows back to the generating station or substation by way of the tracks and earth, much of

it, however, often flowing through underground gas and water pipes

and the lead sheaths of underground telephone and electric light

cables, and sometimes through reinforced concrete structures. The

earth conducts electricity by virtue of its moisture and the salts

dissolved in it, which renders it an electrolyte. Hence, when the
42 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

electric current flows away form iron pipes or lead cable sheaths,

it carries away iron or lead, by electrolytic action, and this in time

often eats holes into the pipes and sometimes completely destroys

them.

The trouble is the more serious in places where the soil has a greater conductivity than usual, and also where the car tracks are fewer in proportion to the current, and the distance the current

travels back to the stations is relatively great. Many remedies have

been proposed and tried, but no standard practice for the. handling

of the return current has ever been agreed upon in this country. As

the electric railways have been extended and traffic has become

heavier, the volume of current handled has increased very greatly,

and the destructive effects of these currents, which are cumulative

with time, have become increasingly evident. In some cases litigation has resulted between the pipe-owning companies suffering

damage, and the railway companies whose current caused the trouble.

But although the courts have considered the question of legal re- sponsibility, these cases did very little to prevent the trouble in an

effective and economical manner.

The Bureau has been studying the question for the past four years,

and has done a large amount of work in connection with it. This

has included laboratory investigations concerning the effects of electric current on concrete and metal pipes, tests of pipe coverings, the

corrosion of metals in the soil, methods of measuring soil resistance

and various other experimental phases of the work; methods of

electrolysis mitigation that have been used or proposed and the re- sults obtained; field studies in actual practice with the application

of remedies and a determination of the cost and results obtained.

During the past year work was done in St. Louis, Springfield, and

Elyria, Ohio, and Springfield, Mass., and reports prepared, some of

which were published during the year.

The recent electrolysis survey in Springfield, Mass., was made at

the invitation of the city of Springfield, and most of the publicutility companies of the city, including the gas, electric light, telephone and telegraph companies. The railway company did not

unite in the invitation, but gave the engineers of the Bureau free access to its property and full information regarding its currents,

cables, and station operation. The cost of the survey and the report

is borne in part by the Bureau and in part by the utilities. The

object of the work is not merely to benefit Springfield, but to demonstrate the method of procedure in making electrolysis surveys, and

in securing relief from electrolytic corrosion in an efficient and eco- nomical manner.

This work will be continued during the coming year, and it is hoped that the Bureau's work will induce railway, gas, and water

companies generally to make electrolysis surveys, and the railways

to giving more attention to bonding of tracks and the provision of

adequate return conductors for their current, so that less current

will get into gas and water pipes and cable sheaths.

The work of the Bureau has been received most favorably by many

railway officials and engineers, but very many still feel that it is a hardship to provide adequate conductors for the return current,

having for so long been accustomed to turning it loose in the earth

to return as best it could.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 43

The following technologic papers on this subject were issued during the year:

Surface Insulation of Pipes as a Means of Preventing Electrolysis (No. 15). an experimental study of a great number of pipes, coatings, and wrappings,

and the effects on the electrolytic corrosion of underground pipes.

Electrolytic Corrosion of Iron in Soils (No 25), a study of the effect of cur- rent density, moisture, temperature, and oxygen upon the corrosion of pipes,

and the bearing of the results obtained upon electrolysis mitigation in practice.

Special Studies in Electrolysis Mitigation, No. 1 (No. 27), a preliminary study

of conditions in Springfield, Ohio, with recommendations for mitigation.

Special Studies in Electrolysis Mitigation, No. 2 (No. 32), an experimental

test on a system of insulated negative feeders in St. Louis.

Electric Light and Power Service.

During the past year we have been studying the question of the

specifications of electric light and power service, and the requirements that should be made by cities or State commissions of publicutility companies furnishing such service. This study is similar to

the studies described above concerning gas service for heating and

illumination. The principal factors of such service are its quality

and reliability, and the accuracy of the meters that measure it. Steadiness of voltage, without which electric lighting is not satisfactory, and continuity of service are phases of quality that have

sometimes been included in regulatory ordinances, while the permissible errors of meters and frequency of testing of the same are almost

always included. As the requirements that can fairly be made vary

under different conditions, and as there has been relatively little ex- perience so far in the enforcement of some of these requirements,

there is ample room for study by the Bureau, this study including

consultation with a great many operating companies and the collection of results obtained under various kinds of regulatory ordinances.

The feasibility of making requirements of this kind in the case of

the smaller utilities is a question deserving careful study. The

extent to which automatic voltage regulators, recording voltmeters,

pressure wires and instrument and meter-testing outfits can be

utilized by such small companies without undue hardship, and possibly a resulting detriment to their customers, is a question of great

practical importance, and we are planning to give considerable attention to it during the next fiscal year.

During the past year the Bureau answered many inquiries for

information, assisted cities and commissions in preparing regulations,

while a representative of the Bureau has conferred with numerous

companies and commissions regarding the questions we are studying.

Here, as in other lines of our public-utility work, we aim to serve in

some degree as a clearing house of information, although this work

is so recently established that it has so far made only a beginning.

An increased force is much needed to strengthen the work.

Life Hazard in Electrical Practice.

For many years the National Fire Protection Association has

studied the question of fire hazard due to electrical apparatus and

machinery and conductors carrying electric currents, and the underwriter's code, prepared and frequently revised by this association,

has been generally adopted and enforced in order to reduce the fire

hazard. But there has been no national body doing a corresponding
44 REPORT OF D1KECTOK OF BUREAU OF STANDARDS.

work to reduce the life hazard, while the number of serious accidents

and fatalities to linemen and other employees and the public has

been increasing year by year.

The matter became so serious that the Bureau secured from Congress authorization and a special appropriation to study the question.

During the past year this study has been in progress, with a view to

preparing safety rules to be observed in the construction and operation of electric light and power plants, and in the distribution and

utilization of electricity. Attention is given also to the fire hazard,

and in this we are cooperating with the underwriter's laboratories and

the National Fire Protection Association. The first set of rules on

the operation of electrical equipment and lines has been completed,

with the cordial cooperation of many electrical companies and public

bodies, such as State public-service commissions and State industrial

commissions. It is expected that these rules will be widely adopted,

and will tend to reduce accidents and assist in securing a much

desired uniformity of practice among the different States.

An interest has been awakened throughout the country in the

question of greater safety, and the work of the Bureau in the more

technical aspects of this safety movement so far as the electrical

industries are concerned, is very timely. The public is vitally con- cerned, also, for the use of electricity is so general, both in the

household, in the industries, and in transportation, and its distribution circuits form such a network in most communities that one

can not know when he is free from danger unless there is close

public supervision both as to construction and operation. Effective

supervision requires adequate and carefully prepared rules or specifications that can be readily understood and intelligently followed.

This work will be continued and enlarged during the next fiscal

year by the addition of another engineer to the two already en- gaged in this work.

Illuminating Engineering.

Provision is needed to enable the Bureau to take up in an adequate manner the many urgent problems in illuminating engineering. The lighting of streets and public spaces, public buildings and

auditoriums, stores, factories, and private homes is a matter that

is receiving a great deal of attention in recent years, and a great

many new and improved methods, as well as fixtures and appliances

for the purpose have been developed; but reliable information as to

the value of much of this material is hard to obtain.

The claims made by manufacturers are often conflicting, and

there is great need for an unbiased agency, such as the Bureau of

Standards, to make photometric and other tests and to determine

the performance of the appliances that are on the market. For the use

of the Government, States, and cities alone such information would

be of great value, but it would also be of immense value to the general public, and particularly to architects and contractors who are specifying and purchasing such appliances. We know also from

tests that we have made that improvements at practically no cost

could often be made if the necessary information were available.

The subject is a highly technical one and directly in line with the

Bureau's work, and a moderate, appropriation would yield valuable

results.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 45

Radiotelegraphy Research Laboratory.

One of the important needs of the Bureau is appropriate space for

research in radio communication, or wireless telegraphy, as it is

usually called. For several years the Bureau has afforded space and

experimental facilities to the Army and Navy for certain of their

investigations in this subject, and has itself done some research

work of this kind besides doing testing of instruments used in wirejess measurements. But with the rapid development of wireless,

the increase in the power used and the distances reached, and especially with its general use at sea for all kinds of service, the small

space and meager facilities that can be spared are entirely inadequate.

To meet the present needs as to space and experimental facilities, a separate building with special facilities should be provided.

An estimate was submitted last year for $50,000 to erect such a

building, but the appropriation was not made. It is recommended

that this item be again included in the estimates for the coming year.

It is proposed to locate this laboratory directly south of the electrical

laboratory, connecting it by a pipe and wire tunnel, so that the ex- perimental machines and sources of current of the electrical laboratory shall be available. This building would provide accommodations for the work of the Army and Navy that has been located at

the Bureau for several years. In addition to the sum estimated for

the building, an additional sum will be needed later for apparatus

and equipment.

Additional Facilities Needed.

"With the additional space afforded by the new electrical laboratory

building, the electrical division is now in much better condition to

do its work than heretofore. Owing to the pressure of testing,

however, the research work in some lines has suffered in recent years,

and it is hoped that several additional assistants can be provided.

In the matter of absolute electrical measurements, in which the

Bureau has done conspicuous work in the past, there is needed an

additional force to replace those drawn off to do other work for

which there was urgent demand. Considerable new apparatus is also needed to make the equipment satisfactory for the work to be

done.

The sum available for work on public-utility problems should be

increased, to enable the work to be done better and to permit taking

up some phases of the work not so far touched.

4. OPTICS.

Determination of Standard Wave Lengths.

The determination of standard wave lengths of light throughout

the entire spectrum is at present confined to fundamental work that

must be done before wave lengths can be accurately determined.

This is being done by the Bureau, in accordance with the recom- mendations of the International Solar Union, a body whose membership comprises the greater part of the eminent spectroscopist of the

world. While the results are needed mainly by scientists, they are also

necessary in the industries. For example, the spectroscopic analysis

of steel and other substances can not be successfully undertaken until
46 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

the characteristics of the spectra of the constituents are more accurately observed. This requires wave lengths of standard or known

values. The instruments necessary for carrying on this investigation have been designed during the past year. That part of the

apparatus necessary for the work in the ultra-violet part of the

spectrum has been constructed and found to be satisfactory. The

mounting of a concave grating spectroscope is in progress. About

one-seventh of the measures of standard wave lengths have been

completed.

Spectroscopic Testing.

Spectroscopic tests have been made of the transmission of glass

for the ultra-violet rays, mainly with a view to determining their

fitness for spectacle making. Assistance has been rendered to several departments of the Government and to various individuals and

firms. Spectroscopic measurements are becoming more and more

important, not onty in scientific work but in illuminating engineering, the testing of materials, and industrial processes. Such tests are often useful to determine the presence of elements in very minute

quantities. With the new grating spectroscope it will be possible to

take up this work more effectually.

Standard Samples of Pure Gases.

There have been several demands for standards of pure gases.

While the spectroscopic division will soon be able to test the purity

of gases, it is not yet feasible to undertake to furnish gases in a state

of sufficient purity to serve as standard samples.

Polarimetry.

The polariscope and its accessories are the indispensable adjuncts

of the refined-sugar manufacturer, the beet and the cane sugar

planter, public sugar chemists, and the customs sugar laboratories.

In addition, they are part of the regular physical and chemical equipment used in other industries as well as institutions of learning. The

importance of the investigation and standardization of this apparatus

has seldom been appreciated by other than scientific workers; it has

been found necessary to discard many of the results and methods of

the past. In addition to a common basis of standardization, a unification of methods "is necessary if the results of different laboratories are to be brought into agreement. During the past year a circular

(No. 44), entitled "Polarimetry," has been completed and given a

fairly wide distribution among workers in this field. This circular

describes approved methods of polarimetric analysis, and shows improved types of apparatus, some of which have been developed at the

Bureau.

Conference of Polarimetric Experts.

The general interest aroused in polarimetry by the distribution of

this circular has suggested the calling of a general conference of

those interested in polarimetric work. . The numerous troublesome

questions arising from differences in methods would be discussed and

probably eliminated. There would also result a wider dissemination

of information relative to the standards adopted by the Bureau than

could be secured in any other manner.
EEPOET OF DIRECTOR OF BUREAU OF STANDARDS. 47

Influence of Atmospheric Conditions in the Polarimetric Testing

of Sugars.

A research of importance to the sugar industry, and of considerable theoretical moment, has been completed on the influence of

atmospheric conditions in the polarimetric testing of sugars. The

influence of atmospheric conditions on the testing of sugars has not

been well understood, owing to the difficulty of controlling both

temperature and humidity in the research laboratory. Relatively

large and inexplicable differences have been noted for some time

between the tests on imported sugars for the collection of duty at the

various ports of entry. So great have been these differences that it is probable that sugars have purposely been imported via certain

ports with the intent of paying a lower rate of duty. The Bureau's

investigations not only shows the exact cause of the differences, but

also a simple and certain method of eliminating them.

Study of the Basic Lead Acetates.

Another polarimetric investigation consisted of a study of the basic

acetates of lead used for the clarification of the opaque solutions of

raw sugars for optical analysis. This research has covered ground

which is essentially new and has shown what basic acetates of lead

may exist and what is their behavior in aqueous solution. It has

been shown that most of the previous work on this subject is in error. Determination of the 100-degree Point of the Saccharimeter.

This research has been under way for several years, and the results are now being prepared for publication. Being essentially precision

measurements of fundamental constants, the greatest care is being

exercised to insure the accuracy of the values. By this investigation

the Bureau has established the most important fact that the basis of

calibration of the saccharimeter (a particular form of polariscope)

.

used the world over in sugar analyses, is in error by over one-tenth of

1 per cent, resulting in a considerable loss to the Government in

duties collected on imported sugars and, in addition, the producers

of raw sugars have received less compensation than they should have

received.

Precision Polariscope.

The large polariscope designed and built by the Bureau for magneto-optical work has been tested and found satisfactory. This equipment now constitutes an invaluable auxiliary for the study of optically active substances, as well as substances not in themselves active,

and has opened up a large and important field for investigation.

Preparation of Standard Sugars.

The work on the preparation of dextrose has been continued and

standard samples have been issued. This substance which is prepared

in the laboratory from the crude glucose is intended as a standard

to assist in bringing about uniformity of analysis of a class of substances known as reducing sugars. The investigation of dextrose will

be continued. Fifty-eight standard samples of sucrose and seven samples of dextrose were furnished to the public.

Another substance which occurs in sugar mixtures to a slightly

less extent than dextrose is levulose. The rotation of this substance
48 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

has been but little studied, although its frequent occurrence necessitates continual use of such data as exist. The pure substance is prepared with very great difficulty, but a considerable quantity has been

prepared, and during the ensuing year the Bureau will be able to

begin the measurements upon it. Supervision of the Customs Service Sugar-Testing Laboratories.

The important changes made a year ago, including the introduction

of the bichromate light filter and the improved polariscope tube, have

given excellent results, and the systematic differences existing between the tests of the various ports of entry have grown less. Protests on sugar entries have practically been eliminated.

The Bureau cooperates with the Customs Service in all matters

pertaining to the weighing, taring, sampling, and polarization of

imported sugars and molasses. The regulations governing the polarimetric work of the Customs Service, and which were prepared in

cooperation with the Bureau, are given as an appendix in the polarimetric circular.

Polariscopic Testing.

During the year approximately 1,500 polarizations of sugar were

made principally in connection with the control samples sent daily

from the various ports of entry for sugar.

Interferometry.

By interferometry is meant measurement of length where the principle of interference of light is applied and where light waves of a particular length are used as a working standard. This method is susceptible of great accuracy, and is particularly adapted to the

measurement of very small lengths or changes in length. By it,

changes as small as the one-millionth of an inch or even smaller may

be measured under favorable circumstances. Important applications

are now being made at the Bureau as given below.

Expansion of Materials Due to Temperature Changes.

New apparatus has been designed for temperature control and

regulation in measurement of expansion of small samples (a few

millimeters, i. e., less than one-half inch), by interference methods.

This apparatus was nearly ready at the end of the year. Measurement of the expansion of small samples from steel in connection with

the investigation of properties of rails was pending at the close of

the year.

Planeness and Parallelism of Surfaces.

A number of tests of planeness and parallelism of optical surfaces

and gauges have been made by means of interference methods. The

high degree of accuracy required in optical work of this nature can

only be secured by the use of this method. It is no unusual matter

for the optician to work to the one-hundred thousandth part of an

inch or less in the preparation of plane surfaces, which are often*

quite as essential as a lens in the optical system of an instrument.

Determinations of the Optic Axes of Crystals.

The determination by interference methods of the direction of

the optic axis, in quartz plates, such as are required for standards in
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 49

sugar analysis, color specifications and expansion measurements, has

now been reduced to a satisfactory routine. A number of plates,

most of which were constructed in the Bureau's optical shop, have

been tested.

Specification and Measurement of Color.

The investigation of methods of specification and measurement of

the color of cottonseed oil, undertaken at the request of the Society

of Cotton Products Analysts, has been continued. Extensive tests of the applicability of the quartz colorimeter to this problem were

made in cooperation with that society, and an instrument was

designed and constructed at the Bureau for use in this connection.

The investigation of methods of specifying the color of butter

and oleomargarine has been continued at the request of the National

Dairy Union, and the Dairy and Food Department of the State of

Minnesota. A new method has been devised which it is expected will

simplify and facilitate the specification of the color of these particular substances. Some tests of this method were made, and the

results communicated to the National Dairy Union. Preparation

has been made for carrying out further tests in cooperation with

the Dairy and Food Department of Minnesota.

An investigation of rosin colors and proposed standards for the

color of rosin has been undertaken at the request of the Bureau of

Chemistry of the Department of Agriculture. Partial reports have

been made and the work was in progress at the close of the year.

The question of color standards, the specification of color and

color measurement, is of such pressing importance to so many industries—such as paper making, lithography, ceramics, textiles, dairy

products, paints, oils, dyes, inks, and others—that a special appropriation should be procured to enable the Bureau to expedite this

work, which can only be taken up in a limited way with the present

staff and equipment.

Colorimetric Testing.

Tests involving about 25 different samples and several thousand

observations by different observers have been made in colorimetry

and spectrophotometry. There has been a marked increase in the

demand for tests of spectral transmission, i. e., the relative transmission of substances for light of different wave lengths. Tests of

this kind have been made for glass manufacturers, opticians and consulting engineers. Three pairs of smoked glass photometric wedges

have been calibrated for the Johns Hopkins University. Extensive

tests of the color of oleomargarine have been made for the National

Dairy Union.

Information as to Color Specification and Measurement.

Information relative to the specification and measurement of color

has been given to many individuals and firms, as well as to the Society

of Cotton Products Analysts, the National Dairy Union, the Bureau

of Chemistry of the Department of Agriculture, and to the American

Society for Testing Materials. A color screen of prescribed properties designed to reduce sunlight to skylight was prepared and tested

at the request of the Weather Bureau.

65301°—14 4
50 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

Color Blindness.

Some attention has been given to methods of testing for color

blindness and defective color vision. This question is now of pressing importance to the Bureau in connection with the observers in

colorimetry and photometry.

Turbidimetry.

To meet a long-felt need for a more precise standard of turbidity,

especially in water analysis, a new instrument for measuring turbidity, known as a " turbidimeter," has been designed and constructed.

It has been found satisfactory, and extremely sensitive. An improved instrument is being made which will be suitable for use in

standardizing the turbidity not only of liquids, but of gases and solid

plates.

The committee on the revision of the standard methods of water

analysis, of the American Public Health Association, and the American Chemical Society, have asked the Bureau to cooperate in the

revision of the standard of turbidity. An adaptation of the turbidimeter is being planned to be used in the study of fog as a part of

the work of the international ice patrol.

Transparency, Translucency, Diffusion.

Methods have been developed and put into practice for testing of

transparency, translucency, and opacity of materials, such as glass,

paper, and tracing cloth. There has been a marked demand for such

tests. Tests of this kind have been made for the Post Office Department and the Customs Service, and for firms or dealer's in tracing

cloth.

Tests of the distribution of light transmitted by skylight glass were

also made.

Investigation and Design of Optical Systems.

The essential feature of many optical instruments often consists

of a system of lenses, mirrors, prisms, or other optical parts. The

investigation, design, and testing of these optical systems forms one

of the principal lines of optical work in the Bureau, as such instruments are in very general use, both in scientific work and by the

public. Microscopes, telescopes, field glasses, and photographic

lenses are examples.

Apparatus has been designed and constructed for the purpose of

obtaining the axial light transmission of optical instruments. This

transmission is the ratio of the light which actually reaches the eye.

to that which would reach the eye through an exactly similar instrument composed of ideal lenses having no loss either by reflection or

absorption. The principal application of these measurements has

been to telescopes of all kinds, especially those intended for use under

exacting conditions of light. Some have been found which transmitted much more than others, and the indications are that such

instruments will be improved in this respect.

The determinations of the secondary standards of wave lengths

require the use of a special spectroscope giving good definition along

a spectrum line instead of across the line as in the usual types. The

optical system of such a spectroscope has been designed and com-
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 51

putecl. The system is composed of quartz and rock salt and gives a

flat field over a long region of wave lengths in the ultra-violet part

of the spectrum.

The design of a special photograph lens having a large flat field

has been undertaken for astronomical purposes.

Testing of Optical Systems.

The testing of optical systems has been done largely for the different departments of the Government. These tests embrace the

various types of optical instruments, including microscope objectives,

refr-ictometers, photographic lenses, telescopes of all kinds, binoculars, and various minor optical instruments. Considerable improvement in the optical quality of instruments has been noticed since this

testing has been carried on. For example, the magnification was

frequently found to be marked wrongly by at least 15 per cent,

while at present the error rarely exceeds 3 per cent. Other points

have been improved, especially where the defects were not easily

apparent in ordinary use, such as light gathering and definition.

Considerable time has been devoted to consultation work with the

various bureaus of the Government, as well as the different divisions

of this Bureau, in reference to the design, specification, testing, and

use of optical instruments.

Refractive Index.

Eefractive index determinations are used frequently in place of

chemical analysis when a mixture is known to be composed of two

compounds, but their ratios are unknown; also as a test of purity

where additions of adulterants produce a decided variation. In

order to rapidly determine these refractive indices, refTactometers

are used, and these must be calibrated and should be checked at intervals. For this purpose an investigation is in progress for the

purpose of ascertaining the permanence of certain oils which may

prove satisfactory for standard refractive indices. These oils were

accurately determined after special aeration and carefully bottled.

Another determination will be made at the end of about 12 months.

Attempts have been made to prepare standard samples of glass

which are required for the calibration of other types of refractometers. The difficulty lies in obtaining glass sufficiently homogeneous, two samples take from the ends of a bar of the best plass

only 8 centimeters long differed by 12 units in the fifth place.

A preliminary study has been made of the best methods of determining refractive indices from the viewpoint of both accuracy and

rapidity as well as the value of these determinations in the arts and

sciences.

Testing of Materials for Refractive Index.

Six samples of standard turpentines and two samples of Chinese

wood oil were secured from the American Society for Testing Materials, and the refractive indices of these samples were determined

at 15°, 25°, and 35° C, as well as the specific refractions. This work

was done in conjunction with the general investigation carried out

by the other divisions.
52 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

Tests have been made of the refractive indices of solids and liquids, change of the index of refraction due to changes in temperature, strains in optical glass, and other tests of minor importance.

Radiometry.

Measurements of the energy transmitted by radiations, of which

light and radiant heat are types, enter into many scientific investigations, both as to the nature of such energy and as to the properties of materials. They are of great importance, not only in physics and chemistry, but also in physiological investigations. During

the past two years investigations have been pursued with a view to

obtaining uniformity in radiometric measurement. The Bureau

has developed instruments, methods, and standards of radiometry

which are giving a new impetus to investigations in this complicated

field of research and measurement.

Numerous instruments for measuring radiation (thermopiles)

have been designed to meet various requirements; for example, one was designed suitable for delicate physiological investigation in nerve and muscle reaction. A new vacuum radiometer was designed suitable for the measurement of the radiant energy from

stars. This involved the development of a convenient method of

maintaining the thermoelement in a vacuum. This was done by

means of metallic calcium which rapidly absorbs the air contained

in the radiometer, thus avoiding the use of the ordinary heavy

air-pump equipment.

Nocturnal radiation is usually a loss of heat from terrestrial substances into space. A radiometer was designed for the United

States Weather Bureau for investigating this nocturnal radiation.

A paper has been prepared on the latest developments in instruments

and methods of radiometry. In it are given various improved modifications of the bismuth-silver thermopile which have been developed

in this Bureau.

Standards of Radiation.

The Bureau has established standards of radiation in the form of

incandescent lamps. In these standards the intensity of the radiant

energy per unit area at a unit distance from the lamp, has been established in absolute value, first, by comparison with a black body in

which the coefficient of radiation was assumed, and second, by direct determination of the intensity of the radiant energy in absolute

value. The two methods gave values which are in agreement within

0.5 per cent. Hence, the standard of radiation as defined by these

incandescent lamps may be considered well established. That they

will supply a long- felt need is evidenced by the fact that copies were

at once ordered by experimenters in this country and abroad.

Measurements were also made on subsidiary standards, including

the Hefner lamp and the sperm candle. The results are embodied

in a short paper submitted for publication.

Stefan-Boltzmann Constant.

Considerable progress was made in the work on the coefficient of

total radiation commonly called the Stefan-Boltzmann constant.

With the instrument used in establishing the above-mentioned

radiation standard, measurements were made on the total radiation
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 53

from a uniformly heated inclosure, or so-called black body. The

value obtained for this constant (a=5.6XlO-12 watt cm ~ 2 deg _4

) is in excellent agreement with previous determinations by other

methods.

Absorption Constants of Quartz.

During the year an investigation was completed on the absorption

constants of thick cylinders of quartz. The data are to be used in

furthering the work on the constant of spectral radiation of a black

body. The results are embodied in a paper now in press.

Radiometric Testing.

There is but little of the so-called routine testing in radiometry.

The tests that do arise usually require a very considerable amount of

original research. Several such tests were completed during the past

year. One was concerned with incandescent lamps giving a standard spectral energy curve in the visible spectrum ; another involved

the question of the quality of the radiation from a straight and a spiralled filament of tungsten in a nitrogen-filled lamp; also, the

determination of the spectral energy curve of this type of lamp in

the visible part of the spectrum, when the lamp is under normal

operation.

In conclusion, it may not be out of place to call attention to the

desirability of pursuing scientific investigations, even though at the

time they may not appear to have a direct commercial application.

For scientific purposes the Bureau made an investigation to find a substance which completely absorbs all the infra-red or heat rays

(which amounts to about 95 per cent of the radiations from the electric arc lamp) and at the same time transmit a maximum amount of

the light. It was not anticipated that such data might be useful in

safeguarding life and property in the most common present-day form

of amusement and entertainment. In reply to an inquiry by a manufacturer for an absorption screen to protect the moving-picture film

from the intense heat of the projecting lamp, this Bureau was in a position to give intelligent advice in this matter, based upon firsthand information which, at the time it was obtained, did not appear

to have any special commercial application. Many such illustrations

might be given.

5. CHEMISTRY.

Standard Analyzed Samples.

There is a growing tendency in commercial and Government circles

to base purchases of material on chemical analysis. Analytical operations are, however, all affected by errors, due to a variety of causes,

which the utmost skill and care on the part of the operator can not

altogether eliminate. By the use of certain of the Bureau's ac- curately analyzed standard samples, analysts may check both the

correctness of the methods used by them and their skill as analysts,

and, on the other hand, employers may obtain information on the

character of the work done by their employes. Instructors and stu- dents in educational institutions also need aids of this kind, for otherwise neither can obtain any clear idea of the skill imparted and
54 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

acquired. Certain other samples serve as standards for the preparation of volumetric solutions or as reference standards for checking

calorimetric tests of fuels and other combustible substances. The

first cost of materials is often large and their preparation and analysis or purification involve much additional expense. As stock becomes depleted, it must be renewed.

However conscientiously such materials might be prepared by

private concerns, the public would not place in them the confidence

that is accorded to samples issued by the Bureau of Standards. The

Bureau distributes these samples at approximate cost. During the

past fiscal year 1,629 were called for.

A special appropriation is needed to enable the Bureau to maintain on a permanent and independent basis its series of standard samples of determined composition or high purity. Of such samples the

Bureau now issues 38, and the number will increase greatly in con- sequence of an incessant and enlarging demand.

Determination of Carbon in Steel.

An investigation has been completed and the results published of

the sources of difficulty and error in carrying out the barium car- bonate titration method of determining the carbon content in steel

with means for obviating these. (See Technologic Paper No. 33.)

In addition to the completed work noted above, with reference to

the determination of carbon in steels, many experiments have been

made to ascertain whether or not higher results for carbon are obtained by burning at temperatures much above the ordinary. Many

steels do yield more carbon by a single burning at the high temperature (1,500-1,100° C.) than by a single burning at those commonly

employed (1,000-1,100). The amount is always small, but of moment

when an exact determination is wanted, as with the standard samples

issued by the Bureau. This work has involved the designing and

construction of special furnaces.

Standard Methods for the Analysis of Steel.

A committee of the American Society for Testing Materials has

drafted a report of methods for the analysis of steel to be used in

checking deliveries on specifications. The chairman of that committee submitted the results to the Bureau for criticism and suggestions. Considerable time was devoted to the subject, more with

reference to form and uniformity of statement than to the methods

themselves.

Preparation of Electrolytic Iron.

The preparation of pure electrolytic iron and of alloys of iron and

carbon has been actively prosecuted throughout the year in cooperation with the division of metallurgy. A large amount of iron of sat- isfactory purity and several iron-carbon alloys have been prepared.

Related to one phase of this problem is that of a suitable material in

which to cast ingots for scientific purposes. All commercial articles

tried introduced into the metal some foreign material at the high

temperatures that have to be employed. Thus far magnesia specially

purified has been found most suitable. In order to free it sufficiently

from silica the best commercial magnesite is purified.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 55

Influence of Gases, Oxides, and Slag on the Quality of Steel.

A most important line of research on gases, oxides, and slag in iron

and steel will be taken up as soon as a suitable chemist can be found.

The chemical side of this problem covers methods of analysis, but it is hoped also to make a study of the influence of gases and oxides on

the physical properties of steels containing them in known amounts.

This presupposes exact methods of analysis.

The determination of oxygen in steel by the Ledebur method has

come into special prominence of late in connection with analysis of

ingot iron. The Bureau has been urged more than once to act as umpire in fixing the content of oxygen by the method named. This it has refused to do until enough experience has been acquired to justify

it in certifying to the correctness of results.

Other Investigations with Reference to Iron and Steel.

Other subjects under investigation are: The investigation of the

influence of segregation on the shape and size of the test ingot used

for ladle analysis at steel works; the specification and investigation

of metals to be used by the United States Reclamation Service for

pipes and flumes on irrigation projects in conjunction with engineers

of the Reclamation Service.

Cooperation on Specifications for and Analysis of Nonferrous

Metals and Alloys.

Two conferences within the year have been held at the Bureau

with representatives of important scientific and technical societies

to arrange for cooperation of the Bureau and committees of the

several societies on the subject named above. In pursuance of a

desire to avoid duplication of work by the several societies which

have committees dealing with the same materials, the Institute of

Metals will prepare materials for cooperative test, the American

Society for Testing Materials the specifications, and the American

Chemical Society will study and report methods of analysis. The

Bureau will lend its aid by cooperation with the above societies in

whatever direction it may be needed. A beginning has been made

by taking up methods for the analysis of white metals, on a very

satisfactory sample furnished by the National Lead Co.

International Cooperation on Methods of Analysis for Pig and Cast

Iron.

At the request of the secretary of the American Society for Testing Materials, the Bureau has become represented on a subcommittee

of the International Association for Testing Materials. To this

subcommittee questions of a chemical nature relating to pig and cast

iron are to be referred. The first problem before it is that of coming

to agreement on the methods of sampling and analysis that shall be

used for export shipments. Methods were prepared by the Bureau's

representative and submitted for consideration to the members of the

American committee and approved for the most part. The proposals will be sent to the British and the German representatives

for consideration. The chairman of the American committee of the

international association is very hopeful that these proposals will

lead to a marked improvement in the existing situation as to sampling
56 REPORT OP DIRECTOR OF BUREAU OF STANDARDS.

and analyzing iron that passes from one country to another. It is desired that final agreement shall be reached so that presentation

of the report can be made in 1915 at the next meeting of the International Association for Testing Materials.

Phosphate Rock Analysis and the Determination of Alumina.

A study of the analytical problems in the analysis of phosphate

rock has been much interrupted by other work of pressing importance; nevertheless, progress has been made and one phase of the

problem, i. e., the determination of iron, has been very satisfactorily

elucidated.

Determination of Water in Standard Materials and in Coal.

Work has been done on a method for the determination of minute

amounts of water in organic solids, with special application to some

of the standard materials issued by the Bureau, and the study of

certain methods for the determination of water in -coal.

New Method for the Determination of Rubber.

This method, developed at the Bureau, consists in forming an

insoluble nitrosite of rubber by the action of nitrogen trioxide gas

upon a finely ground, acetone-extracted sample of the rubber sus- pended in chloroform. The nitrosite is filtered out, dissolved in ace- tone, and an aliquot portion of the acetone extract is concentrated

and then distributed over alundum in a porcelain boat, using ethyl

acetate to complete the transfer. After expulsion of all acetone and

ethyl acetate, the residue is burned in a combustion apparatus and

the resultant carbon dioxide absorbed and weighed. From the car- bon found the rubber is calculated upon the assumption that the

nitrosite burned contains all the carbon of the rubber. Details of

the combustion apparatus and operation are given. Results on samples of known composition show the method to be fairly accurate

for raw rubber and high-grade vulcanized products. (See Technologic Paper No. 35.)

The general study of methods of rubber analysis has been con- tinued in cooperation with various committees on rubber analysis

and rubber specifications, and some of the results have appeared in

print.

Iodine Number of Linseed and Petroleum Oils.

The iodine value of an oil is the percentage of iodine which a unit

volume of the oil will absorb. This number indicates the adulteration and may be used to determine the extent of oxidation or thickening. The iodine number has numerous very important incidental

applications.

The factors known to influence the iodine number are the temperature, the time of absorption, the weight of oil taken, and the

excess of iodine present obtained by increasing the amount of iodine

solution. The exact effect of each factor was studied by varying one

at a time.

The iodine values of raw, boiled, and burnt linseed oils, and petroleum oils, were determined by the Hanus method, varying widely the

amounts of oil and iodine used, and the time of absorption. It was
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 5*7

shown that in order to obtain reproducible results, a prescribed procedure must be followed, and conditions stated more definitely.

Lubricating Oils.

In February a conference of lubricating-oil consumers and producers was held at the Bureau to consider questions of common interest, especially the matter of formulating suitable specifications

that can be checked up by physical or chemical test. Nothing positive as to specification resulted from this conference, but several

valuable suggestions were made and the initial steps were taken

toward placing the specification of oil on a scientific basis. An oil

engineer will be appointed during the coming year, one of whose

duties shall be to look into all complaints of poor service of oils

delivered under Governmental contracts in Washington, to ascertain, if possible, the reasons for poor service, whether attributable

to the oil itself, or to its incorrect application, and to suggest remedial measures. It is felt that a close observation of the use of lubricating oil under different service condition in connection with laboratory investigations will, lead to definite specifications and reliable

tests. Chemical Researches on Paper.

A comparison is being made of the methods of determining rosin

sizing in paper, in order to devise an improved method. That used

at present takes no account of nonresinous material soluble in the

extraction mixture. Paper pulps and the changes which occur in

ground wood pulp are being investigated with a view to ascertaining their effect on the quality of paper.

A study has been made in conjunction with the paper section of

two commercial caseins, and particularly the applicability of buttermilk caseins to coated papers. This investigation was made at the

request of the Agricultural Department.

Analysis of Printing Inks.

A procedure of analysis of some of the common printing inks has

been adopted and is given (Technologic Paper No. 39). This is the

result of the experience of the Bureau in the analysis of inks for the

Government Printing Office during the past five years. It is claimed

that the procedure is sufficiently accurate to determine the approximate composition of printing inks.

Hydrogen Electrode Studies.

A study is being made of the changes in acidity (hydrogen ion

concentration) taking place in solutions during the course of precipitations as carried out in chemical analysis. This work is closely re- lated to that mentioned just above, but its application reaches far

beyond the specific case of phosphate rock, since it will result in

placing some of the operations of chemical analysis on a scientific

instead of a purely emperical basis.

Operation and Regulation of Electrotyping Baths.

The Bureau was requested by the Government Printing Office to

remedy unsatisfactory working of their copper electrotyping baths.
58 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

From inquiries instituted at the Printing Office and elsewhere the

need for a systematic study of the best operating conditions and the

control of electrotyping baths became evident. The work done thus

far has been mostly in connection with the copper baths at the Government Printing Office. Nickel baths have also been studied to some

extent. This work will be continued through the coming year. In

the end it will benefit not only the Government Printing Office but

the whole electrotyping industry.

Physicochemical Researches on Organic Solvents.

The Bureau has in progress a number of these investigations such

as the density of anhydrous ethyl alcohol obtained from different

sources; the refractive indices of methyl and ethyl alcohols, their

mixtures with water and each other ; the density and thermal expan

sion of acetic acid and its mixtures with water; similarity of acetone

water and glycerine water.

Other Physicochemical Researches.

Other investigations now in progress are the absolute measure- ment of electrolytic resistance, the mercury-cadmium cell, the critical solution temperature and its use in the determination of moisture.

The latter method has been applied in the determination of the

solubility of water in hydrocarbons—and equilibria in the system

ammonium oxalate—oxalic acid water.

The Determination of Ammonia in Illuminating Gas.

Four common forms of apparatus and a new form designed on the

principle of the dimming wash bottle were tested. The results

show that the amount of ammonia in a gas can be determined with

sufficient accuracy for official or commercial testing with any of the

five forms. Tests were made on different indicators and their suitability for this determination pointed out. The choice of indicator

was found to be of more importance than the form of apparatus

chosen. (See Technologic Paper No. 34.)

Pure Ammonia for Refrigeration Constants.

The Bureau is preparing pure ammonia and other materials used

or susceptible of use (sulphur dioxide, methyl chloride, etc.) in

refrigeration, with a view to the determination of their physical

constants. It is also studying the nature and causes of formation

of a noncondensible gas in ammonia-refrigeration systems.

Study of Gas-Testing Methods.

An investigation is in progress as to the methods for determining

impurities in commercial gas, especially the methods used in municipal or State inspection work, with the object of standardizing

the gas-laboratory practice of this country. A part of this research

has been completed and the results have been published, covering

the determination of total sulphur and of ammonia. Methods of

detecting hydrogen sulphide in gas have been studied to some extent, but the work is not completed. The detection of other impurities has not yet been undertaken.

A more exhaustive study, which will extend over several years,

will cover the methods and apparatus for exact and commercial gas
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 59

analysis. This study will, however, probably be preceded by the

preparation of the constituents of commercial gas in a pure state. The primary object of this preparation is to determine the physical

and chemical properties, especially the heats of combustion of the

several pure gases, but the gases will serve also for making up mixtures of known composition on which to test methods of analysis.

A Simple Gasoline Generator for Sulphur Determination.

The generator is a simple device for saturating a current of air

with gasoline vapor. The mixture of air and vapor burns readily

and the flame which contains practically no sulphur is used to heat

crucibles where the use of an ordinary gas flame might cause the

introduction of sulphur, which is found to a considerable extent in

illuminating gas. It is especially useful in determining the sulphur , content of a substance.

Preparation of Secondary Butter-Color Standards.

In connection with color analysis and color standards the chemistry

division developed several combinations of vaseline, wax, and paraffine which when colored were found suitable for the use of butter

inspectors. It was necessary that the samples have a slightly higher

melting point than butter, that they resemble butter, and that they be

easily tinted to butter color.

Research on the Methods and Standards Employed in Volumetric

Analysis.

Of fundamental importance for exact work in almost all lines of

chemical analysis is a study of the methods and standards employed

in volumertric analysis. A comprehensive scheme for such a research

has been formulated and submitted for criticism and suggestion to

about 150 of the most experienced chemists in this country. From

the replies received it is evident that the need for such a research is

widely felt and its appropriateness as a Bureau problem is admitted,

although opinions differ somewhat as to what phases of the large

problem should be first attacked and also as to the degree of accuracy

that should be striven for.

In view of the above it is hoped that this research can be undertaken in the near future to begin with the study of acidimetry and

the necessarily belated subject of indicators, and be carried out with

a view to the highest practicable accuracy. However, considerable

additional force and equipment will be needed before this important

work can be begun.

Platinum Investigation.

It is felt that the Bureau can do much for scientific and industrial

users of. platinum metals and their alloys with one another. The

information available is meager and manufacturers of such ware are

either unable or unwilling to add to it. The work can be undertaken,

however, only if a reasonably large supply of material is at hand and

ample funds are available for a term of years.

The project involves the preparation of each of the platinum

metals in a pure state, the study of some of their properties as metals

and those of the alloys that result from their combination in varying

proportions.
60 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

It is suggested that the Treasury Department might be willing

to turn over to this Bureau the platinum that is saved in the refining

of bullion. The cutting off of supplies of platinum from Eussia

renders this very desirable. Provision should be made for turning

over of the crude platinum by the Bureau to makers of ware in this

country for conversion into laboratory utensils as needed by the

different laboratories of the Government.

Quality of Chemical Reagents.

The quality of chemical reagents on the market, especially those

of high price and supposedly high purity, leaves much to be desired.

It has become the practice of some of the best known dealers here

and abroad to attach to the bottles carrying reagents a label setting

forth the nature and amounts of the impurities in the reagents, or stating that the impurities named are not in excess of indicated percentages.

The validity of such statements depends on the accuracy and comprehensiveness with which the chemical tests that serve as a basis are made. If the statements are defective, their publication is more

dangerous than the omission of all indication of the degree of purity,

because of the false sense of security given the purchaser.

It has been found at the Bureau, and by many individuals elsewhere, that in very many instances the labels do not state the truth

as to the contaminants mentioned on the labels and also that impurities present are not indicated. The average chemist has not the

time to test his reagents accurately and in detail, even if he knows

what methods to apply. It seems, therefore, that some definite and

radical action should be taken to relieve the situation. A committee

of the American Chemical Society endeavored some years ago, to

take the quality of analytical reagents in hand, but for various

reasons was unable to accomplish anything of consequence. It seems

as if results of value can be secured only by the intervention of some

authoritative institution, like the Bureau of Standards, in whose

statement the chemical public could and would have confidence. Just

what form such intervention should take is not jet clear, but possibly

by controlling at the manufacturing establishments, of the bottling

and sealing of each separate batch of materials, reserving a truly

representative sample for analysis at the Bureau, followed by release

for sale of the sealed bottles after attaching to them the test results.

An alternative plan for very special reagents might be for the Bureau

to purchase material at wholesale prices and to assume all the duties

of bottling and sale, as it does not with most of its standards for

analysis.

Either of these procedures, particularly the latter, would beyond

doubt meet with the hearty approval of chemists everywhere, but

would involve the creation within the chemical division of a special

section, the maintenance of which would involve a considerable ex- penditure for salaries and purchase of materials. This expense

would, however, be covered by the fees charged for inspection and

analysis in the one case and derived from sales in the other.

. A special function of such a section of the chemical division would

be to determine the most accurate methods (with their limitations)

for testing reagents and to give to these methods the widest publicity.
BEPORT OF DIRECTOR OF BUREAU OF STANDARDS. 61

Oxidimetry.

It is suggested that active steps be taken to complete work already

begun upon the uses of permanganate solutions in oxidimentry and

especially with reference to the determination of iron. This work

should be done under the direction of the associate chemists engaged

in the acidimetry problem. If such plan can be actively carried

out, it is believed that substantial progress can be made in the course of a few years. In the interval, up to such time as an adequate force is available, a study of the literature (a large task in

itself), can be made and the details of the work planned. It is thought that the cost of apparatus and materials will not be very

great.

Additional Chemical Assistance.

Attention is directed to the urgent necessity for the immediate

increase of the chemical staff of the Bureau, which is at present

almost entirely engaged upon the chemical work for the Bureau and

the testing of materials for the Government service. The present

force is entirely inadequate for these purposes. In addition the

Bureau should be in a position to undertake more investigations for

the purpose of determining the underlying chemical principles involved in all branches of standardization.

Chemical Tests of Materials.

More than 9,500 chemical tests of materials were made, classified

by character of materials as follows: Irons and steels, 1,016; coated

metals, 392; nonferrous metals and alloys, 670; materials from electrotyping baths, 250; cement materials, 958; asphalt and coal tars,

385; roofing felts, 210; linseed oils, 420; oil driers, 345; paints and

paint materials, 1,022; varnishes, 400; lubricating oils, 127; greases,

14; rubber, 504; rope, 34; paper, 2,138; printing inks, 22; writing

inks, 5; sealing wax, 44; molding wax, 4; flax packing, 46; asbestos,

67 ; roller composition, 7 ; wools, 85 ; soap and soap products, 6

glue, 5 ; miscellaneous, 678.

A point of interest is that the testing done for private parties is, as for last year, only about 1.5 per cent of the total. A total of 1,629

standard analyzed samples have been distributed for standardizing

chemical analytical operations as follows: Samples of irons and

steels, 1,300; samples of brass, 57; samples of ores, 183; samples of

sodium oxalate, 89.

The Bureau's chemical tests were made for about 50 Government

bureaus and establishments, including practically every executive

department, as follows: Agriculture, 4; Commerce, 690; Interior,

44; Navy, 133; Post Office, 65; State, 16; Treasury, 3,864; War,

2,406 ; United States committees and commissions, 258 ; Indian establishment, 2,153; State and municipal institutions, 38; miscellaneous

institutions, 10 ; private parties, 139.

- General Paint Investigation.

Active cooperation with one of the technical societies (American

Society for Testing Materials) has been in progress for several years

to determine the relative value of various types of paint, both for

wooden surfaces and for the protection of iron and steel.
62 BEPORT OF DIRECTOR OE BUREAU OF STANDARDS.

An extensive test of white paints for wooden surface was started

in August, 1912, in the vicinity of Washington. After about two

years' exposure this shows that the single pigments, basic carbonate

white lead, basic sulphate white lead, and zinc oxide are not in such

good condition as a mixture of these pigments, and the indications are that an addition of a certain quantity of extenders, such as barium sulphate, silica, China clay, asbestine, etc., to a mixture of

white lead and white zinc is an advantage;

From tests which have been conducted on steel plates painted

with some 12 standard pigments and exposed to the intermittent

action of water and air, commercial red lead was found to give sat- isfactory protection.

It is intended to confirm these general results by additional tests of those pigments which seem to warrant further investigation.

Analysis of Oil Varnish.

Considerable work has been done on investigation of methods of

analysis of oil varnishes, and while progress has been made the

methods which have yielded promising results are very long and

tedious, and publication has been deferred pending experiments

which it is hoped will yield more rapid and equally accurate results.

Corrosion of Iron and Steel.

Though much study and many tests have been made in an effort

to determine what type of metal is most resistant to corrosion, the

results so far obtained are conflicting, and the user of the material

is at a loss how to specify the most resistant metal.

The bureau is taking an active part in planning an extended series

of service tests in cooperation with a committee of the American

Society for Testing Materials, composed of manufacturers and con- sumers of the types of ferrous metals in commercial use, which it is believed will furnish valuable information. In addition to this

series of tests it is the intention to conduct an independent set of

tests on similar types of metal, entirely under the control of the

bureau, as so many factors enter into this problem that no one set of

results can be considered conclusive.

6. METALLURGY.

The Critical Temperatures A2 and A3 of Pure Iron.

An important scientific investigation of fundamental interest in

defining the properties of iron and steel, completed last fall, is the

determination of the critical temperatures A2 and A3 of pure iron.

The existence and nature of the lower transformation, A2, had been

in dispute for over 25 years, and the interpretation of the properties

of iron in an uncertain condition. With specially designed apparatus

using pure iron from several sources, including samples made at the

Bureau of a purity of 99.98 per cent and freed from gases, A2 was

exactly located at 768° C, and A3 at 909° C. in heating and 898° C.

on cooling. No other critical ranges were found for pure iron below

1,100° C. This investigation called forth the following action by the
REPORT OP DIRECTOR OF BUREAU OE STANDARDS. 63

American Institute of Mining Engineers at the October meeting in

1913:

Recognizing that the work being accomplished by the United States Bureau

of Standards is of great value, not only to the scientific but also to the commercial interests of our country, the persons present at this meeting of the

American Institute of Mining Engineers, held in New York this 17th day of

October, under the auspices of the iron and steel committee of said institute,

most earnestly urge upon the proper National Government committees and

authorities the supreme importance of proper financial and other support to that bureau, and also request that allied and kindred American scientific and

commercial organizations also act in this matter in such ways as in their judgment seem best advised.

The results of this work were also received favorably by the

British Iron and Steel Institute.

Finishing Temperatures of Rails.

A matter of the greatest importance to the public is the production of sound rails. One of the questions involved in their manufacture about which there are differences of expert opinion is the temperature at which rails should be rolled. In order to determine what

is the American practice and to demonstrate the practicability of

accurately gauging temperatures in a steel mill, an investigation has

been carried out on the finishing temperatures and properties of rails.

The Bureau has had the hearty cooperation of four of the principal

rolling mills of the country, their plants being placed at our disposal for this investigation. It was found that the mills roll their

rails at temperatures w

r ell within the specifications, but that the

latter permit finishing temperatures to be higher than those of the

ingots from which the rails are rolled. This specification, which is

supposed to limit rail finishing temperatures to a point slightly above

the "critical range" of steel (about 670° C.), has therefore no significance. There were also determined the expansion coefficients of

Bessemer and open-hearth steels, 0.0000146 and 0.0000156, respectively, per degree C. between and 1,000° C. ; the melting ranges

of rail steels, 1,470 to 1,525° C. ; their critical ranges, below which

it is not safe to roll rails, 650 to 680° C. on cooling; and the distribution of temperature throughout a rail section on cooling front

1,070° O, showing variation of over 80° C. from center to surface.

Melting Points of the Elements.

Among the fundamental constants that enter into many physical

and chemical relations of the elements are their melting points.

There has been completed a determination of the melting points of

the chemical elements of atomic weight 49 to 58, using in part the

method of the micropyrometer which permits accurate measure- ments with samples as minute as 0.001 mg. The following results

were obtained for melting points: Nickel 1,452° O, cobalt 1,478, iron

1,530, manganese 1,260, chromium 1,520, vanadium 1,720, titanium

1,795. In this investigation the Bureau had the cooperation of several chemists both in the United States and abroad who furnished

very pure samples of the elements they had prepared.

Total Radiation from Nickel Oxide.

The application of scientific methods to metallurgical and other

technical processes carried out at high temperatures, necessitates the
64 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

introduction of methods of measuring these temperatures and re- quires, for this purpose oftentimes, a knowledge of the characteristic

radiation or emissivity of heated substances both throughout the

visible spectrum and for the total radiation. Experimental methods

have been devised which are of general application and an investigation completed on the spectral and total radiation of nickel oxide in

the' range 600° C. to 1,300° C. The corrections to p}T rometers using

a single colored light and using total radiation have also been determined when sighted on heated nickel oxide. The monochromatic

emissivity was found to increase linearly with increasing wave

length between 0.5 and 0.7jji and to decrease linearly with increasing

temperature. The total radiation increases with temperature. The

following table gives some of the results obtained

Value of monochromatic emissivity of nickel oxide for

Wave length 0. 5 0. 6 0. In For T=l,060° C. E\= . 88 . 885 . 89

Temperature 800 900 1. 000 1, 100 1. 200 1, 300° C. (Wave length=0. 65^) EX= .96 . 93+ .91 .89 . 87 .85—

Correction to optical pyrometer

(using \=0. 65u) for above temperatures +2 +4 +7 +10 +87 +20

Value of total radiation for:

Temperature °C 600 800 1, 000 1, 200 1, 300

Total radiation (E) 0.54 0.68 0.76 0. S5 0.87

Corrections to add to radiation pyrometer 110 95 75 55 45

Iron-Carbon Equilibrium Diagram.

The fundamental problems in the scientific metallurgy of iron and

steel is the establishment of the " iron-carbon equilibrium diagram " which gives the temperatures at which transformations take place in

iron and steel. This has-been studied by numerous investigators, but

there are still many outstanding discrepancies and uncertainties due

to several reasons,' such as unreliable temperature scales and inaccurate methods of measuring temperatures, impurities both solid and

gaseous in the samples experimented upon, uncorrected factors such

as rates of heating and cooling, etc. An experimental investigation of the iron-carbon system by thermal methods is well under way, making use of the methods and apparatus for determining the critical ranges of pure iron. It is hoped

to finish this work the coming year for the temperature range 0° to

1.100° C. for all possible compositions of the iron-carbon alloys and

using only strictly pure materials.

Besides its purely scientific interest, the interpretation of the ironcarbon diagram affords a basis for the rational heat treatment of

steels, a question of the utmost practical importance.

It is planned to study in detail the exact effect on the iron-carbon

equilibrium of the addition of other elements such as manganese,

silicon, etc., using alloys of exactly controlled composition.

Preparation of Pure Metals and Alloys.

The preparation of strictly pure metals and alloys is absolutely

essential as a basis for providing suitable materials for the scientific

study of the properties of such metals and alloys, and often these very

pure* standard materials are not readily obtainable and sometimes
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 65

not available at all. The Bureau therefore has begun the preparation

of certain pure metals and alloys. The purest iron yet obtained was

prepared at the Bureau by an electrolytic method and then melting

in vacuo ; this iron has been used in the determination of the critical

ranges of pure iron by thermal analysis and by electrical resistance

and as the basal material for making up a very complete series of the

pure iron-carbon alloys. The preparation of irons, steels, nickel and

other pure metals and alloys of the iron group will be continued on

a more extended scale and with the endeavor to product, larger pure

samples than has been hitherto possible, for the purpose of studying

the physical properties of such pure metals and alloys.

Carbon in Steels at High Temperatures.

A more strictly chemical problem, but of very considerable metallurgical interest, is the determination of carbon in steels at high temperatures and the variation with temperature and with other constituents. A preliminary account of such an investigation giving the

accuracy to be expected under certain definite conditions of experiment is in press.

Material for Crucibles.

The most troublesome factor in the preparation of pure irons and

steels is the securing of suitable crucible materials which will not

contaminate the metals during the melting process. A very small

amount of silicon, for example, present in a magnesia crucible will

contaminate iron and its alloys, thus vitiating the purity sought. A

thorough investigation of the methods of preparing inert crucibles

free from such impurities is being carried out and satisfactory small

magnesia crucibles have been made. New methods have been devised and are being tested for purifying magnesia on a scale suitable

for crucibles for the melting of larger samples, and other refractory

materials are also being experimented with.

Physical Properties of Pure Iron.

The study of the physical properties and allotropy of pure iron is being continued by an investigation, about completed, on the electrical resistance and critical ranges of pure iron from 0° to 950° C.

It is shown that there are no anomalies or transformations in iron

below 757° C. (=A2) the temperature at which the electrical resist- ance shows a reversible inflexion, i. e., the same on heating as on cooling. At the upper critical range (A3) there is a transformation

beginning at 894° C. on heating and cooling and extending over

25° C. in each case, acompanied on heating by an actual decrease of

resistance on cooling through A3. A precision of 1 in 1,000,000 was

attained in the measuremnets of the iron resistance, and a new cooling-curve method was used. This work will be extended to the iron

carbon and other iron alloys and it is also planned to investigate the

thermoelectric behavior of iron and its alloys over the same temperature range. This work with that on the thermal behavior, will then

form a rational experimental basis for an adequate theory of the

allotropy of iron and for the explanation of the iron-carbon diagram

as based on the variation in the several physical properties.

65301°—14 5
66 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

Standard Test Specimens.

The American Institute of Metals has been desirous of obtaining

authoritative data on the best forms and methods of preparing standard test specimens of nonferrous alloys and particularly of the

more ordinary bronzes and brasses. The Bureau, with their cooperation, has been carrying out an experimental investigation on standard

test specimens of the zinc bronze: 2 zinc, 10 tin, 88 copper. The

effect on the physical properties of pouring temperatures and

methods of molding and casting have been studied as well as of the

best shape of test pieces and of heat treatment such as annealing and

quenching together with microscopic examination of the structure

of the metal and determination of its transformation temperature.

This investigation is to be extended to other bronzes and brasses as

facilities permit.

Causes of Failure of Railway Material.

The Bureau is charged with the investigation of the causes of

failure of railway material. The prevalence of such failures and

their disastrous consequences need no comment. As a preliminary to

this investigation, with the cooperation of the Department of State

there has been secured considerable information concerning European

regulations and specifications regarding the manufacture and use

of railway material and statistics of railway accidents and failures.

Numerous conferences have been held with representatives of railroads, manufacturers of railway material and representatives of

technical societies responsible for specifications, with a view to planning this investigation to best serve the public, and various manufacturing plants have been visited. These have offered all possible

facilities for aiding in this work.

In addition to the investigation completed on finishing temperatures and properties of rails, a beginning has also been made on an experimental study of what has recently become one of the most

serious and puzzling causes of failure of rails, known as transverse

fissures. The Bureau has been asked for help in this matter by the

Public Service Commission of New York State, has already the

active cooperation of one of the large railway systems, and the offer

of cooperation from one of the rail mills. The Bureau will un- doubtedly be aided by all interested parties. The investigation of

failed rails which have caused accidents and submitted by the Interstate Commerce Commission for examination, has recently been put

on a systematic basis by the addition of special equipment and the

arrangement for a more efficient cooperation of the several divisions

of the Bureau interested.

The various factors entering into the processes of manufacture of

and specifications for rails should be taken up, such, for example, as determining the effects of rolling rails of different kinds hot and cold.

This will require the active cooperation of rail mills and railways.

Through the generosity of Sir Bobert Hadfield, who placed nine

ingots made by various processes including his own at our disposal,

it has been possible to commence a far-reaching study of sound ingots

and rails.

It is planned to make a thorough study of the metallurgical, chemical, and mechanical problems of car wheels including specifications.
REPORT OF DIRECTOR OP BUREAU OF STANDARDS. 67

tests, foundry practice and of the different classes of service on

railways.

Fusible Boiler Plugs.

A fusible boiler plug which had failed to operate, causing a boiler

explosion and loss of life, was submitted for test by the SteamboatInspection Service. The tin plug was found to be converted mostly

into oxide. A systematic investigation of fusible boiler plugs has

been begun including an examination of new plugs for fulfillment of

specifications, and of used plugs to determine their deterioration.

Experiments are also being made on the production of tin oxide from

tin in presence of steam which already indicate that the oxidization of the tin can be greatly accelerated. The durability of fusible

tin plugs would therefore appear to be a serious question. This investigation is of considerable extent, involving the examination of

the properties of several hundred plugs.

Failure of Manganese Bronze.

Another type of failure of nonferrous metals has been brought to

the attention of the Bureau by the board of water supply of the city

of New York, namely, the failures of " manganese bronze " and other

brasses used in the construction of the Catskill aqueduct. These

serious failures appear to be due to faulty methods of manufacture

and the Bureau is beginning an experimental investigation of these

metals in the light of the above experience with a view to determining the procedure necessary to prevent such failures and for the

purpose of developing adequate testing methods to detect faulty

metals of this class.

Thermoelectric Method of Determining the Impurities in Platinum.

In exact chemical combustions in which platinum crucibles are used there is loss of weight of the crucible which limits the accuracy

of these operations. It appeared to the American Chemical Society

highly desirable to make exact measurements of the loss in weight of

various grades of platinum ware on heating and to determine the

composition with least loss. An extended series of such experiments

are being carried out particularly with reference to the effect of

iridium and iron as impurities on loss of weight. A thermoelectric

method of determining the impurities in platinum in terms of iridium

has been developed which permits accurate certification of the platinum content without destroying or even defacing the objects tested.

This method of detecting platinum purity has already been of service

to several Government bureaus, institutions, and firms in the selection of platinum utensils and will probably become of general application. Many persons interested have taken the opportunity

offered by the Bureau to have the purity of their platinum ware

tested here by the thermoelectric method. Some experiments with

crucibles containing rhodium show this metal to be preferable to

crucibles containing iridium or even to pure platinum crucibles.

Nomenclature of Alloys.

Attention has recently been directed to the unsatisfactory status

of the nomenclature of alloys. This question has been taken up by
68 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

the Bureau in connection with committees of the American technical

societies interested and with the International Journal of Metallography. There are prospects of obtaining a very considerable

improvement in a most desired uniformity of usage in the naming of

metallic alloys.

Measurements with the Micropyrometer.

Measurements with the micropyrometer are being carried out on

several problems. This instrument permits the measurement of

temperature of microscopic particles (0.001 mg.) to 3,000° C. and

there is in preparation a series of determinations of the melting

points of some 15 of the refractory chemical elements. Most of

these can be obtained pure only in minute quantities and the method

of the micropyrometer is the only one available for the determination of this important constant for some of these elements. We

have here the cooperation of many chemists who have supplied

samples of pure chemical elements.

It has also been possible to apply the micropyrometer to the

measurement of the monochromatic emissivity of microscopic

samples. This constant has been determined for some 20 elements.

It is expected to determine the melting points and emissivities of all

the available refractory elements and of numerous oxides. The

melting points of several hundred commercial steels are also being

determined by this method.

Method of Sampling Steel.

A matter in which there has been lack of uniformity of practice

in steel works is the method of sampling the method for analysis.

In cooperation with a committee of the American Society for Testing Materials the Bureau has taken the preliminary steps in an

investigation of test ingots including a study of the segregation of

the chemical elements as determined chemically and microscopically

in terms of size and shape of the ingot with the object of determining the best size and shape of the ingot and method of taking the

sample. This work should be followed by an experimental comparison between ingot analyses and those of the finished product, as in

many instances, very embarrassing anomalies have been found. It

is probable that for some products, such as rails, it will be found

advisable to specify the analysis of the finished product rather than

of a sample ladled out of the liquid metal before casting.

Efficiency of Surface Combustion Furnace.

There is also under way an investigation of the efficiency of a sur- face combustion furnace. This is a new type of gas furnace which

gives very high temperatures with less fuel than the usual forms.

Metallurgical Testing.

The following metallurgical tests were completed: There were

submitted 198 samples for test involving heat treatment and thermal

analysis, of which 4 were of nonferrous metals and 194 of iron and

steel; 126 samples were submitted for metallographic testing, of

which 4 involved rail failures, 70 were for identification of metals

or process of manufacture, 13 involved metal failures, and 39

samples were for miscellaneous metallographic testing; and 22
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 09

samples were submitted involving miscellaneous metallurgical

testing.

Of these 346 test items, 201 were for 12 different establishments

of the Government and 45 for the public, or 82 per cent of testing

was for the Government. The Government tests were distributed

among the following: Springfield Armory, Geological Survey, Interstate Commerce Commission, Isthmian Canal Commission, Bureau of Standards, Secretary of Commerce, Bureau of Navigation,

Post Office Department, District of Columbia, Quartermaster Department, Public Printer, and the Steamboat-Inspection Service.

Several of the above tests were of an elaborate nature requiring

extended experimental investigation and some of them required as well thorough bibliographic studies. There has also been heavy

correspondence on specifications for and properties of metals.

Metallurgical Information.

Bequests for information on the metallurgical properties of metals and alloys have come from most varied sources, including Government bureaus, electrical companies, railroads, technical societies,

universities, students, jewelers, inventors, metal manufacturers of

all kinds, patent attorneys, consulting engineers, State governments,

public-service commissions, city governments, automobile manufacturers, etc. From the many letters received on the subject there appears to

be a general demand for United States standard specifications and

definitions of metals and alloys of all kinds, and surprise is sometimes expressed that the Bureau of Standards has not a complete

file of such specifications.

The requests, verbal ana written, for information concerning

properties of metals cover almost every conceivable aspect of the

subject and the information furnished finds its way into many

channels, such as preparation of specifications, improvement of

manufacturing processes, products and instruments, textbooks, detection of fraud or impurities, explanation of failures, patent liti- gation, etc. The following are a few illustrations, many of which

might be given

:

Regarding contamination of nickel by salt for use as to constancy of melting

point of salt in nickel crucibles for thermoelectric calibration.

What is wrought iron?

Metals which expand most and disintegrate least on heating.

Latent heat of fusion of copper, from a technical handbook author.

Several requests as to patinas of different metals, from jewelers and others.

How to prevent corrosion of iron and steel pipes, posts, etc.. from several

Government departments and others.

Definition of bronze and brass, etc. Melting points of many metals, from many classes of people.

Relation of heat treatment to change in dimensions, from manufacturers of

automobile parts.

How to make a copper-titanium alloy.

How to recover lead from used storage batteries, from Navy Department.

How to detect a mechanical, electrical or chemical break in copper wire,

from consulting electrical engineer.

Publications.

In addition to the above questions upon which information was

furnished, the Bureau issued during the year the following metal-
70 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

lurgical publications: " Metallographic testing" (Circular No. 42);

"The critical ranges A2 and A3 of pure iron" (Scientific Paper

No. 213) ; "Melting points of the refractory elements, 1—Elements

of atomic weight 48 to 59 " (Scientific Paper No. 205). The following publications are now in press : " Observations on finishing temperatures and properties of rails," "The determination of carbon

in steel and irons by direct combustion in oxygen at high temperatures," "The emissivity of metals and oxides. I—Nickel oxide in

the range 600 to 1,300."

7. STRUCTURAL, ENGINEERING, AND MISCELLANEOUS MATERIALS.

Structural Steel Column Tests.

An important investigation, now in progress, which is of great

value to the engineering and architectural professions, consists of

series of column tests which the Bureau is now making in cooperation with the steel-column committee of the American Society of

Civil Engineers, and the steel-column committee of the American

Railway Engineering Association.

The series of the American Society of Civil Engineers comprises

nine different types of cross sections. Eighteen columns of each type

are being tested, nine of light and nine of heavier structural shapes.

The nine columns, both of the light and heavy kind, are made in

these different lengths, so that there are three columns of each type

and weight of section having the same length.

The American Railway Engineering Society's columns comprise

18 latticed columns provided with square bearing plates at both ends.

For the present only one type of cross section, but of two different

weights of structural shapes, has been used. Both the light and

heavy columns are made in three different lengths, there being three

columns of each length and weight of cross section.

In addition to these column investigations, a large number of steel

bridge columns have been tested in cooperation with prominent engineers. The columns are facsimiles of members from long-span

bridges which are being erected or soon will be erected in America.

The reports on the data and results of these tests, when completed,

will be very valuable to bridge designers as such data on large sized

columns have not been available heretofore.

The purpose of these tests is to determine the best forms of cross section of columns and also to correct or confirm the formulas used

by engineers and architects for calculating the strength of columns.

Not alone are such formulas valuable for determining the loads

which can safely be carried by the columns used in various structures, but they also enable the designer of columns to make the most

economical use of the steel employed in their construction, i. e., to

make a minimum amount of material carry a given load with safet}^.

The testing of these columns must be done very carefully in order

to secure reliable results. About one-third of the two series of columns have been tested since the beginning of these tests last December. The work has not progressed far enough to admit of drawing

any definite conclusions from the tests, and it may be necessary to

considerably extend the present program of the investigation before

arriving at a final interpretation of the results.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 71

Brick and Concrete Column Tests.

The tests of a series of full-sized concrete columns have been made

on the 10,000,000-pound testing machine at the Pittsburgh branch.

These columns were designed and constructed under the supervision

of a committee of practical engineers in order that they might represent as nearly as possible the actual conditions found in concrete

work. The results of this investigation, as well as that of a similar

investigation as to the strength of brick piers will be of great value

to architects and construction engineers.

Failure of Rails and Railway Material.

At the request of and in cooperation with the division of safety

appliances of the Interstate Commerce Commission, the Bureau has

conducted investigations to determine the causes of rail and tire

failures, all of which caused derailments or wrecks. Similar material is also being collected directly from the railroad companies and

manufacturers of railway equipment. In each case careful chemical,

microscopic and mechanical tests are made to ascertain whether the

metal is of inferior quality, or whether the present day service conditions as to wheel loads are too severe or too great. The results of this

investigation will contribute toward safer railroad communication.

Standard Test Specimen for Cast Bronze.

At the request of the American Institute of Metals, the Bureau has

undertaken the investigations preliminary to the establishment of a standard test specimen for cast bronze. About 800 specimens have

been prepared from a typical bronze consisting of 88 per cent copper,

10 per cent tin, 2 per cent zinc, and tested for ultimate strength. It

is hoped that these results in conjunction with the results of the investigation of the metallurgical division will serve as a guide in the

specification of a standard test specimen for such materials. (See

also Metallurgical investigations.)

Influence of Time in Testing Steel Specimens.

The Bureau is cooperating with the American Society for Testing

Materials in an investigation to determine the effect of the speed of

application of the load on the yield point of a steel specimen in tensile tests. The yield point is the load in pounds per square inch at

which a flow of the metal occurs when subjected to tension or compression. The purpose of this investigation is to ascertain the best

speed of applying the load when making commercial tensile tests of

various kinds of steel. The work has only recently been undertaken

and no analysis of any of the results have yet been made.

Measurement of Strains in Engineering Structures by Means of

the Strain Gauge.

Some time ago the Bureau began an investigation of the measure- ment of strains in engineering structures by means of the strain

gauge. The method was employed on typical bridges, structural

steel buildings, boilers, canal lock gates, and ships, for the purpose of

ascertaining whether or not the method is applicable for the meas- urement of stresses in such structures. Considerable data in connection with these typical cases have been collected, but owing to the
72 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

recent transfer of the expert engaged in this work to the Interstate

Commerce Commission, the publication of the results of this investigation has been delayed.

Wire Cables.

An extensive investigation of causes of failure of wire hoisting

cables has been planned and begun, and steps are being taken toward

the collection of material. This investigation is being carried on at

the Pittsburgh branch, and will cover the various practical uses of

these cables about which very little is known at present.

Calibration of Testing Machines.

It is desirable to test the accuracy of the reading of testing machines from time to time, especially during the course of a long

investigation. With this point in view, the Bureau has secured apparatus for the testing of machines up to 50,000 pounds capacity and

has undertaken the design and construction of an apparatus with

which it hopes to be able to standardize its own machines as well as those of the public to a point which lies as far beyond the 50,000-

pound limit as may be necessary.

Information as to the Strength of Metals and Alloys.

Much assistance has been rendered by the Bureau during the past

year in the form of answers to correspondents seeking information

as to the strength and other properties of metals and alloys. These

inquiries were received from universities, research laboratories, individuals, corporations, and the various branches of the Government

service.

The inquiries covered a wide range of subjects. Many were re- quests for technologic papers and other printed matter; others pertained to standard specifications and standard methods of testing

and some asked for the strength of different articles such as ropes

and knots, chains, wires, riveted joints, brass tubing, etc. The Bureau's opinion has been sought in regard to the accuracy of various

testing apparatus; also in regard to the feasibility of various devices

and structures such as concrete ties and new types of rail. Inquiries

have been made concerning the kinds of testing apparatus needed

for particular purposes and concerning the usefulness of new apparatus. Information as to the cause of failure of manufactured materials has been the basis of many requests.

The information given by the Bureau has been used in selecting

the proper equipment for laboratories, in legal cases, in the testing

of supplies, and in the design of various structures.

Tests on the Strength of Materials.

The tests of compression and tensile strength and transverse bending strength made at the Washington laboratories were for practically all departments of the Government. They included 275 iron

and steel tests; such as reinforcing bars, Army-tent tripod, boiler

plate, button head bolts, boiler flues, twisted type stay bolts, wire

stay bolts, steel anchor bolt, a large number of cast-iron arbitration

bars; 48 tests of copper, and brass and other alloys; 10 cable and

rope tests; and 18 miscellaneous.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 73

In addition, two Biehle testing machines, one of 200,000 pounds

and the other of 400,000 pounds capacity, have been calibrated to

50,000 pounds, at the request of the steel company owning them.

Hydration of Portland Cement.

One of the most interesting investigations completed during the

past year has been one dealing with the hydration of Portland

cement. This study is of prime importance, both to the manufacturer and consumer, since if it were shown that the presence of any

one constituent in Portland cement would give very desirable properties in particular cases, such as quick hardening or slow hardening,

the manufacturer could so control his product that he could obtain

either of the above desired properties. At the same time the con- sumer who might desire either of these, depending upon the conditions, would be able to secure them in the market. Furthermore,

the conditions under which concrete is hardened vary to a great

degree; also the medium in which the concrete is hardened varies

considerably. If, therefore, in a study of hydration, the products

which result under normal conditions were determined, it would be

possible to anticipate what would result under abnormal conditions

of hardening. This present investigation showed what the production of hydration of the constituents of Portland cement are under

normal conditions, and also which of the constituents produced the

early hardening and which the later hardening.

The above investigation was carried on at the Pittsburgh branch

with materials produced in an electric furnace and with some commercial cements, but in no case were the actual products of hydration

compared with the strengths produced. At the present time, however, this investigation is being continued with materials prepared

in sufficient quantity to make specimens for physical testing, and the

results so far obtained on these confirm the results obtained in the

above-mentioned investigation. The burning of Portland cement in

which the various constituents have been carried through wide limits,

has, been continued, as well as an investigation in which the effect

of replacing the lime with magnesia has been studied. In the latter case cement has been burned in which no limestone has been used

in the raw mix, it having been replaced entirely by dolomite. The

results obtained in all the burns have been very interesting, but it has not been thought advisable to publish them until some long time

tests have been completed.

Durability of Concrete in Alkali Waters.

One of the most important investigations started during the year

is being conducted in cooperation with the Eeclamation Service,

the drainage division of the Department of Agriculture, and the

Association of American Portland Cement Manufacturers to determine the durability of concrete of various kinds in concentrated

alkali waters. This is, in fact, an extension of an investigation

started by the Government in 1908, a report of which was published

in Technologic Paper No. 12 of the Bureau. Some 8,000 specially

prepared experimental drain tile were made under the Bureau's

supervision and shipped to badly alkaline districts in Colorado,

Montana, Wyoming, Arizona, Washington, New Mexico, Utah, where
74 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

typical alkalies having different characteristics were found, and to

Missouri, Minnesota, and Iowa, for comparative purposes. These

tile were installed on Government reclamation projects under ex- pert supervision and are to be inspected and tested from year to

year. The results of this investigation will be of much value to the

public and the Government in irrigated districts of the West where

concrete is the most available structural material and will be most

economical for certain purposes if it will resist alkali disintegration.

The people of the West have been somewhat skeptical concerning the

permanency of concrete exposed to alkali waters owing to the failure

of a number of Government and private structures in such districts.

High-Pressure Steam Test of Cement.

The investigation of the value of atmospheric and high-pressure

steam tests as a means of determining the soundness of Portland

cements has been continued. Results indicate that this test can not

be used as a reliable guide. Many cements failing to pass this test are, under normal conditions, found to be sound and equal in cementing value to those which do pass it. This test has been exploited

during the past few years by some engineers and widely discussed

in the technical press. Many requests were received by the Bureau

for information concerning the merits of the test and it was on this

account that the investigation was started. A report giving results

of tests of concretes up to two years of age made with these various

cements will be published during the ensuing year.

Methods of Determining the Time of Setting of Cement.

An investigation was completed which showed the sources of error

in determining the time of setting of cements by the Gillmore and

Vicat needles. This was undertaken because of a controversy

between the engineering societies and the Government as to the relative merits of these apparatus. Neither apparatus was found to be

satisfactory and the Government's contention was supported that

both methods are subject to about the same error and the simpler

should be adopted as standard until a more satisfactory method can

be developed. The determination of the time of setting of cements

is important. If a cement sets too rapidly, it may harden before

it is placed in the forms ; and if it hardens too slowly, it causes added

expense in handling.

Standard Cement Sieves.

The importance of standard cement-testing sieves to the industries

was pertinently brought to the attention of the Bureau by the fact

that one cement mill had to regrind thousands of barrels of cement,

at considerable financial loss, on account of unknown variations in

the standard sieves which they were using to standardize their product. An investigation of " Variations in the results of sieving with

standard cement sieves" was completed during the year and published as Technologic Paper No. 29. A further investigation of the

standard 200-mesh sieves was made and completed, but it has not

yet been published. The results of this investigation suggest the

desirability of changing the specifications for standard sieves and

the necessity of ensuring to the public a standard sample for checking sieves. It shows that the uniformity of sieves should be much
REPORT OF DIRECTOR OP BUREAU OF STANDARDS. 75

improved, as the greatest variation is in the spacing of the warp

wires which are fixed by the accuracy of the reeds, upon which wires

are threaded when the cloth is woven.

Standard Specification for Portland Cement.

Joint meetings with representatives of other Government departments have been held with representatives of the American Society

of Civil Engineers and the American Society for Testing Materials

in an endeavor to obtain one United States standard specification for

Portland cement. These meetings have been productive of suggested improvements to all present specifications and substantial

agreement has been reached on a single specification in all but a few matters, and it is believed all differences will be adjusted before

the end of the ensuing year. The work of this conference made

necessary several investigations of testing methods and has suggested

the inadequacy of present tests and the need of much additional

work of this character. The endeavors of this conference which is

fixing the standard of quality for all American Portland cements

affects the entire industry and assists the engineers by furnishing

them an adequate and practical specification.

Miscellaneous Investigations of Stone, Cement, etc. The miscellaneous investigations have included the investigation

of marbles considered for use in the construction of the Lincoln

Memorial; of floor marbles and composition flooring materials, such

as magnesite, cork, rubber, cement, etc.; of marbles for toilet rooms

to determine their suitability for Government buildings; the cause

of defects and failure of concrete and composition floors in Government buildings ; the suitability of sands for use in concrete ; the cause

of defects in plaster wall; the suitability of certain available materials in reclamation projects for the production of silica cements,

etc. Many of these investigations required several weeks' or months'

work while others were completed within a few days. A total of

538 samples of stone and 138 samples of miscellaneous materials

were tested in connection with these investigations. A very few

tests of cement, concrete, and stones were made for city and State

governments, commercial testing laboratories, cement manufacturers,

stone quarries and the public, mostly in connection with investigations or as check tests. Samples of cement were tested for a cement

manufacturer to determine the relative quality of the product from

his various mills. Samples of concrete were tested for a city which

suspected that a contractor had supplied inferior concrete. Samples

of stone were tested for a State government and for the public to

determine physical qualities.

Investigation of Building Stones.

An advisory committee, composed of representatives from the

United States Geological Survey, Office of Public Roads, Bureau of

Mines, and the Bureau of Standards, was organized to obtain co- operation in a comprehensiA^e field and laboratory investigation of

the stone resources of the United States. In the past each Bureau

has been working in its own particular field and there was no corre- lation in the Avork. Thus, where geologic data were often available

concerning structural stones, the physical qualities were not known
76 REPORT OP DIRECTOR OF BUREAU OP STANDARDS.

or the reverse condition existed. Also, there has been more or less

duplication of work A general agreement as to distribution of

work, in order to avoid any duplication, was reached and a program

outlined. Some new stone working equipment has been purchased

for preparing samples and work will start with the beginning of the

ensuing fiscal year. It is proposed that the Bureau maintain a sample file of the building stones of the United States which will be

available for reference to the Government and public, together with

information on the physical qualities.

Effect of Moisture and Temperature Changes on Concrete.

Work was continued on a study of the volumetric changes which

take place in concrete and the behavior of concrete exposed to various moisture and temperature conditions. Special study has been

made of concrete in street pavements, as the information is necessary

to properly design this type of structure, and prevent subsequent

cracking. The results of this investigation are of interest more particularly to the highway and general construction engineer. There

are so many variables entering into this problem that it will probably

require several years to obtain satisfactory results.

Granular Analysis of Cement.

The development of a granulometric analyzer was completed and

studies have been made of the fineness of about 25 brands of cement.

The results indicate that the quantity of active cementing material in

Portland cements can be more readily determined by an apparatus

of this type than by the use of sieves. A quantitative separator has

also been designed which is capable of selecting the particles of

various sizes and will permit of a study being made of the value of

fine grinding of Portland cements and its effect on quality. The re- sults of this investigation will be of particular value to such Government offices as the Reclamation Service, and is of much general interest to the manufacturer and consumer of cement. If it is found that

only the " flour," which comprises about 35 per cent of the cement,

is appreciably active, considerable saving could be made by separating this material at the point of manufacture and not paying freight

on a very large quantity of relatively inert material.

Durability of Plasters and Stuccos.

An advisory committee, consisting of representatives from the Government, engineering societies, the Lime Manufacturers Association,

Cement Manufacturers Association, Gypsum Industries Association,

and Metal Lath Industries Association, was organized to assist in a comprehensive investigation of the durability of stuccos and plasters. A preliminary investigation was started by the Bureau two

years ago and the present program is an extension of that work.

The work is just inaugurated and no results are yet obtainable. The

investigation was deemed necessary on account of a number of

failures which have occurred in Government buildings, the inquiries

received by the Bureau for information concerning methods of preventing the cracking of stucco, the durability of various kinds of

metal lath, the cause of discoloration of plasters, the proper mixtures to be used, etc., and the general lack of reliable information
REPORT OF DIRECTOR OP BUREAU OF STANDARDS. 77

in this field. This investigation will extend over a number of years

and involves both laboratory and field work.

Effect of Sea Water on Concrete.

The investigation of the effect of sea water on concrete has been

continued by inspecting many concrete structures along the Atlantic

and Pacific coasts of the United States, the coast of Nova Scotia and

New Brunswick, and collating information on the condition of

concrete structures exposed to sea water in various ports of the

world. It is anticipated that during the ensuing year a report will

be prepared showing the conditions under which concrete should be

used in order to have permanency under sea water exposure. The

results of this investigation will be of value to the Government and

all engineers interested in marine construction.

Silica Cements.

The study of sand or silica cements has been continued and a report giving two years' results will be prepared during the ensuing

year. The Reclamation Service are now using this type of cement

on some of their western projects and the investigation was made

with their cooperation. As the cost of silica cements is only about

60 per cent of that of Portland cements, if they are found to have

comparable cementing value, they would greatly reduce the cost of

concrete structures. The cooperation of the War Department was

also obtained in connection with this investigation, as they had used

some silica cements in 1899 and 1900.

Results of Specification Tests of Portland Cement.

A collation of all specification tests of Portland cements made by

the Government laboratories since 1901 is being prepared for publication. Such a report will be of general interest to the manufacturer and consumer of cement giving as it does the chemical

composition and physical qualities of about 90 per cent of the

American brands.

Variation of the Physical Properties of Concrete.

A study of several thousand compression tests is being made of

concrete which was fabricated and exposed in various ways. It will

be shown by this study what precautions are necessary in the fabrication of concrete to ensure a product of known quality. This will

be of interest to all consumers of cement. The Bureau is constantly

receiving inquiries concerning concrete, the elements of which will

be discussed in this paper.

Cement Inspection and Testing.

Cement was inspected during the year at 13 different cement mills

located in Virginia, Maryland, Pennsylvania, New Jersey, New

York, Ohio, Indiana, Kentucky, and Kansas. The inspection work

included the taking of samples, their testing, and the subsequent

inspection of packing and shipping. A total of 7,610 samples were

tested for the Navy and War Departments, Bureau of Lighthouses,

Isthmian Canal Commission, Supervising Architect's Office, District

of Columbia, Lincoln Memorial Commission, etc. Inspection was
78 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

made of 599,400 barrels of cement for shipment to Panama and

148,385 barrels for shipment to Government departments in the

United States, for use in the construction of Federal buildings, river

and harbor improvements, etc. The testing of cement at the Pittsburgh branch has also been for Government bureaus, particularly the

United States Army Engineers. The necessity for this inspecting

and testing of cement is well illustrated by the fact that out of

265,518 barrels sampled, 32,200 barrels have been rejected. In addition 4,200 barrels have been withdrawn by the manufacturer, since

he recognized the inferiority of the material he submitted before

we were readj^ to start our tests. This cement has been submitted by

plants as distant from Pittsburgh as Kentucky and Indiana.

Information Furnished as to Cement and Concrete.

Many inquiries were received during the year from architects, engineers, contractors, and builders who sought information concern- ing methods of waterproofing concrete, the value of waterproofing

compounds, methods of construction to be employed in sea water,

effect of using sea water for mixing concrete to be placed in sea water, physical properties of concretes of various mixtures, the cause

of staining of plaster walls and ceilings, the relative value of various

concrete aggregates, the cause of failure of magnesite composition

floors, methods of preventing the dusting of cement floors, methods

of designing concrete road slabs, suggestions for building code re- quirements, etc. From the general public requests were received for information

on methods of mixing concrete, laying of concrete sidewalks, waterproofing basements, suitability of various materials for use in concrete, design of concrete piles for use in sea water, durability of

composition magnesite floors, the physical properties of stones, the

cause of failure of drain tile, etc. From cement manufacturers, architectural stone manufacturers,

commercial testing laboratories, requests were received for information on the accuracy of sieves, the physical properties of concrete, the

value of fine grinding, the value of silica cements, cause of failure of

drain tile, effect of sewage combined with sea water on concrete, the

value of high pressure steam tests, methods of testing materials, cause of shrinkage of architectural stone, the interpretation of

cement specifications, etc.

Investigation of Paving Blocks.

A study of the toughness of paving blocks which have been taken

from pavements of various ages in 12 cities was made. The method

of construction, wear, and condition were noted, and the resistance

of the blocks of abrasion determined by means of the standard rattler. Blocks of medium toughness and strength were found to give

satisfactory service if put down well, viz, with good concrete foundation, uniform and well-rolled sand bed, and good grouting. The

better the quality of the blocks, the less sensitive the pavement will

be to defects in construction.

Study of White-Ware Glazes.

A study has been carried on of glazes for white ware and vitreous

pottery, free from lead oxide. A well-fused glaze of good appear-
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 79

ance was found but it possesses certain disadvantages which have

been pointed out.

Behavior of Clay in Water Suspension.

The behavior of clay in water suspension under the influence of a

direct current was observed. It was shown that the attraction of

the clay by the positive electrode was a factor in the purification

process only when iron is present in the granular form, viz, as pyrite,

siderite, etc. Clay containing colloidal ferric oxide is not freed from

the latter. The main factor in the elimination of ferruginous impurities is the preliminary process of deflocculation by means of

caustic soda, sodium oxalate, or tannic acid. The electrical con- ductivity of clays with varying water content was studied.

Viscosity of Porcelain at Kiln Temperatures.

The viscosity (tendency to soften) of a series of porcelains at kiln

temperatures was determined. It was found that the viscosity increased rapidly with the kaolin content. The present American porcelains are working with too low a clay substance content. By raising the proportion from 44 to 50 per cent, better standing up qualities are obtained.

Plasticity of Clays.

Three sections of an investigation dealing with the plasticity

of clay have been completed, one dealing with the compression,

tensile and transverse strengths of clays in the dried state, one with

the flow of clay under pressure through an orifice, and one with the

critical study of the method proposed by Atterberg for the estimation

of plasticity. The work upon the plasticity of clays is being con- tinued with special reference to methods of measurement. This

problem is a very difficult one whose solution appears to be in the

accurate study of the mechanical properties of clays in the plastic

state with particular reference to deformation and flow under

pressure.

An extensive research is under way, relating to the effect of dissolves salts upon clay suspensions. This work has special significance, owing to the fact that application is made of these phenomena in the industries, especially the manufacture of sanitary ware

and pottery, in which hand molding is being replaced by the casting

process. The principles underlying the changes brought about by

the addition of small quantities of salts are not of a simple nature.

The work carried out so far shows the injurious influence of clays

carrying soluble sulphates, like the ball clays, and the surprising

effect of air entrapped by the .clay substance. The benefits obtained

by the exhaustion of air from the suspension have been brought out.

Suitability of American Clays for Vitreous Ware.

Several series of investigations are being carried out in connection

with the study of porcelain, having in mind, first, the most feasible

combination of American clays for the production of vitreous din- ner ware; second, the most practicable composition of chemical

porcelain, made entirely if possible from American materials. The

chemical porcelain used in this country has so far been imported

and with the great demand for this kind of product, it seems very
80 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

necessary that the establishment of this industry be encouraged.

Such problems as the determination of translucency are coincident

with the first part of this investigation, dealing with vitreous table ware. The comparison between American and European kaolins

and ball clays is an essential part of this work.

Ceramic Glazes.

Considerable work is being done in connection with ceramic

glazes. The most urgent problems are being selected, such as the

production of a cheap, one fire enamel, to be used in the manufacture

of enameled brick and tile. A collection is being made of glazes and

enamels, for all kinds of products which have proven useful, for

later publication. The study of cast iron enamels, possessing maximum resistance to the action of acids, is contemplated for the coming year. Crystalline glazes of the zinc silicate type are being prepared for microscopic study by the petrographer.

Drying Properties of Clays.

Physical studies are being made of the drying of clays by means

of a specially designed oven in which the critical points during this

process are being observed. The effect of small additions of electrolytes are also being studied in this connection. A study is being

made of the effect of the size of grain upon the drying and the vitrification of shales.

Clay-Shrinkage Disks.

A system of clay-shrinkage disks, which are used largely by pottery

manufacturers for the control of their kilns, has been correlated

with the temperatures to which the shrinkages indicated by the

standard" gauge correspond.

Production of Paving Bricks from Slag.

The work upon the production of paving blocks from fused slag

is being continued. The results previously obtained in small laboratory furnaces are now to be utilized in actually making slag

blocks of practically commercial size by the use of a sufficiently

large furnace.

Strength of Refractory Bodies.

A research is to be begun dealing with the study of the strongest

refractory bodies subjected to compression at temperatures from

1,300° to 1,400° C. Owing to the heavy losses caused in the ceramic

and other industries by the breakage of saggers, glass pots, supports,

etc., this problem is of considerable practical importance. Part of

this work will embrace the comparison of American and European

bond clays for the purpose of eliminating the latter if possible. At

present considerable amounts of these materials are being imported.

Effect of Crystalline Salts upon the Structure of Clay Products.

The effect of crystalline salts upon the structure of clay products

is to be studied in a series of tests. This work was begun during the

past year and it was shown by the destructive effect of such salts as sodium sulphate, sodium thiosulphate, magnesium sulphate, and

sodium chloride that a well-defined limit existed between clay ware
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 81

standing np or failing under this treatment. Clay burnt below 950°

C. failed without exception. It is hoped that a test will be developed

which will tell quickly whether a product will prove durable under

weather conditions or not.

Investigation of Building Tile.

A building-tile investigation is under way. Data collected has

largely been along the line of determination of proper loading for

building inspectors. This is to be followed by tests to determine

bearing power and properties of tile walls, in relation to brick and

other material, fireproofing qualities, etc.

Resisting Power of Earth.

An investigation has been authorized for the determination of

the properties of earths in relation to sustaining power of piles,

foundations, effect of moisture, viscosity effects on time rate of

depression under loads, standardization of soils for the structural

purposes of engineering, etc. This investigation is in cooperation

with the committee of the American Society of Civil Engineers.

Strength of Brick Piers.

A brick-pier investigation has been under way for some time

which will be representative of the bricks manufactured east of

the Mississippi, covering four principal geographical centers of

manufacture. A study is being made of bonds, comparative strength

of mortars, qualities and properties of brick, both individually and

collectively, in piers of various heights. The members are of a size

commensurate with those in practice.

Composition of Window Glass.

An investigation has been started concerning the limits of the

composition of window glass, with reference to the magnesia content, and with reference to the content of alumina. In the literature on glass many contradictory statements are made concerning

these two constituents, and it is hoped that the facts may be brought

out.

Testing of Clay Products.

The testing done by the clay products section for the Government,

especially the Isthmian Canal Commission, consisted of 250 physical

tests. In addition clay testing was done for the United States Geological Survey, covered by the time of one man for three months.

These tests referred to samples of fire clay collected by the Survey

in eastern Pennsylvania and Maryland. Considerable time was spent

in the preparation of a technical report on the white-ware pottery

industry for the Bureau of Foreign and Domestic Commerce. Cooperative tests are also under way for the Geological Survey of

Florida.

A considerable number of tests, approximately 160, were made for

the public, usually free of charge, and comprised preliminary tests of clay as well as special tests and inquiries pertaining to defects and

manufacturing troubles. In addition, 157 tests were made for the

public for which fees were required. The correspondence with manu65301°—14 6
82 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

facturers of ceramic products has been very heavy. In many instances manufacturers have called at the ceramic laboratory with

specimens of the raw materials or finished products. In unusual

cases trips have been made to the plants at the expense of the manufacturers.

Cooperation with Technical Societies.

The Bureau cooperates also with educational institutions and

technical organizations by contributing papers and articles to their

transactions, and taking part in their discussions. Such cooperation

is being carried on with the American Ceramic Society, the American

Society for Testing Materials, the National Brick Manufacturers'

Association, the National Paving Brick Manufacturers' Association,

and a number of State organizations.

Sand Lime Brick.

The action of CO, when introduced into the hardening cylinder

during the manufacture of sand lime brick, has been found to give a product having a compressive strength about 50 per cent higher than

brick produced without the C02

. This should enable the manufacturers of sand lime brick to improve the quality of their product,

with little extra expense, and should therefore be advantageous to

the users of brick, or the general public.

Strength of Lime Mortars.

Measurements of the various strengths of lime mortars show, first,

that these strengths are generally low, and second, that laboratory

measurements are not reliable. These results are negative only,

but should prove of interest to architects and engineers. The shearing strength of a lime mortar is somewhat less than its compressive

strength. The area in shear should be about one and one-half times

the area in compression, in order to measure the shearing strength.

Properties of Lime.

A method has been developed by means of which it is possible to

tell beforehand whether or not a lime plaster will " pop " or " pit

on the wall; that is, whether small particles will fall out and leave

pin holes. This test should be valuable to lime manufacturers, plasterers, and owners, by eliminating, or at least fixing the responsibility for, " popping."

It has been found that hydrated lime spoils by air-slaking quite

rapidly when stored in the ordinary commercial packages. This

fact is of especial interest to the dealer and the small user. The quantity of sulphur in a lime bears a certain general ratio

to the amount originally present in the stone plus that in the fuel

used to burn the lime. This is of importance to the lime manufacturer because the presence of sulphur is frequently the cause of

inferior quality of the lime.

The amount of carbon dioxide in a lime (which is indicative of

the amount of air-slaking) can be determined rapidly and with fair

accuracy by titration, using phenacetolin as an indicator. This

method is not scientific, but can be used for plant control by the

manufacturer, or for inspection by the user.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 83

Effect of Temperature During the Hydration of Lime.

When lime is slaked there is a tendency toward local overheating

of the material with the production of " lime which has been burned

during hydration." It is believed that the presence of this material

is the cause of popping, and also of the lack of plasticity in some

commercial hydrates. An attempt is being made to find out what

this material is, how it is formed, how its formation can be prevented, or how the effects of it can be nullified. Its isolation has not

been accomplished as yet. The material is believed to be formed

whenever the temperature in any part of the mass of lime and water

is permitted to exceed 350° C.

Plasticity of Lime.

Whenever lime is used for masonry or plastering purposes its use depends primarily on its plasticity, or working quality. This property must therefore be included in any rational specification for lime.

The development of a test for plasticity has been carried out along

lines suggested in Merriman's " Mechanics of Materials," and the

test is now being applied to commercial hydrates of known working

qualities, in order to determine its value. It is believed that the

plasticity of hydrated lime depends to some extent on the size of

grain of the material. Commercial hydrates have been separated

into grains of different size by elutriation (water notation), but this

question can not be finally answered until the method of measuring

plasticity is fully developed.

Use of Lime in Portland Cement Mortar.

It has been found that as much as 25 per cent hydrated lime can

be used in a Portland cement mortar without material diminution of

strength, whether the lime is magnesian or high calcium, and whether

the mortar is permitted to set in the air or under water. These

conclusions are based on tests of specimens 1 year old. Specimens

have been made up to be tested when 2 and 5 years old.

Properties of Gypsum.

An investigation is being made of the physical, chemical, and

optical properties of gypsum, which has been calcined at different

temperatures, in an attempt to throw some light on the behavior of

some of these products which at present appear inexplicable.

Lime Testing.

The commercial testing of lime done by the Bureau has been very

limited, and is confined almost exclusively to locating the cause of

an inferior quality of product, at the request of manufacturers.

Information as to Lime and Its Products.

Requests for information come mainly from present manufacturers in regard to quality of product; prospective manufacturers,

in regard to plant equipment ; and users who wish to know the location of the nearest producer and the quality of his product. Under

users is included a large number of inquiries about the properties of

sand lime brick. The National Lime Manufacturers Association and
84 REPORT OF DIRECTOR OP BUREAU OF STANDARDS.

the American Society for Testing Materials have committees which

are attempting to write specifications for lime. The Bureau is co- operating with both of these committees.

Textile Investigations.

Owing to the large amount of textile testing done for the Government in connection with the purchase of textiles, and the adoption of

the new tariff schedule, it has been impossible to take up any new

investigational work, some of which is very badly needed in connection with the improvement of the methods of testing textiles and

their specification. A few of the most urgent are as follows: (1)

The moisture content of cotton, wool, silk, and linen yarns and

fabrics at various atmospheric conditions. (2) The correctness of

worsted yarn numbers, the percentage of oil present, and the tensile

strength of those sizes of yarns having a large consumption. Many

mills have furnished yarns for this investigation but we have been

unable to proceed with this work. (3) The effect of twist upon the

tensile strength of cotton, wool, and linen yarns and the amount of

twist that will give the maximum tensile strength. (4) The cotton

spool-thread investigation. (5) The development of better methods

of testing and cooperating with the textile trade relative to adopting

standard methods for tests. (6) The quantity of sizing and loading

material in cotton cloth and its effect upon the strength of the fabric.

Strength of various sizes of yarns should be a valuable one for our yarn manufacturers, buyers, sellers, and the textile trade in general.

(7) The effect of humidity upon cotton and wool cloth relative to

weight and tensile strength. (8) Investigation of adulterated textile articles now upon the market. There is complaint by consumers

everywhere that textiles are misbranded and misrepresented by the

mills producing them, by the middlemen and by those selling them

over the counter in stores. Shrinkage of Wools.

By shrinkage is meant the total loss of weight in raw wool, due to

the removal of all grease, dirt, or other foreign matter. This information is needed by wool growers, manufacturers, commission merchants, and especially by those interested in the question of placing

the testing and sampling of wool on a more scientific basis.

. This investigation was made (1) to obtain some definite knowledge

as to the shrinkage of some of the foreign raw wools imported into

this country, (2) to ascertain the shrinkage variation in two samplings of the same fleece, and (3) the difference in shrinkage between

two fleeces of the same breed of sheep. There were 49 fleeces experimented upon, and the shrinkages ranged from 19.5 to 54 per cent, i. e., the yield of clean wool was from 80.5 to 46 per cent, according to

the breed of the sheep. In the South Australian wools the greatest

shrinkage difference between two determinations upon the samples

drawn in the same manner from the same fleece was 3 per cent, while

for the New Zealand wools the largest difference was 6 per cent. The

differences were calculated on the basis of raw wool weight. The

difference in shrinkage between two fleeces of the same breed of

sheep grown in the same location was found to be as great as 9.5 per

cent.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 85

Information as to Textiles.

The Bureau is assisting the Department of Agriculture in determining the maximum temperature Egyptian cotton fiber can be

heated without causing deterioration to its strength. This information is desired in connection with an extended investigation by that

Department of the injurious effect of the pink boll worm (an insect

very injurious to cotton fiber) found in imported Egyptian cotton.

The Bureau has published for distribution Technologic Paper

No. 19, on "The physical properties of cotton yarns," also Circular

No. 41, which gives a general outline of textile analyses performed

by the Bureau, drawing attention to particular conditions and

methods of test that should be followed, precautions to be exercised,

rates of charges, etc. This circular has served in a very large way

to educate the textile trade along the lines of more scientific buying

and selling of textiles.

During the year the Bureau tested over 2,400 samples of textiles,

mostly of materials purchased by the Government. These included

cotton, silk, and linen cloths, spool thread, tracing cloth, areoplane

cloth, automobile-tire fabric, sail cloth, canvas, tent cloth, table linens,

artificial silks, wool cloth adulterated with cotton, cordage, etc. The Bureau was called upon as referee in a controversy between

a cotton mill and a consumer of large quantities of automobile-tire

fabric. Tests were made upon samples of fabric.

The textile section of the Bureau has assisted in the drafting of

textile specifications, particularly for Government purchases, and to

some extent for the public. It has rendered valuable assistance in

court cases, and assisted various committees. The Bureau cooperated

with the Bureau of Foreign and Domestic Commerce in the testing

of domestic and foreign-made jute bagging for cotton. This work

was of considerable value and the results were published by that

Bureau in a pamphlet entitled "Cotton bagging and ties," October

20, 1913.

A special report was made to the Ways and Means Committee,

House of Representatives, relative to methods of testing cotton cloth

for duty assessments under the new tariff law.

The Customs Service at the Appraisers Stores, New York, were

furnished a short and accurate method of determining the yarn

number upon imported cotton, wool, silk, and linen yarns.

A complete revision of the textile specifications of the material purchased on the " General supply schedule " was furnished to that committee. The Bureau drafted specifications for the purchase of textiles

required by the Office of Indian Affairs, Department of the Interior.

In the case of both offices mentioned above the textile section tested

the bidder's samples and assisted in the making of all awards for contracts for the fiscal year ending June 30, 1915.

At the request of the Treasury Department, a representative of

this Bureau visited the New York Appraiser's Stores, made a report

of the textile work there, and suggested more efficient methods of

appraising importations.

The War and Navy Departments were assisted in their textile

specifications and in the matter of testing various materials under

dispute.
86 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

Several bills before Congress relating to the enactment of a " purefabric law" were submitted to the Bureau for criticisms and suggestions.

Paper Investigations.

A study of the causes of deterioration of paper for permanent

records has been undertaken and will be advanced as fast as possible.

The results of such a study will be of utmost importance to the general public.

The question of the influence of atmospheric moisture on paper

during the process of color printing has been suggested by lithographers and printers as a problem of great importance to the printing industry. Work along this line has been started.

The investigation on butermilk caseins and its application to the

paper industry for sizing and coating paper, is well under way. The

results obtained so far indicate that buttermilk caseins will have

almost as large a field of usefulness as skim-milk caseins. To facilitate this investigation the Bureau has installed a complete machine

for coating paper. Cooperative work with mills making coated paper

is in progress, and one mill has given assurance that it will assist the

Bureau to make the final determinations on a commercial scale. This

mill has already given much valuable assistance. The final results

of this investigation will be of value to the dairy, paper, paste, and

other industries using casein. Buttermilk, now a waste product, may

be turned into a new source of supply for usable casein, and at the

same time lower the cost of casein to the industries.

The past year's work of the paper laboratory has clearly demonstrated that imr estigation work has been seriously handicapped, due

to the large amount of routine work required by the departments and

the small laboratory force available for this work.

Paper Conference.

The second annual conference between paper manufacturers, commercial testing laboratories, and this Bureau was held at the Bureau

of Standards. This conference has resulted in establishing a closer

spirit of interest and cooperation between the parties concerned and

has enabled this Bureau to present the Government paper requirements to the manufacturers. These conferences will be held annually

and for the purpose of affording an opportunity for discussions

along technical lines relating to the paper industry. This annual

yearly conference will result advantageously to the entire paper industry, as well as the public.

Paper Testing.

During the past year the Bureau has tested the following samples

of paper : For all Government departments, 2,749 samples; for public

and private interests, 242 samples; total number of samples tested,

2,991. These tests were made for practically all departments of the

Government, the Government Printing Office, and other establishments. This large amount of routine work has made it almost impossible to give much attention to those investigations which have

been undertaken.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 87

Information as to Paper.

In addition to the routine testing of paper purchased by the

executive departments, they have been given every possible assistance

both in the preparing of paper specifications and in securing papers

best suited to their particular needs. Such assistance has enabled the

Government to substitute lower priced paper for the higher grades,

and in a few instances it has been pointed out that a higher grade

ought to be used. The question of chart paper for the United States

Coast and Geodetic Survey has received considerable attention, and

it is believed that the investigations along this line will result in

securing a chart paper of higher quality.

The circular on paper and paper testing is nearly completed. It

will enable the small user to more correctly judge a paper for a particular use. Suggestions have been received from a number of paper companies

that this Bureau take up the standardization of paper and paper

testing not only as applied to Government purchases, but also as applied to the entire paper industry. Such standardization would

be of great importance and benefit to both manufacturers and con- sumers of paper. This work should be undertaken by the Bureau.

Hack-Saw Blades.

An investigation to determine the relative efficiency of different

makes of hack-saw blades has been in progress for more than a year.

This work was undertaken at the request of the Government and a committee of manufacturers of hack-saw blades. The results thus

far obtained indicate that the specifications in general use are inadequate to determine the wearing quality of blades. The work, which

has been subjected to numerous interruptions, will be pushed as rapidly as possible with the view of developing reliable tests and

specifications.

Properties of Rubber.

A study of the physical properties of rubber, with special attention to the influence of temperature on these properties, has been

continued during the past year. In conducting this work practically

all of the apparatus and testing machines have been designed and

constructed at the Bureau. The results of many tests that have been

made, both on routine samples and on samples secured for experimental work, will be used in revising Circular No. 38, which illustrates and describes the apparatus and methods employed in testing

rubber at the Bureau. This circular is now in its second edition and

the demand for it is steadily increasing.

An experimental rubber mixing and vulcanizing plant has been

installed, and is now ready for operation. This plant will be of

great value to the Bureau in preparing samples of definite composition which will be used for experimental work both in the physical

and chemical laboratories. The Bureau has already rendered valuable assistance both to manufacturers and consumers in improving

existing methods of testing and in designing special apparatus to

expedite and facilitate the various tests.
88 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

In addition to the many tests of rubber made for Government departments, the Bureau has cooperated with technical societies and

with manufacturers in developing specifications and methods of test- ing. Numerous requests have been received for working drawings

of the testing machines that have been developed at the Bureau, and

in every case the desired information has been supplied. A number

of these machines have been adopted by the leading rubber manufacturers of the country and by some of the largest testing laboratories engaged in the testing of mechanical rubber goods.

Tests of Miscellaneous Materials.

A total of 1,347 samples of miscellaneous materials, principally

for Government departments, were tested during the year. These

included 200 samples of rubber hose, 644 samples of packing (rubber

asbestos, etc.), 45 samples of rubber bands, 69 samples of rubber

covered wire, 135 samples of asbestos gaskets, 41 samples of leather

belting, 71 samples of rope, 28 samples of hacksaw blades, and

others.

8. ENGINEERING RESEARCH AND TESTING.

Applications of the Dimensional Method to Physical Problems.

An investigation of the dimensional method of attacking physical

problems is under way. The " Principle of dynamical similarity,"

necessary in the interpretation of experiments on mechanical models

(ships, aeroplanes, etc.) is the most familiar instance of the application of this method; but the importance of the method is much

greater, especially in technical physics, and its applicability far

wider than has commonly been recognized. A general and fully

illustrated exposition of the subject is in preparation, several preliminary papers dealing with special chapters having already been

published in scientific and technical journals.

Windage Resistance of Steam Turbines.

A general equation was deduced from the theory of dimensions,

which is shown to agree with such experimental data on windage as have been published. The data at present available are not adequate as a basis for the computation of windage corrections, except

in a few simple cases. (See Scientific Paper No. 208.) The data

are analyzed and suggestions offered as to practical computations.

By applying the principle of dynamical similarity, it is shown that

model experiments may be utilized and the practicability of such

experiments is discussed.

The problem is an important one in turbine design and operation.

Water-Current Meters.

During the past year 266 calibrations of current meters, used for

the measurement of the velocity of flow of water in streams, open

channels and ocean currents, were made by the Bureau for the

United States Geological Survey, Beclamation Service, and other

Government departments, State governments, and engineers in

private practice.

The number of instruments submitted for test showed an increase

of 33 per cent over the previous year.
REPORT OF DIRECTOR OP BUREAU OF STANDARDS. 89

To provide better conditions for the routine rating of these important instruments and facilities for a comprehensive investigation

of the characteristics of the different types, a concrete tank 400 feet

in length has been constructed and special apparatus for automatically recording data has been designed. The new station will be

in operation early in the next fiscal year.

Anemometers.

Within the last year or two there have been frequent requests

for information relative to the use of anemometers of the vane type

for the measurement of air velocities encountered in fan, ventilating,

and similar work. These instruments are distinct from those used

for meteorological measurements. Requests have been made for

tests as high as 10,000 feet per minute. The Bureau is unable to

make these tests or supply the information requested. An investigation to determine what instruments are suitable for this service,

their characteristics, and the best method of calibration, would furnish data which is greatly needed by engineers in this field.

Gasoline Engines.

The Bureau has installed a gasoline-engine testing plant for determining the power and fuel consumption, at various speeds, of

motors such as are used in automobiles, motor boats, and aeroplanes.

Preliminary tests were made on two Renault aeroplane motors for

the United States Signal Corps.

This apparatus was installed by and is to be used in cooperation

with the Signal Corps, in order to furnish reliable means for testing

such motors as +hey might acquire or contemplate purchasing.

Vacuum Traps.

A request was received from the Supervising Architect of the

Treasury Department for data to be used in the preparation of

specifications for purchase of vacuum traps used in the steam-heating

systems of Government buildings. Special apparatus has been constructed for this purpose, and an investigation of the operation under

working conditions of some 18 different makes of traps is now in

progress.

Hose Couplings.

The great benefits that would result from a standardization of fire- hose couplings has long been recognized, and lack of uniformity in

this respect has been responsible for great loss of life and property

in certain large conflagrations, such as the Baltimore fire in 1904,

when fire engines sent from other cities in response to calls for aid

were unable to render assistance for the reason that their hose

couplings, being of different design, would not couple up with the

local fire-hose connections.

This Bureau has for a number of years been in cooperation with

leading fire-protection organizations of the country with the view of

establishing a standard fire-hose coupling. As a result of this co- operation, a large number of cities and the leading fire-protection

associations have adopted a standard design known as the national

standard fire-hose coupling. In order to render this important move-
90 REPORT OF DIRECTOR OF BUREAU OF STANDAKDb.

ment as far-reaching as possible, the Bureau of Standards has prepared a circular outlining the history of the undertaking and setting

forth the advantages to be derived from the general adoption of the

standard coupling.

Miscellaneous Instruments and Devices.

As a result of tests completed by this Bureau during the past

year for the Treasury Department, portable vacuum cleaners supplied to that department for use in public buildings under its control are now purchased under specifications, by the provisions of which

the efficiency and effectiveness in operation of these machines may be

determined and compared by simple tests. In addition to the rating of current meters, 145 tests of other

instruments were made, including steam, vacuum and hydraulic

gauge's, water meters, fire extinguishers, valves, vacuum cleaners,

dynamometers, paper tester, and miscellaneous devices.

Facilities Needed for Engineering Research.

The large and steadily increasing demands made upon the Bureau

for routine tests of this nature render it impossible, with the present

working force, to make satisfactory progress in the several lines of

investigation that have been undertaken. There are many important

engineering researches that should be undertaken and perhaps no

greater assistance could be given both the Government service and

the manufacturing interests of the country than by the development

of adequate facilities for such researches. The Bureau's work in

this field has scarcely begun and is limited almost exclusively to a few of the more pressing cases of the Government service.

m. OFFICE, AND ENGINEERING AND CONSTRUCTION.

1. OFFICE.

Publications.

During the past year the Bureau issued four numbers of the

Bulletin of the Bureau of Standards, completing the tenth volume

of the bulletin; 23 scientific papers; 11 technologic papers; 5 circulars; and 2 miscellaneous publications, a total for the year of 41

Bureau publications.

The following new circulars were issued during the year : " Metallographic testing," " The metric carat," " Polarimetry," " The testing

of materials," and " The testing of barometers."

The following scientific papers were issued : " New calorimetric

resistance thermometers," " The silver voltameter—Part III, second

series of quantitative experiments and the preparation and testing

of silver nitrate," " Note on cold-junction corrections for thermocouples," " The analysis of alternating-current waves by the method

of Fourier, with special reference to methods of facilitating the computations," "The constants of spectral radiation of a uniformly

heated inclosure, or so-called black body, I," " Melting points of the

refractory elements; I, Elements of atomic weight from 48 to 59,"

"High-frequency ammeters," "A comparative study of American

direct-current watthour meters," "Windage resistance of steam-turbine wheels," " Latent heat of fusion of ice," " Observations on ocean
. REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 91

temperatures in the vicinity of icebergs and in other parts of the

ocean," "Accuracy of the formulas for the ratio, regulation, and

phase angle of transformers," " Melting points of some refractory

oxides," "Critical ranges A2 and A3 of pure iron," "Note on the

setting of a mercury surface to a required height," " Micrometer

microscopes," " The pentane lamp as a working standard," " Testing

potential transformers," " Comparison of the silver and iodine voltameters and the determination of the faraday," " Production of temperature uniformity in an electric furnace," " The silver voltameter

Part IV, third series of quantitative experiments and special investigations," and " Flame standards in photometry."

The following technologic papers were issued : " Surface insulation

of pipes," " Electrolysis in concrete," " Electrolytic corrosion of iron

in soils," " Special studies in electrolysis mitigation, I, a preliminary

study of conditions in Springfield, Ohio, with recommendations for

mitigation and control," "Variations in results of sieving with

standard cement sieves," " The viscosity of porcelain bodies," " Some

leadless borosilicate glazes maturing at about 1,100° C.," " Special

studies in electrolysis mitigation, No. 2, electrolysis from electric

railway currents and its prevention—an experimental test on a system

of insulated negative feeders in St. Louis," " Determination of car- bon in steel and iron by the barium carbonate titration method,"

" Determination of ammonia in illuminating gas," and " Combustion

method for the direct determination of rubber."

The following miscellaneous publications were issued : "Annual

report of the Director for the fiscal year ended June 30, 1913," and

"Eighth annual conference on the weights and measures of the

United States."

In this connection it should be stated that the length of time

required to print the scientific and technical papers of the Bureau

often necessitates preliminary announcements through the technical

press instead of by Government piiblication. This is to be regretted,

and it is hoped that more prompt methods may be found to eliminate all possible causes of delay. The decrease in the Department's

allotment for printing may hamper the Bureau in new publication

and keeping in stock publications required in the ordinary conduct

of its business.

Delays occur in the present indirect method of forwarding franks

to the Superintendent of Documents. As the Bureau is located at a distance from the city, the franks addressed at the Bureau should

be sent by messenger direct to the Printing Office. The documents,

it is believed, could then be mailed the same day when necessary, or

in emergencies the messenger could assist in inclosing them. At

present, the Bureau can not remedy the delay which in many cases

is a week or more. The urgent reason for a more direct system is

that in many cases the publications should really be sent as inclosures

in letters, since they are intended as a part of the reply giving information desired.

Library.

The Bureau maintains a working library of reference and cur- rent periodicals on subjects directly connected with the Bureau's

work. It contains nearly 12,000 volumes related to its work. Those
92 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

engaged in research and investigation work must have available the

reference works required for consultation without overcrowding the

library with books which may be borrowed from other scientific

libraries of the city. The cooperation of such libraries in the loan

of books, developed during the past few years, has proved to be of

great assistance in scientific work.

Correspondence.

A large amount of technical correspondence in addition to the

necessary routine connected with tests and the business administration of the Bureau requires a competent force of clerks. In the

file rooms approximately 55,000 letters were handled during the

year. The files are by subject and are indexed by card catalogue. The

vertical files of the unit system have been in use since the Bureau

was established and have been found very convenient. The increase

of about 40 per cent in the amount of correspondence over the

previous year has taxed the force required to handle it. Assistance

will be required to do the work efficiently.

Storeroom.

In the storeroom is centralized the purchase of standard stock and

supplies and the care and record of property. The property record

is maintained as a card catalogue, classified by serial number assigned

when equipment is received, at the Bureau. A duplicate card is

classified according to the nature of the equipment. A record is

also maintained classified by divisions to which the equipment is

assigned. The inventory property of the Bureau now includes, approximately, 50,000 items, a large portion of which includes scientific

apparatus. With the growth of the equipment and the increasing

work connected with property records, it is necessary that a highgrade clerk be provided to serve as a property clerk for this equipment.

Personnel.

During the year the Bureau staff comprised 230 statutory appointees, and about 107 engaged in researches and investigations

specially authorized by Congress. The statutory positions included

144 scientific positions, 29 office assistants, 33 engaged in the operation of the plant, and 23 in the construction. There were 446 personnel changes during the year. These included 105 separations

from the Bureau, of which 38 were resignations. In the consideration of civil-service certificates, it may be of interest to note that 62

eligibles declined appointment, 11 of whom declined after acceptance

and appointment.

The work of appointments is greatly embarrassed by the difficult}^

of securing suitable eligibles for many of the places, also by the

delay usually from one to three weeks in receiving certificates after

making request.

The routine connected with personnel actions is also involved, new

appointments, for example, requiring about 30 distinct steps in the

ordinary course.

Appropriations and Accounts.

With the responsibility resting on the Bureau to audit accounts

prior to payment, the labor of examining accounts has increased.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 93

The volume of Bureau accounting has increased threefold during the

past few years. A much closer accounting system has been adopted,

which permits systematic summaries showing the itemized detail for

each class of expenditure and for each appropriation by administration divisions of the Bureau. The system and form of statement were

developed at the Bureau and is believed to be in many respects the

simplest and most complete statement of Bureau expenditures which

has ever been in use. The design and installation of dispatch boards

covering the various branches of the work of the office has distinctly

aided the Bureau in keeping track of its routine work. While it can not prevent delays due to lack of assistance, the system has made

it possible to keep the closest track of outstanding work and schedule

business.

Attached hereto are tables showing the amount and object of each

outstanding appropriation, together with the disbursement and bal- ances up to June 30, 1914. The first statements cover the appropriations for the fiscal year ended on that date. The second table covers the outstanding disbursement and adjustments on account of the

appropriations for the fiscal year 1912 and 1913, respectively.

The following statement shows the amount and object of each

appropriation provided for the Bureau for the fiscal year 1914, the

v 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, 1914

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

S290, 940. 00 $258,528. 85 811, 595. 03 $20, 816. 12

60, 075. 00 56, 132. 40 3,854. 49 88. 11 General expenses 25,200.00 19, 357. 52 4,788. 13 1, 054. 35

3,000. 00 2, 888. 27 111. 73 Testing structural materials 75,000. 00 69,961.65 4,991.35 47.00

30, 000. 00 24, 204. 20 5, 777. 23 18. 57 High potential 15, 000. 00 13, 757. 64 1,214. 85 27.51 Refrigeration constants 15, 000. 00 11,434. 63 3,552.99 12.38

25, 000. 00 18,573.23 6,389. 92 36.85

Fire-resisting properties 25, 000. 00 9, 404. 45 15,047.73 547. 82 Warehouse and storehouse 45,000.00 18, 623. 39 24,226.99 2,149.62 Tank 5,000.00 4,964. 05 31. 50 4.45 Equipment, electrical laboratory 25,000.00 24,942.38 50. 43 7.19

200,000. 00 197,356. 50 1,594.44 1,049. 06

Total '. • 839, 215. 00 730, 129. 16 83,226.81 25,859. 03

The following statement shows the condition of the appropriations

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

1914:

Appropriation.

1912

Total appropriation. Disburse- ment. Liability. Balance.

$236,340. 00

52,027.50

25,702. 77 3,000.00

78, 533. 50

30,000. 00 15,000.00

$224,050. 96

50,586.89

25,320.03 2,892.93 77,988.62

29, 793. 92

14,877.31

$12,289.04

251. 67

335. 39

107. 07 296.20

206.08

119. 04

Equipment $1,188. 94

47.35 Grounds

Testing structural materials 248. 62

Investigating effects of electric currents

Total

3.65

440,603. 77 425,510.66 1,488. 56 13,604.55
94 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

Appropriation.

1913

Total appropriation. Disburse- ment. Liability. Balance.

$241.312. 66 51,000.00

23,200. 00 3,000.00

77,342.50 30,000.00

10,000.00 15,000.00

$226,682.95

49, 462. 50

22, 701. 09 2,986.81 77,045.29

29,839.03 9,919.63 14,597.86

$14,629.71 381.05

316. 01

13. 19 249.22

158. 87

72. 87

12.04

Equipment $1,156.45

182. 90

rjrnn r\f\ ^ Testing structural materials Testing machines

Investigating effects of electric currents

Refrigeration constants

Total

47. 99

2. 10 7.50

390. 10

450,855.16 433,235. 16 1,787.04 15,832. 96

Summary of Tests and Fees.

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

amount of testing of standards, measuring instruments, and materials. Much of it involves investigation of the scientific principles

underlying the test, a study of existing methods, and the development of new standard tests of known accuracy. For the test a rea- sonable fee is charged, except when made for the National or State

Governments.

During the fiscal year 1914 the Bureau made 107,741 tests and

inspected 1,078,127 incandescent lamps at various factories for other

departments of the Government. Of the total tests 96,687 were for

the Government, and 11,054 for the public. The testing was distributed as follows, according to nature of tests: Length measures,

612; mass, 61,176; capacity, 4,000; temperature, 11,010; hydrometry,

1,207; miscellaneous, 74; optical, 1,475; electrical, 724; photometry,

1,883; chemical, 10,543; engineering (miscellaneous), 1,440; engineering (instruments), 277; structural materials, 8,706; paper and

textiles, 4,614. The estimated fees amount to $127,413, of which

$12,989 were collected on account of tests for the public. The fees

noted for Government tests are included merely for comparison purposes, as no charge is made for tests performed for the National or State Governments.

2. ENGINEERING AND CONSTRUCTION.

Mechanical Plant.

Since the original installation of the heating and power plant of

the Bureau, three large laboratories have been added and a fourth is

in process of construction. During this time such special additions

have been made to the Bureau plant as space permitted. However,

the plant is not only being used to its full capacity, but at certain seasons of the year is greatly overtaxed. It is evident that the completion of the chemical laboratory authorized at the last session of

Congress, will necessitate enlargement and remodeling of the power

and heating system by the construction of an addition to the present

building, or a smaller one detached from it, to provide for additional

boiler and power plant space.

The Bureau has also outgrown the capacity of its refrigerating

plant originally installed at the establishment of the Bureau. The
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 95

necessity for the control of temperature and humidity in many tests and experimental problems, requires the installation of a larger

plant at the earliest possible moment. The general condition of the

power plant is far too inadequate.

Provision should also be made for the better handling of the

mail and express between the Bureau and the city, by the addition

of a small auto delivery wagon. The collection of samples of materials to be tested for the various Government bureaus and the

delivery of results have been seriously retarded by the lack of such

conveyance. This is often a serious matter in connection with the

award of contracts or the acceptance of deliveries.

The personnel of the engineering division should be augmented

by providing an additional assistant engineer, a fireman, and a

laborer.

Construction Facilities.

The care of the mechanical plant, of the buildings, and especially

the construction of special apparatus of all kinds, necessitates a

corps of mechanics skilled in the various kinds of construction.

Every investigation requires the construction of more or less special

apparatus involving mechanics skilled in the. construction of all

kinds of precision instruments. These services include plumbing

and steamfitting, electrical wiring, wood working, instrument making, glass blowing, and glass grinding—all are involved in both

investigational and testing work. In fact the Bureau's efficiency

depends very largely upon having services of this sort available.

Care of Buildings and Grounds.

The care of the buildings of the Bureau has been inadequate for

several years. This has been due in part to insufficient janitor service and in part to the lack of continuous supervision of that service.

It is hoped that the janitor service may be increased during the

coming year and that provision may be made for its proper

supervision.

The care of the grounds has become of sufficient importance to

warrant the continuous employment of a foreman. The funds available for the care of the grounds have been, insufficient to do any

grading or to begin the construction of permanent roads. This

will be partially taken care of during the coming year.

IV. RECOMMENDATIONS.

Buildings.

Attention is again called to the necessity of properly housing the

structural materials work, especially the branch of the work at

Pittsburgh, and which is temporarily located in buildings of the

War Department at the Arsenal grounds. These buildings are entirely unsuited for the purpose either as to location or character, and

the Bureau has considered it unwise to expend any funds on their

preparation as laboratories other than the barest necessities. Furthermore, the War Department has repeatedly asked for the vacation

of the building.

Every effort is being made by the Bureau to place its structural

work on a basis commensurate with its importance. Considerable
96 REPORT OF DIRECTOR OF BUREAU OF STANDARDS.

heavy equipment has been accumulated both at Pittsburgh and Washington, and more will be needed. Good work is being carried on at

both places but the large testing machines, furnaces, and other heavy

equipment should be brought together in a building designed for the

purpose and sufficiently large to accommodate all heavy equipment

of this kind. It is uneconomical and inadvisable to proceed with

the installation of permanent heavy equipment in temporary quarters.

Transverse Testing Machine.

Attention is again called to the necessity of adding to the Bureau's

equipment a large transverse testing machine capable of testing the

transverse strength of full-sized steel girders used in bridges and

buildings; also, brick, stone, and concrete arches, floor constructions,

etc. The late Alfred Noble, one of the most prominent engineers

that America has produced, made the following statement concerning

the necessity for the construction of such a machine

The use of steel and concrete in girders in the construction of bridges and

buildings is increasing rapidly. The calculations of strength of such girders are

to a large extent based on theory, not well checked by actual tests; such tests as have been made were on small girders, and the value of the results in determining the dimensions of large girders such as are now in common use is doubtful. It is questionable whether, on the one hand, many structures in daily use are not perilously near the breaking point ; or, on the other hand, whether

the structures are not built unnecessarily massive and costly.

There is therefore great need of a large testing machine for actually test- ing the strength of girders of large size. Such a machine, operated under the

direction of the Bureau of Standards, would soon repay its cost by inducing more economical and safer construction.

Since transmitting the original estimate for this machine, much

additional evidence has been secured, all indicating the great need on

the part of engineers for data that can only be obtained by a large

machine of this character. It is, therefore, recommended that a

sufficient sum be again included in the estimates to enable, the Bureau

of Standards to begin its design and construction.

Radio Laboratory.

Eadio conimunication has recently become of extreme importance

both in Government work and to the public. This method of communication is still largely in the experimental stages. Future progress and improvement in" radio communication will be in direct proportion to the progress that is made in the knowledge of the underlying scientific principles involved. Several departments of the

Government are deeply interested in maintaining this method of

communication on the best possible basis. To do this they will each

be compelled not only to keep in close touch with the progress of

other countries in this respect, but to undertake such scientific and

technical investigations as may be necessary. It would not only be

more economical^ but productive of much more efficient work to concentrate the laboratory work of the Government at one place hi a small laboratory especially designed for it. It has been agreed by

all of the Departments concerned, namely, War, Navy, Treasury,

Post Office, Agriculture, and Commerce, "that the location of the

laboratory at the Bureau of Standards would prove of great benefit

both as to the economical performance of the work and by its close
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 97

proximity to the scientific work of the Bureau, especially that of the

electrical division. An item of $50,000 for the construction of a

suitable radio laboratory, and another of $10,000 to enable the

Bureau of Standards to carry on that part of the radio work which

naturally falls to the Bui'eau in connection with the radio supervision work of the Department of Commerce, was included in the

estimate for the current year, but were not appropriated for. It is recommended that they be again submitted in the estimate for the

next fiscal year.

Additional Ground.

The recent opening of Van Ness Street north of the Bureau at a place not adjoining the Bureau's grounds, make it necessary to se- cure the small strip of land between that street and the north boundary of the Bureau site. Efforts were made without avail to secure the location of the street in a position adjoining the Bureau's property. It is also advisable to secure the narrow strip between the

Bureau and Tilden Street on the south.

Additional Scientific Assistance of the Minor Grades.

During the past two years the Bureau's work has grown far more

rapidly than its resources. This is especially true in consultation

and testing work for the Government. In several sections of the

Bureau it has been necessary to suspend all investigations in order

to care for the testing of materials purchased on Government contracts. This would not be so serious if suitable specifications and

methods of testing were in existence for the wide range of materials

to be tested; but it can truly be said that such is the case in only a very limited number of materials. It is felt that this situation can

be remedied to a large extent by a reasonable increase in the minor

assistants such as apprentices, aids, and assistants up to and including the grade of $1,400. A few of these men in each section could

almost double the Bureau's output of testing, and what is still more

important, allow more time on the part of advanced men for the

improvement of methods and specifications.

Clerical Services.

The clerical assistance of the Bureau has been entirely inadequate

for the past four years. So critical has this become during the past

year that it is a serious question as to whether the Bureau is not

very materially reducing the efficiency of all branches of its work by

the lack of anything like adequate clerical assistance. This is especially true in the case of property records, accounting, files, and

correspondence.

Skilled and Unskilled Labor.

The situation of the Bureau is such that it is impractical to secure economical contracts for small jobs of construction. These are continually arising in all kinds of experimental work. Their nature is

such that they require the supervision of the experts of the Bureau.

It is no uncommon matter when soliciting bids for this class of work

to receive them of three or four times the amount necessary. This

65301°—14 7
98 REPOBT OF DIRECTOR OF BUREAU OF STANDARDS

is due to the distance of the Bureau from the city, the necessity for

the supervision of the work on the part of the contractor, and his

hesitation to undertake work of a character unfamiliar to him. It

is therefore recommended that the Bureau staff of this class of

skilled and unskilled laborers be considerably increased.

Increase of Funds for Special Investigations.

Several of the special funds under which the Bureau is carrying on important work should be increased, namely, structural materials, testing and inspection of large scales, the public-utility fund,

and that for the investigation of the fire-resisting properties of

materials, and for the investigation of the causes of failure of railway materials.

Standard Materials.

In another part of this report attention is called to the necessity

of extending the preparation of standard samples of materials. The

Bureau is unable at present to prepare more than a few of the most

important. These samples are in great demand by a large number

of industries, as well as educational institutions. A special appropriation of not less than $4,000 should be asked for to provide for

the preparation of these samples. It should be kept in mind that

these samples are distributed at the cost of production, the greater

part of the expense of their preparation being returned to the

Treasury.

Investigation of Textiles, Paper, Leather, and Rubber.

The increased tendency on the part of the Government and the

public to purchase textiles, paper, leather, and rubber according to

specifications and tests, makes it necessary for the Bureau to develop

standards of quality and methods of testing. This is especially important in view of the fact that laws and regulations are rapidly

being prepared and enacted regarding the branding and quality of

these materials, both of which involve standards and methods of

testing. An item should therefore be included in the next estimates

to cover this work.

Investigation of Clay Products.

The pottery, brick, tile, terra cotta, and other industries engaged

in the production of clay products are greatly in need of reliable

and authoritative data concerning the properties of these products

and the materials which enter into them. In few industries is there

any greater opportunity of the improvement by the application of

precise measurements and of scientific knowledge of the nature of

the products. For this purpose it is recommended that a special

fund of $10,000 be included in the estimates.

Color Standards and Specifications.

The industries engaged in the manufacture of paper, textiles,

dairy products, oils, dyes, inks, and many others, are in urgent need

of such standards and the methods for their use. A special fund of

not less than $5,000 per year for three or four years would enable the

Bureau to take up the more important phases of color work.
REPORT OF DIRECTOR OF BUREAU OF STANDARDS. 99

Covering for Meter-Testing Tank.

The meter testing tank as constructed is in the open and is not

available for use in the winter or bad weather. These and other conditions make it desirable to inclose it by a light inexpensive cover- ing which will protect it and make it available in all kinds of

weather.

Repairs and Alterations.

The ftmds available for repairs and alterations should be increased

for repainting the walls of three of the larger buildings, together

with the external woodwork.

Respectfully,

S. W. Stratton, Director.

To Hon. William C. Redfield,

Secretary of Commerce.

o