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BULLETIN 



OF THE 



NATIONAL RESEARCH 

COUNCIL 



VOLUMES 
December, 1921, to August, 1922, inclusive 



• » 



Published by The National Research Council 

OF 

The National Academy of Sciences 

Washington, D. C. 

1921-1922 



CONTENTS 



Number i6 

Research laboratories in industrial establishments of the 
United States, including consulting research laboratories. 
Pp. 135. Originally compiled by Alfred D. Flinn. En- 
larged and revised by Ruth Cobb. 

Number 17 

Scientific papers presented before the American Geophysical 
Union at its second annual meeting. Pp. 108. 

Number 18 

Theories of magnetism. Report of the National Research 
Council Committee on Theories of Magnetism. Pp. 261. 
By A. P. Wills, S. J. Barnett, L. R. IngersoU, J. Kunz, 
S. L. Quimby, E. M. Terry, S. R. Williams. 







o 



Vol. 3. Part 1 DECEMBER, 1921 Number 16 



Bulletin 



OF THE 



National Research 

Council 



RESEARCH LABORATORIES 

IN INDUSTRIAL ESTABLISHMENTS 

OF THE UNITED STATES 

Including Consulting Research Laboratories 

Originally compiled by 
Alfbed D. Flinn, Secretary, Engineering Foundation 

Revised and enlarged by 
Ruth Cobb, Research Information Service 



Published by The National Research Council 

OF 

The National Academy of Sciences 
Washington, D. C. 

1921 



Announcement Concerning Publications 

« 

of the 

National Research Council 



The Proceedings of the National Academy of Sciences 

has been designated as the official organ of the National 
Research Council for the publication of accounts of research, 
committee and other reports, and minutes. 

Subscription rate for the "Proceedings" is $5 per yean 
Business address: Home Secretary, National Academy of 
Sciences, Smithsonian Institution, Washington, D. C. 

The Bulletin of the National Research Council 

presents contributions from the National Research Council^ 
other than proceedings, for which hitherto no appropriate 
agencies of publication have existed. 

The "Bulletin" is published at irregular intervals. The 
subscription price, postpaid, is $5 per volume of approxi- 
mately SCO pages. Numbers of the "Bulletin" are sold 
separately at prices based upon the cost of manufacture (for 
list of bulletins see third cover page). 

The Reprint and Circular Series of the National 

Research Council 

renders available for purchase, at prices dependent upon the 
cost of manufacture, papers published or printed by or for 
the National Research Council (for list of reprints and circu- 
lars see fourth cover page). 

Orders for the "Bulletin" or the "Reprints and Circulars" 
of the National Research Council, accompanied by remit- 
tance, should be addressed: Publication Office, National 
Research Council, 1701 Massachusetts Avenue, Washington, 
D. C. 



.^^^KRD coil 
MAY lo 1923 



«\^^L^.|4 



BULLETIN 

OF THE 

NATIONAL RESEARCH COUNCIL 

Vol. 3. Part 1 DECEMBER. 1921 Nombei 16 



RESEARCH LABORATORIES IN INDUSTRIAL ESTABLISH- 
MENTS OF THE UNITED STATES 

Including Consulting Research Laboratories 

Originally compiled by 
Alfred D. Flinn, Secretary, Engineering Foundation 

Revised and enlarged by 
Ruth Cobb, Research Information Service 



CONTENTS 

Introduction 1 

Alphabetical list of laboratories 4 

Index to subject classification of laboratories 88 

Subject classification of laboratories 94 

Address list of directors of research 121 

INTRODUCTION 

The demand for information concerning industrial research laboratories 
has indicated such a widespread interest in this subject that it seemed 
desirable to issue an early revision of the list contained in Bulletin of the 
National Research Council, number 2. The original publication was com- 
piled early in 1920 by Mr. Alfred D. Flinn, Secretary of the Engineering 
Foundation, with the assistance of Miss Ruth Cobb of the Research 
Information Service. It contains the names of nearly 300 laboratories in 
industrial establishments in the United States which had stated in direct 
correspondence that they were engaged in research. The present publica- 
tion has revised the original material as of August, 1921, and has added 
about 250 new names. 

As in the original list, all information here given has been obtained 
directly by correspondence, and statements are based upon information 
supplied by the laboratories. An endeavor has been made to follow the 
phraseology of the laboratories wherever possible and to print each name 



2 INDUSTRIAL RESEARCH LABORATORIES 

exactly in the style used by the company, with regard for spelling and 
abbreviations. 

No investigation has been made to ascertain the character of any 
laboratory listed nor the quality of work done. In order to avoid mistakes 
through misinterpretation, the laboratories were given the opportunity to 
approve or correct their material after it had been transcribed. During 
August and September the majority of companies availed themselves of 
this opportunity. 

Three methods were used to collect information about laboratories not 
originally listed: (a) Forms calling for corrections and additions were 
distributed widely with the first edition of the list, (b) Special requests 
for information were sent to over 200 companies believed to maintain 
research laboratories. These names were obtained through the generous 
cooperation of The Chemical Catalog Company, Inc., following its recent 
survey of chemical firms in this country, (c) A press notice of the forth- 
coming revision was sent to a selected group of technical and trade 
journals. This notice requested information from directors of research 
who had not already supplied it. 

Of the 300 laboratories originally listed all except seven responded to 
the appeal for a revision of the first statement. Fourteen other names 
were dropped because the firms replied that they no longer maintained 
research laboratories. Eleven had made new connections and appear here 
under different names. 

Laboratories connected with federal, state or municipal governments, 
or with educational institutions, were from the outset excluded from the 
inquiry, although frequently they are engaged upon investigations in 
industrial research. The concerns which are not actually supporting 
laboratories in their own works have not been included, nor have the 
associations maintaining fellowships in certain educational institutions. 
They are to be encouraged, but this compilation is limited to the labora- 
tories themselves, rather than organizations supporting research. 

The following information is given for each entry: name and address 
of company and address of laboratory if different from that of company ; 
name of director of research and number on his staff; chief lines of 
research work; special equipment, if any, or equipment of unusual 
character. 

In addition to the alphabetical list of laboratories, which carries all the 
information, there is given a subject classification. This classification 
combines the headings used in the scientific and commercial classifications 
of the first edition and thus eliminates some unnecessary duplication. 
These classifications were devised by members of the National Research 
Council, the Engineering Foundation and others interested in research 
work, and are kised in part upon the classifications used in Chemical 
Abstracts and Science Abstracts. They were revised and combined for 
this edition with the help of Dr. C. J. West. An alphabetical index of 
subjects and cross references provides a key to the classification. 

A copy of the headings used in the publication was sent to each labora- 



INDUSTRIAL RESEARCH LABORATORIES 3 

tory listed with the request that it check the subjects under which its 
name should appear. The suggestions of the laboratories were followed 
wherever possible. In this way the research activities of the companies 
by subject are more fairly represented than was possible when the material 
was all classified by someone unfamiliar with the detailed work of these 
laboratories. 

The geographical classification of the original edition has been dropped 
and in its place is given an alphabetical list of names and addresses of 
directors of research in the laboratories included in the bulletin. 

Corrections and additional information will be welcomed. 



4 INDUSTRIAL RESEARCH LABORATORIES 

ALPHABETICAL LIST OF LABORATORIES 
z. Abb6 Engineering Company, 50 Church St., New York, N. Y. 
(Designs pulverizing and grinding machinery.) Laboratory at 230 
Java St., Brooklyn, N. Y. 

Research sta^* H. F. Kleinfcldt and 3 men experienced in ma- 
chinery. 

Research work : Part time of 3 on the solution of problems which 
involve crushing, grinding, pulverizing, mixing, and sifting machinery. 
a. Abbott Laboratories, The, Chicago, 111. 

Research staff : A. S. Burdick, 8 chemists and 4 biologists. 

Research work: Three-fourths time of 12 on new anesthetics, 
hypnotics, antiseptics, and other chemical research ; animal pathology 
and bacteriology; pharmacology and investigations of new medicinal 
preparations. 

3. Abbott, William G., Jr., Wilton, N. H. (Research engineer.) 
Research staff: W. G. Abbott, Jr., i engineer, i mechanical expert 

and I chemist (part time). 

Research work : Three-fourths time on waste recovery, special ma- 
chinery and processes for mechanical, electrical, textile and chemical 
trades. 

4. Acheson Graphite Company, Niagara Falls, N. Y. (Graphite 
products, including dry-cell filler, paint* pigment, stove polish, pencils, 
electrodes, crucibles, tubes, muffles, graphite and grease lubricants.) 

Research staff: A. M. Williamson and 8 assistants. 
Research work: Three-fourths time of 9 on graphite, carbon and 
lubricants. 

5. Acme White Lead & Color Works, Detroit, Mich. 
Research staff : Clifford D. Halley, 4 chemists and 2 engineers. 
Research work : Full time of 7 on paints and varnishes. 

Aetna Explosives Company, Inc. See Hercules Powder Co., Em- 
porium Research Laboratory (p. 39). 

6. Allen-Bradley Co., 286 Greenfield Ave., Milwaukee, Wis. (Elec- 
tric controlling apparatus.) 

Research staff: Lynde Bradley, 3 chemists and i mechanic. 

Research work : Full time of 5 on resistance materials and insula- 
tion. 

Allied Dye & Chemical Corporation. See General Chemical Com- 
pany (p. 35). 

7. Aluminum Company of America, Oliver Building, Pittsburgh, Pa. 
Central Laboratory at New Kensington, Pa. Branch of the Research 
Bureau at Cleveland Plant of Aluminum Manufactures,- Inc. 

Research staff : Francis C. Frary and others. 
Research work : Aluminum production and utilization. 

8. American Agricultural Chemical Company, The. Agricultural 
Service Bureau, 92 State St., Boston, Mass. (Fertilizers.) Chemical 
laboratory at Carteret, N. J. 

Research staff: H. J. Wheeler, 9 agronomists and chemists, super- 
intendent of experiment farm, i expert photographer. 

Research work: Study of requirements of soils and crops where 



INDUSTRIAL RESEARCH LABORATORIES 5 

fertilizers are being introduced or have not been used ; study of citrus 
fruits and other special crops in Florida in connection with various 
types of soil ; experiments and demonstrations with fertilizers in Illi- 
nois, Iowa, Minnesota, New Hampshire, Wisconsin and other states. 
9. American Beet Sugar Company, Denver, Colo. Laboratory at 
Rocky Ford, Colo. 

Research staff: i chief, i director, i agricultural investigator, i 
economic entomologist, 2 factory chemists, and i experiment station 
assistant. 

Researcfi work: Full time of 5 on all agricultural phases of sugar 
beet improvement, including the analysis of irrigation waters and 
soils, study of rotations, cultural methods, seed breeding, and the in- 
vestigation of the life histories of economic insect pests. 

Equipment : Complete plant pathological and entomological equip- 
ment. Greenhouse for propagation and study of various economic 
phases of plant breeding, control of diseases, and observations on 
insect pest development and habits. 
xo. American Blower Company, 6004 Russell St., Detroit, Mich. 

Research staff: J. A. Watkins and 2 or more assistants. 

Research work: Full time of 3 on air propelling mechanisms, air 
conditioning apparatus, dehydrating or desiccating apparatus, con- 
veying of dust and waste material, heating and ventilating, forced and 
induced draft for combustion of all kinds of fuels and kindred lines 
where air movement forms the basis for desired results. 

Equipment: All kinds of instruments for measuring the pressure 
and flow of air, electric dynamometers for determining power ex- 
pended, electrical measuring instruments, instruments for deter- 
mination of the purity, density, humidity, temperature and pressure 
of the atmosphere, etc. 

XX. American Brass Company, The, Waterbury, Conn. Chemical, 
metallogn'aphic and metallurgical laboratory at Waterbury; physical 
and electrical testing laboratory at Ansonia. 

Research staff: William H. Bassett, 3 metallurgists, 2 chemists, 
I physicist and metallographer, i metallographer, 2 metallurgical 
engineers, i testing engineer and necessary assistants. 

Research work: One-third time of 11 on nature and effect of im- 
purities in copper and its alloys ; effects of mechanical working, heat 
treatment, corrosion and conditions of exposure. 

Equipment: Waterbury laboratory: metallographic equipment for 
study of heat treatment of non-ferrous metals and alloys ; Adam Hilger 
Quartz "D" spectroscope of high sensitiveness; facilities for produc- 
tion of special alloys, corrosion and other special tests. Ansonia : 200,- 
ooo-pound Olsen, 100,000-pound Riehle and smaller testing machines, 
covering physical testing of all materials down to very fine wire; 
fatigue and friction testing apparatus ; electrical apparatus for accurate 
resistance and conductivity tests. 

la. American Can Company, 120 Broadway, New York, N. Y. 
Laboratoiy at nth Ave. and St. Charles Rfoad, May wood, 111. 

Research staff: F. F. Fitzgerald, 2 assistant chemists, i metallur- 
gist, 2 food technologists, 2 analysts and 4 laboratory assistants. 

Research work: One-half time of 12 on cooperative work with 



6 INDUSTRIAL RESEARCH LABORATORIES 

packers of food products in investigating chemical changes taking 
place in food products and their influence upon the preservation of 
the food, its quality and its wholesomeness. Manufacturing opera- 
tions, including study of fluxes, white metal alloys, coals, oils and 
other materials. 

Equipment: Special apparatus for analysis of tinplate and solder 
for tin content ; apparatus for investigating tin cans, sealing them, etc. 

13. American Chemical and Manufacturing Corporatioiit Cranford, 
N.J. 

Research staff : Harry P. Taber and i assistant. 
Research work : Part time of 2 on animal and vegetable oils, resins, 
varnish gums and cellulose esters. 

14. American Chemical Paint Company^ 1126 S. nth St., Philadel- 
phia, Pa. 

Research staff: J. H. Gravell, 2 chemists, i engineer and i general 
utility man. 

Research work: Full time of 5 on rust-proof paints for iron and 
steel; scale and rust removal; high temperature paint; methods of 
preparing metals for painting, enameling and japanning ; water-proof 
and acid-proof barrel linings. 

25. American Cyanamid Omipany, 511 Fifth Ave., New York, N. Y. 
Has three plants and a laboratory at each but research and develop- 
ment work are being centralized at plant nearest New York. 

Research istaff: W. S. Landis, 5 skilled chemists and several as- 
sistants, as a minimum. Usually includes 10 or 15 skilled men being 
trained for operating positions in new processes. 

Research work: Full time of staff on fertilizers, nitrogen fixation, 
cyanide phosphates, potash, nitrogen compounds and derivatives. 
Much of the work done in the experimental plants and laboratories is 
development, rather than true research. 

Equipment: Apparatus is of commercial size; frequently a com- 
plete small commercial plant is leased for experimental work. 
x6. American Diamalt Company, 419 Plum St., Cincinnati, Ohio. 
Laboratory at Riverdale, Cincinnati, Ohio. 

Research staff: Joseph M. Humble and 5 chemists. 

Research work: Half time of 6 on diastatic and malt sugar prod- 
ucts in general. 
17. American Hominy Company^ 1857 Gent Ave., Indianapolis, Ind. 

Research staff: F. C. Atkinson and 10 to 12 assistants. 

Research work: Approximately half time of 12 on corn products. 
x8. American Institute of Baking, 1135 Fullerton Ave., Chicap^o, 111. 

Research staff : Harry E. Barnard, 2 chemists and i technician. 

Research work : Full time of 4 on special problems of baking and 
their investigation from the standpoint of mdustrial development; 
sanitation of bakeries. 

Equipment : Complete baking equipment, 
xg. American Optical Company, Southbridge, Mass. 

Research staff : Charles Sheard, i physicist, i physicist and phj^sical 
opticist, I physiological opticist, i astronomer, i general chemist, i 
physical chemist, i metallurgist and 7 assistants, including mechan- 
ician. 



INDUSTRIAL RESEARCH LABORATORIES 7 

Research work: Full time of 14 on metallurgical research in non- 
ferrous metals, especially on ability of metals and alloys to stand re- 
peated workings. Spectral transmission of glasses, for example, 
glasses to reflect or absorb infra-red. Optical designing in general, 
especially designing of scientifically correct ophthalmic lenses; also 
optical instrument designing. Abrasive material for grinding and 
polishing glass. Fusing together glasses of different types. 
Adhesives. Glass strength investigations. Retinal currents due to 
light stimulation. Relations between radiant energy and the eye. 
Problems of ocular refraction. Limits of visibility in ultraviolet. Also 
publishes American Journal of Physiological Optics. 

Equipment: Optical measuring apparatus for transmission in the 
ultraviolet, visible and infra red ; Zeiss metallographic outfit. 

20. American Radiator Conu)any, BufiFalo, N. Y. Laboratory at 1807 
Elmwood Ave., Buffalo, N. Y. 

Research staff: Frank B. Howell, with an average of 11 technicians 
and helpers. 

Research work: Approximately full time of 12 on apparatus for air 
warming and cooling, involving heating boilers for burning anthracite, 
bituminous, and lignite coals, coke, gas, oil, etc., for Europe as well as 
America. Radiators : induction, convection, radiation. Refrigeration. 

Equipment : Innumerable brick and steel chimneys of various sizes 
for determining accurately grate, fuel, ash, heating surface, flue sur- 
face and total draft tensions. 

21. American Radio and Research Corporation, Medford, Mass. 
(Wireless telegraphs and telephones.) 

Research staff: V. Bush, i engineer manager and 5 assistants. 

Research work : Full time of 7 on phenomena at radio frequencies, 
and other matters intimately connected with radio telegraphy and 
telephony. Also investigation of power factor correcting equipment. 

Equipment: Apparatus for measurements and research at high 
frequency, such as arcs, oscillating bulbs, generators and bridges. 

22. American Rolling Mill Co., The, Middletown, Ohio. 
Research staff : Wesley J. Beck, 2 consulting chemical and metal- 
lurgical engineers, i electrical engineer and assistants, i metallurgical 
engineer and 2 assistants and i chemical engineer and 4 assistants with 
routine chemists. 

Research work : Nine-tenths time of staff on corrosion of iron and 
steel ; alloys, paints, magnetic properties of iron and steel. 

23. American Sheet and Tin Plate Company, 210 Semple St., Pitts- 
burgh, Pa. 

Research staff : R. E, Zimmerman, 7 chemical engineers, 2 chemists, 
I physicist and i metallurgist. 

Research work : Full time of 12 on chemical engineering problems 
relating to the manufacture of sheet steel, tin plate, and galvanized 
sheets ; metallurgy, metallography and pyrometry as applied to these 
manufacturing processes. 

24. American Sugar Refining Company, The, 117 Wall St., New York, 
N. Y. Service Division. 

Research staff : A. V. Fuller and i assistant. 

Research work : One-half time of 2 on adaptability of various sugar 



8 INDUSTRIAL RESEARCH LABORATORIES 

cane products to special purposes ; causes of failure in manufacture of 
sugar products and their remedies, and development of new sugar food 
products. 

Equipment : A trade candy kitchen in conjunction with the labora- 
tory. 

American Telephone and Telegraph Company. See Western 
Electric Company, Incorporated (p. 84). 
35. American Trona Corporation, Trona, Calif. (Borax, potash, etc.) 

Research staff : R. W. Mumford, 2 chemical engineers and 5 chem- 
ists. 

Research work : Full time of 8 on study of the equilibrium between 
the chlorides, sulphates, carbonates and borates of sodium and potas- 
sium, development of proper evaporation methods for evaporating 
Searles Lake brine and manufacture of boric acid and borates. 

American Vanadium Co. See Vanadium Corporation of America 
(p. 82). 

26. American Window Glass Co.» Factory No. i , Arnold, Pa. 
Research staff : L. P. Forman, 4 chemists and 2 ceramists. 
Research work : One-third time of 7 on new developments in glass 

industry, and ceramic work. 

Equipment : Pyrometric apparatus ; high and low temperature elec- 
tric furnaces. 

27. American Writing Paper Co., Holyoke, Mass., Department of 
Technical Control. 

Research staff: F. C. Clark, director; Ross Campbell, assistant 
director; L. E. Roberts, in charge of research section; 4 research 
chemists, 5 chemical engineers, 3 analytical chemists and i laboratory 
helper. 

Research work: Full time of 9 on new fibres, new paper-making 
processes, improvements in present processes ; mill experimental work 
to improve present processes and effect economies in operation. 

Equipment : 2 12-pound Noble and Wood beaters, 4 model digesters, 
special machine for testing tub size. Complete experimental paper 
mill with 66-inch combination Fourdrinier and cylinder paper ma- 
chine ; small model paper machine producing a sheet of paper 4 inches 
wide. 
aS. Amoskeag Manufacturing Company, Manchester, N. H. (Textile 

mills.) 

Research staff: William K. Robbins, 3 chemist^ and i laboratory 
helper. 

Research work: Small part time of 4 on waste recovery, dye, 
bleaching, sizing and testing, problems. Semi-commercial scale ex- 
periments in plant. 

Equipment: Exposure boards for light and weather tests, cloth 
and yarn breaking machines. 
29. Anaconda Copper Mining Co., Anaconda, Mont. 

Research staff : F. F. Frick, 9 assistants and 10 to 20 non-technical 
assistants. 

Research work : Full time of 20 to 30 on problems connected with 
the industry. 



INDUSTRIAL RESEARCH LABORATORIES 9 

30. Andrews, A. B., State Assayer, Lewiston, Me. 
Research staff: A. B. Andrews, 2 chemists and i engineer. 
Research work: Two-thirds time of 3 on paper, ceramics, naval 

stores and electrical conductivity. 

Equipment: Grinding equipment including i-ton ball mill and 
digester, beater and calendar for paper. 

31. Ansbacher, A. B., & Company, 527 Fifth Ave., New York, N. Y. 
Laboratory at 310 N. 7th St., Brooklyn, N. Y. 

. Research staff : D. N. Barad and 2 assistant chemists. 

Research work : Dry colors and inorganic pigments. 
3a. Ansco Company, Binghampton, N. Y. (Photographic equipment 
and supplies.) 

Research staff: Alfred B. Hitchins and 5 trained men. 

Research work : Full time of 6 on photographic work. 

Equipment: For photographic emulsions, spectroscopic work, 
spectro-photogn'aphy, photometry and photo-micrography, testing of 
dyes and color filters, polariscopic and refractometric work; high 
temperature oveins. Experimental laboratory fbr motion picture 
work. 

33. Ansul Chemical Company, Marinette, Wis. (Liquified anhydrous 
sulphurous acid.) 

Research staff : H. V. Higley and i chemical engineer. 

Research work : Three-fourths time of 2 on relation of anhydrous 
sulphur dioxide to oils, metals and other materials; development of 
allied products for manufacture ; study of customer's special problems 
of the use of sulphur dioxide in bleaching, deodorizing, disinfecting, 
mechanical refrigerating machines and chemical manufacturing. 

Equipment : Special apparatus for sulphur dioxide analysis and for 
plant control work. 

34. Arlington Mills, Lawrence, Mass. (Worsted textiles.) 
Research staff : Hugh Christison, 3 chemists and 3 assistants. 
Research work : Problems connected with the manufacture of tex- 
tiles in the application of dyestuffs. 

35. Armour Fertilizer Works, 209 W. Jackson Blvd., Chicago, 111. 
Research staff : M. Shoeld, 3 chemists and 2 engineers. 
Research work : Full time of 6 men on general research relating to 

fertilizer industry. (Research work at present interrupted.) 

Equipment: Special type electric furnaces; special type fuel fired 
furnaces. 

36. Armour Glue Works, 3ist Place and Benson St., Chicago, 111. 
Laboratory serves also Armour Soap Works, Armour Ammonia 
Works, Armour Curled Hair Works, and Armour Sandpaper Works. 

Research staff: J. R. Powell, 6 chemists, 6 laboratory assistants and 
4 helpers. 

Research work : Full time of i and part time of 2 on investigation 
of some of the plant processes. Work is principally analytical, for 
plant control. 

37. Art in Buttons, Incorporated, Rochester, N. Y. 

Research staff : F. W. Ross, chemical research ; Richard Stanforth, 
industrial research, and assistants. 



10 INDUSTRIAL RESEARCH LABORATORIES 

Research work : Full time on problems incident to vegetable ivory 
button manufacturing. 

Associated Factory Mutual Fire Insurance Companies. See Fac- 
tory Mutual Laboratories (p. 32). 

38. Atlantic Dyestuff Company, 88 Ames Building, Boston, Mass. 
Research staff : A. C. Burrage, Jr., and 3 assistants. 

Research work : Part time of 4 on intermediates and dyes. 

39. Atlantic Refining Company, The, 3144 Passyunk Avenue, Phila- 
delphia, Pa. (Petroleum products.) 

Research staff : T. G. Delbridge, 5 chemical engineers, 12 chemists, 
I physicist and 18 assistants. Mechanical and electrical engineering 
staffs collaborate with laboratory. 

Research work: Three-fourths time of 37 on manufacturing 
methods of petroleum refinery, including study of manufacturing 
equipment and of equipment for testing. 

Equipment: Laboratory-scale petroleum refinery, together with 
complete equipment for study of petroleum products; large scale 
manufacturing apparatus in the plant is at disposal of laboratory staff. 
Atlas BaU Company. See S. K. F. Industries, Inc. (p. 72). 

40. Atlas Powder Co., Wilmington, Del. (Explosives, leather cloth, 
lacquers and heavy chemicals.) Maintains three laboratories for re- 
search. 

Research staff: R. L. Hill, Re)molds, Pa., G. C. Given, Stamford, 
Conn., F. Bonnett, Jr., Landing, N. J., and 30 chemists. 

Research work: Full time of 33 on explosives of all kinds, caps, 
electric detonators, leather cloth, lacquers and miscellaneous chem- 
icals. 

Equipment : Designed for experimental work on explosives, leather 
cloth and lacquers. 

41. Ault & Wiborg Company, The, Cincinnati, Ohio. (Lithographic 
and letter press inks, ink varnishes, dry colors and dryers ; varnishes, 
lacquers and enamels ; typewriter ribbons and carbon paper ; writing 
fluids, pastes and mucilages ; dealers in all lithographic supplies.) 

Research staff : Robert W. Hilton and 3 research chemists. 

Research work: Full time of 4 on pigments, varnishes, ribbons, 
carbon paper, lacquers and enamels. 

4a. Avri Drug & Chemical Company, Inc., 421 Johnston Ave., Jersey 
City. N. J. 

Research staff : L. M. Avstreih and i assistant. 

Research work: Pharmaceutical, technical and analytical chem- 
istry. 

43. Babcock & Wilcox Co., The, Bayonne, N. J. (Steam engine 
boilers.) 

Research staff: J. B. Romer and 7 assistants. 

Research work : Full time of 2 and part time of 4 on development 
of refractory materials, embrittlement of steel, aluminum coating on 
steel and betterment of boiler practice. 

Equipment: Furnaces and apparatus for pyrometer and thermom- 
eter calibration; 150,000-pound Riehle testing machine; Upton-Lewis 
torsional and alternate bending machine; Brinell machine; sclero- 



INDUSTRIAL RESEARCH LABORATORIES 11 

scope ; special equipment for refractories research ; special equipment 
for investigation of hydrogen embrittlement in steel. 

44. Babcock Testing Laboratory, 803 Ridge Road, Lackawanna, N. Y. 
Research staff: S. C. Babcock, Bartlett Ramsdell, i chemical en- 
gineer, I chemist and i helper. 

Research work : One-half time of S on driers for paint, varnish and 
printer's ink trade ; by-products utilization, soap, gums, oils and waxes. 

Equipment: Small scale unit (200-pound) for production of soap, 
driers, etc. Destructive distillation equipment. 

45. Baker & Co., Inc., Newark, N. J. (Refiners and workers of plati- 
num, gold and silver.) 

Research staff: F. Zimmerman, chemical department, and 11 as- 
sistants. F. E. Carter, physical department, and 4 assistants. 

Research work : Large part of time of 17 on chemical research, and 
on production and application of precious metal and other alloys. 

Equipment: Ajax-Northrup induction furnace, Arsem furnace, 
metallographic outfit, Brinell hardness machine, Erichsen testing ma- 
chine, Kelvin bridge, precision potentiometer. 

46. Baker, J. T., Chemical Co., Phillipsburg, N. J. 
Research staff : Wm. P. Fitzgerald and 3 assistants. 

Research work: Full time of i on methods of testing reagents, 
methods of manufacture, etc. 

47. Baldwin Locomotive Works, The, Philadelphia, Pa. 
Research staff: H. V. Wille, 2 chemists and 7 assistants. 
Research work : Small part time of 10 on problems connected with 

the plant. 

Equipment : 4 Olsen testing machines up to 600,000 pounds 
capacity; Brinell machines and scleroscope. 

48. Banks & Craig, 51 East 42nd St., New York, N. Y. (Consulting 
Engineers and Chemists.) 

Research staff : Henry W. Banks, 3rd, and assistants. 

Research work : Food dehydration, food products and processes of 
food manufacture ; organic colloids and engineering problems in con- 
nection with water supply, sewage disposal, sanitation, etc. 

49. Barber Asphalt Paving Company, The, Philadelphia, Pa. 
Research staff: Charles N. Forrest and 15 assistants. 

Research work: Part time of 16 on application of asphalt and 
petroleum to commercial purposes. 

Equipment : Miniature oil refinery and complete laboratory equip- 
ment for chemical and physical testing of bituminous materials, 

50. Barber-Colman Company, Rockford, 111. (Small tools, machine 
tools and textile machinery.) 

Research staff : 2 chemists and i engineer. 

Research work : Approximately one-half time of 3 on improvements 
on cutting tools, alloy steels and special steels. 
Equipment: Complete metallographic equipment. 

51. Barrett Company, The, 4o Rector St., New York, N. Y. (Coal 
tar products.) Research Department at the New York office. J. M. 
Weiss, Manager of Research Department. Research laboratories at 
Edgewater, N. J. Chemical Department for the manufacture of re- 
fined coal tar products at Frankford, Philadelphia. Research on 



12 INDUSTRIAL RESEARCH LABORATORIES 

operating processes also carried on at Frankford.' A works laboratory 
at each of the 35 tar plants. 

Research staif (Edgcwater laboratory) : C. R. Downs, chief 
chemist, C. G. Stupp, assistant chief chemist, 40 chemists and chemical 
assistants, 5 engineers and 20 other men. Special products depart- 
ment, under direct control of research department, employs 20 process 
men and mechanics. 

Research work: Full time of 65 on problems in connection with 
improvement of products or processes, and development of new uses 
for normal products. General manufacturing department undertakes 
many experimental engineering problems, for which research depart- 
ment acts in consulting capacity. 

Research laboratories occupy 18,000 square feet; adjoining is a 
40- X 50-foot building for experimental plant operations. Special prod- 
ucts department buildings occupy about 10,000 square feet additional 
space. 

5a. Bausch & Lomb Optical Co., Rochester, N. Y. (Lenses and 
optical instruments.) 

Scientific Bureau 

Research staff: Hermann Kellner, 15 optical engineers and physi- 
cists and 6 laboratory assistants. 

Research work: Three-fourths time on development of optical 
apparatus: ophthalmic optics, microscope optics, photographic and 
projection apparatus, photometers, spectrometers, glass making prob- 
lems, etc. One-fourth time on development of manufacturing 
methods, testing apparatus, etc. 

Equipment: Complete equipment of optical instruments. 

Chemical Laboratory 

Research staff : Frank P. Kolb, 3 chemists and 2 assistants. 

Research work: One-half time on emery and rouge washing and 
grading, grinding and polishing experiments, cements, fillers, glass 
washing, glass silvering, metal plating. 

53. Beaver Board Companies, The, Beaver Road, Buffalo, N. Y. 
(Beayerboard and other wallboards for buildings.) 

Reisearch staff: H. F. Gardner, 20 chemists, 2 engineers and 40 
inspectors, testers and laboratory assistants. 

Research work: One-fourth time of 63 on pulp and board mill, 
wallboard, asphalt roofing and gypsum products. 

54. Beaver Falls Art Tile Company, Beaver Falls, Pa. 

Research staff : George E. Sladek, i ceramic chemist and 2 labora- 
tory assistants. 

Research work: Full time of 3 on factory control work, raw ma- 
terial testing, equipment testing and research for the betterment of 
the product. 

Equipment: Miniature plant, microscopic equipment for petro- 
graphic work. 

Beaver Valley Glass Co. See Fry, H. C, Glass Company (p. 34). 

55. Beckman and Linden Engineering Corporation, Balboa Buildmg, 
San Francisco, Calif. 

Research staff: J. W. Beckman, H. E. Linden, and a varying num- 
ber of chemists, physicists and assistants. 



INDUSTRIAL RESEARCH LABORATORIES 13 

Research work : Full time of staff on chemical, electrochemical and 
organic problems; salts occurring in natural brines; chemistry of 
barium and strontium salts ; electrolytic manufacture of metallic mag- 
nesium directly from its oxides ; cracking of oils by high-tension dis- 
charges. 

Equipment: Large .motor-generator set for direct-current elec- 
trolysis and transformers for high-tension work ; lOO kw. electric fur- 
nace suitable for experimental purposes. 

56. Beebe Laboratories, Inc., 161 3rd St., St. Paul, Minn. 
Research staff: W. E. King, i expert biological chemist, i phar- 
maceutical chemist, 6 bacteriologists and a number of technical 
workers and assistants. 

Research work : Approximately one-third time of 9 on development 
of new biological products, therapeutic agents, and modification and 
direction of processes of manufacture. Studies in bacteriology, im- 
munology, serology, biological and pharmaceutical chemistry. 

Equipment: Specially equipped for chemical, bacteriological and 
serological work, and animal experimentation. 

57. Belden Manufacturing Company, 23rd St. and Western Ave., 
Chicago, 111. (Rubber insulated wires and cables, coil-winding ma- 
chines, electromagnets and similar products.) 

Research staff: J. V. Van Buskirk. 

Research work : Problems relating to own industry. 

58. Bennetts' Chemical Laboratory, 1 142 Market St., Tacoma, Wash. 
(Analytical and consulting chemists, assayers and metallurgists.) 

Research staff: B. H. Bennetts, 4 chemists and i metallurgist. 

Research work : Part time of 6 on concentration of manganese ores 
of Pacific Coast. Atomizing of copper, zinc and aluminum. Agricul- 
tural chemistry. 

Equipment: Metal atomizing plant for copper, zinc and aluminum. 

59. Berry Brothers, Inc., Detroit, Mich. (Varnishes and paint spe- 
cialties.) 

Research staff : John F. Thomas and 3 chemists. 
Research work: One-third time of 4 on paint vehicles, varnishes 
and shellacs. 

60. Bethlehem Shipbuilding Corporation, Ltd., Union Plant, San 
Francisco, Calif. 

Research staff : S. R. Thurston and i assistant chemist. 

Research work : On improvement of strength and homogeneity of 
non-ferrous alloys. 

Equipment: Low voltage generator, Olsen automatic and auto- 
graphic universal testing machine of 200,000 pounds capacity ; Shore 
scleroscope, Brinell hardness apparatus. 

61. Betz, Frank S., Company, Henry and Hoffman Sts., Hammond, 
Ind. (Electric X-ray apparatus, hospital, surgical and dental sup- 
plies.) 

Research staff : P. M. Phillips and i assistant chemist. 

Research work : One-fourth time of 2 chemists on improvement of 
existing formulas of pharmaceutical products; development of new 
ideas in drug and toilet preparations; research to improve plant 
methods. Field covered: Syrups, elixirs, tinctures, fluid extracts, 



14 INDUSTRIAL RESEARCH LABORATORIES 

solid extracts, mixtures, ointments, suppositories, compressed coated 

and hypodermic tablets and lozenges. 

6a. Bloede, Victor G., Co., Station D, Baltimore, Md. (Chemicals.) 

Research staff: Victor G. Bloede, 4 chemists and assistant. 

Research work: Full time of 6 on developing adhesive products 
including dextrines, vegetable glues and special hydrolyzed starch 
products, and developing special sizings and gums for textile, carpet, 
wall paper manufacturing purposes, etc. 

Equipment: Special dextrinizing and hydrolyzinpf apparatus and 
facilities for testing and developing vegetable adhesives and sizings ; 
also machinery for testing out these products on a commercial scale. 

63. Bond Manufacturing Corporation, Monroe and Fifth Sts., Wil- 
mington, Del. (Bottle seals.) 

Research stail: William G. Bond, i engineering chemist and 2 
engineers. 

Research work: Full time of 4 on industrial problems connected 
with manufacture of composition cork, collapsible tubes and bottle 
crowns. 

64. Boonton Rubber Manufacturing Company, Boonton, N. J. (Elec- 
trical insulation and molded products.) 

Research staff : R. W. Seabury, i chemist, i electrical engineer and 
I mechanical engineer. 

Research work: One-third time of 4 on such problems as non- 
carbonizing molded insulation for high-tension automobile ignition 
apparatus; synthetic resins. Development of satisfactory insulation 
for high frequency, and commercial tests for same. 

Equipment : 100,000-volt testing transformer ; special apparatus for 
coating paper and fabric with resins in solution. High frequency 
phase displacement testing apparatus. 

65. Borromite Co. of America, The, 105 W. Monroe St., Chicago, 111. 
(Water softening systems.) Laboratory at 54 E. i8th St., Chicago, 111. 

Research staff: John A. Montgomery, 3 chemists and 3 engineers. 

Research work : Approximately one-half time of 7 on water soften- 
ing and equipment. A natural zeolite is employed as the water 
softening medium. 

66. Borrowman, GecK'ge, 130 N. Wells St., Chicago, 111. (Chemist.) 
Research staff : George Borrowman and i chemist. 

Research work: One-half time of 2 on materials of engfineering, 
such as waters, fuels, metals, cements, paints and clays. 

Boston Biochemical Laboratory, Inc., The. See Skinner, Sher- 
man & Esselin, Incorporated (p. 72). 

67. Bowker Insecticide Company, 49 Chambers St., New York, N. Y. 
(Insecticides and fungicides.) Laboratory at Everett, Mass. 

Research staff : Firman Thompson and i chemist. 
Research work : Full time of 2 on insecticides, fungicides and dis- 
infectant^. 

68. Boyer Chemical Laboratory Company, 940 N. Clark St., Chicago, 
111. (Private label chemical specialties and manufacturing chemists 
for the wholesale trade.) 

Research staff : A. D. Boyer, i chemist and i laboratory assistant. 



INDUSTRIAL RESEARCH LABORATORIES 15 

Research work: One-third time of 3 on varnishes, oils, waxes, pol- 
ishing materials, gums, disinfectants, etc. 

69. Brachy E. J., and Sons, 215 W. Ohio St., Chicago, 111. (Candies.) 
Has a laboratory for control and research and a manufacturing labora- 
tory. 

Research staff : C. O. Dicken and 3 chemists. 

Research work : One-third time of 4 on improvement of analytical 
methods and problems in manufacture of candy. 

70. Bridgeman-Russell Company, iioo W. Superior St., Duluth, Minn. 
Research staff: Benjamin F. Eichinger and 2 or more assistants. 
Research work : One-half time of 2 on chemical and bacteriological 

problems of manufacture of all dairy products, including sanitation, 
standardization and testing new methods of manufacture. 

Equipment: Highly perfected equipment for complete chemical 
and bacteriological analysis of all dairy products, water and food. 

71. Bridgeport Brass Company, Bridgeport, Conn. 

Research staff: W. R. Webster, i metallurgist, i mechanical en- 
gineer, 3 chemists, and 5 assistants. 

Research work: Full time of 2 and one-half time of 3 on general 
problems incidental to manufacture and fabrication of a large variety 
of alloys. A large amount of research work is done with the coopera- 
tion of the operating departments in the factories. 

Equipment : Apparatus for testing free cutting qualities of metals. 
7a. Brooklyn Union Gas Company, The, 176 Remsen St., Brooklyn, 
N.Y. 

Research staff: E. C. Uhlig, 2 assistant chemists, i chemical en- 
gineer, 9 analysts, 3 photometric inspectors, 21 gas testers and i 
photographer. 

Research work: Part time of 38 on problems of manufacture and 
distribution of gas. 

Unusual equipment: Apparatus for experimental gasification of 
oils ; photometer for spherical candle power of lamps. 
73. Brown Company, Portland, Me. Formerly Berlin Mills Com- 
pany. Mills: Berlin, N. H., and La Tuque, P. Q.; laboratory, Berlin, 
N. H. (Paper, sulphate and sulphite fiber, chemicals and lumber.) 

Research staff: Hugh K. Moore, 28 graduate chemists, i mechani- 
cal engineer, 2 technical photographers, and 10 chemical assistants. 

Research work : Full time of 27 on work including following sub- 
jects : improvements in the various mill processes of sulphite and sul- 
phate pulp making ; study of commercial electrolytic cells ; plant im- 
provements in the hydrogenation of oils and laboratory study of the 
process ; production of liquid chlorine, bleach powder by a continuous 
process, and acetylene tetrachloride; drying and impregnation of 
fiber tubes; production of alcohol by fermentation of hydrolyzed 
wood waste and sulphite waste liquor; properties of SO, solutions; 
study of physical and chemical properties of wood pulp, the beating 
process, testing of pulp and paper; performance of paper machines; 
study of lubrication problems; recovery and utilization of para- 
cymene; performance of steam boiler equipment; preservation of 
wood and pulp; purification of sulphate turpentine; study of color 



16 INDUSTRIAL RESEARCH LABORATORIES 

measurement; determination of characteristics of gas-absorption 
towers ; new uses for evaporated sulphite waste liquor. 

Equipment : 100,000 K. v. a. transformers and switchboard for elec- 
tric furnace work ; Audiff ren-Singrun refrigerating machine ; constant 
temperature and humidity apparatus for pulp and paper testing ; high 
pressure gas compressor. 

74. Brown & Sharpe Mfg. Co., Providence, R. I. (Machinery and 
tools.) 

Research work : On gray iron. 

75. Brunswick-Balke-CoUender Co., The, Muskegon, Mich. (Me- 
chanical and hard rubber products.) 

Research staff: A. Brill and 3 men. 

Research work: One-fourth time of 4 on rubber, glue and wood- 
working. 

76. Buchanan, C. G., Chemical Company, Station H, Cincinnati, Ohio. 
(Case hardening and carbonizing compounds.) Laboratory at Baker 
Ave., Norwood, Ohio. 

Research staff: R. F. Catherman, i electrical engineer and i 
chemist. 

Research work: Variable amount time of staff on metallic salts, 
pigments, industrial chemicals and their application in the various 
industries. 

77. Buckeye Clay Pot Co., Bassett and Ontario Sts., Toledo, Ohio. 
(Fire-clay products.) 

Research staff: W. K. Brownlee. 

Research work: Two-thirds time of i on tests of clay including 
determinations of dry transverse strength, water of plasticity, linear 
drying shrinkage, screen analysis for fineness, etc., also melting point, 
ability to withstand load at high temperatures, porosity, linear burn- 
ing shrinkages, burned strength, and other properties of burned clay. 

Equipment : For making both routine and special tests of clays. 

78. Buffalo Foundry and Machine Co., 1543 Fillmore Ave., Buffalo, 
N. Y. (Vacuum dryers, evaporators and industrial chemical appa- 
ratus.) 

Research staff: Willard Rother, metallurgical and physical test- 
ing department; D. J. Van Marie, chemical department; Charles 
Lavett, vacuum laboratory and testing departments ; 2 assistant chem- 
ists and 5 assistant engineers and operators. 

Research work : Small part time of 10 on practical experiments on 
materials furnished by customers to determine in advance what can 
be done by means of vacuum apparatus. 

Equipment: Completely equipped metallurgical, chemical and 
testing laboratories. 

79. Burdett Manufacturing Company, St. Johns Court at Fulton St., 
Chicago, 111. (Oxygen and hydrogen gas generating apparatus.) 

Research staff: J. B. Burdett and i chemist. 

Research work: Full time of 2 on rates of diffusion of gases, ex- 
plosive limits of gases, effect of electrolytic action incident to decom- 
position of water on various materials used in construction (steel, 
rubber and asbestos) development of special compounds for per- 



INDUSTRIAL RESEARCH LABORATORIES 17 

manent resistance to such action and to action of comparatively strong 
alkaline solutions. 

Burke Tannery. See International Shoe Co. (p. 44). 

80. Butterworth-Judson Corporation, Newark, N. J. (Chemicals, 
intermediates, dyes.) 

Research staff : A. Riker, Jr., 6 chemists and 2 helpers. 

Research work : Full time of 9 on problems relating to dye manufac- 
ture. 

Equipment: Particularly adapted for work on intermediates, dyes, 
acids and heavy chemicals, including semi-commercial scale apparatus. 

81. Byers, A. M., Company, Pittsburgh, Pa. (Wrought iron pipe, 
oil well tubing and casing.) 

Research staff: James Aston, several metallurgists and chemists, 
and assistants. 

Research work : One-half time of staff on corrosion and protective 
coatings of iron ; development of wrought iron. 

Equipment: Apparatus for corrosion tests and for determining 
physical characteristics. Electric furnace and auxiliary equipment for 
experimental heats of iron. 
8a. Cabot, Samuel, Inc., 141 Milk St., Boston, Mass. 

Research staff: Samuel Cabot and i assistant. 

Research work: One-third time of 2 on coal tar distillates, dis- 
infectants, paints, stains, varnishes. 

83. Calco Chemical Company, The, Bound Brook, N. J. 
Research staff : M. L. Crossley and 22 chemists. 

Research work : Full time of 23 and part time of plant engineers on 
intermediates, dyes and pharmaceuticals, including fundamental prob- 
lems of the reactions involved, development of new processes and 
plant improvement. 

84. California Fruit Growers Exchange, Box 518, Corona, Calif. 
Research staff : C. P. Wilson and 2 chemists. 

Research work: Five-sixths time of 3 on by-products from citrus 
fruits ; chemical problems connected with production, preparation and 
sale ol citrus fruits. 

85. California Ink Company, Inc., Camelia and 4th Sts., Berkeley, 
Calif. (Printing and lithographic inks, varnishes and rollers.) 

Research staff: E. T. Frickstad and 3 chemists. 
Research work : One-half time of 4 on oil, varnish, dry color, dyes, 
intermediates and inks. 

86. Calumet & Hecla Mining Company, Calumet, Mich. Laboratory 
at Lake Linden, Mich. 

Research staff: C. H. Benedict with an average of 4 assistants. 
Research work : Hydrometallurgy of copper. 
Equipment : Large scale operation in leaching, flotation, etc. 
Carbide and Carbon Chemical Corporation. See Union Carbide 
and Carbon Research Laboratories, Inc. (p. 78). 

87. Carborundum Company, The, Niagara Falls, N. Y. (Abrasive 
and refractory materials.) 

Research staff: M. L. Hartmann, 15 chemical and electrochemical 
engineers, 7 assistants with technical experience and 4 non-technical 
helpers. 



18 INDUSTRIAL RESEARCH LABORATORIES 

Research work : Full time of 27 on problems relating to abrasives 
and refractories. Development of new products and improvement of 
present processes. Semi-commercial scale equipment is available in 
electric furnace laboratory. Especially interested in study and de- 
velopment of the specialized refractory materials. Problems also in- 
clude those relating to adhesives, rubber, shellac, paper and cloth. 

88. Cam^e Steel Company, 1054 Frick Annex Building, Pittsburgh, 
Pa. Central Research Bureau for United States Steel Corporation. 

Research staff: J. S. Unger; chemists, physicists, engineers and 
assistants selected from works staffs as needed. 

Research work: At steel plants, covering problems of steel manu- 
facture, properties of refractories and other materials used in steel 
manufacture, by-products and the testing of finished products, par- 
ticularly service tests. 

89. Canu Chemical Company, La Salle, 111. (Permanganates, man- 
ganese salts, titanium salts, saccharine, toluene sulphonamides and 
their chlorine derivatives, benzoates.) 

Research staff : Karl Kleimenhagen and 7 men. 
Research work: Three-fourths time of 8 on development of pro- 
cess for producing chemicals manufactured by the company. 

90. Case Research Lab<Mratory, Auburn, N. Y. 

Research suff: Theodore W. Case, 3 technical men and several 
assistants. 

Research work: Full time of at least 4 on problems in light and 
photo-electricity. 

Equipment: Apparatus for photo-electric work. 
92. Caulk, L. D., Company, The, Milford, Del. (Dental materials.) 

Research staff : Arthur W Gray, director physical research ; Paul 
Poetschke, director department of chemistry; D. Anton Zurbrigg, 
director clinical department. 

Research work: Properties and application of materials used in 
dentistry. 

Equipment : Chemical and physical apparatus for determining the 
properties of dental products of all kinds. Equipment for bacteriolog- 
ical, biological and chemical investigation of dental problems. 

92. Celite Products Company, Van Nuys Building, Los Angeles, 
Calif. (Manufacturers and distributors of heat insulating materials, 
filtering materials and mineral fillers.) Laboratory at Lompoc, Calif. 

Research staff: P. A. Boeck, 2 chemical engineers, i chemist and 
4 assistants. 

Research work: Approximately three-fourths time of 10 on filtra- 
tion of industrial liquids, measurement of thermal insulation and ca- 
pacity of heat insulating materials and microscopical analysis. 

Equipment: Complete equipment for pressure and gravity filtra- 
tion of industrial liquids, apparatus for the determination of thermal 
conductivity of insulators and furnace equipment for refractory 
testing. 

93. (Antral Dyestuff and Chemical Co., Plum Point Lane, Newark, 
N. J. (Coal tar colors and intermediates.) 

Research staff : John Prochazka, 14 chemists and assistants. 



INDUSTRIAL RESEARCH LABORATORIES 19 

Research work: Nine-tenths time of 15 with assistants on dye- 
stnffSy pharmaceuticals, and coal tar intermediates. 

Equipment: Separate experimental factory 60x40 with adequate 
machinery, such as suitable stills, filter presses and autoclaves for 
small scale manufacture. 

94. Central Scientific Company, 460 East Ohio St:, Chicago, 111. 
(Physical, chemical, agricultural and biological apparatus.) 

Research staff : Paul E. Klopsteg and 2 assistants. 
Research work: Full time of 2 on development of new apparatus 
and instruments, and improvement in devices already manufactured. 

95. Champion Ignition Company, Flint, Mich. 

Research staff : T. G. McDougal and 2 ceramic engineers. 

Research work : Three-fourths time of 3 on perfection of high tem- 
perature insulation (electrical) ; super-refractory furnace linings for 
own use ; continuous high temperature factory processes. 

Equipment: Laboratory and factory facilities for operations up to 
1800 C. Equipment for measuring electrical leakage up to 900 C. 

96. Champion Porcelain Company, Detroit, Mich. Formerly Jeffery- 
Dewitt Co. (Porcelain products.) 

Research staff: Frank H. Riddle and 12 assistants. 

Research work: One-third time of 13 on ceramic investigations 
necessary in ignition and high tension porcelain manufacture includ- 
ing development of bodies, methods of testing, manufacturing, etc. 
Also development of furnaces, special refractories and similar equip- 
ment. 

Equipment: Electrical equipment for tests of porcelains, for igni- 
tion and high tension work, special furnaces for tests of refractories. 

97. Charlotte Chemical Laboratories, Inc., 606 Trust Building, Char- 
lotte, N. C. 

Research staff: FJ. Bartholomew, i chemist, 2 chemical engineers. 

Research work: Two-thirds time of 6 on development of plant 
processes. 

Equipment: Electric vacuum furnaces. Large capacity grinding 
units. 

98. Chase Metal Works, Waterbury, Conn. (Brass, bronze, copper 
and nickel, silver, rod, wire, sheet and tubing.) 

Research staff: Harry George, 3 chemists, i electrochemist, 3 
metallurgists and 8 assistants. 

Research work : One-fifth time of 16 on improvement of properties 
and methods of manufacture of copper-zinc alloys ; also investigation 
of steels, lacquers, fuels and oils. 

Equipment: 100,000-pound Olsen testing machine, 50,000-pound 
Riehle testing machine, 10,000-1,000-pound Olsen wire testing ma- 
chine, Brinell machine, Spring tester, scleroscopes ; metallographic 
equipment, electric annealing muffles with electrically controlled 
thermostats. 

99. Chemical Economy Company, 1640 N. Spring St., Los Angeles, 
Calif. (Photographers' chemicals.) 

Research staff : C. W. Judd and 4 chemists. 

Research work: One-tenth time of 5 on celluloid and by-products 
and photographic chemicals. 



20 INDUSTRIAL RESEARCH LABORATORIES 

loo. Chemical Products Company, 44 K St., South Boston, Mass. 
(Manufacturing chemists.) 

Research staff : H. S. Mork, a chemists and i assistant. 

Research work : One-fifth time of 4 on cellulose chemistry, 
loz. Chemical Service Laboratories, Inc., The, W. Conshohocken, 
Pa. (Analytical, consulting and engineering chemists.) 

Research staff: J. Ed. Brewer and 4 assistants. 

Research work: One-fourth time of 5 on coal tar, coal tar distil- 
lates, fuels, gasworks ; raw materials and products. 

Equipment : For plant scale experiment, 
zos. Chicago Mill and Lumber Company, Conway Bldg., Chicago, 
111. 

Research staff: Don L. Quinn, 2 engineers in forest products, i 
mechanical engineer and i chemical engineer. 

Research work: Study of designs and mechanical properties of 
packing boxes, crates and methods of packing; also chemical studies 
on fibre board construction. 

Equipment : 16 ft. revolving drum testing machine which subjects 
packages to most of the hazards of transportation. 
Z03. Childs, Charles M., & Co., Inc., 41 Summit St., Brooklyn, N. Y. 
(Paints.) 

Research staff : F. D. Heim, 2 chemists and i assistant chemist. 

Research work : Full time of 4 on production of new color lakes. 

Equipment : Special equipment for producing color lakes and ma- 
chines for coating and polishing paper. 

Z04. Cleveland Testing Laboratory Co., The, 511 Superior Building, 
Cleveland, Ohio. 

Research staff : C. A. Black, 2 chemists and assistants as required. 

Research work: One-third time of 3 on problems in connection 
with industrial plants. 

Z05. Cochrane, H. S. B. W., Corporation, 17th St. and Allegheny 
Ave., Philadelphia, Pa., and Earnest, Pa. Formerly Harrison Safety 
Boiler Works. 

Research staff: P. S. Lyon and 5 engineers; J. D. Yoder and 2 
chemists. 

Research work : Full time of 6 on treatment of boiler feed water ; 
experiments on V-notch weirs and other flow meters; water soften- 
ing; problems in the development of traps, valves, steam and oil sepa- 
rators, etc. 

106. Coleman & Bell Company, The, Norwood, Ohio. Successors to 
National Stain and Reagent Co. (Biological stains and indicators.) 

Research staff: A. B. Coleman, W. H. Bell and i assistant. 

Research work : Approximately full time of 3 on syntheses of chem- 
ically pure organic dyestuffs and compounds for use in biology, path- 
ology, botany, and medicine in general; preparation and testing of 
all kinds of indicators for use in chemistry, biology, etc. ; preparation 
of chemically pure organic compounds and reagents and research upon 
practical industrial problems in organic chemistry. 

Equipment: Complete semi-commercial equipment for the prepa- 
ration of dyestuffs and facilities for testing chemicals and dyes for use 
as biological stains and indicators. 



INDUSTRIAL RESEARCH LABORATORIES 21 

107. Columbia Graphophone Manufacturing Company, Bridgeport, 
Conn. 

Research staff ; W. R. Palmer, general superintendent of engineer- 
ing. 

Research work: General development work in semi-plastics, ac- 
coustics, electroplating, material testing and specifications, machine 
developments, cabinet design and manufacturing methods. 

108. Commercial Testing and Engineering Co., 1785 Old Colony 
Bldg., Chicago, 111. (Coal analysis and boiler room economies.) 

Research staff : Jerome F. Kohout, 3 chemists and i engineer. 

Research work: Three-tenths time of 5 men on coal problems, — 
particularly coking low grade coal at high and low temperature ; mix- 
ing of coals to produce either high coke yield or large recovery of by- 
products or both. Examination of coal with special reference to 
proper time, temperature, and pressure conditions in coke oven. De- 
terioration of coal in storage with reference to its coking properties. 
Design of furnaces and boilers to meet special conditions of fuel or 
other requirements. 

109. Commonwealth Edison Company, 72 West Adams St., Chicago, 
111. (Operator of large electric light and power generating and dis- 
tributing systems.) 

Research staff : Louis A. Ferguson and 6 trained men. 

Research work: Part time of 7 on insulation deterioration, poten- 
tial rises due to switching operations, heat dissipation, electric fur- 
nace investigations and storage battery problems. 

Equipment : Primary and secondary standardizing instruments, 
especially for heavy currents ; oscillograph and high potential instru- 
ments; special generators and transformers; apparatus for dielectric 
and insulation tests. 

zzo. Condensite Company of America, Bloomfield, N. J. (Phenolic 
condensation products, chlorine substitution products, hydrochloric 
acid.) 

Research staflF: W. T. Hutchinson and i assistant. 

Research work: Three-fourths time of 2 on improvement of prod- 
ucts. 

zzi. Consolidated Gas Company of New York, 130 E. 15th St., New 
York, N. Y. Consolidated laboratories at Lawrence Point, Astoria, 
N. Y. 

Research staff : Charles A. Lunn, 5 chemists, 5 chemical engineers, 
15 assistant chemists and 6 laboratory assistants. 

Research work : Part time of staflF on problems consequent to the 
manufacture and distribution of illuminating gas (coal gas and car- 
buretted water gas). 

zza. Consolidated Gas Electric Light and Power Company of Balti- 
more, Lexington and Liberty Sts., Baltimore, Md. Laboratory at 
Spring Gardens Plant, Baltimore, Md. 

Research staflF: Minor C. K. Jones, 2 chemists and 5 laboratory 
assistants. 

Research work: One-tenth time of 8 on gas purification and gen- 
eral gas manufacture. 

Equipment: Complete experimental purifier equipment. 



22 INDUSTRIAL RESEARCH LABORATORIES 



1x3. Conwell, B. L*, ft Co., Inc., 2024 Arch St, Philadelphia, Pa. 
(Engineera, chemiats, inapcctors.) 

Reaearch staff: E. L. Conwell and 3-15 assistants. 

Research work : Variable amount of time on cement manufacture ; 
lime products manufacture; uses of cements, limes, etc; various in- 
dustries, involving calcination, grinding, etc., and recovery and util- 
ization of waste products. 

1x4. Cooper Hewitt Electric Company, 730 Grand St., Hoboken, N. 
J. (Lamps and rectifiers.) 

Research staff : R. D. Mailey and 2 assistants. 

Research work: Vapor electric apparatus and applications. 

Equipment : Facilities for fabricating clear fused quartz apparatus 
and methods for fusing (hermetic) clear quartz to all vitreous mate- 
rials, including metallic leads. 
1x5. Coming Glass Works, Coming, N. Y. (Technical glass.) 

Research staff: E. C. Sullivan, 3 chemists, 5 physicists and 4 en- 
gineers. 

Research work: Two-thirds time of 11 on physical properties of 
g:lass as related to chemical composition; lens design; furnace de- 
sign ; refractories ; manufacturing problems ; and new uses for glass. 

Equipment : Facilities for high temperature work. 
Z16. Com Products Refining Cknnpany, Edge water, N. J. 

Research staff : Christian E. G. Porst, 3 chemical engineers, 4 chem- 
ists and 13 helpers and laborers. 

Research work: Full time of 21 on problems confined to the in- 
dustry. 

Corona Chemical Co. See Pittsburgh Plate Glass Co. (p. 65). 
117. Cosden & Company, Tulsa, Okla. (Producers and refiners of 
petroleum.) 

Research staff : Charles K. Francis and about 50 chemists, physi- 
cists, engineers and assistants. 

Research work : One-third time of about 50 on petroleum and pe- 
troleum products, including gas. 

Equipment: General chemical and physical equipment for petro- 
leum work. 
iz8. Cosmos Chemical Co., Inc., 709 Berckman St., Plainfield, N. J. 

Research staff : Charles Blanc and 3 assistants. 

Research work : Organic synthetic compounds for commercial util- 
ization and factory problems. 

zi9-iao. Cramp, William & Sons Ship & Engine Building Co., The, 
Philadelphia, Pa. 

119. /. P. Morris Hydraulic Laboratory 

Research staff: F. H. Rogers, 2 engineers, 2 observers and i ma- 
chinist. 

Research work : Three-fourths time of 6 in the field of hydraulics 
and h}rdrodynamics. 

Ec[uipment: Hydraulic testing laboratory designed specially for 
testing models of hydraulic turbines, centrifugal pumps, spiral pumps, 
current meters, Pitot tubes, etc. Contains headrace flume, tailrace 
flume, motor driven pumps, tank for rating current meters and other 
necessary instruments. 



INDUSTRIAL RESEARCH LABORATORIES 23 

lao. Cramp Chemical Laboratory 

Research staff: N. H. Schwenk and i chemist 

Research work : Half-time of 2 on research work along metallurgi- 
cal lines. 
X9Z. Crane ft Co., Dalton, Mass. (Paper makers.) 

Research staff: C. Frank Sammet. 

Research work : Full time of i on development of new procedures, 
novelties and mill problems. 

Equipment: Well equipped for research relative to paper manu- 
facture. 

X99. Crane Co. (Metallurgical Department), South Avenue, Bridge- 
port, Conn., and 836 South Michigan Ave., Chicago, 111. (Valves, 
pipes, fittings and other supplies from iron, steel, brass and bronze, 
for water, gas, and steam work.) 

122a. Bndgeport laboratory 

Research staff : Allen P. Ford, 2 metallurgists, i chemist, 3 assist- 
ant chemists and 2 helpers. 

Research work : Small part time of 9 on problems connected with 
the industry. 

Equipment: Entirely equipped for routine metallurgical work. 
100,000-pound tensile testing machine; transverse, torsion and hard- 
ness testing machines. 

122b. Chicago laboratory 

Research staff: L. W. Spring, i assistant and 12 men, 2 of whom 
are doing physical and metalloppraphic testing. 

Research work : One-tenth time of 14 on problems connected with 
the industry. 
193. Crompton ft Knowles Loom Works, Worcester, Mass. 

Researjch staff: V. E. Hillman, 2 metallurgists, i chemist, i libra- 
rian and 2 non-technical assistants. 

Research work : Full time of 7 on heat treatment of steel ; case car- 
burizing and cyanide hardening ; quenching mediums ; core oils ; mold- 
ing sands; molding methods; blow holes and shrinkage cavities in 
cast iron ; illumination ; copper plating metal parts ; and work on non- 
ferrous alloys — ^aluminum, brass, bronze and bearing metals. 
Z94. Crucible Steel Company of America, Pittsburgh, Pa. 

Research staff: Charles Morris Johnson and 39 chemists and 
physicists. 

Research work: Chemical department, one-fifth time of 8 men. 
Physical division, four-fifths time of 3 men. 

Equipment : i Olsen 100,000-pound tensile testing machine, i Olsen 
impact machine, i Olsen torsion machine, i Olsen new ductility ma- 
chine for testing the ductility of plates up to one-fourth inch thick, 
2 Pittsburgh Instrument Company Brinell- testing machines, 2 Shore 
scleroscopes, i O-Z cutmeter tachometer, i Brown instrument (criti- 
cal point machine), Leitz microphotographic outfit and i Olsen ex- 
tensometer. 

Z95. Cudahy Packing Co., The, South Side Station, Omaha, Nebr. 
(Meat packers, etc.) General and research laboratory, Omaha, Nebr. 
Laboratories also in Chicago, III., and Kansas City, Kans. 



24 INDUSTRIAL RESEARCH LABORATORIES 

Research staff: Millard Langfeld, superintendent of laboratories, 
5 chemists and 2 workers. 

Research work: Gland products, oils and greases, glues, curing 
meats, etc. 

126. Cumberland Mills, Cumberland Mills, Me. S. D. Warren Co., 
Boston, Mass., proprietors. (Pulp and paper.) 

Research staff: E. Sutermeister, 2 to 4 chemists and 2 or 3 as- 
sistants. 

Research work : One-third time of 6 on problems relating to pulp 
and paper industry. Tests of various woods and fibrous materials; 
studies on soda and sulphite pulp processes and on solubility, adhe- 
sive strength and viscosities of caseins and their solutions and coating 
mixtures; studies of black ash waste and its possible utilization; 
studies of rate of absorption of moisture by paper; investigations of 
the storage conditions for pulp wood ; studies on the frothing of coat- 
ing mixtures ; tests of new sizing agents and further studies on rosin 
sizing. Bleaching studies on sulphite and soda fiber to show effects 
of variable factors ; further applications of a beating test to show rela- 
tive strength of fibers ; investigations relating to manufacture of satin 
white; studies of defects in papers and of means to overcome them. 

Equipment : Apparatus for the manufacture of paper on laboratory 
scale ; complete testing apparatus. Available in mill ; 400-pound ver- 
tical soda digester; 350-pound beater, and small Fourdrinier paper 
machine. Apparatus to study foaming of coating mixtures. 

127. Curtiss Aeroplane & Motor Corporation, Garden City, L. I., 
N. Y. 

Research staff : H. T. Booth, 2 engineers, i mechanic and i model 
maker. 

Research work : One-half time of 4 on wind tunnel tests of wing^, 
bodies, propellers, etc. Load tests of complete airplanes, perform- 
ance tests of complete airplanes and miscellaneous investigations 
along different aeronautical lines. 

Equipment : One four-foot wind tunnel in which wind velocities of 
75 m. p. h. are obtained. One seven-foot wind tunnel in which wind 
velocities of 100 m. p. h. are reached. 

Curtiss Engineering Corporation, The. See Curtiss Aeroplane & 
Motor Corporation. 

128. Cutler-Hammer Mfg. Co., The, Milwaukee, Wis. (Electric con- 
trolling devices.) 

Research staff: Arthur Simon, i physicist, i glassblower and me- 
chanical helpers as needed. Has help of Experimental Department 
with its staff of developing engineers and mechanics. 

Research work: Full time of 2 in connection with electrical dis- 
charge in gas, particularly evacuated tubes and bearing on control of 
electric currents. 

129. Davis-Boumonville Company, Jersey City, N. J. (Welding and 
cutting apparatus.) 

Research staff: Frank J. Napolitan and i assistant. 

Research work: Large part time of 2 on metallography of oxy- 
acetylene welding, design of new apparatus and development of scope 
of process. 



INDUSTRIAL RESEARCH LABORATORIES 25 

Equipment: Gas laboratory equipped for measuring flow of gas 
under high pressures; micro-manometers for measurement of high 
pressures. 

130. Davis Chemical Products, Inc., Springfield, N. J. 
Research staff: E. J. Fry, i engineer and i chemist. 

Research work: One-half time of 3 on cellulose esters, nitrocellu- 
lose, nitrocellulose solvents and solutions, artificial and imitation 
leather, coatings, lacquers and films ; explosives, commercial and mili- 
tary. 

Equipment : Apparatus for testing the physical and chemical prop- 
erties of films and coatings based on cellulose esters, including viscos- 
ity, stability, aging, accelerated life tests and strength; facilities for 
large scale experiments and demonstrations. 

131. Davison Chemical Company, The, Baltimore, Md. (Sulphuric 
acid.) 

Research staff: A. E. Marshall and trained research men as re- 
quired. 

Research work : Full time of staff on improvement of manufactur- 
ing processes for sulphuric acid and utilization of waste materials. 

Equipment: Semi-commercial equipment for development of proc- 
esses evolved in laboratory. 

Dayton Engineering Laboratories Company. See General 
Motors Research Corporation (p. 35). 

133. Dean Laboratories, Inc., ^th St. and Walton Ave., Philadelphia, 
Pa. 

Research staff: J. Atlee Dean, 3 chemists, 3 bacteriologists and i 
technician and clerical helper. 

Research work : One-half time of 8 on physiological, pharmaceuti- 
cal and clinical chemistry; hypodermic preparations, especially the 
endocrine glands ; laboratory reagents such as colloidal gold and mi- 
croscopic stains. 

Equipment : Facilities for rapid and accurate examinations of body 
fluids. 

133. Dearborn Chemical Company, McCormick Building, Chicago, 
111. (Scientific boiler feed water treatment.) Laboratories at 1029 
W. 35th St., Chicago, 111. 

Research staff : D. K. French, 5 chemists and 5 assistants. 

Research work : Small part time of 1 1 on scientific boiler feed water 
treatment and chemical control of corrosion. 

Equipment: Hess-Ives tintometer and Thurston friction machine; 
all types of viscosimeters. 

134. Dehls & Stein, 237 South St., Newark, N. J. (Manufacturing 
chemists.) 

Research staff : L. Stein and i chemist. 

Research work: One-half time of 2 along lines of fermentology, 
synthetic essential oils, caramel. 

135. Deister Concentrator Company, The, 611 High St., Ft. Wayne, 
Ind. (Concentrating tables for every purpose.) 

Research staff : Regular force consists of i metallurgical engineer, 
together with occasional assistance in advisory capacity from other 
members of the company. 



26 INDUSTRIAL RESEARCH LABORATORIES 

Research work : On gravity or table concentration of various ores 
sent us for this purpose from all parts of the world; extensive work 
in the washing of the finer sizes of coal (both anthracite and bitumi- 
nous) below Uiat usually handled on jigs, etc. This work is done in 
both small lots and in carload quantities. 

Equipment: One i6 by i8-inch Pennsylvania roll crusher, I pair 
lo-inch corrugated rolls, i pair 5>^-inch smooth rolls for regrinding, 
I Mitchell vibrating screen, i No. 7 Deister-Overstrom diagonal dedc 
coal-washing table, i No. 6 Deister-Overstrom diagonal deck table for 
ore treatment, i No. 14 Deister-Overstrom diagonal deck, jr., table, 
I 12-foot Dorr thickener, i size 4-1 American vacuum filter, i Inger- 
soll-Rand vacuum pump. 

136. DeLaval Separator Co.» That 165 Broadway, New York, N. Y. 
(Centrifugal machinery.) 

Research staff: A. F. Meston and i assistant. 

Research work : Full time of 2 on purifying used oils, clarification 
and separation of commercial products, making of emulsions, clari- 
fication of extracts, purifying of crude and fuel oils, application of 
centrifugal machines to industrial processes, etc. 

Equipment : Centrifugal apparatus of all classes. 

137. Dennis, Martin, Company, The, 859 Summer Avenue, Newark, 
N. J. {Chrome tannage.) 

Research staff : Harold Dennis, i chemical engineer and 2 chemists. 
Research work: Three-fourths time of 4 on tanning and tanning 
materials. 

138. Detroit Edison Company, The, Detroit, Mich. (^Operating elec- 
tric light and power generating stations and distributin|^ systems; 
central heating stations and distributing systems and illummating gas 
plants and distributing systems.) 

Research staff : C. r . Hirshfield, i engineer, 2 to 8 trained men, and 
4 or more assistants. 

Research work: Problems in better generation, distribution and 
utilization of electricity, steam for heating and artificial gas. 

139. Detroit Testing Laboratory, The, 3726 Woodward Ave., Detroit, 
Mich. (Analytical consulting and research chemists.) 

Research staff : W. P. Putnam, 6 chemists, i bacteriologist, i chem- 
ical engineer and i electrical and mechanical engineer, i pharmaceuti- 
cal engineer, i foundry engineer, i steam engineer and i automobile 
engineer. 

Research work : Full time of i chemist and 2 engineers on special 
problems in shale oil development, fertilizer manufacture, metallurgi- 
cal problems, heat treatment of metals, fuel problems, water purifica- 
tion and ore dressing. 

Equipment: 100,000-pound Reihle testing machine, 10,000-pound 
Olsen testing machine, Weston precision laboratory type instruments, 
shunts and multipliers for instrument calibration and precision test- 
ing, Leeds and Northrup precision type potentiometer and large ca- 
pacity storage batteries. 

140. Dewey & Akny Chemical Companyt Harvey St., Cambridge, 
Mass. 



INDUSTRIAL RESEARCH LABORATORIES 27 

Research staff: Bradley Dewey, i chemical engineer and 2 chem- 
ists. 

Research work : One-half time of 4 on adhesives, fluxes, and seal- 
ing compomids. 

141. Dartre Products, Inc., 25 Illinois St., Buffalo, N. Y. (Soluble 
starch and dextrin products.) 

Research staff: A. D. Fuller and 2 assistants. 

Research work : One-fourth time of 3 on hydrolysis of starch, tor- 
rification of starch, colloids as related to adhesives and dextrin. 
243. Diamond Chain ft Manufacturing Company, 502 Kentucky Ave., 
Indianapolis, Ind. (Steel roller and block chains, sprockets, etc.) 

Research staff: H. B. Northrup, i chief metallurgist and i assistant 
metallurgist. 

Research work: Approximately one-half time of 3 on carburizing 
compounds and carburizing, hardening and drawing of alloy vs. plain 
carbon steels for chain parts. 

143. Diamond Match Co., The, Oswego, N. Y. 

Research staff : Frederick VanDyke Cruser, 7 chemists and chemi- 
cal engineers, i mechanical en^neer and 3 assistants. 

Research work: One-half time of 12 on problems connected with 
match manufacture and its allied branches. 

144. Dicks David Company, Incorporated, Varick and N. Moore Sts., 
New York, N. Y. (Dyestuffs and chemicals.) Laboratory at 22d 
St. and Stewart Ave., Chicago Heights, 111. 

Research staff: H. Philipp, P. H. Condit, W. G. Brunjes, 8 chem- 
ists and 4 engineers. 

Research work: Small part time of 15 chiefly on triphenylmethane 
dyestuffs. 
Z45. Digestive Ferments Co., Detroit, Mich. 

Research staff : Howard T. Graber, director of the chemical labora- 
tory; Henry G. Dunham, director of the bacteriological laboratory, 
and assistants. 

Research work: Two-thirds time of assistants devoted to physio- 
logical and proteid chemistry and commercial classification of bac- 
teriology. 

Equipment: Apparatus for the electrometric estimation of hydro- 
gen ion concentration. Vitreosil mufile furnace with thermocouple 
and Brown recording pyrometer for the accurate estimation of ash at 
definite temperatures. Experimental laboratory vacuum drier, ther- 
mocouple and recording thermometer for moisture determinations. 
Schmidt and Haensch saccharimeter with bichromate cell. 

146. Dill ft Collins Co., Richmond and Tioga Sts., Philadelphia, Pa. 
(Paper makers.) 

Research staff: Frank H. Mitchell, 2 chemists, 2 chemical engi- 
neers and 3 assistants. 

Research work : One-half time of i chemist to full time of 2 chem- 
ists on problems of the paper industry. 

147. Dodge Brothers, Detroit, Mich. (Automobiles and accessories.) 
Research staff: F. E. McCleary, 17 chemists, 25 engineers, physical 

testers and trouble men. 
Research work : Approximately one-tenth time of staff on automo- 



28 INDUSTRIAL RESEARCH LABORATORIES 

bile materials, treatment, application, etc. This covers cast iron, steel, 
brass and bronze, babbitt, aluminum, wood, rubber, etc.; lubrication, 
paints and varnishes, baking japans and fuel. 

148-150. Doehler Die-Casting Co., Court, Ninth and Huntington Sts., 
Brooklyn, N. Y. Laboratories also at Smead and Prospect Aves., To- 
ledo, Ohio, and at Chicago, 111. 

148. Brooklyn Laboratory 

Research staff: Charles Pack, 5 chemists, 6 junior chemists, i fuel 
engineer, i steel metallurgist. 

Research work: One-fifth time of 14 on problems pertaining di- 
rectly or indirectly to casting of metals, particularly non-ferrous 
metals. 

149. Toledo Laboratory 

Research staff: Charles Pack, i metallurgist, i chemist and 5 junior 
chemists. 

Research work : One-fifth time of 8 on problems pertaining to cast- 
ing of metals. 

150. Chicago Laboratory , 

Research staff: J. C. Fox and 2 chemists. 

Research work: One-tenth time of 3 on non-ferrous alloys. 
151. Doherty Research Company, Empire Division, Bartlesville, 
Okla. 

Research staff: J. P. Fisher, i superintendent and 10 engineers. 

Research work : Full time of 12 on research problems dealing with 
production, transportation and refining of petroleum; transportation 
and distribution of natural gas ; conservation of fuel. 
15a. Dorite Manufacturing Company, The, 116 Utah St., San Fran- 
cisco, Calif. (Stucco, flooring, magnesite.) 

Research staff: E. H. Faile and i assistant. 

Research work: One-half time of 2 on investigation of the best 
methods for the manufacture of various magnesite products, including 
stucco and flooring and particularly of the most practical methods in 
their application and use. 

153. Dorr Companv, The, loi Park Ave., New York, N. Y. (Engi- 
neers.) Testing plant and laboratory at Westport Mill, Westport, 
Conn. 

Research staff : H. A. Linch, i analytical chemist, i chemical engi- 
neer, I sanitary engineer, i mechanical engineer, 4 assistants. Chemi- 
cal, metallurgical, sanitary and mechanical engineers from the New 
York ofHce are available for advice and work as needed. 

Research work: Major problems in connection with the produc- 
tion of water-floated materials for pigments, fillers, etc. Concentra- 
tion and sulphating. Roasting of ores. Washing and classification 
of abrasives. Studies dealing with the development of mechanical set- 
tling and dewatering, classification, continuous agitation and counter- 
current washing. Trade waste and sewage treatments. 

Equipment: Bins, crushers, grinding mills, classifiers and washers 
of various types, thickeners, filterers, concentrating tables, flotation 
machines, mechanical multiple-hearth furnace, electric roasting fur- 
nace, etc. Plant fully equipped to work out hydrometallurgical and 
wet chemical and industrial problems. 



INDUSTRIAL RESEARCH LABORATORIES 29 

154. Drackett» P. W., & Sons Co., The, Cincinnati, Ohio. (Manu- 
factures heavy chemicals; distributes Solvay Process Co. alkalis and 
other heavy chemicals.) 

Research stafiF: K. S. Kersey and i assistant. 

Research work : Development of products and their uses. 

155. Dunham, H. V., 50 E. 41st St., New York, N. Y. 
Research staff : H. V. Dunham with from 2 to 6 assistants. 
Research work : Full time of staff on food products, oils, including 

mineral oils and especially developments and improvements in the 
making and use of milk casein and milk products. 

Equipment: Mixing machines, dryers and other semi-industrial 
equipment. 

156-160. du Pont, E. I., de Nemours & Company, Wilmington, Del. 
Chemical Department operates 5 research laboratories in addition to 
organization at its main office. (Information concerning the entire 
department is followed by separate accounts of the 5 laboratories.) 

Research staff: Charles L. Reese, 200 graduate chemists and en- 
gineers, 122 other salaried employees and 200 payroll employees. 

Research work: Practically full time of 522 on manufacturing 
operations of the du Pont Company, including miscellaneous chem- 
icals, dyes and intemediates, explosives, artificial leather, rubber goods, 
plastics, pyroxylin solutions, lacquers, paint and varnish, including 
the production of miscellaneous raw materials as mineral acids and 
nitrate of soda. 

156. Pyralin Laboratory, Arlington, N. /. 

Research staff : E. A. Wilson, 22 graduate chemists and engineers, 
13 other salaried employees and 24 payroll employees. 

Research work: Practically full time of 59 on pyralin, pyroxylin 
solutions, and raw materials therefor. 

Equipment: Fairly complete line of semi-manufacturing scale 
equipment for the experimental manufacture of paper, nitrocellulose 
and pyralin. 

157. Eastern Laboratory, Box 424, Chester, Pa, 

Research staff: C. A. Woodbury, 23 graduate chemists and en- 
gineers, 13 other salaried employees and 33 payroll employees. 

Research work : Practically full time of 69 on high explosives and raw 
materials therefor, processes of manufacture, and methods of testing. 

Equipment: Very complete facilities for testing properties of ex- 
plosives. 

158. Experimental Station, Henry Clay, Del. 

Research staff : A. P. Tanberg, 28 graduate chemists and engineers, 
30 other salaried employees and 63 payroll employees. 

Research work: Practically full time of 121 on smokeless powder, 
black powder, nitrocellulose, heavy chemicals, paint and varnish, and 
raw materials therefor. Also miscellaneous organic, inorganic, and 
biochemical research. 

Equipment: For experimental manufacture of propellant powders, 
constant temperature magazines for stability tests, and storage of 
smokeless powder, experimental equipment for the manufacture of 
coated fabrics, ranges for testing small arms powders for velocity, 
pressure and accuracy. 



30 INDUSTRIAL RESEARCH LABORATORIES 

1 59. Jackson Laboratory, Box $25, Wilmington, Del. 

Research staff: Fletcher B. Holmes, 80 graduate chemists and 
ennneers, a8 other salaried employees and 71 payroll employees. 

Research work: Practically full time of 179 on dyes and inter- 
mediates. 

Equipment: Extensive equipment for semi-works operation and 
investigation of a variety of chemical processes. 

160. Redpath Laboratory, Parlin, N. J. 

Research staff: E. B. 6enger» 14 graduate chemists and engineers, 
8 other salaried em]>loyees and 7 payroll employees. 

Research work : Practically full time of 29 on film work. 

Equipment: Small scale apparatus for coating films, and equip- 
ment for physical and chemical testing of film and photo-chemist^. 
z6i. Durfee, Winthrop C, 516 Atlantic Ave., Boston, Mass. (Con- 
sulting and manufacturing chemist.) 

Research staff : Winthrop C. Durfee, 5 chemists, i physicist and 3 
assistants. 

Research work: One-half time of 10 on application of dyes and 
chromium compounds in wool dyeing; chrome tanning. 
z69. Duriron Company, Inc., The, N. Findlay St., Dayton, Ohio. 
(Acid-proof alloy castings.) 

Research staff : P. D. Schenck, i metallurgist, i chemist, i assistant 
chemist, i engineer and i laboratory assistant 

Research work: One-fourth time of 6 on chemical corrosion of 
metals, metallurgical problems, physical properties, etc.; problems 
relating to the handling of corrosives. 

Equipment: Experimental foundry. 
263. Dye Products & Chemical Company, Inc., aoo 5th Ave., New 
York, N. Y. 

Research staff : C. K. Simon, i chemist and 2 assistants. 

Research work : Full time of i chemist and part time of 2 assistants 
on problems connected with the manufacture of dyes and intermedi- 
ates and the improvement of present processes. 

164. Eagle-Picher Lead Company, The, 208 S. LaSalle St., Chicago, 
111. (Manufacturers, miners and smelters of lead products.) Labora- 
tory at Joplin, Mo. 

Research staff: J. H. Calbeck and 4 chemists. 

Research work : Full time of 5 on physical and chemical properties 
of paints and white pigments ; storage battery oxides and chemical and 
metallurgical problems pertaining to the manufacture and uses of the 
oxides of lead and zinc. 

Equipment : Pfund's colorimeter, spectrometer, photometer, micro- 
photographic equipment. 

165. Eastern Finishing Works, Inc., Kenyon, R. I. 
Research staff: William H. Adams and 2 assistants. 

Research work : Part time of 3 on test valuation and general study 
of waterproofing, dyeing, sizing and mildew resistance in connection 
with finishing cotton goods. 

166. Eastern Malleable Iron Company, Naugatuck, Conn. (Cast- 
ings.) 



INDUSTRIAL RESEARCH LABORATORIES 31 

Research staff: W. R. Bean and 6 assistants. 

Research work: Full time of 3 and one-half time of 4 on metal- 
lurgical research as applied to composition, annealing and production 
of malleable iron. 

Equipment: Special laboratory muffle annealing furnace, elec- 
trically heated, with automatic electric temperature control bath for 
maintaining indefinitely temperatures up to 2000^ F. and also con- 
trolling rate of heating and cooling at several rates between 4^ F. per 
hour and 20** F. per hour. 
Z67. Ea3tem Manufacturing Company, Bangor, Me. (Paper.) 

Research staff : H. H. Hanson, 5 chemical engineers, 2 chemists, 3 
routine chemists, i electrical engineer and i assistant. 

Research work: Full time of 14 on standardization of processes, 
increasing production, development of by-products and development 
of improved processes. 

Equipment: Small paper beater, apparatus for determining slow- 
ness of beater stock, strength of stock in beaters and on finished-paper. 
z68. Eastman Kodak Company, Rochester, N. Y. 

Research staff: C. E. K. Mees, 45 chemists, physicists and photo- 
graphic experts and 60 assistants. 

Research work: Full time of 105 on theory of photography, de- 
velopment of new photographic materials and methods, and the study 
of the theory of manufacturing processes, and the production of syn- 
thetic organic chemicals. 

Equipment : Sensitometric and lens testing apparatus, physical and 
colloidal chemical apparatus for use in the study of photographic 
theory. 

169. Eavenson ft Levering Co., 3rd and Jackson Sts., Camden, N. J. 
(Wool scouring and carbonizing.) 

Research staff: Chas. E. Mullin, 2 or 3 chemists and assistants. 

Research work: Approximately one-half time of staff on textiles, 
wool particularly ; wool scouring, carbonizing and dyeing ; utilization 
of wool waste and refuse such as scouring liquors ; wool grease and 
detergents. 

170. Edison, Thomas A., Laboratory, Orange, N. J. 

Research staff: Thos. A. Edison and about 250 machinists, chem- 
ists, physicists, experimenters, designers and draughtsmen. 

Research work : Nearly full time of 250 on almost every branch of 
scientific research. 

Equipment: Large scrap heap from which to rob to build other 
apparatus, and accumulations of every kind of material and chemical 
so as not to wait. 

171. Eimer ft Amend, Third Ave., i8th to 19th St., New York, N. Y. 
(Industrial and educational laboratory apparatus, assayers' materials, 
chemicals and drugs.) 

Research staff: O. P. Amend, C. G. Amend, 2 chemists, 4 expert 
glass blowers and i mechanic. 

Research work : Organic chemicals and special glass and metal ap- 
paratus for scientific investigations. 

Z72. Electrical Testing Laboratories, 80th St. and East End Ave., 
New York, N. Y. 



32 INDUSTRIAL RESEARCH LABORATORIES 

Research staff : Clayton H. Sharp, i chief engineer and 7 research 
men. 

Research work : One-tenth time of 9 on dielectric losses ; thermal 
conductivity of heat insulators at high and low temperatures; radia- 
tion efficiency of gas heaters; special cases of electrolysis by stray 
currents ; breakdown voltage of sheet insulation. 

Equipment: Very complete for electrical standardizing and re- 
search, photometry, mechanical measurements, fuel testing, paper 
and textile testing, thermometer and pyrometer standardization. 

173. Electro Chemical Company, The, Dayton, Ohio. (Electrolytic 
cells for producing sodium hypochlorite.) 

Research staff: John Gerstle and i chemical engineer. 

Research work : Two-thirds time of 2 in connection with producing 
sodium hypochlorite from a sodium chloride solution, principally in- 
creasing efficiency of electrolytic cells. 

174. Electrolabs Company, The, 2635 Penn Ave., Pittsburgh, Pa. 
(Electrolytic gas specialists.) 

Research staff: I. H. Levin, i chemist, i engineer and i physicist. 
Research work : Full time of 4 on electrolytic dissociation of water, 
application of hydrogen to vegetable oil refinement, etc. 

Electro Metallurgical Company. See Union Carbide and Car- 
bon Research Laboratories, Inc. (p. 78). 

Ellis, Carleton, Laboratories. See Ellis-Foster Company. 

175. Ellis-Foster Company, 92 Greenwood Ave., Montclair, N. J. 
(Chemical products and processes.) 

Research staff : Carleton Ellis and a variable number of assistants. 
Research work : Approximately full time of staff on organic chem- 
istry and ceramics. 

176. Emerson Laboratory, 145 Chestnut St., Springfield, Mass. 
Research staff: H. C. Emerson and 5 chemists. 

Research work: One-fourth time of 6 on paper and textile prob- 
lems. 

Empire Gasoline Co. See Doherty Research Company, Empire 
Division (p. 28). 

Empire Tannery. See Gallun, A. F., & Sons Co. (p. 34). 

177. Eppley Laboratory, The, 12 Sheffield Ave., Newport, R. L 
(Physical-chemical laboratory.) 

Research staff : Warren C. Vosburgh, 2 chemists and i instrument 
maker. 

Research work: One-half time of 4 on cadmium standard cells, 
physico-chemical apparatus, standards of electromotive force, spec- 
troscopy, theory of solutions from electrical standpoint and thermo- 
couples for precise measurements. 

Equipment : Spectroscopes and potentiometers. 

178. Eustis, F. A., 131 State St., Boston, Mass. (Metallurgical en- 
gineer.) 

Research staff: F. A. Eustis. 

Research work: Part time of i on metallurgical problems con- 
nected with copper, sulfur and iron and the purification of smelter 
smoke. 

179. Factory Mutual Laboratories under the supervision of Asso- 



INDUSTRIAL RESEARCH LABORATORIES 33 

ciated Factory Mutual Fire Insurance Companies, Inspection Depart- 
ment, 31 Milk St., Boston, Mass. 

Research staff: C. W. Mowry, 2 chemists and 8 engineers. 

Research work: One-sixth to one-fourth time of 11 on fire-protec- 
tion engineering problems. 

Equipment: Apparatus for chemical, hydraulic and mechanical 
tests and investigations of fire-protection devices. 
i8o. Fahy» Proc^ P., 50 Church St., New York, N. Y. 

Research staff: Frank P. Fahy. 

Research work: Full time of i on magnetic-mechanical analysis of 
iron and steel products. 

Equipment : Special magnetic testing devices. 
i8i. Falls Rubber Company, The, Cuyahoga Falls, Ohio. 

Research staff : G. D. Kratz, 4 chemists and 2 eng^ineers. 

Research work : One-half time of 5 and one-fourth time of 2 on the 
investigation of raw rubbers and the process of vulcanization; new 
machines and mechanical methods. 

Equipment : For the study of problems in the vulcanization of rub- 
ber. 

i8a. Fansteel Products Company, Inc., North Chicago, 111. (Elec- 
trical, steel and chemical products.) 

Research staff: Clarence W. Balke, 2 chemists, i engineer, and i 
assistant. 

Research work: One-half time of 5 on rare metals, tungsten, 
molybdenum, cerium, tantalum and columbium. 

183. Feculose Co. of America, Ayer, Mass. (Pastes, adhesives, size, 
etc.) 

Research staff: John T. Gibbons and 3 chemists. 

Research work : Full time of 4 on starches and starch products. 

184. Federal Phosphorus Company, Anniston, Ala. 
Research staff: J. N. Carothers and 3 chemists. 

Research work : Full time of 2 men on plant process for production 
of phosphoric acid by electric smelting of phosphate rock ; production 
of phosphoric acid salts. 

185. Federal Products Company, The, 7818 Lockland Ave., Cincin- 
nati, Ohio. (Cologne spirits and denatured alcohol.) 

Research staff: J. F. Kraeger and i assistant chemist. 

Research wotk : One-half time of 2 on production of ethyl alcohol 
from materials containing fermentable substances and recovery of 
valuable by-products from distillery waste. 
x86. Firestone Tire & Rubber Company, Akron, Ohio. 

Research staff: E. W. Oldham, director of general laboratory; N. 
A. Shepard, director of organic research ; E. C. Zimmerman, director 
of physical chemical research and 20 chemists and engineers; J. E. 
Hale, director of development department, and 12 engineers. 

Research work : Full time of o on study of vulcanization, physical 
and chemical properties of vulcanized rubber in conjunction with 
various accelerators and compounding materials, and problems aris- 
ing in connection with the manufacture of rubber products. 
187. FitzGerald Laboratories, Inc., The, Niagara Falls, N. Y. 

Research staff: F. A. J. FitzGerald and 3 assistants. 



34 INDUSTRIAL RESEARCH LABORATORIES 

Research work: One-half time of 4 on electric furnaces, refrac- 
tories and electrometallurgy. 

Equipment: For electro-thermal laboratory. 
z88. Florida Wood Products Co., Jacksonville, Fla. (Phosgene gas.) 

Research staff: E. B. Smith and i chemist 

Research work : Part time of 2 on development of products of phos- 
gene gas; pharmaceuticals derived from wood products. 

Equipment: Special facilities for handling destructive distillation 
problems, being equipped with iron retorts capacity of 50 pounds to 
1500 cubic feet. 

289. Fort Worth Laboratories, Box 1008, Fort Worth, Texas. (Con- 
sulting, analytical chemists and chemical engineers.) 

Research staff: F. B. Porter, R. H. Fash, and assistants, 6 chem- 
ists and about 8 helpers. 

Research work: Small part time on industrial problems as pre- 
sented, cotton oil refining and boiler water problems. 

190. Foster-Heaton Company, 27 Badger Ave., Newark, N. J. 
Research staff : Edward W. Rhael, i chemist and i engineer. 
Research work : Approximately one-third time of 3 on development 

of coal tar dyestuffs soluble in oils, fats and waxes. 

191. Frees, H. E., Co., The, 2528 W. 48th Place, Chicago, 111. (Brew- 
ers and distillers laboratory.) 

Research staff: Herman E. Frees, i chemist and i fermentologist. 
Research work : Approximately one-half time of 3 on foods, yeasts, 
fermentation and beverages. 

292. Fry, H. C, Glass Company, and Beaver Valley Glass Co., 
Rochester, Pa. 

Research staff : R. F. Brenner and 2 assistants. 

Research work : More than one-half time of 3 on new varieties and 
compositions of glass. This work is carried out first in small crucible 
meltings and then in regular factory pots. 

Equipment: High-temperature gas-fired furnace. 

293. Gallun, A. F., & Sons Co., Milwaukee, Wis. (Proprietor, Em- 
pire Tannery.) 

Research staff: John Arthur Wilson and 7 chemists. 

Research work: Approximately four-fifths time of 8 on experi- 
mental tanning, pure and applied colloid chemistry, physical chemis- 
try, photomicrography, ultramicroscopy, histology of skin, and special 
applications of concentration cells. 

Equipment: Experimental tannery. 
194. Garfield Aniline Works, Inc., Box 196, Passaic, N. J. Labora- 
tory at Garfield, N. J. 

Research staff : Arthur F. F. Mothwurf and 6 chemists. 

Research work : Full time of 6 on coal tar intermediates, coal tar 
dyes (azo-colors and triphenylmethane derivatives) and sample dye- 
ing. 

295. General Bakelite Company, Perth Amboy, N. J. Supplementary 
laboratory in Yonkers, N. Y. 

Research staff : L. H. Baekeland, 2 engineers and 5 chemists. 

Research work: Full time of 8, confined almost exclusively to 



INDUSTRIAL RESEARCH LABORATORIES 35 

phenol-formaldehyde condensation products, both development and 
commercial applications. 

Equipment: In form of electric ovens, stills, vulcanizers, pebble 
mills and rubber machinery. 

196. General Chemical Company, Research Department, 25 Broad 
St., New York, N. Y. 

Research staff : G. P. Adamson and approximately 45 chemists. 

Research work : Full time of 46 on improving existing processes of 
the company, and devising new processes. 

General Chemical Company has recently become a part of the Allied 
Dye & Chemical Corporation and reorganization of its research de- 
partment is now in progress. 

297. General Electric Company, Schenectady, N. Y. Laboratories 
also at Lynn and Pittsfield, Mass., Harrison, N. J. and Cleveland, 
Ohio. 

Research staff: Willis R. Whitney, 2 assistant directors, 50 chem- 
ists, 12 physicists, 13 engineers, 50 research assistants, and machinists, 
glass-blowers, electricians and clerks. 

Research work: Full time of staff devising new forms of electric 
lights and improving existing forms. Development of Coolidge X-ray 
tube. Invention of new and development of existing forms of electric 
equipment and apparatus. Study of metals and alloys for electrical 
uses. Wireless transmission development. Study of insulation. 
Many fundamental physical and chemical scientific researches also 
are carried on. 

See National Lamp Works of General Electric Company (p. 56). 
198. General Engineering Company, Incorporated, The, 159 Pier- 
pont St., Salt Lake City, Utah. (Consulting engineers, ore testing.) 

Research staff: J. M. Callow, i chemist, 2 metallurgical engineers 
and 2 helpers. 

Research work: Full time of 6 on metallurgical and engineering 
problems, specializing on ore treatment problems. 
X99. General Motors Research Corporation, Box 745, Moraine City, 
Dayton, Ohio. 

Research staff: C. F. Kettering, president and active directing 
engineer, F. O. Clements, director of research, and 251 employees, 
divided into specialized groups or departments, made up of chemists, 
metallurgists, electrical engineers, mechanical and other research 
engineers, assistants and helpers. (Control division made up of 147 
additional employees and manufacturing division, having at the pres- 
ent time 18 members, bring the total number of employees up to. 416.) 

Research work: Full time of staff on strictly automotive research 
of interest to General Motors Corporation. 

Equipment : Laboratories capable of conversion, upon short notice, 
into mechanical, chemical or electrical laboratories. Complete shop, 
foundry and heat treat departments. 
200. General Tire & Rubber Co., Akron, Ohio. 

Research staff: H. B. Pushee and 2 men. 

Research work : One-tenth time of 3 on development of better rub* 
ber compounds ; rubber accelerators ; coefficient of vulcanization. 
20X. Gibbs Preserving Company, 2303 Boston St., Baltimore, Md. 



36 INDUSTRIAL RESEARCH LABORATORIES 

Research staff : David R. Dotterer and i assistant. 

Research work : Canned goods and jellies. 
3oa. Gillette Safety Razor Co.. 47 W. ist St., Boston, Mass. 

Research staff : Henry E. K. Ruppel, 4 chemists, i special engineer 
and technicians. 

Research\ work : Part time of 6 or more on development and im- 
provement of analytical methods; precision measurements; heat 
treatment of steel: (a) metallographic investigations, (b) practical 
applications; electro-deposition of metals; abrasives; study of edges 
with special reference to shaving. 

303. Glass Container Association of America, 3344 Michigan Ave., 
Chicago, 111. 

Research staff : A. W. Bitting and 4 assistants. 

Research work: Full time of 5 on standardization of glass con- 
tainers, improved methods of packing glassware for shipment, foods 
and beverages in glass and improvement in containers and closures. 

Equipment : Complete equipment for the preparation and packing 
of foods in glass and testing bottles, jars and packing materials. 
203a. Glidden Company, The, Cleveland, Ohio. (Paints, varnishes, 
enamels, stains, dry colors, insecticides, vegetable oils.) 

Research staff: F. M. Beegle, chief chemist, 6 chemists, 2 chemical 
engineers and a number of physicists. Research committee of 7 mem- 
bers, comprised of the general superintendent and the head of each 
manufacturing department. 

Research work: The greater part of the time of the members of 
the research committee, as well as that of all the chemists, is spent on 
research or development work on synthetic gums, treated oils, var- 
nishes, paints, enamels, stains, dry colors, and insecticides. 

Equipment: Stacks for oil boiling and varnish making; an elec- 
trically heated humidor, the humidity and temperature of which can 
be controlled and regulated to duplicate the conditions of various 
manufacturing plants; an oil treating plant and spraying apparatus. 

204. Globe Soap Company, The, St. Bernard, Ohio. 

Research staff: C. P. Long, chemical director, 3 chemists and 2 
chemical engineers. 

Research work : One-tenth time of 6 on investigation of problems 
connected with the industry. 

205. Glysyn Corporation, The, New York, N. Y. Laboratory at 
Bound Brook, N. J. 

Research staff : Harold F. Saunders and 3 chemists. 
Research work : Full time of 4 on chlorination processes. 

206. 'Goodrich, B. F., Company, The, Akron, Ohio. (Rubber goods 
of every description.) 

Research staff: W^ C. Geer, vice-president, in charge of develop- 
ment. Research physical laboratory: 4 physicists and 4 assist- 
ants. Engineering and testing laboratory: 3 engineers and 2 engi- 
neering assistants. Chemical laboratories: 8 chemists and 3 assist- 
ants. Development laboratories: 18 chemical engineers and 26 
assistants. 

Research work: The entire time of the staff is spent on research 
and factory control work, although in rubber the factory control is 



INDUSTRIAL RESEARCH LABORATORIES 37 

never quite distinguishable from research. The fundamental lines of 
research are those of compounding ingredients, including the chemical 
and physical properties of crude rubber, reclaimed rubber, mineral 
ingredients, and organic chemical individuals, the study of vulcaniza- 
tion, and in particular the main efforts have to do with the physical 
and chemical design of compositions and articles for particular lines 
of industrial service. 

Equipment: Development laboratory equipped with mills, vul- 
canizing apparatus, etc. 
307. Goodyear Tire & Rubber Company, The, Akron, Ohio. 

Research staff: Wm. S. Wolfe, development manager, K. B. Kil- 
bom, experimental engineer in charge of machine design, tire desi|^ 
and highways transportation divisions; R. C. Hartong, chief chemist 
in charge of development service and chemical and physical research ; 
W. E. Shively, chief tire designer, H. E. Morse, manager mechanical 
goods development and service division; 4 chemical engineers, 3 as- 
sistant chemical engineers, 8 research chemists, 5 research physical 
chemists and physicists, 9 research engineers, 25 technical service, 
chemical and mechanical engineers, 8 chemical laboratory chemists 
and assistant chemists, 18 physical laboratory assistants, 8 mechanical 
goods design engineers, 11 tire design engineers, 6 assistant tire de- 
sign engineers, 12 compound development chemists, 6 machine design 
engineers, 12 machine designers, 5 machine design detailers and 
tracers, 37 machine design workshop machinists, 10 machine design 
expert template makers, 2 highway transportation engineers. Total 
employees of department approximately 360. 

Research work: Full time of research and development men on 
mechanism of vulcanization, compounds which affect the rate of vul- 
canization, development of organic compounds especially adapted to 
rubber work ; application of physical chemistry to study of rubber and 
compounding materials; physical properties of rubber, and methods 
of testing and studying them ; chemistry of fibrous materials, particu- 
larly cotton, and properties of materials used as films or protective 
agents; industrial processes, such as reclaiming and coagulation of 
rubber. 

ao8. Grasselli Chemical Company, 1300 Guardian Bldg., Cleveland, 
Ohio. Laboratory at Cleveland mainly for inorganic work. Labora- 
tory also at Grasselli, N. J., for organic work strictly. 

Research staff: Henry Howard and a large number of chemists 
and assistants. 

Research work: Full time of staff on problems connected with 
possible improvements in products at present being manufactured as 
well as in connection with chemicals, dyes, intermediates, etc., the 
manufacture of which is being contemplated. 

209. Gray Industrial Laboratories, The, 961 Frelinghuysen Ave., 
Newark, N. J. 

Research staff: Thomas T. Gray, David Drogin, G. C. Hargrove, 
E. V. Espenhahn and assistants. 

Research work : Full time of 2 on petroleum and its products. 

Equipment: Complete semi-commercial oil refining equipment. 



38 INDUSTRIAL RESEARCH LABORATORIES 

2Z0. Great Western Electro-Chemical Company, 9 Main St., San 
Francisco, Calif. (Chlorine products.) 

Research staff : Ludwig Rosenstein, 2 chemists and 2 assistants. 

Research work: Utilization of chlorine, manufacture of chlorine 
products, manufacture of caustic and electrolysis of brine, 
azz. Great Western Sugar Company, The, Sugar Building, Denver, 
Colo. 

Research staff: H. W. Dahlberg, i chief chemist, 4 chemical engi- 
neers, 4 research chemists, 2 mechanics, i experimental process man, 
3 analysts. 

Research work: Full time of 16 on investigations of fundamental 
principles of processes and practices now in use, examination of pro- 
posed new processes and apparatus and study of utilization of by- 
products and waste products; production of crude potash, sodium 
cyanide, ammonium sulphate and certain rare organic chemicals from 
the Steffen's waste water; refining of crude potash leading to pro- 
duction of carbonate, hydrate, etc.; recovery of organic acids from 
waste waters. 

Equipment: Complete equipment for manufacture of sugar on a 
small scale under such conditions that special attention may be paid 
to any stage of the process. 

2xa. Grosvenor, Wm. M., 50 E. 41st St., New York, N. Y. (Con- 
sulting chemist and factory engineer.) 

Research staff: From 2 to o. 

Research work: Flotation of ores, non-ferrous metallurgy, paper, 
starch, glues and adhesives, textiles, paper and their finishing, 
methods of manufacture of organic intermediates, utilization of by- 
and waste products. 

Equipment: Viscosimeters, high speed moving picture equipment, 
autoclaves up to 1000 lbs. per sq. in. 

2x3. Gulf Pipe Line Company, Houston, Tex. (Producers and trans- 
porters of petroleum.) 

Research staff: F. M. Seibert and 2 trained research men. 

Research work: Full time of 3 on methods for production and 
transportation of oil ; special problems on treatment of crude oil emul- 
sions, conservation of oil, gas, etc. 

2x4. Gurley, W. & L. E., 514 Fulton St., Troy, N. Y. (Instruments 
for civil, mining and hydraulic engineers, and land surveyors.) 

Research staff: E. W. Arms, 3 engineers, 3 mechanicians and as- 
sistants as needed. 

Research work : Practically full time of 7 on investigations for de- 
sign and manufacture of instruments for civil, mining and hydraulic 
engrineers, such as automatic water stage registers, current meters, 
hook gages, transits and levels. 

Equipment: For testing and calibrating standard precision meas- 
ures of weight, capacity and length ; for investigation of water meas- 
urements and for design of instruments for this purpose; automatic 
water stage registers, current meters and hook gages; special divid- 
ing engfines for accurate angular and linear graduation ; for drawing 
platinum wire from o.ooi- to 0.00002-inch diameter for cross-wire reti- 
cles and in research experiments. 



INDUSTRIAL RESEARCH LABORATORIES 39 

2x5. Habirshaw Electric Cable Company, Inc., Yonkers, N. Y. 

Research staff: William A. Del Mar, 3 to 6 engineers, 2 to 6 chem- 
ists and o to 7 assistants. 

Research work: Seven-tenths time of staff on insulating materials 
and electric cable manufacture. 

Equipment : Miniature manufacturing plant for making rubber in- 
sulated wire in the laboratory. 
2x6. Hamersley MTg Co., The, Garfield, N. J. (Waxed papers.) 

Research staff: i chemical engineer and 5 chemists. 

Research work : One-third time of 6 on pulp, paper, and paper mill 
chemicals. 

Equipment: Well equipped for paper mill experiments on semi- 
commercial scale. 

2x7. Harbison-Walker Refractories Company, Farmers Bank Build- 
ing, Pittsburgh, Pa. (Fire-clay, silica, magnesite and chrome bricks 
and other refractory products.) 

Research staff: R. H. Youngman, i to 2 special technical men, i 
chief chemist and i or 2 chemists. 

Research work: One-half time of staff on problems in connection 
with refractories. 

Equipment : i coal and i gas-fired test kiln, i small ore crusher, 2 
Braun planetary pulverizers and'i hydraulic press of 104 tons capacity. 
218. Harrison Mfg. Co., The, 55 Union St., Rahway, N. J. (General 
chemicals and chemical products ; thorium nitrate and other rare earth 
salts and oxides; writing inks.) 

Research staff: C. W. Squier. 

Research work: Full time of i on general lines of research. 

Harrison Safety Boiler Works. See Cochrane, H. S. B. W., 
Corporation (p. 20). 

2xg. Hayes, Hammond V., 84 State St., Boston, Mass. (Consulting 
engfineer.) 

Research staff: Hammond V. Hayes, 5 electrical engineers and 
physicists. 

Research work : Full time of 6 on electro-dynamic problems. 

Hajmes Stellite Co. See Union Carbide and Carbon Research 
Laboratories, Inc. (p. 78). 

220. Heap, William, & Sons, Grand Haven, Mich. (Celluloid and 
china.) 

Research staff: H. Stirling Snell and i chemist. 

Research work : Three-fourths time of 2 on thermoplastics. 

221. Heinrich Laboratories of Applied Chemistry, looi Oxford St., 
Berkeley, Calif, (formerly Tacoma, Wash.). 

Research staff : E. O. Heinrich and i chemist. 

Research work : Full time of 2 on chemical and photomicrographi- 
cal problems as applied to criminal investigation. 
222-224. Hercules Powder Co., Wilmington, Del. (Explosives.) 
Laboratories at Kenvil, N. J., Brunswick, Ga., and Emporium, Pa. 
Executive staff, consisting of G. M. Norman and 6 assistants, super- 
vises work on problems on explosives, mineral acids, nitrogen fixa- 
tion, pyroxylin solutions, plastics, smokeless powder, and naval stores 
at three research laboratories. 

222. Experimental station, Kenvil, N. J, 



40 INDUSTRIAL RESEARCH LABORATORIES 

Research staff: C. 1^. Bierbauer, i6 graduate chemists and engi- 
neers, 7 other salaried employees and 24 payroll employees. 

Research work : Approximately full time of 48 on research on high 
explosives, smokeless powders, plastics, pyrox;y^lin solutions, and naval 
stores. Some time also devoted to investigations of analytical meth- 
ods in reference to above. 

Equipment: Complete equipment for testing properties of dyna- 
mite. Equipment for manufacturing propellant powders, and ranges 
for testing same for velocity and pressure, semi-works equipment for 
the manufacture of organic chemicals and plastics. 

223. Naval Stores Laboratory, Brunswick, Ga. 

Research staff: C. M. Sherwood and 3 graduate chemists. 

Research work : Seven-tenths time of 4 on problems connected with 
the manufacture of turpentine, rosins and pine oil, by the steam sol- 
vent process. 

Equipment: Semi- works scale apparatus duplicates plant process. 

224. Emporium Research Laboratory, Emporium, Pa. 

Research staff: R. B. Smith and i assistant chief chemist, 5 as- 
sistant chemists and 2 laboratory assistants. 

Research work : Full time of 10 on general research and on meth- 
ods of manufacture of mineral acids and domestic explosives. 

Equipment : Semi-commercial scale apparatus for nitration ; special 
equipment for analysis of explosives and for explosive testing. 

Hes8-Bright Manufacturing Co. See S. K. F. Industries, Inc. 

(p. 72). 

335. Heyden Chemical Company of America, Inc., Garfield, N. J. 

Research staff: Robert O. Bengis, 7 chemists, i engineer and i 
laboratory assistant. 

Research work: Two-fifths time of 10 on medicinal and pharma- 
ceutical chemistry ; salicylates and metallic colloids. 

Equipment : Equipped semi-commercial plant adjacent to research 
laboratory. 

226. Hirsch Laboratories, Inc., The, 50 E. 41st St., New York, N. Y. 
Laboratory at 593 Irving Ave., Brooklyn, N. Y. 

Research staff: Alcan Hirsch and 5 chemists. 

Research work : One-half time of 6 on organic chemicals, interme- 
diates, dyestuffs and pharmaceuticals. Metal products; cerium, 
thorium and molybdenum products. 

Equipment: Fully equipped for semi-plant operations. Facilities 
for duplicating and testing on commercial scale any proposed plant in- 
stallation or process. 

Hirsch, Stein & Company. See United Chemical and Organic 
Products Co. (p. 79). 

227. Hochstadter Laboratories, 227 Front St., New York, N. Y. 
(General chemical analyses and investigations; consultants and tech- 
nical experts.) 

Research staff: Irving Hochstadter, W. B. Stoddard and 2 chemists. 

Research work: One-half time of 4 on manufacture and prepara- 
tion of food and pharmaceutical products with special emphasis on 
problems relating to pure food regulations and on problems relating 
to the rare metals, especially "Tungsten" compounds. 



INDUSTRIAL RESEARCH LABORATORIES 41 

aa8. Holt Manufacturing Company, The, Peoria, 111. (Tractors.) 

Research staff: R. M. Hudson, research engineer, and 2 mechani- 
cal engineers; F. W. Grotts, inspection and metallurgical engineer, 
and 2 chemists; i expert in microphotography. 

Research work : Full time of supervisors and staff on technical, in- 
dustrial and commercial problems. Industrial research on wage sur- 
veys, costs of living, industrial relations and organization problems 
and principles. 

Equipment: Special microphotographic apparatus with grinding 
and polishing machines; oil distillation apparatus and viscosimeter ; 
electric furnace for experimental heat treating; dynamometer for 
motor research. 
aag. Hood Rubber Company, Watertown, Mass. 

Research staff: Warren E. Clancy, 2 chemists and several routine 
assistants. 

Research work: Small part time of staff on new methods of ex- 
amination of materials ; study of various organic derivatives. 

Equipment : Devices and machines for testing rubber, cloth, yarns ; 
large experimental mill room equipped with heavier machinery and 
heavier testing machines for testing tires (solid, pneumatic, etc.). 

330. Hooker Electrochemical Company, Niagara Falls, N. Y. 
Research staff: T. L. B. Lyster, director of development, A. H. 

Hooker, technical director, W. J. Marsh, research chemist, i research 
chemist and 4 assistants. 

Research work: Full time of 5 on development of new processes 
and betterment of present processes. 

Equipment: Furnace room, annex and industrial laboratory 
equipped for intermediate scale or development work. 

331. Hoskins Manufacturing Company, Lawton Ave., at Buchanan, 
Detroit, Mich. (Electric-furnaces, pyrometers and heating ap- 
pliances.) 

Research staff : W. A. Gatward and 4 engineers. 
Research work : Almost full time of 5 on the improvement and pro- 
duction of alloys and allied products. 

332. Houghton, E. F. & Co., 240 W. Somerset St., Philadelphia, Pa. 
(Oils, mechanical leathers and steel heat treating materials.) 

Research staff: George W. Pressell, 9 chemists and engineers. 
Consulting engineers and chemists sometimes employed. 

Research work : Research staff is working constantly in producing 
oils for the industries, mechanical leathers and steel treating materials ; 
also improving methods in the manufacturing industry. 
233. Howard Wheat and Flour Testing Laboratory, The, Old Colony 
Building, Minneapolis, Minn. (Comparative baking tests, records and 
reports, milling tests, chemical and microscopical analyses.) 

Research staff : C. H. Briggs and 3 chemists. 

Research work : Small part time of 4 on problems connected with 
causes of peculiar variations of wheats and other cereals when baked 
into bread or used for other food purposes ; efforts to improve methods 
of separation of wheat proteins; improved methods of quantitative 
analysis; chemical causes of loaf expansion and effects of various 



42 INDUSTRIAL RESEARCH LABORATORIES 

activating materials in bread making, carried out by cooperation of 
baking and chemical departments. Some work on distinguishing 
cereal flours one from another. 

Equipment: Moisture testers for grain, haemocytometer, yeast 
testing apparatus of special design, wheat and grain cleaning and 
milling department and a baking test department, equipped for hand- 
ling more than loo individual tests daily with automatic control of 
kneading machines, bread raising cabinets, etc. 

234« Hunt, Robert W.» and Co.» 175 W. tackson Blvd., Chicago, 111. 
(Engfineers.) Laboratories also at 251 Kearney St., San Francisco, 
Calif. ; 90 West St., New York, N. Y. ; Monongahela Bank Bldg., Pitts- 
burgh, Pa. ; 905 McGill Bldg., Montreal, Canada ; and Syndicate Trust 
Bldg., St. Louis, Mo. 

Research staff: J. H. Campbell and assistant, 12 chemists and 8 
engineers. 

Research work : Part time of 22 on materials of construction, iron, 
steel, stone, cement and bitumen. 

235. Hyco Fuel Products Corporation, 30 Broad St., New York, N. Y. 
Laboratory at Edgewater, N. J. 

Research staff: Allen Rogers, 3 chemists, i engineer, i draftsman 
and 5 assistants. 

Research work : The plant is built for demonstration and research 
on oil problems, especially as related to motor fuel. 

236. Hynson, Westcott & Dunning, 423 N. Charles St., Baltimore, 
Md. (Bacterial and bio-chemic therapeutic products.) Laboratory 
at 16 E. Hamilton St, Baltimore, Md. 

Research staff: Daniel Base, 2 chemists, i pharmacologist and i 
bacteriologfist. 

Research work: One-half time of 5 on preparation and pharma- 
cological testing of new drugs. 

237. Imperial Belting Company, Lincoln and Kinzie Sts., Chicago, 111. 
(Belting and conveyors.) Laboratory at 400 N. Lincoln St., Chicago, 
111. 

Research staff: James A. Millner, i engineer and 2 chemists. 
Research work: Approximately one-half time of 4 on oils, paints, 
asphalts and textiles. 

238. Industrial Chemical Institute of Milwaukee, 200 Pleasant St, 
Milwaukee, Wis. (Consultants for chemical and engineering prob- 
lems.) 

Research staff : F. M. Dupont, i chemical engineer, i bacteriologist 
and 4 chemists. 

Research work: Full time of i chemist on food, beverage, mag- 
nesite, lime, adhesives, antisepticides and general matters. 

239. Industrial Research Corporation, 1025 Front St., Toledo, Ohio. 
Research staff : C. P. Brockway and 2 engineers. 

Research work: Full time of 3 on problems related to small 
machine equipment and small devices in metal. 

240. Industrud Research Laboratories, 190 N. State St., Chicago, 111. 
F. Peter Dengler, Inc., proprietors. (General consulting and research 
chemists, resource and chemical engineers.) 

Research staff : F. Peter Dengler, 5 or 6 chemists and i engineer. 



i 



INDUSTRIAL RESEARCH LABORATORIES 43 

Research work: Full time of staff on manufacturing and research 
problems relative to cement, coal, corn, cotton seed, drugs, dairy, dyes, 
foods, minerals, paints, paving, petroleum, paper, sewage, soap, steel, 
sugar, tobacco, water, barley, conservation of waste material and 
manufacture of non-alcoholic flavoring extracts including vanilla. 

Equipment : Commercial equipment for production of coke and by- 
products and for decolorizing and reclaiming cloth, mill ends, flour 
bags, sugar bags, all cloth signs and rubber-coated textile materials. 
Commercial equipment for extracting vegetable alkaloid from tea and 
coflFee. Apparatus for the manufacture of non-alcoholic extracts is 
being installed on a commercial scale for immediate use. 

241. Industrial Testing Laboratories, 402 West 23rd St., New York, 
N.Y. 

Research staff: Emil Schlichting, director, H. Winther, chief 
chemist, and 5 assistant chemists. 

Research work : Part time of staff on problems related to beverage, 
fermentation and food industries. 

Equipment: For chemical, biological and microscopical analyses 
of beverages and foods, their raw materials, by-products, and acces- 
sories. 

242. Industrial Works, Bay City, Mich. 

Research staflF : R. H. Morgan, metallurgist, J. C. Wheat, develop- 
ment engineer; chemists and assistants as required. 

Research work: Heat treatment and properties of metals, proper- 
ties of other materials, development and control of foundry practice 
for iron, steel and bronze ; welding practice. Development of cranes 
and accessories to meet needs of users ; statistical manufacturing and 
executive control; standards of production and personnel, standard 
times and routings. 

Equipment: 150,000-pound Riehle testing machine. Shore sclero- 
scope. Berry strain gauges, two proof testing machines of 500,000 
pounds and 100,000 pounds capacity, for testing actual parts before 
assembly. 

243. Ingersoll-Rand Company, 11 Broadway, New York, N. Y. 
(Rock drills, etc.) 

Research staff: F. W. O'Neil and a number of assistants. 

Research work : Full time of some and part time of others on drills, 
pumps, pneumatic tools, compressors, blowers, condensers and oil 
engines. 

244. Inland Steel Company, Indiana Harbor, Ind., 

Research staff: J. C. Dickson, 29 chemists and 5 chemical 
engineers. 

Research work: Full time of 4 and part time of 30 on problems 
connected with steel industry. 

245. Institute of Industrial Research, The, 19th and B Sts., N. W., 
Washington, D. C. 

Research staff: Allerton S. Cushman, chemists, physicists and as- 
sistants as needed. 

Research work : Varying part time of staff on physical testing of 
cements, rocks, clays, brick, block, iron, steel, wood, rubber, and other 
materials of construction. In Bitumen Laboratory petroleum and 



44 INDUSTRIAL RESEARCH LABORATORIES 

petroleum products, tars and tar products, creosoting oils, asphalts, 
bituminous emulsions, bituminous aggregates, and all other types of 
chemical road and paving materials, roofing materials, rubber, etc., are 
examined and tested. Chemical examinations of rocks, clays, cements, 
etc., are made and researches conducted on improvements in industrial 
products and processes and utilization of waste products for road pur- 
poses. 
Equipment : For cement and bitumen. 

346. International Filter Co., 38 S. Dearborn St., Chicago, 111. (Water 
softening and filtration plants.) Laboratory at 333 W. 25th Place, 
Chicago, 111. 

Research staff : 2 to 5 workers. 

Research work: Approximately one-half time on materials, meth- 
ods and processes for purifying liquids. 

347. International Nickel Company, The, Bayonne, N .J. Successors 
to The Orford Copper Co. 

Research staflF: raul D. Merica, 2 metallurgists, 2 assistant metal- 
lurgists, 2 chemists, 2 laboratory assistants, and i machinist. 

Research work: Metallurgy of copper and nickel; physical prop- 
erties of nickel and Monel metal; uses of Monel metal and nickel 
alloys. 

Equipment : Laboratory electric furnace equipment ; dust and fume 
sampling apparatus ; experimental electroplating plant. 
948. International Shoe Co. (Burke Tannery), Morganton, N. C. 

Research staff : J. S. Rogers, 2 trained assistants, and i helper. 

Research work : Approximately one-half time of director and part 
time of assistants on problems in extraction of tanning materials and 
the tanning and finishing of sole leathers. 

Equipment: Some special apparatus for small scale plant experi- 
ments. 

249. International Silver Company, Meriden, Conn. 
Research staff : Chas. E. Skidgell and 2 chemists. 
Research work : Small part time of 3 on electro-plating. 

250. Interocean Oil Company, The, East Brooklyn, Baltimore, Md. 
Research staff : H. R. Gundlach, 2 chemists and 6 assistants. 
Research work : Approximately one-tenth time of 9 on development 

of refining methods and testing ; recovering of waste products, etc. 

Equipment: Laboratory scale refinery, also larger scale experi- 
mental plant. 
351. James Ore Concentrator Co., 35 Runyon St., Newark, N. J. 

Research staff: U. S. James, i metallurgical engineer and 3 assist- 
ants. 

Research work : Full time of 3 on ore and coal testing. 
353. Jaques Manufacturing Company, i6th and Canal Sts., Chicago, 
111. (Manufacturers of K. C. baking powder.) 

Research staff : J. R. Chittick and 3 chemists. 

Research work : One-third time of 2 on leavening materials. 

Jeffrey-Dewitt Co. See Champion Porcelain Company (p. 19). 
353. Johnson & Johnson, New Brunswick, N. J. (Surgical supplies.) 

Research staff : Fred B. Kilmer and 7 assistants. 

Research work : One-third time of 8 in research on medical, surgical 



INDUSTRIAL RESEARCH LABORATORIES 45 

and hospital supplies (not equipment) and incidentally drugs and 
commodities used therein. 

254. Kalmus, Comstock & Wescott, Inc.» no Brookline Ave., Boston, 
Mass. (Consulting, research and operating engineers.) 

Research staff: A group of physicists, chemists, metallurgists and 
chemical engineers of from 20 to 25 in number, directed by Herbert T. 
Kalmus, Daniel F. Comstock and E. W. Westcott. 

Research work : Full time of staff on mechanical, physical, chem- 
ical, electrochemical, metallurgfical and photographic lines leading to 
the development of processes, use of waste products, and through the 
designing, constructing and early operating of plants. 

Equipment : Specially designed equipment in the fields of ceramics, 
abrasives, general chemical engfineering, metallurgy, photography, 
motion pictures, and vegetable oils. 

255. Kellogg Switchboard and Supply Co.» Adams and Aberdeen Sts., 
Chicago, 111. 

Research staff: Wilbur J. Anglemyer, i electrical engineer and 5 
assistants. 

Research work: Full time of 6 on testing of materials including 
analysis, tensile strength tests and magnetic characteristics ; checking 
methods of manufacture and development of special testing instru- 
ments and new products. 

Equipment : Impregnating apparatus, 5000 and 50,000 volt testing 
transformers, Burrous permeameter, Rowland dynamometer, G. E. 
Co. oscillograph, centrifugal extractor, apparatus for testing textile 
materials and paper and insulation testing equipment. 

256. Keuffel & Esser Co., Hoboken, N. J. (Drawing materials and 
mathematical and surveying instruments.) 

Research staff: Carl Keuffel, i chemist, 2 assistant chemists, 2 
optical engineers, and 2 assistants. 

Research work: One-half time of 8 on optical glass and various 
articles manufactured, including design of optical instruments and 
calculation of optical systems. 

Equipment : Special equipment for testing presence of small quan- 
tities of iron in silicates, and for physical, chemical and microscopic 
testing of papers. Optical laboratory equipped for general testing of 
optical instruments. 

257. Kidde, Walter, & Company, Incorporated, 140 Cedar St., New 
York, N. Y. (Engineers and constructors.) 

Research staff : Barzillai G. Worth and assistants as necessary. 

Research work : Investigation for clients, such as electrolysis of 
potassium and sodium compounds ; electrochemical extraction of oils ; 
chemical salvage systems for tanneries ; sanitation of tannery effluent, 
etc. 

258. Kilbourne ft Clark Manufacturing Company, Seattle, Wash. 
(Engineers and manufacturers of electrical and radio apparatus.) 

Research staff: H. F. Jefferson and 5 men. 

Research work : Time of staff as occasion requires, on testing and 
investigating high-frequency circuits. 

Equipment: Wave-meters, decremeters, sphere spark gap (25 cm. 
sphere) for high voltage tests; condensers, variable and fixed, with 
air, mica and oil dielectrics ; inductances in various forms for high and 



46 INDUSTRIAL RESEARCH LABORATORIES 

low voltage; 500-cycle meters for use in connection with audio- 
frequency circuits in radio work. 

Kistler, Lesh & Company. See International Shoe Co. (p. 44). 

259. Klearflax Linen Rug Company, 63rd and Grand Aves., West, 
Duluth, Minn. (Linen rugs and carpeting.) 

Research staff : Charles F. Goldthwait and variable number of as- 
sistants. 

Research work : Full time of staff on use of flax fibre and its by- 
products ; humidity, textiles and mechanism of dyeing process. 

260. Kokomo Steel and Wire Co., Kokomo, Ind. 
Research staff : R. K. Clifford, 2 chemists and 2 assistants. 
Research work: One-third time of 5 on standardization of raw 

materials, specifications and improvement of products in connection 
with manufacture of open hearth steel, wire and wire products. 

Equipment : 100,000-pound Olsen testing machine, Brinell machine, 
electric furnace for heat treatments, metallographic equipment for 
grinding, polishing and microphotography. 

261. Kolynos Co., The, New Haven, Conn. (Dental cream.) 
Research staff : L. A. Jenkins, 3 chemists and 2 bacteriologists. 
Research work : One-half time of 6 on oral hygiene. 

262. Koppers Company, The, Pittsburgh, Pa. (Designers and 
builders of by-product coke and gas plants and apparatus for benzol 
recovery, tar distillation and gas purification.) 

Research staff: F. W. Sperr, Jr., 13 graduate chemists, i engineer 
and 4 assistants. 

Research work : Full time of I9 on coal carbonization, gas produc- 
tion, and purification, by-product recovery, secondary treatment of 
various by-products, general fuel research, refractories, pyrometry, in- 
vestigation of coal properties. 

Equipment: Special apparatus for coal carbonization at high and 
low temperatures, coal washing, coke research, gas purification by 
dry and liquid processes, furnaces for investigation of refractory ma- 
terials at high temperatures, laboratories and experimental plant 
fully equipped for semi-commercial tests, and plants available for 
large scale tests in relation to coke and gas manufacture and by-prod- 
uct recovery. 

263. Kraus Research Laboratories, Inc., 130 Pearl St., New York, 
N. Y. (Consulting engineers in refractories.) 

Research staff : Charles E. Kraus, 2 ceramists, 2 research engineers 
and 2 assistants. 

Research work: Three-fourths time of 7 on ceramics and refrac- 
tories. 

Equipment: Equipped to make all standard tests on refractory 
materials, both in raw and finished state. 

264. Krebs Pigment and Chemical Co., The, Newport, Del. 
Research staff : H. W. Fox, i chemical engineer, 2 chemists and 2 

assistants. 

Research work : Full time of 6 on properties of lithopone ; efficiency 
of steps of process. 

265. Kulhnan, Salz & Co., 603 Wells Fargo Building, San Francisco, 
Calif. (Tanners.) 



INDUSTRIAL RESEARCH LABORATORIES 47 

Research staff: i chemist and i helper. 

Research work: Variable amount of time of 2 on science of tan- 
ning. 

266. Laclede-Christy Clay Products Company, 4600 S. Kingshighway, 
St. Louis, Mo. 

Research staff: C. W. Berry and i assistant. 

Research work : One-half time of 2 on development of refractories, 
superior clays for use in paper, graphite crucibles, enamels; unusual 
basic and neutral refractories, such as high aluminous materials, com- 
binations of alumina and magnesia. 

267. Lakeview Laboratories, 2 Jersey St., Buffalo, N. Y. 
Research staff: A. L. Stevens and 2 assistants. 

Research work : Four-fifths time of 3 on wood oils and tars. 
a6S. Larkin Co., 680 Seneca St., Buffalo, N. Y. (Soap.) 

Research staff : L. F. Hoyt, 4 chemists and 2 assistants. 

Research work: Three-fourths time of 7 on soaps, fats and oils; 
development along miscellaneous lines of new products for the com- 
pany. 

Equipment: Small experimental plant for producing soap. 
269. Laucks, L F., Inc., 99 Marion St., Seattle, Wash. (Analytical 
and consulting chemists, assayers and metallurgists.) 

Research staff : L F. Laucks and H. P. Banks, 3 chemists, 3 chemi- 
cal engineers, 2 agronomists and 3 inspection engineers. 

Research work: One-fourth time of 8 on uses for raw materials 
available in the Orient and adaptation of these materials to American 
requirements; development of improvements in manufacturers' proc- 
esses and development of coal by-products. 

Equipment : Complete vegetable and fish oil refinery and complete 
coal by-products plant. 
370. Lee & Wight, 113 E. Franklin St., Baltimore, Md. 

Research staff: Two chemists. 

Research work: Part time of 2 on industrial and miscellaneous 
problems. 

271. Leeds & Northrup Company, 4901 Stenton Ave., Philadelphia, 
Pa. 

Research staff: Irving 6. Smith, 7 trained research workers and 3 
mechanicians. 

Research work: Full time of 11 on development of apparatus for 
precise measurements in heat, electricity, magnetism and heat treat- 
ment of steel; also for research and control in chemical industries. 

Equipment : Apparatus for heat treatment of steel, instruments for 
precise measurements in heat, electricity and n^agnetism. 

372. Lehn & Fink, Inc., 192 Bloomfield Ave., Bloomfield, N. J. (An- 
tiseptics, disinfectants, drugs, medicines, dentifrice, soaps, fine chemi- 
cals.) 

Research staff : C. Hinck, 14 chemists and 2 engfineers. 
Research work: Full time of 17 on organic, biological and pharma- 
ceutical problems. 

373. Lemoine, Pierre, Cic., Inc., 294 Pearl St., New York, N. Y. (Es- 
sential oils, aromatic chemicals.) Factory Laboratory at L. I. City, 
N.Y. 



AS INDUSTRIAL RESEARCH LABORATORIES 

Research staff: 2 chemical engineers, i analytical and research 
chemist and 2 associate chemists. 

Research work : Part time of 5 on synthetic organic chemicals and 
essential oils, perfumery oils and raw materials and flavors and flavor- 
ing raw materials. 

274. Lennox Chemical Co., The, 1205 E. 55th St., Cleveland, Ohio. 
Laboratory at Euclid, Ohio. 

Research staff : A. S. Allen and 2 assistants. 

Research work : One-half time of 3 on carbonation as related to the 
soft drink or beverage industry ; liquefaction, purification and drying 
of commercial gases as oxygen, nitrous oxide, and carbon dioxide. 

275. Lewis, F. J., Manufacturing Co., 2513 S. Robey St., Chicago, 
111. 

Research staff: W. 6. Murphy and 2 chemical engineers. 
Research work : Part time on coal tar products. 

Lewis, Gilman & Moore. See Metals & Chemicals Extraction 
Corporation (p. 52). 

276. Lilly, Eli, and Company, Indianapolis, Ind. (Pharmaceutical 
and biologfical products.) 

Research staff: G. H. A. Clowes, Frank R. Eldred, A. L. Walters 
and about 40 chemists and pharmacologists. 

Research work: Full time of 8 men and half time of 17 directed to 
development of new therapeutic agents and to broad stud^ of mode 
of action of drugs from physical, chemical and physiological stand- 
points. 

277. Lincoln, E. S., Inc., 534 Congress St., Portland, Me. (Consult- 
ing engineers ; electrical laboratories.) 

Research staff: E. S. Lincoln and 3 engineers. 

Research work : Full time of 4 on electrical problems. Field work 
a specialty. 

Linde Air Products Company, The. See Union Carbide and 
Carbon Research Laboratories, Inc. (p. 78). 

278. Lindsay Light Company, 161 E. Grand Ave., Chicago, 111. 

Research staff : H. N. McCoy, 8 chemists and i engineer. 

Research work: Four-fifths time of 10 on improvements of proc- 
esses of refining thorium nitrate, cerium compounds, organic prepara- 
tions such as phenolphthalein and vanillin, preparation of dyes. 

279. Little, Arthur D., Inc., 30 Charles River Road, Cambridge 39, 
Mass. (Chemists, engineers, managers.) 

Research staff: Earl P. Stevenson, director, and 8 research chem- 
ists cooperating with 10 analytical chemists; 8 engineers, chemical, 
mechanical, mining; i economic geologist; and special staff for valua- 
tions and appraisals. 

Research work : Full time of 10 on industrial research on lines de- 
termined by requirements of clients and on special problems in adhe- 
sives, ceramics, utilization of lumbering waste, paper and pulp, tex- 
tiles, metallurgy, non-metallic minerals, and process developments. 

Equipment : Complete experimental paper mill including a 30-inch 
Fourdrinier machine. Semi-commercial equipment for miscellaneous 
work. 



INDUSTRIAL RESEARCH LABORATORIES 49 

a8o. Littlefield Laboratories Co., Seattle, Wash. 

Research staff: E. E. Littlefield, i electrochemist and electro- 
physicist, I chemist and i mechanical engineer. 

Research work : Full time of i and part time of 3 in chemical, elec- 
trical and electrochemical fields ; development of special apparatus for 
initiating and stopping flow of liquids by varying conductivity ; elec- 
trical treatment of vegetation. Usually done in connection with large 
industries in the United States and England. 
aSz. Lockhart Laboratories, 33^ Auburn Ave., Atlanta, Ga. 

Research staff: L. B. Lockhart. 

Research work : Full time of i on lubricating oils and greases, spe- 
cial soaps, varnishes, waterproofing, petroleum products, colloids and 
emulsions. 

aSa. Long, W. H., & Co., Inc., 244 Canal St., New York, N. Y. 
(Wholesale druggists.) 

Research staff: Charles H. Lewis, 2 chemists, i assistant and i 
laboratory assistant. 

Research work: Drugs, chemicals and dyes. 

283. Ludlum Steel Company, Watervliet, N. Y. 
Research staff: P. A. E. Armstrong and 4 trained men. 
Research work: Full time of 5 on improvement of manufacturing 

methods for ferro alloys and certain steels, such as magnet steel and 
non-corrosive steels and methods of chemical analysis of steels and 
ferro alloys. 

284. Lumen Bearing Company^ Buffalo, N. Y. (Brass and bronze 
foundry.) 

Research staff: C. H. Bierbaum, metallurgist; B. Woiski, chief 
chemist, and 2 assistants, and G. F. Comstock, consulting metallurgist. 

Research work : Varying portion of time on problems having to do 
with non-ferrous metallurgy and metallography, chemistry as applied 
to non-ferrous metals, photomicrography of the non-ferrous metals. 

Equipment : 50,000-pound Olsen universal testing machine, Brinell 
hardness machine, scleroscope, microcharacter. 

285. Lunkenbeimer Co., The, Cincinnati, Ohio. (Valves, pipe fit- 
tings and other metal specialties.) 

Research staff: George K. Elliott and 7 assistants. 

Research work : Two-fifths time of 8 on metallurgical problems and 
corrosion. Generation and handling of saturated and super-heated 
steam; application of arc electric-furnace to production of malleable 
cast iron, special gray irons, and other high-carbon iron alloys. 

286. Ljrster Chemical Company, Inc., 61 Broadway, New York, N. Y. 
Laboratory at Passaic Junction, N. J. 

Research staff: William R. Lamar and 2 chemists. 

Research work : Full time of 3 on utilization of former waste prod- 
ucts in the rectification of wood tar oils for creosote and guaiacol; 
organic compounds and photographic developers and perfumery chem- 
icals. 

287. Maas, A. R., Chemical Company, 308 E. 8th St., Los Angeles, 
Calif. 

Research staff: Arthur R. Maas, 3 analytical chemists, i research 
chemist and i chemical engineer. 



so INDUSTRIAL RESEARCH LABORATORIES 

Research work: Manufacture of sulphites and other products, 
chiefly those derived from alkali and sulfur dioxide. 

Equipment: Absorption towers. 
388. HacAndrews & Forbes Company, 3d St. and Jefferson Ave., 
Camden, N. J. (Licorice extract, natural dyestuffs, wallboard and 
Foamite fire extin^ishers.) 

Research staff: Fercy A. Houseman, 6 chemists and 3 helpers. 

Research work : Approximately one-half time of 7 on constituents 
of licorice root and extract and development of Foamite fire extin- 
guishers. 

Equipment: Copper extractors, percolators and vacuum pans of 
laboratory size and semi-commercial size. 

289. HaUinckrodt Chemical Works, St. Louis, Mo. (Chemicals for 
medicinal, photographic, analytical and technical purposes.) 

Research staff: W. N. Stull, 22 chemists, 2 chemical engineers and 
I safety engineer. 

Research work : Full time of 5, one-half time of 4 and part time of 
others on improvement in processes of manufacture and methods of 
analysis. 

ago. Manhattan Rubber Mfg. Co., The, Passaic, N. J. (Mechanical 
rubber goods.) 

Research staff: W. L. Sturtevant, 6 chemists and 6 laboratory as- 
sistants. 

Research work : One-fourth time of 13 on rubber compounding and 
vulcanization. 

agz. Martin, Glen L., Company, The, 16800 St. Clair Ave., Cleveland, 
Ohio. (Builders of airplanes.) 

Research staff: Lessiter C. Milburn, i metallurgical engineer and 
I chemist. 

Research work : One-third time of 3 on new aircraft materials and 
check of aircraft designs, aircraft performance tests, and general air- 
craft development, metal construction, etc. 

Equipment: Rib testing machine (transverse loading distributed 
according to any pre-determined ratio). Combined pendulum tension 
machine and impact test machine, with interchangeable hammers 
(pendulums) and two ranges of capacity (200 and 1000 pounds). 

292. Martinez Refinery, Shell Co. of California, Martinez, Calif. 
Research staff: A. W. Jurrissen and 2 chemists. 

Research work : Varying portion time of 3 on treatment and pro- 
duction of petroleum products. 

Equipment : Large scale cracking apparatus and treating plant. 
Marvin-Davis Laboratories, Incorporated. See National Biscuit 
Company (p. 55). 

293. Matfaieson Alkali Works (Inc.), The, Niagara Falls, N. Y. 
Research staff : R. E. Gegenheimer, 7 chemists and 4 assistants. 
Research work: Full time of 6 on new process development and 

investigation of problems of electrolytic chlorin and caustic plant 
operation. 

294. May Chemical Works, 204 Niagara St., Newark, N. J. 
Research staff: Otto B. May and 2 assistants. 

Research work : One-half time of 3 on azo-dyes and intermediates. 



INDUSTRIAL RESEARCH LABORATORIES 51 

395* Masmard, T. Poole, Atlanta, Ga. (Geological and industrial en- 
gineering.) 

Research staff: T. Poole Maynard, i chemical engineer, i mining 
engineer and i civil engineer. 

Research work: One-third time on clays, bauxites, fullers earth, 
refractories, textiles, oil-cloth; recovery of potash from silicates, etc. 
296. M. B. Chemical Co., Inc., Johnson City, Tenn. 

Research staff : A. J. Buchanan and 2 chemists. 

Research work: Large part time of i chemist on dyes and inter- 
mediates. 

397. Mcllhiney, Parker C, 50 E. 41st St., New York, N. Y. 
Research staff: Parker C. Mcllhiney and 2 chemists. 

Research work: One-half time of 3 on investigation of paints and 
varnishes, hydrogenation processes, electrolytic processes, wood dis- 
tillation processes, shellac and other resins and fats and oils. 

398. McKesson & Robbins, Incorporated, 55 Berry St., Brooklyn, 
N. Y. (Drugs and chemicals.) Laboratory at 97 Fulton St., New 
York, N. Y. 

Research staff: E. H. Gane and 2 pharmaceutical chemists. 

Research work: Approximately one-half time of 3 on active prin- 
ciples of vegetable drugs, new medicinal compounds and drug stand- 
ards. 

299. McLaughlin Gormley King Co., 1715 Fifth St., S. E., Minne- 
apolis, Minn. (Drugs and herbs.) 

Research staff: C. B. Gnadinger and 2 chemists. 
Research work: Approximately one-half time of 2 on food prod- 
ucts, crude drugs and insecticides. 

300. McNab & Harlin Manufacturing Co., 55 John St., New York, 
N. Y. (Valves, fittings, etc.) Laboratory at 440 Straight St., Pater- 
son, N. J. 

Research staff: Ernest G. Jarvis, i assistant, 5 chemists, 6 metal- 
lurgists and 8 engineers. 

Research work: Approximately one-half time of 21 on rare metals 
and their uses in industrial alloys. 

Equipment : Electric laboratory melting furnaces, Hoskins type F. 
C. 106, miniature rolling mills and all necessary physical testing ma- 
chines and equipment for testing sheets, rods, wire and castings, and 
fully equipped metallographic department. 

30X. Meigs, Bassett & Slaughter, Inc., 210 S. 13th St., Philadelphia, 
Pa. (Chemical engineers.) Laboratory at Bala, Pa. 

Research staff : Harry P. Bassett, i chemical engineer and 3 chem- 
ists. 

Research work : Full time of 5 on paper, paper pulp, plastics, cellu- 
lose products, alkali and alkali salts. 
30a. Merck & Co., 45 Park Place, New York, N. Y. (Chemists.) 

Research staff : 2 trained chemists. 

Research work: Full time of 2 on problems incident to manufac- 
ture of the company's products. 

Equipment: Standard equipment for research in connection with 
manufacture of medicinal, analytical, photographic and technical 
chemicals. 



52 INDUSTRIAL RESEARCH LABORATORIES 

m 

303. Herrell. Wm. S., Company, The, 5th, Pike and Butler Sts., Cin- 
cinnati, Ohio. (Manufacturing pharmacists.) 

Research staff : 7 chemists, i chemical engineer and 4 pharmacists. 

Research work: Approximately full time of 3 and part time of 2 
on problems of manufacturing pharmaceuticals and pharmaceutical 
products. 

304. Merrell-Soule Laboratory, Ssrracuse, N. Y. 

Research staff: R. S. Fleming, 2 chemists and i assistant. An 
engineering department which does much work which might be classi- 
fied as research. 

Research work : Half time of 3 on food problems. 

Equipment: Experimental drying plant. 

305. Herrimac Chemical Company, North Woburn, Mass. 
Research staff : Lester A. Pratt and 9 chemists. 

Research work: Full time of staff on inorganic and organic re- 
search problems. 

Equipment: Industrial laboratory for carrying on large scale ex- 
periments. 

306. Hesabi Iron Company, Babbitt, Minn. 

Research staff: W. G. Swart, 3 engineers, 2 metallurgists and i 
chemist. 

Research work : One-half time of 7 on magnetic separation of ores 
and sintering. 

Equipment: Magnetic cobbers, classifiers and log washers and 
demagnetizers. 

307. MetaUoth Co., N. Y., Susq. & Western R. R. and Garibaldi Ave., 
Lodi, N. J. 

Research staff: Herbert B. Fenn. 

Research work : Part time of i on mildewproofing, fireproofing and 
waterproofing of cotton, flax and jute fabrics. 

Equipment: Apparatus for processing materials under conditions 
of actual commercial production. 

308. Metals & Chemicals Extraction Corporation, 1014 Hobart Bldg., 
San Francisco, Calif. (Heavy chemicals.) 

Research staff: L. H. Duschak and i chemical engineer. 
Research work : Inorganic chemistry, including the manufacture of 
heavy chemicals, potash, borax, barium compounds and acids. 

309. Metz, H. A., Laboratories, Inc., 122 Hudson St., New York, 
N. Y. Plant and laboratories, 642 Pacific St., Brooklyn, N. Y. 

Research staff : A. E. Sherndal, C. N. Myers, C. W. Hooper, G. P. 
Metz and 4 chemists. 

Research work : Studies of chemical, pharmaceutical and medicinal 
products; technical problems involved in their manufacture; path- 
ological, biological and bacteriological investigations relative to their 

use. 

310. Meyer, Theodore, 213 S. loth St., Philadelphia, Pa. 

Research staff: John K. Montgomery and 2 assistants. 

Research work: One-fourth time of 3 on antiseptics and insecti- 
cides. 

Midvale Steel Company, The. See Mid vale Steel and Ordnance 
Company. 



INDUSTRIAL RESEARCH LABORATORIES 53 

SIX. Midvale Steel and Ordnance Company, Nicetown Works, Phila- 
delphia, Pa. 

Research staff : A. H. Miller and 7 men. 

Research work : One-half time of 8 on investigation of characteris- 
tics of iron alloys, such as equilibrium diagrams, physical and mag- 
netic qualities, etc.; also the investigation of new alloys of steel for 
use in high service purposes. 

Equipment: Apparatus for several methods of obtaining critical 
temperatures, shock testing machines of Charpy and Izod t3rpes, 
Brinell and Shore hardness testing apparatus, magnetic testing appa- 
ratus of Koepsel and Burrows and experimental heat-treatment fur- 
naces of both gas and electric types. 

3za. Miller Rubber Co., The, Akron, Ohio. (Tires and other rubber 
goods.) 

Research staff : H. A. Morton and 3 chemists. 

Research work : Full time of 4 on rubber and organic chemistry. 

Equipment : Scott fabric tester, Curtis & Marbel fabric inspecting 
apparatus, tire testing apparatus, etc.; compounding laboratory mill 
and calendar, experimental press, etc. 

3x3. Milliken» John T., and Co., 217 Cedar St., St. Louis, Mo. (Medi- 
cines and pharmaceutical products.) 

Research staff : Edsel A. Ruddiman and 2 assistants. 

Research work : Part time of 3 on medicinal agents. 

314. Milwaukee Coke & Gas Company, The, ist National Bank Build- 
ing, Milwaukee, Wis. 

Research staff: George H. Selke and a number of chemists. 

Research work : Full time of i to increase efficiency of by-product 
coke plant; includes heating of ovens, and recovery of light oil, am- 
monia, gas, etc. 

315. Mineral Refining & Chemical Corporation, Carondelet Station, 
St. Louis, Mo. (Dry paint pigments.) 

Research staff: B. B. McHan and 5 assistants. 

Research work: Approximately one-fourth time of 6 on zinc and 
cadmium hydrometallurgy in its relation to pigment manufacture, and 
the separation and recovery of the impurities ; also barium compounds. 

316. Miner Laboratories, The, 9 S. Clinton St., Chicago, 111. (Con- 
sulting chemists ; pharmaceutical and food problems.) 

Research staff: C. S. Miner, 9 chemists and 2 analysts. 

Research work : Full time of 4 chemists and part time of 3 chemists 
on utilization of oat hulls ; cause of rancidity of vegetable oils ; pre- 
cooked cereals; yeast manufacture; dehydration of potatoes; also 
many research problems are handled as a part of consulting service. 
Supervision of research in molded insulation. 

Equipment : Small scale cereal manufacturing equipment. 
3x7. Minneapolis Steel and Machinery Co.» ^54 Minnehaha Ave., 
Minneapolis, Minn. (Tractors, threshers, structural steel work, 
engines, hoists, etc.) 

Research staff : C. S. Moody, 2 engineers and i assistant engineer, 
3 chemists and 2 assistant chemists; A. W. Scarratt, automotive en- 
gineer, I engineer and 3 assistants. 



54 INDUSTRIAL RESEARCH LABORATORIES 

Research work: One-fourth time of 14 on materials and construc- 
tion. 

Equipment : Izod impact testing machine, ioo,ooa-pound automatic 
autographic Olsen testing machine, Brinell hardness machine, small 
electric furnace for temperature up to 1800 degreee F., Leeds and 
Northrup potentiometer, Leeds and Northrup optical pyrometer, 
metallographical eaumment and Riehle testing machines, Sprague 
dynamometer 100 H. P. at 500 R. P. M. 

3x8. Hojonnier Bros. Co., 739 W. Jackson Boulevard, Chicago, 111. 
(Scientific dairy apparatus and supplies ; milk testing.) 

Research staff : Timothy Mojonnier and J. J. Mojonnier, i analyst, 
3 chemists and 2 chemists and bacteriologists. 

Research work: One-tenth time of 8 on scientific control of milk 
and milk products, particularly in evaporated and condensed plants, 
ice-cream plants and large dairies. Effect of preservatives on com- 
posite milk samples ; culture, propagation, etc. 

Equipment: Mojonnier Model D Milk Tester, containing rapid 
cooling desiccators; the Mojonnier Model E Culture Controller for 
the continual propagation and control of pure lactic cultures; sedi- 
ment tester, acidity and salt tester. 

319. Monroe Drug Company, Color Chemical Division, Bottom Road, 
Quincy, 111. 

Research staff: H. E. Kiefer and 4 assistants. 
Research work: Approximately one-fourth time of 5 on direct 
union colors and intermediates used in their manufacture. 

320. Monsanto Chemical Works, 1800 South 2nd St., St Louis, Mo. 
(Fine and medicinal chemicals, dye intermediates, sulphuric and other 
technical acids, phenol and other heavy chemicals.) 

Research staff: Jules Bebie, 30 chemists, 4 engineers and i safety 
engineer. 

Research work : Full time of 5 or 6 chemists on subjects related to 
synthetic pharmaceuticals and fine chemicals, including intermediates. 

Equipment: Semi-commercial scale experimental laboratory. 
331. Morrill, Geo. H., Co., Norwood, Mass. (Printing and litho- 
graphic inks.) 

Research staff : Olney P. Anthony and 3 chemists. 

Research work : Full time of 4 on ink research. 

Equipment : Dye experimental apparatus. 
322.^ Morris & Company, Union Stock Yards, Chicago, 111. (Packers 
and provisioners.) 

Research staff : J. J. Vollertsen, 3 chemical engineers, i chemist and 
T bacteriologist. 

Research work : Full time of 6 on industrial investigations of pack- 
ing house problems and by-products. 

333. Mulford, H. K., Company, Biological Laboratories, Glenolden, 
Pa. (Manufacturing and biological chemists.) 

Research staff : John Reichel and 9 persons ; in addition, dozens of 
staff and laboratory assistants engage in some research. 

Research work: One-third time of 10 and part time of laboratory 
staff on problems connected with pharmacology, bacteriology, im- 
munology and serology. 



INDUSTRIAL RESEARCH LABORATORIES 55 

Equipment : Specially equipped for dealing with problems relating 
to pharmaceutical, biological, biological agricultural work and chem- 
istry of soil, and for bacteriological and serological work. 

334. Munn, W. Faitoute, 518 Main St., E. Orange, N. J. 
Research staff: W. Faitoute Munn. 

Research work: Nine-tenths time of i on electric furnace, color 
photography and industrial lines in general. 

335. Munmng, A. P., & Co., Matawan, N. J. (Electroplating and 
buffing apparatus and supplies.) 

Research staff : G. A. Cheney, i chemist and i consulting mechan- 
ical and electrical engineer. 

Research work : Approximately one-half time of i on problems in 
connection with the electroplating of metals with the removal of 
grease and dirt from metal surfaces, the polishing of various surfaces 
and the compounds required for such polishes. 

Equipment : Complete apparatus for electroplating. 

336. Musher and Company, Incorporated, Baltimore, Md. Formerly 
The Pompeian Co. 

Research staff : Louis M. Roeg and 2 assistant chemists. 

Research work : Full time of 3 along general lines of food products 
with special attention to expression, care and utilization of vegetable 
oils. 

Equipment: Small scale food manufacturing operations, such as 
expression and filtration of oils. 

337. National Aniline & Chemical Company, Incorporated, 21 Burling 
Slip, New York, N. Y. Research laboratories at Buffalo and Marcus 
Hook, Pa. Dye laboratories at Buffalo and at various sales branches. 

Research staff: G. C. Bailey and 9 chemists at Marcus Hook. 
Varying number of chemists, engineers and other technical men at 
other laboratories. 

Research work : Almost entirely on dyes and intermediates. 

Equipment: Semi-commercial scale equipment for testing pro- 
cesses before putting them on a manufacturing basis. 

338. National Association of Corrugated and Fibre Box Manufac- 
turers, The, 1821 Republic Building, Chicago, 111. 

Research staff: Fred D. Wilson and i assistant. 

Research work : Full time of i on designing and testing corrugated 
and solid fibre containers to develop the best container for the com- 
modity experimented with. 

Equipment : Revolving testing drum for fibre boxes. 

339. National Biscuit Company, 409 W. Fifteenth St., New York, 
N. Y. Formerly Marvin-Davis Laboratories, Incorporated. 

Research staff: Clarke E. Davis, 4 chemists, i engineer, i baker 
and I assistant. 

Research work : Full time of 8 on food products, their packing and 
distribution. 

National Board of Fire Underwriters. See Underwriters' Lab- 
oratories (p. 77). 

330. National Canners Association, 1739 H St. N. W., Washington, 
D. C. 

Research staff: W. D. Bigelow, 4 chemists and 3 bacteriologists. 



j 



56 INDUSTRIAL RESEARCH LABORATORIES 

Research work : Full time of i and part time of i on study of tin 
plate from all standpoints ; causes of pinholing in tin cans ; influence 
of composition and details of manufacture of steel on service value of 
tin plate. Full time of i on study of heat penetration of canned food ; 
study of various factors affecting penetration of heat to the center of 
the can ; distribution of heat in sterilizing kettles in different systems 
of management. Full time of 3 on study of microorganisms causing 
spoilage; isolation of spoilage bacteria and study of their cultural 
characteristics with special reference to thermal death point; study 
of habitat of spoilage organisms in canning plants and farms where 
raw products are grown. Full time of i and part time of i on study 
of minor miscellaneous technological qeustions arisinp; from time to 
time. Some of the most effective work has been done m collaboration 
with other organizations. For instance, the tin plate investigations 
are conducted in collaboration with manufacturers of steel, tin plate, 
and cans. 

Equipment: Special canning equipment with laboratory facilities. 
Experimental small factory scale cannery and canning laboratory. 

National Carbon Company. See Union Carbide and Carbon Re- 
search Laboratories, Inc. (p. 78). 
331. National Cash Register Company, The, Dayton, Ohio. 

Research staff: A. B. Beaver, 12 chemists, 3 electrical engineers, 
6 mechanical engineers and 2 metallurgists. 

Research work: Full time of 8 and approximately one-tenth time 
of others on chemical, mechanical, electrical, metallurgical and manu- 
facturing problems. 

Equipment: Special equipment for conducting endurance tests on 
cash registers. 

33a. National Cereal Products Laboratories, 1731 H St. N. W., Wash- 
ington, D. C. (Chemical and technical advisors for The National 
Macaroni Manufacturers' Association and The Alimentary Paste 
Manufacturers' Association.) 

Research staff: B. R. Jacobs and i chemist. 

Research work : One-fourth time of 2 on standardization of cereal 
products and raw materials entering into their composition, methods 
of control in purchasing raw materials and containers for cereal 
products. 

333. National Gum & Mica Co., 12 West End Ave., New York, N. Y. 
Research staff: S. Ginsburg, chemist, A. A. Haldenstein, chemical 

engineer, and 3 assistants. 

Research work : Four-fifths time of 5 on adhesives, colloids, gums, 
starches, colors, sizings, finishings, etc., for paper and textiles. 

334. National Laboratories, The, 1313 H St. N. W., Washington, 
D. C. 

Research staff : Ivan S. Hocker, 2 chemical engineers, i mechanical 
engineer, 2 chemists, and i bacteriologist. 

Research work : Gelatine, bacteriological dyes, by-products in acid 
industries, yeast and fermentation problems, malt extracts and bread 
improvers, glass, flotation oils and paints, cellulose and paper. 
335-339« National Lamp Works of General Electric Company, Nda 
Park, Cleveland, Ohio. Research Department: Edward P. Hyde, 



INDUSTRIAL RESEARCH LABORATORIES 57 

director of research, Francis E. Cady, manager, and J others. Instru- 
ment shop, power plant, lamp shop and library. Renders service to 
other research and development laboratories. 

335. Nela Research Laboratories 
Laboratory of Pure Science 

Research staff: Directorship vacant; 3 physicists, i physical- 
chemist, I psychologist, 2 biologists, 5 laboratory assistants, i student 
on Brush Fellowship. 

Research work: Full time of 13 on the physics, physiology, and 
psychology of light, particularly in those phases which pertain to the 
science of illumination ; the production of luminous energy ; the laws 
of radiation ; and the effects of luminous and attendant radiation, par- 
ticularly in connection with its physiological, psychological, biologi- 
cal, and chemical action. Records of researches are presented before 
scientific and technical societies and are published as contributions to 
the technical journals. 

Laboratory of Applied Science 

Research staff: M. Luckiesh, 3 physicists, i engineer-physicist, 2 
assistant physicists, i architect-engineer, i architect-designer, i light- 
ing assistant, 4 laboratory assistants, 2 clerical workers. 

Research work: Full time of 14 on spectrum analysis; light-pro- 
duction ; spectrophotometry ; photometry ; various physical properties 
and measurements pertaining to glass, metals, etc. ; physical, biolog- 
ical, physiological, photo-chemical, and psychological aspects of light 
utilization ; various phases of color. 

336. Lamp Development Laboratory 

Research staff: J. E. Randall, consulting engineer, W. L. Enfield, 
manager, and I9 men. 

Research work: Full time of 21 on development of processes of 
manufacture of incandescent lamps ; investigation of quality of prod- 
uct ; design of lamps ; development of new types of lamps ; investiga- 
tions of raw materials for use in manufacture of lamps ; development 
work on tungsten wire. 

Equipment: Special equipment for use in lamp manufacture built 
by National Lamp Works shop. 

337. Experimental Engineering Laboratory 
Research staff: Frank M. Dorsey and 33 assistants. 
Research work : One-half time of 34 on a variety of problems. 
Equipment: Adequate facilities for large-scale experiments, 

whether on lamp making or chemical and metallurgical processes. 

338. Glass Technology Department 

Research staff: Wm. M. Clark, 7 technical men and 3 experienced 
practical glassmen. 

Research work : One-half time of 4 on development work on glass 
parts used in connection with the manufacture of incandescent lamps. 

Equipment: High temperature furnace equipment both gas and 
electrically heated. Physical and optical apparatus for determining 
the physical and optical properties of different glasses. 

339. Engineering Department 

Research staff: S. E. Doane, chief engineer, and 57 electrical 
engineering graduates. 



58 INDUSTRIAL RESEARCH LABORATORIES 

Research work: One-half time of 15 on determining performance 
and characteristic data on incandescent lamps and lamp accessories; 
study of economics of light production; study of methods of light 
utilization from standpoint of obtaining most satisfactory illumination 
results. 
340. National Lead Company. 129 York Street, Brooklyn, N. Y. 

Research staff: Gustave W. Thompson, 3 assistants, 7 special in- 
vestigators and analysts, 2 paint experts, i colorist, and necessary 
assistants. 

Research work: Large part of time of 34 on investigations con- 
nected with manufacture and utilization of lead products (white lead, 
lead oxides, alloys, etc.), other paint pigments, linseed oil and other 
paint vehicles, paint technology, metallurgy of lead and of tin, physical 
testing and metallography of white metal alloys, microphotography, 
etc. 

Equipment: Apparatus for testing of pigments, oils and metals, 
including special apparatus for measuring whiteness of pigments; 
opacity of paint films; fineness of pigments by classification; How- 
land color photometer ; tension and hardness testing machines. 
34Z. National Lime Association, 918 G St. N. W., Washington, D. C. 

Research staff: M. E. Holmes, E. O. Pippin and 2 assistants. In 
addition to the resident staff, there are 5 others in university and gov- 
ernment laboratories working on fellowships. 

Research work: Full time of 3 on properties and uses of lime in 
the chemical, agricultural and construction fields. 
34a. National Malleable Castings Company, The, 10600 Quincey 
Ave., Cleveland, Ohio. 

Research staff : H. A. Schwartz, 3 metallographers and chemists, i 
physicist, i tester of materials and 3 assistants. 

Research work: Full time of 9 on properties of ferrous alloys, 
especially fatigue, alternating and impact stresses and resistance to 
cutting; equilibrium conditions in non-carbon alloys, particularly in 
stable system ; miscellaneous metallurgical investigations. 

Equipment : One 50,000-pound for 6-foot specimens, and one 200,- 
000-pound Olsen 3-screw testing machine; 00,000-inch-pound Olsen 
torsion machine; Olsen universal efficiency testing machine; Charpy 
impact machine ; Brinell machine, scleroscope ; inverted type Bausch & 
Lomb metallographic microscope; automatic and autographic appa- 
ratus for precision heat treatment of metals. 

National Stain and Reagent Co. See Coleman & Bell Company, 
The (p. 20). 

343. National Tube Company, Frick Building, Pittsburgh, Pa. (Steel 
and iron tubes and pipes.) 

Research staff : F. N. Speller and 6 to 8 men. 

Research work: Full time of staff on metallurgical and chemical 
research work as applied to mill operations and various uses of tubular 
material by consumers. Considerable portion of time devoted to the 
problem of corrosion and protection of iron and steel from corrosion. 

344. Naugatuck Chemical Company, The, Naugatuck, Conn. 
Research staff: H. S. Adams, 3 chemists and 5 assistants. 



INDUSTRIAL RESEARCH LABORATORIES 59 

Research work : Full time of 9 on chemicals pertaining to the rub- 
ber industry. 

Nela Research Laboratories. See National Lamp Works of 
General Electric Company (p. 56). 

345. Nestli's Food Company, Incorporated, 130 William St., New 
York, N. Y. (Condensed milk.) Laboratory also at Ithaca, N. Y. 

Research staff: A. A. Scott, i bacteriologist and micologist and i 
assistant ; 2 chemists and 2 assistants. F. E. Rice and i assistant at 
Ithaca laboratory. 

Research work : Full time of 3 on sweetened condensed and evap- 
orated milk and other products that the company produces or may 
produce. 

Equipment : Experimental equipment for production of condensed 
and evaporated milk. 

346. Newark Industrial Laboratories, 96 Academy St., Newark, N. J. 
(Conduct researches on an experimental as well as on a semi-com- 
mercial scale.) 

Research staff: Hubert Grunenberg and 3 assistant collegiate 
chemists. 

Research work: Development of synthetic flavoring matters, per- 
fumes, drugs, and dyes. 

347. New England Confectionery Company, 253 Summer St., Boston, 
Mass. 

Research staff : Edmund Clark and i chemist. 
Research work : Nine-tenths time of 2 on problems connected with 
the industry. 

348. New Jersey Zinc Company, The, 160 Front St., New York, N. Y. 
Research staff : J. A. Singmaster, manager of technical department, 

F. G. Breyer, chief research division, 14 chemists, 8 physicists and 12 
assistants. 

Research work : Full time of 34 on mechanical and physical inves- 
tigations connected wth metallurgy of zinc ; manufacture and use^ of 
zinc oxide in rubber and paint industries ; manufacture and utilization 
of sulphuric acid ; production and properties of worked metallic zinc 
in shapes of strips, sheets, etc. 

349. Newport Company, The, Pensacola, Fla. 
Research staff : R. C. Palmer and 2 assistants. 

Research work : Whole time of i and one-quarter time of 2 on prob- 
lems relating to the technical and industrial development of terpenes 
and terpene products, rosins and rosin products. 

Newport Turpentine & Rosin Company of Florida. See New- 
port Company, The. 

350. New York Quebracho Extract Company, Incorporated, 80 
Maiden Lane, New York, N. Y. 

Laboratory at Greene and West Sts., Greenpoint, Brooklyn, N. Y. 

Research staff : R. O. Phillips and 4 chemists. 

Research work: One-half time of 5 on tannery operation, extract 
manufacture and various problems in connection with the manufacture 
and testing of leather. 

Equipment: Experimental tannery. 



60 INDUSTRIAL RESEARCH LABORATORIES 

351. New York Quinine & Chemical Works, Incorporated, The, 135 

William St., New York, N. Y. 

Research staff : George L. Schaef er, 7 chemists and 2 engineers. 

Research work: Approximately one-half time of 7 chemists on 
organic products, alkaloids, and medicinal chemicals. 
35a. New York Sugar Trade Laboratory, Inc., The, 79 Wall St., New 
York, N. Y. 

Research staff : C. A. Browne, S chemists and i helper. 

Research work : One-fourth time of 7 on composition and deteriora- 
tion of sugars; optical and chemical methods of sugar analysis; 
influence of temperature and other conditions on polarization of 
sugars ; composition and food value of syrups and molasses. 

Equipment: Constant temperature laboratory for polarization of 
sugars. 

353. Niles Tool Works Company, The, 545 North Third St., Hamil- 
ton, Ohio. (Machine tools.) 

Research staff: J. W. Bolton, i experimental engineer, 2 routine 
men and labor as desired. 

Research work: One-fourth to three-fourths time of 4 on metal- 
lurgy of grey iron, especially practical applications of metallography, 
studies of changes produced by pouring temperatures, section size, 
etc. Heat treatment, brass and bronze, core oils, etc. 

Equipment : Completely equipped laboratory for study of grey iron. 
354* Northwestern Chemical Co., The, Marietta, Ohio. (Chemical 
automobile utilities.) 

Research staff: A. S. Isaacs and 2 advisors. 

Research work : One-half time of i on problems incident to auto- 
mobile trade and news ink trade; cements, polishes, dressings and 
enamels, printers' ink, oil and carbon black. 

355. Norvell Chemical Corporation, The, 1 1 Cliff St., New York, N. Y. 
Research staff: 4 chemists. 

Research work : One-fourth time of 4 on mercurial products, phos- 
phates, benzoate group, wood distillation derivatives, formaldehyde 
condensation products, citric and oxalic acid derivatives, aniline de- 
rivatives, phosgene condensation products and other pharmaceutical 
and technical products. 

356. Nowajc Chemical Laboratories, 518 Chemical Building, St. Louis, 
Mo. 

Research staff: C. A. Nowak. 

Research work : On flavoring extracts used in soft drink manufac- 
ture. 

Equipment: Well equipped for brewery and other beverage and 
food work. 

357. Nulomoline Company, The, 11 1 Wall St., New York, N. Y. 
(Glycerine substitutes.) 

Research staff: M. A. Schneller, i chemist, i confectionery engi- 
neer and I laboratory assistant. 

Research work: Approximately one-half time of 3 on sugar and 
sugar products. 

358. Ohio Fuel Supply Company, The, 99 N. Front St., Columbus, 
Ohio. Laboratory at Utica, Ohio. 



INDUSTRIAL RESEARCH LABORATORIES 61 

Research staff: George T. Koch, 2 chemists, 2 chemical engineers 
and 2 routine men. 

Research work: Approximately three-fourths time of 5 on petro- 
leum, natural gas, gasoline, particularly the manufacture of synthetic 
chemicals, such as amyl acetate, formaldehyde, formic acid, etc., from 
the above natural products and absorption processes for gasoline. 

359. Ohio Grease Co., The, Londonville, Ohio. (Lubricants.) 
Research staff: i chemist. 

Research work: Analysis of oils, fats and greases, such as are re- 
quired in a grease factory. 

360. Oliver Continuous Filter Co., 503 Market St., San Francisco, 
Calif. Laboratories also at 226 E. 41st St., New York, N. Y., and 
No. 9 Red Lion Passage, Holborn, London, W. C. I., England. 

Research staff: E. L. Oliver in San Francisco, R. Gordon Walker 
in New York and J. F. Mitchell-Roberts in London, with 3 engineers 
and I chemist available for each laboratory. 

Research work: Investigation of methods for increasing efficiencv 
and reducing costs of filtration of all classes of chemical and metal- 
lurgical products. No work done on drinking water filtration. Prin- 
cipal products investigated are beet and cane sugar juices and saccha- 
rate of lime ; lime sludges ; wood pulp ; sewage ; phosphoric acid ; cy- 
anide slimes ; flotation concentrate ; clays of all kinds ; dyes, etc. 

Equipment : Continuous vacuum filters, small intermittent vacuum 
filters, various devices for treating filter "cake" during the filter cycle 
to reduce moisture or increase washing- efficiency. 

Orford Copper Co., The. See International Nickel Company, 
The (p. 44). 

361. Package Paper and Supply Corporation, 150 Birnie Ave., Spring- 
field, Mass. (Waxed papers.) 

Research staff: W. M. Bovard, 2 chemists, i engineer and i as- 
sistant. 

Research work : Approximately three-tenths time of S on wrapping 
food products, especially for moisture protection, specializing on 
waxed paper for automatic wrapping machine for wrapping soap, 
cereals, food products and candy and developing special papers. 
363. Packard Motor Car Company, Detroit, Mich. Engineering 
laboratory. 

Research staff : L. M. Woolson, 3 engineers and i chemist. 

Research work : Full time of 5 on problems connected with' Liberty 
motor, motor trucks and automobiles; automobile and truck chassis 
development. 

Equipment: Complete dynamometer equipment for testing truck, 
car and airplane engines up to 500 H. P. Complete bench testing 
equipment for all car, truck and airplane accessories. Automotive 
power plant and accessories. 

Page, Carl H. See Riverbank Laboratories (p. 68). 
363. Palatine Aniline and Chemical Corporation, 81 N. Water St., 
Poughkeepsie, N. Y. (Dyestuffs and chemicals.) 

Research staff: Felix Braude and 2 chemists. 

Research work : Full time of 3 on intermediates and dyestuffs. 



62 INDUSTRIAL RESEARCH LABORATORIES 

364. Palmolive Company, The, Milwaukee, Wis. 
Research staff: V. K. Cassady and 7 assistants. 

Research work : Full time of i and approximately one-fourth time 
of 6 on soaps and perfumes. 

365. Pantasote Leather Company, The, Passaic, N. J. 
Research staff: Edgar Josephson. 

Research work : Full time of i on coatings for textiles, rubber coat- 
ings for fabrics, oils, paints, varnishes and all closely related indus- 
tries. 

366. Parke, Davis & Company, Detroit, Mich. (Medicinal prepara- 
tions.) 

Research staff: J. M. Francis, chief chemist, Oliver Kamm, chief 
of chemical research department, E. M. Houghton, chief of medical 
research department and about 40 chemists, pharmacists, bacteriolo- 
gists, botanists and pharmacologists. 

Research work : Large part time of about 20 is devoted to the im- 
provement in the constitution, or processes of manufacture, of sub- 
stances now used as medicaments; and in the attempt to discover or 
produce new therapeutic agents in both pharmaceutical and biologic 
lines. 

Patton Paint Company. See Pittsburgh Plate Glass Co. (p. 65). 

367. Pea3e Laboratories, 39 West 38th St., New York, N. Y. (Suc- 
cessors to Lederle Laboratories.) 

Research staff : H. D. Pease and a number of chemists, bacteriolo- 
gists and assistants. 

Research work: Small part time of staff along sanitary, chemical 
and bacteriological lines. 

368. Peerless Color Company, Bound Brook, N. J. 
Research staff: R. W. Comelison and 2 chemists. 

Research work: Part time of 3 on problems dealing directly with 
the manufacture of dyestuffs. 

369. Peerless Drawn Steel Company, The, Massillon, Ohio. 
Research staff: A. M. LeTellier and 4 assistants. 

Research work : Approximately one-half time of 5 on effect of heat 
treating and cold drawing on all grades of steel and development of 
the cold drawing of steel. 

Equipment: Apparatus for studying chemical and physical prop- 
erties of steel, including full heat treating department as well as 
metallography department. 
369a. Peet Bros. Mfg. Co., Kansas City, Kans. 

Research staff: W. J. Reese and 2 assistants. 

Research work: Problems connected with the manufacture of 
soaps and glycerin. 

370. Penick & Ford, Ltd., Incorporated, New Orleans, La. (Sugar, 
cane and corn products.) Laboratory at Marrero, La. 

Research staff: F. W. Zerban, i chemist, i assistant chemist and 
assistants. 

Research work : Full time of 3 or more on manufacture and refin- 
ing of the products of sugar cane, corn and other saccharine plants. 

371. Pennsylvania Railroad Company, The, Altoona, Pa. 
Research work: Small part time of staff on investigation of cause 

of failure of steel rails ; locomotive design ; much work in preparation 
of specifications for various materials; general field of lubrication; 



INDUSTRIAL RESEARCH LABORATORIES 63 

water treatment and purification ; paints and preservatives ; heat treat- 
ment of metals, etc. Investigation of electrolysis in systems of under- 
ground metallic structures; tests and investigations of the construc- 
tion of various makes of transformers ; tests of various makes of pri- 
mary and secondary battery cells; oscillo^aphic tests for linear and 
angular velocity, wave forms, etc.; investigations of special cases of 
electrical troubles ; development of an electrical method of measuring 
the hardness and homogeneity of steel. Tests of locomotives on the 
road or tests of equipment with special devices; tonnage rating of 
trains and following up of all experimental appliances which are put 
into service for test purposes. Methods for determination of elements 
in plain-carbon steels, alloy steels and non-ferrous alloys used for 
bearing backs and linings, packing-ring metal for different purposes, 
etc. Examination of fuels, development of specifications for paint 
products, lubricating and burning oils, boiler compounds, lacquers, 
plush, car cleaners, cutting compounds, belt dressing, polishing com- 
pounds, hydraulic- jack liquids, fuses, track caps, fire-extinguishing 
preparations, the recovery of used or wasted products, etc. 

Equipment: Six universal tension and compression testing ma- 
chines, one of 1,000,000, two of 300,000, two of 100,000-pound and one 
of iso,ooo-pound capacity; one vibratory endurance spring testing 
machine of 75,000-pound capacity; one 43-foot and one 57-foot drop- 
testing machine ; two vibrating staybolt testing machines ; one Brinell 
hardness testing machine; one 2000-pound cement testing machine; 
metallographic equipment. 

Apparatus for testing hose: Six rubber stretching machines; one 
friction test rack for rubber ; one hose mounting machine ; one vibrat- 
ing test rack for hose; one continuous test rack for rubber; four ten- 
sion testing machines for rubber ; one stretching machine for rubber 
insulation ; one spring micrometer machine ; one vacuum gage testing 
machine ; one arbor press specimen cutter ; one hydraulic gage testing 
machine, capacity 25,000 pounds per square inch; one dead-weight 
gage testing machine, capacity six gages; one wiggling testing ma- 
chine for hose ; one bumping testing machine for gages ; one whipping 
testing machine for g^ges; one hydraulic machine for testing gage 
glasses. 

Rubber, air-brake hose and miscellaneous laboratory, machines for 
air-brake, signal and tank hose, and other miscellaneous tests. 

Electrical laboratory, equipment for lamp tests consisting of three 
photometers, lamp test rack of 1000 lamps capacity, with switchboard, 
transformers and potential regulator equipment. 

372. Pennsylvania Salt Manufacturing Co., Philadelphia, Pa. 
Research staff: Director, chief chemist and 3 assistant chemists. 
Research work: Problems relating to the manufacture of heavy 

chemicals. 

373. Permutit Company, The, 440 Fourth Ave., New York, N. Y. 
(Water rectification systems.) Factory at Brooklyn, N. Y. 

Research staff : T. R. Duggan, 7 chemists and 4 chemical engineers. 
Research work: Full time of 3 entirely in connection with water 
problems and the use and manufacture of artificial zeolites. 



64 INDUSTRIAL RESEARCH LABORATORIES 

374. Perolin Company of America, The, 2010 Peoples Gas Bldg., Chi- 
cago, 111. Laboratory at 11 12 W. 37th St., Chicago, 111. 

Research staff : E. L. Gross, chemical engineer. 
Research work : Protection of metal surfaces against rust and pit- 
ting and boiler scale removal and prevention. 
Equipment : Beach-Russ vacuum pump and copper retorts. 

375. Pettee, Charles L. W., Laboratories of, 112 High St., Hartford, 
Conn. (Analytical and consulting chemist.) 

Research staff: C. L. W. Pettee and i chemist. 
Research work : Three-twentieths time of 2 on recovery and puri- 
fication of precious metals. 

376. Pfaudler Co., The, Rochester, N. Y. 

Research staff: O. I. Chormann, i chemist, i metallurgist and i 
helper. 

Research work: Three-fourths time of 3 on enamels for steel and 
cast iron ; packings ; resistivity of enamels, etc. 

377. Pfister ft Vogel Leather Co., 447 Virginia St., Milwaukee, Wis. 
(Tanners and curriers.) 

Research staff: Louis E. Levi, 2 research chemists and 7 other 
chemists. 

Research work : Full time of 4 on problems related to leather, glue, 
hair, gelatine, retarder, bitumen, paints, etc. 

378. Pfizer, Chas., ft Co., Inc., 81 Maiden Lane, New York, N. Y. 
(Manufacturing chemists.) Laboratory at 11 Bartlett St., Brooklyn, 
N. Y. 

Research staff: Richard Pastemack, 5 chemists and chemical engi- 
neers and I engineer. 

Research work: Full time of 7 on development of processes and 
products. 

Equipment: Complete laboratory and semi-plant equipment. 
379* Pharma-Chemical Corporation, 1570 Wool worth Bldg., New 
York, N. Y. Laboratory at Bayonne, N. J. 

Research staff : Eugene A. Markush, 3 chemists and i engineer. 

Research work: Dyes and pharmaceuticals. 

380. Philadelphia Quartz Company, Philadelphia, Pa. (Silicate of 
soda.) 

Research' staff : James G. Vail, 4 chemists and i assistant. 

Research work : One-half time of 6 on problems involving applica- 
tion or manufacture of silicate of soda, study of its properties as an 
adhesive, as an ingredient of acid-proof cement, grinding wheels, soap, 
asbestos insulating material, coating materials for paper and wooden 
packages, to prevent the absorption of grease, as an agent in refining 
of vegetable oils, etc. 

Equipment : Crushing and grinding apparatus, two gas-heated fur- 
naces for experiments with fusion, one a small open hearth, and the 
other a crucible furnace; apparatus for fusion, testing of adhesives, 
cement, etc., and devices for making the usual commercial tests on 
paper; small and semi-commercial autoclaves. 

381. Ph]r8icians and Surgeons Laboratory, 605 Paxton Blk., Omaha, 
Nebr. 



INDUSTRIAL RESEARCH LABORATORIES 65 

Research staff: Theodore M. Agnew, i chemist, i bacteriologist 
and I pathologist and serologist. 

Research work : . Variable amount time of 4 on bacteriological, path- 
ological and serological problems. 

382. Pierce-Arrow Motor Car Company, The» Elmwood Ave., Buffalo, 
N. Y. 

Research staff : J. Miller, metallurgist, and 2 assistants ; W. Slaght, 
experimental engineer and 2 assistants. 

Research work: Approximately one-fourth time of 8 on cause of 
failure of parts, effect of impurities in metals, heat treatment, effect 
of shocks, alternate stresses and efKciency of engines and transmis- 
sions. 

Equipment : Olsen testing machine, Avery impact testing machine, 
Stanton impact testing machine, 150 H. P. electric dynameter and 
engine test stand. 

Pitcaim Varnish Co. See Pittsburgh Plate Glass Co. 
383-384. Pittsburgh Plate Glass Co., Milwaukee, Wis. Laboratory 
also at Newark, N. J. 

383. Paiton-Pitcaim Division (Patton Paint Company and Pitcaim 
Varnish Company). 

Research staff: A. H. Woltersdorf and assistants at Milwaukee; 
T. R. Collins and 2 assistants at Newark. 

Research work : Part time of staff on problems connected with the 
paint and varnish industry. 

384. Corona Chemical Division (Corona Chemical Company). 
Research staff: C. B. Dickey and assistants. 

385. Pittsburgh Testing Laboratory, 616 Grant St., Pittsburgh, Pa. 
Laboratories also in New York, N. Y., Birmingham, Ala., and Cin- 
cinnati, Ohio. 

* Research staff : Jas. O. Handy, director of special investigations, 
H. H. Craver, manager chemical department, 26 chemists in Pitts- 
burgh, 2 in New York, 3 in Birmingham and i in Cincinnati ; 3 me- 
chanical and 3 civil en^^neers. 

Research work : Variable amount of time of staff on food and drugs 
(alcohol substitutes, etc.), oil refining (lubricating oil recovery), cor- 
rosion-resisting metals, water purification, metal extraction from ores 
and refractory materials (basic). 

Equipment: Furnaces, special metallographic equipment, coal dis- 
tillation apparatus (to be installed) and testing machines. 

Pompeian Co., The. See Musher and Company, Incorporated 

(p. 55)- 

386. Porro Biological Laboratories, 625 Puget Sound Bank Bldg., 
Tacoma, Wash. (Successors to Staniford Laboratories.) 

Research staff : Thomas J. Porro and John G. Scott. 
Research work: Part time of 2 on chemical, serological and bac- 
teriological problems. 

387. Portage Rubber Co., The, Barberton, Ohio. 
Research staff: R. M. Gage and 2 chemists. 

Research work : One-half time of 3 on testing and compounding for 
rubber goods. 



66 INDUSTRIAL RESEARCH LABORATORIES 

388. Porter, Horace C, 1833 Chestnut St., Philadelphia, Pa. (Con- 
sulting chemist and chemical engineer.) 

Research staff : Horace C. Porter and i assistant. 

Research work : Coal carbonization, coking and by-products, "low 
temperature" carbonization, shale distillation, application of fuels, re- 
duction of wastes, coal storage problems and spontaneous combustion. 

Equipment: Coal distillation retort (laboratory scale) and acces- 
sories. 

389. Powers-Weightman-Rosengarten Company, The, 916 Parrish 
St., Philadelphia, Pa. (Chemists.) 

Research staff: George D. Rosengarten and varying number of 
assistants. 

Research work : Variable amount time of staff on improvement of 
present processes and investigation of new processes. 

Prest-O-Lite Co., Inc., The. See Union Carbide and Carbon 
Research Laboratories, Inc. (p. 78). 

390. Procter & Gamble Co., The, Cincinnati, Ohio. (Soaps, glyce- 
rine, candles, lard substitutes, refined oils, etc.) Laboratory at Ivory- 
dale, Ohio. 

Research staff: H. J. Morrison and 12 chemists. 

Research work : Improvement of plant processes and products. 

Equipment: Complete experimental plants for the various pro- 
cesses. 

39Z. Providence Gas Company, Incorporated, Providence, R. I. 
Manufacturing Department. 

Research staff: A. H. Meyer, i assistant chemist and 2 minor 
chemists. 

Research work: Small part time of 4 on problems arising in 
manufacture. 

Equipment : Laboratory is complete for gas plant operation. 
39a. Pure Oil Company, Kanawha River Salt and Chemical Division, 
Charleston, W. Va. Laboratory at Belle, W. Va. 

Research staff : W. A. Borror and i chemist. 

Research work : One-half time of i on salt industry, salt brine and 
development of processes. 

393. Pure Oil Company, Moore Oil and Refining Company Division, 
York and McLean Aves., Cincinnati, Ohio. 

Research staff : Frank Groodale and 2 assistants. 
Research work: Full time of 3 on soaps, greases, polishes, lubri- 
cating and soluble oils ; textile, boiler and cutting compounds. 

394. Pyrolectric Instrument Company, 636 E. State St., Trenton, N. J. 
(Pyrometric and electrical precision instruments.) 

Research staff: H. L. Saums, i chemist, i electrical engineer and 
I mechanical engineer. 

Research work: Approximately one-fourth time of 4 on construc- 
tion and adaptations of electrical instruments; special problems re- 
quiring combination of mechanical and electrical development; tem- 
perature measurement problems, problems in hydrogen-ion determi- 
nations. 

395. Pjrro-Non Paint Co., Inc., 505 Driggs Ave., Brooklyn, N. Y. 
(Fire retarding paints and products.) 



INDUSTRIAL RESEARCH LABORATORIES 67 

Research staff : Ernest A. Marx, i chemical engineer and i chemist. 
Research work: One-half time of 3 on technical paints and paint 
products. 

Equipment : Inflammability test apparatus. 

396. Quinn, T. H., ft Comi>any» which includes: Lackawanna, Sus- 
quehanna, Vandalia, Tonesta Valley, Keystone, Heinemann, Barclay, 
Beerston Acetate Co., Smethport Chemical Companies and the Quinn 
Laboratories Company. General office at Olean, N. Y. Laboratory 
at E. Smethport, Pa. 

Research staff: Edward E. Currier, 3 chemists, i engineer and 
occasional assistance from other specialists. 

Research work: Approximately one-third time of 5 on researches 
on gases from wood, researches on the phenolic constituents of wood 
oils and tars, formaldehyde and physical properties of charcoals. 

Equipment : Destructive distillation plant and formaldehyde plant, 
both on small scale. 

397. Radiant Dye ft Color Works, 2837 W. 21st St., Brooklyn, N. Y. 
Research staff: William Goldstein and i chemist. 

Research work : Full time of 2 on triphenylmethane dyes and their 
derivatives. 

398. Radium Company of Colorado, Inc., The, i8th and Blake Sts., 
Denver, Colo. 

Research staff: W. A. Schlesinger, 12 chemists and 4 engineers. 

Research work: Approximately one-fifth time of 17 on radium, 
uranium and vanadium. 

399- Radium Limited, U. S. A., 2 W. 45th St., New York, N. Y. 
(Radium emanation activators, radium ore, apparatus, etc.) 

Research staff : Henry H. Singer, i chemist and 2 assistants. 

Research work : One-half time of 4 on radium ore, radium, radium 
emanation, radium luminous material and all other matters affiliated 
with radium and similar products. 

Equipment : Electrometers, fontactoscopes, spinthariscopes, ex- 
perimental and demonstration outfits and exhibition of rare earth and 
all kinds of luminous materials and paints.) 
400. Ransom & Randolph Co., The, 518 Jefferson Ave., Toledo, Ohio. 

Research staff : Thomas E. Moore, i chemist, i mechanical engineer 
and 2 dentists. 

Research work : Three-fourths time of 5 on dental materials. 
40Z. Raritan Copper Works, Perth Amboy, N. J. Research Depart- 
ment. 

Research staff: S. Skowronski, 3 chemists and i physicist. 

Research work: Full time of 5 on copper metallurgy, electrolytic 
refining of copper, and recovery of by-products, gold, silver, platinum, 
palladium, selenium, tellurium, arsenic, nickel, antimony. 

402. Redlands Fruit Products Company, Redlands, Calif. 
Research staff: H. P. D. Kingsbury and i chemist. 

Research work : Small part time of 2 on fruit products, for example, 
bottling orange juice. 

403. Redmanol Chemical Products Co., 636 W. 22nd St., Chicago, 111. 
(Acid- and heat-proof varnishes and lacquers, synthetic amber, mould- 
ing compounds ; for electrical insulation and other uses.) 



I» INDUSTRIAL RESEARCH LABORATORIES 

Research staff: L. V. Redman, A. J. Wcith and F. P. Brock; 8 
chemists and 6 chemical engineers. 

Research work : Full time of 6 on electrical insulation from phenol, 
condensation products and synthetic amber*like resins. 

Equipment: Vacuum apparatus, rubber mixing rolls, beater mills, 
kneading machines, hydraulic presses, stills, dephlegmators and higti 
temperature kilns. 

404. Reliance Aniline ft Chemical Co.» Incorporated, Poughkeepsie, 
N. Y. 

Research staff : Philip Kaplan and i chemist. 

Research work : One-third time of 2 along lines of synthetic dyes. 

405. Remington Arms, Union Metallic Cartridge Company, Bamum 
Ave., Bridgeport, Conn. Research Division. 

Research staff : 3 chemists, 3 assistant chemists, i metallographist, 
I assistant metallographist and pyrometer expert, 2 engineers and 7 
raicellaneous. 

Rjcsearch work: One-eighth time of 15 on small arms ammunition. 

406. Research Corporation, 25 W. 43rd St., New York, N. Y. Labora- 
tory at St. Pauls Ave., Jersey City, N. J. 

Research work: Problems of converting a work of completed re- 
search to commercial or industrial application and use. 

Equipment: Apparatus for developing the Cottrell electrical pre- 
cipitation processes. 

407. Rhode Island MaUeable Iron Works, Hillsgrove, R. I. 
Research staff: M. M. Marcus, i chemist and i engineer. 
Research work : Part time of 3 on furnace practice and testing. 
Equipment : Commercial air furnaces, annealing furnaces and core 

ovens. 

408. Richards ft Locke, 69 Massachusetts Ave., Cambridge 39, Mass. 
(Mining engineers.) 

Research staff: Robert H. Richards and Charles E. Locke with 
from I to 3 or 4 engineers and chemists. 

Research work: Approximately full time on commercial problems 
of ore concentration and allied subjects. 

Equipment : Full ore testing equipment. 

409. Richardson Company, The, Lockland, Ohio. Heppes Roofing 
Division and laboratory at. 26th and Lake Sts., Melrose Park, 111. 

Research staff : Robert Holz and 4 chemists. 

Research work: One-half time on manufacture of asphalt and 
roofing products. 

4x0. Riches, Piver ft Co., 30 Church St., New York, N. Y. (Chemical 
and color manufacturers and importers.) Laboratory at Hillside, 
Elizabeth, N. J. 

Research work : Insecticides, fungicides and the raw materials from 
which they may be made. 

411. Riverbank Laboratories, Geneva, 111. (Commercial research and 
experimental laboratories.) 

Research staff: Carl M. Page, several chemists, physicists and 
other assistants. 

Research work: Full time of director and part time of others on 
physical, chemical and metallurgical problems ; rubber. 



INDUSTRIAL RESEARCH LABORATORIES 69 

Equipment: Apparatus for work on phenomena of high-potential 
discharges and vacuum tubes; includes i6-plate static machine 36- 
inch diameter, one 18-inch and one lo-inch spark X-ray coils with 
electrolytic and mercury turbine interrupters, one 20,000-volt alter- 
nating current transformer with rotary converter, vacuum tube oven, 
assortment of special tubes, Gaede mercurial air-pump for high 
vacuum with a Geryk oil-pump as auxiliary. Large special arc lamps 
for ultra-violet rays ; apparatus for work in molecular transformations 
of hydrocarbon oils; turbine-driven Sharpless super-centrifuge, with 
many accessories of own design ; small shop for making special appa- 
ratus. 
4za. Rochester Button Company, 300 State St., Rochester, N. Y. 

Research staff : J. F. Clark, i chemist, 2 engineers, i designer and 
2 assistants. 

Research work : Full time of 7 on investigation of plant processes, 
materials and machinery used in manufacturing buttons. 

413. Rodman Chemical Company, Verona, Pa. (Case hardening and 
carbonizing compounds.) 

Research staff : Hugh Rodman and 2 assistants. 

Research work: Approximately full time of 3 on carburizing of 
steel, investigation of carbonizing agents, special coking systems, 
activated carbon and general research upon carbon. 

414. Roeasler ft Hasslacher Chemical Company, The, Perth Amboy, 
N.J. 

Research staff: H. R. Carveth, technical director; M. J. Brown, 
B. S. Lacy, Sterling Temple, E. A. Rykenboer, chief chemists; 10 
research chemists with laboratory and engineering assistants. 

Research work : Half time on problems connected specifically with 
manufacture of caustic soda; inorganic and organic chlorine com- 
pounds; formaldehyde and its compounds; precious metals used in 
the arts, principally platinum, gold and silver; ceramic materials, 
alkali metals, alkali cyanides, peroxides and persalts ; metal cyanides ; 
also problems connected with utilization of products cited a)30ve in 
plating ; in bleaching and finishing of textiles ; in enamelling, rubber 
accelerators, fumigation. 

415. Royster, F. S., Guano Company, Norfolk, Va. 
Research staff : E. W. Magruder and 3 chemists. 

Research work : Small part time of 4 on fertilizer problems entirely, 
such as cause of hardening of acid phosphate, effects of different ma- 
terials on each other when mixed, etc. 

416. Rubber Trade Laboratory, The, 96 Academy St., Newark, N. J. 
(An advisory organization conducting researches by request in indus- 
trial establishments. Laboratory investigations are carried on at this 
address.) 

Research staff : Frederic Dannerth and 4 collegiate chemists. 

Research work : Investigations for the industries using rubber and 
related gums, paints, oils and varnishes. Investigations for the indus- 
tries which make rubberized and water proof fabrics ; coal tar prod- 
ucts. 
4x7. Rumford Chemical Works, Providence, R. I. (Baking powder. 



70 INDUSTRIAL RESEARCH LABORATORIES 

yeast powder, bread preparation, phosphatic baking acid, acid phos- 
phate, phosphoric acid solutions and similar products.) 

Research staff: Augustus H. Fiske, 2 assistant chemists and 5 as- 
sistants. 

Research work : Equivalent to two-thirds time of i on improvement 
of apparatus for manufacture of phosphoric acid and its salts; im- 
provement of processes of manutacture and of methods of testing 
products in laboratory. 

Equipment : Gas-measuring devices for testing baking powder and 
specially devised electrolytical apparatus for determination of ma- 
terial by electrolysis. 
417a. Sabine, Wallace Clement, Laboratcny, Riverbank, Geneva, 111. 

Research staff: Paul E. Sabine, 3 physicists and i mechanician. 

Research work : Full time of staff on transmission and absorption 
of sound by standard constructions, structural materials; physical 
characteristics of the ear ; absolute measurements in acoustics, special 
problems in architectural design and acoustics. 

Equipment: Sound chamber, calibrated sound sources, apparatus 
for sound photography, telephonic and other devices for absolute 
sound measurements. 
4x8. Saginaw Salt Products Co., Saginaw, Mich. 

Research staff : John P. Simons and 2 assistants. 

Research work: Approximately one-fourth time of 3 on chemical 
and engineering problems in connection with evaporators, removal of 
impurities from salt brine, etc. 
4x9. Sangamo Electric Con^mny, Springfield, 111. 

Research staff: F. C. Holtz, i chemist, 3 electrical engineers, 2 
assistants and 2 model makers. 

Research work : One-third time of 7 on properties of magnet steels ; 
endurance of material and precious stones used as bearings, paints, 
varnishes, insulations, brass and steel, development of apparatus em- 
ploying new principles of operation. 

420. Schaeffer Brothers ft Powell Manufacturing Company, 189 N. 
Clark St., Chicago, 111. Laboratory at 102 Barton St., St. Louis, Mo. 
(Soap, oils, etc.) 

Research staff: B. Nichols and 3 assistants. 

Research work: One-third time of 4 on vegetable, animal and 
mineral oil. 

421. Schwarr Laboratories, 113 Hudson St., New York, N. Y. (Food 
analyses and research; applied refrigeration; testing of fuels and 
lubricants.) 

Research staff: Robert Schwarz, 5 chemists, i biologist, i con- 
sulting mechanical engineer and 2 assistants. 

Research work: One-fifth time of 10 on food and beverage prob- 
lems, both chemical and biological. 

Equipment: Model brewery of 120 gallons capacity. 

422. Scientific Instrument and Electrical Machine Company, The, 500 
S. York and 221 West Coover Sts., Mechanicsburg, Pa. 

Research staff : W. W. Strong and i or 2 skilled men. 

Research work: Practically full time of 3 on ionization of gases. 



INDUSTRIAL RESEARCH LABORATORIES 71 

precipitation of fumes, deblooming oil, nitrogen fixation, diamond 
surfaced glass, smoke and fume recorders and masks, etc. 

Equipment: High voltage apparatus, gratings, ultra-violet appa- 
ratus. 

433. Scotty Ernest, & Companyy Fall River, Mass. (Engineers; ap- 
paratus for saving industrial wastes; vacuum evaporators, vacuum 
dryers, solvent extraction apparatus, ammonia stills, wood distillation 
plants.) 

Research staff: H. Austin and Robert W. Macgregor, 4 chemical 
engineers. 

Research work: One-tenth time of 6 on vacuum evaporation, 
vacuum distilling and solvent extraction. 

434. Scovill Manufacturing Company, Waterbury, Conn. (All 
varieties of brass, bronze and German silver.) 

Research staff: 3 metallurgists, i chief chemist and metallurgist 
with staff of 27 assistants; 2 mechanical engineers, i electrical en- 
gineer with 3 assistants, i plating and finishing expert with 2 as- 
sistants. 

Research work : About one-tenth time of technical staff is occupied 
with research problems. 

Equipment: Olsen 100,000-pound universal automatic and auto- 
graphic testing machine, 3-screw t3rpe, motor drive, speed 0.025 inch 
to 6.50 inches a minute ; Olsen 50,000-pound universal automatic and 
autographic testing machine similar to the 100,000-pound machine; 
Olsen 200,000-pound universal automatic testing machine; Riehle 
2,000-pound testing machine, hand drive for tensile tests only; 
Brinell hardness testing machine, capacity 3,000 kilograms pressure ; 
Olsen and Erichsen sheet metal testers, for ascertaining ductility; 
Shore scleroscope. 

425. Sears, Roebuck and Co., Chicago, 111. (Diversified manufac- 
turing and mail order business.) 

Research staff: G. M. Hobbs, director testing department, C. H. 
Higgfins, head chemical laboratory, Elizabeth Weirick, head textile 
laboratory, and L. E. Wolgemuth, head mechanical research labora- 
tory; 13 chemists, physicists and engineers. 

Research work: Approximately one-fourth time of staff on de- 
velopment of mechanical devices, methods, factory problems and the 
standardization of merchandise. 

Semet-Solvay Company. See Solvay Process Company, The 

(P- 72). 

426. Seydel Manufacturing Company, Jersey City, N. J. (Chem- 
icals.) 

Research staff : Paul Seydel and 4 to 6 assistants. 
Research work : Pharmaceutical and textile chemicals. 

427. Sharp & Dohme, Baltimore, Md. (Manufacturing chemists.) 
Research staff: Herman Engelhardt, 5 research chemists, i phar- 
macologist, I pharmacognosist and 10 pharmaceutical chemists. 

Research work: One-half time of 5 on pharmaceutical chemistry, 
crude drugs and synthesis of new compounds. 

Skayef Ball Bearing Co. See S. K. F. Industries, Inc. 



72 INDUSTRIAL RESEARCH LABORATORIES 

438. S. K. F. Industries, Inc.» New York, N. Y. Research Labora- 
tory, Front St. and Erie Ave., Philadelphia, Pa., also serves Hess- 
Bright Manufacturing Co., Philadelphia, Pa., Atlas Ball Company, 
Philadelphia, Pa., and Skayef Ball Bearing Co., Hartford, Conn. 

Research staff: Haakon Styri, 4 mechanical engineers, i chemist, 
2 metallurgists. 

Research work : Full time of staff on ball bearing application and 
endurance fatigue and improvement of material. 

429. Skinner, Sherman & Bsselen, Incorporated, 248 Boylston St., 
Boston 17, Mass. (Chemists and engineers.) 

Researeh staff: Gustavus J. Esselen, Jr., 9 chemists, 3 engineers 
and 3 bacteriologists. 

Research work: Approximately one-half time of 7 on paper, cellu- 
lose and its esters, food and canning industries, industrial bacteri- 
ology, adhesives and cement and building materials. 

430. Solvay Process Company, The, and Semet-Solvay Company, 
Syracuse, N. Y. (Alkali, coke and its by-products.) Do research 
work also for By-Products Coke Corporation, South Chicago, 111. 

Research staff : The Solvay Process Co., Carl Sundstrom, 10 chem- 
ists, 5 chemical assistants, 5 clerks and mechanics. Semet-Solvay Co., 
A. C. Houghton, i2 chemists, i chemical engineer, 2 electro-chemical 
engineers and 12 chemical assistants and routine men. 

Research work : Four-fifths time of 20 and one-half time of 37 on 
soda ash, caustic soda, bicarbonate of soda, lime and limestone, 
cement, waste disposal, metal corrosion, new alkali products ; potash, 
indigo, fixation of nitrogen, coal, light oils, causticizing, oxalic acid, 
sulphonation of benzol, picric acid, salicylic acid, chlorination of 
toluol, benzaldehyde, benzoic acid, and new products, such as di- 
phenyl oxide, benzyl acetate, benzyl benzoate, aspirin, sodium sali- 
cylate and cinnamic acid. 

Equipment: Electric, steam and gas ovens and furnaces of nearly 
all sizes up to 2x3x3 feet, capable of any temperature range up to 
1500 degrees C; temperature measuring equipment ranging from 
— 100 degrees C. to +1750 degrees C; laboratory kneading and mix- 
ing machine. 

43Z. Souther, Henry, Engineering Co., The, 11 Laurel St., Hartford, 
Conn. (Consulting engineers.) 

Research staff: J. A, Newlands, F. P. Gilligan, 7 technically trained 
assistants and 4 others. 

Research work : Part time of 6 on oils, waters and greases, ferrous 
and non-ferrous metals, methods of heat-treatment, electro-plating, 
foundry practice, boiler water treatment. 

Equipment: Pyrometers, furnaces, lead pot for experimental heat 
treatment; 100,000-pound Olsen physical testinp^ machine, Izod im- 
pact tester and White-Souther endurance machmes; Emerson bomb 
calorimeter. 

432. Southern Cotton Oil Company, The, 120 Broadway, New York, 
N. Y. Head laboratory at Savannah, Ga. 

Research staff : Herbert S. Bailey and 6 or 7 assistants. 

Research work : Problems pertaining to' the vegetable oil industry 
such as improved methods of analyses, investigation of catalysers and 



INDUSTRIAL RESEARCH LABORATORIES 73 

their preparation, improvements in the methods of refining vegetable 
oils, investigating and finding new uses for by-products. 

433. Speciid Chemicals Company, Highland Park, 111. 

Research staff: Carl Pfanstiehl, Robert S. Black and 3 assistants. 

Research work: Rare carbohydrates, amino acids, rare organic 
biological chemicals and industrial specialties. 

Equipment : New Bates variable sensibility half-shade polariscope ; 
use of bacteria as "living chemical reagents.'* 

434. Speer Carbon Company, St. Marys, Pa. (Motor and generator 
brushes.) 

Research staff : M. S. May, 2 engineers, 2 chemists and 3 assistants. 

Research work : Practically the entire chemical and electrical staff 
devoted to the development of new products and the improvement of 
present products. 

435-436. Spencer Lens Company, Buffalo, N. Y. (Optical instru- 
ments, optical glass.) Laboratory also at Hamburg, N. Y., in optical 
glass factory. 

435. Buffalo Laboratory 

Research staff: Harry G. Ott and 7 trained assistants. 

Research work : Half time of 8 on mathematical designing of lens 
systems ; the other half on designing optical instruments and solving 
the problems of the manufacture of lenses and optical instruments. 

430. Hamburg Laboratory 

Research staff: Donald E. Sharp and i trained assistant. 

Research work : Full time of 2 on optical glass and problems con- 
nected with its manufacture. 

437. Sperry, D. R., ft Co., Batavia, 111. (Founders and engineers; 
makers of filter presses and evaporators.) Sperry Filtration Labora- 
tory. 

Research staff: D. R. Sperry. 

Research work: One-fourth time of i on systematic effort to de- 
termine fundamental laws of filtration. 
Equipment : Special filter presses. 

438. Sprague, Warner ft Company, 600 West Erie St., Chicago, 111. 
(Manufacturers and wholesalers of groceries.) 

Research staff : Paul D. Potter and 2 trained chemists. 

Research work : One-third time of 3 on problems relating to food. 

439. Spreckels Sugar Company, 2 Pine St., San Francisco, Calif. 
Research staff : K. E. Christie, i chief chemist, 3 assistant chemists 

and 6 bench chemists through operating season of three months; i 
chief chemist and i assistant chemist in off season of nine months. 
Research work: Equivalent of time of i man for nine months on 
extraction and purification of juices; minimization of sugar losses; 
reduction of fuel-oil, lime and filter-cloth consumption; recovery of 
potash soda and ammonia compounds from Steffen waste. 

440. Squibb, E. R., ft Sons, New Brunswick, N. J. (Research and 
biological laboratories.) 

Research staff: John F. Anderson, 6 bacteriologfists and 3 chemists. 
Research work : One-fourth time of 10 on biological and biochemi- 
cal problems. 

Equipment : For the production, for commercial purposes, of prod- 



74 INDUSTRIAL RESEARCH LABORATORIES 

ucts for theoretical research in the various phases of biological thera- 
peutics. 

441. Stamford Dyewood Company, Stamford, Conn. 

Research staff: Roy H. Wisdom, i chemist and i engineer. 

Research work : One-tenth time of 3 on improvement in manufac- 
ture of dyewood extracts and economical methods of use of waste 
products. 

442. Standard Oil Company (New Jersey), 26 Broadway, New York, 
N. Y. Central laboratory at Linden, N. J. Other laboratories at prin- 
cipal plants of the Standard Oil Company in the United States and 
abroad. 

Research staff: Frank A. Howard, manager, C. I. Robinson, chief 
chemist, C. O. Johns, director research laboratory, N. E. Loomis, di- 
rector, experimental division. 

Research work: Petroleum production, products and refining, nat- 
ural and artificial gas. 

443. Standard Oil Company of Indiana, Whiting, Ind. 

Research staff : F. M. Rogers, 7 chemists and 6 assistants. 

Research work : Full time of 7 on improvement of niethods of pe- 
troleum refining; development of new products and new processes; 
study of nature and properties of petroleum products. 

Ecjuipment: Fully equipped experimental plant for carrying out 
refinmg methods on a scale larger than is possible in the laboratory. 

444. Standard Underground Cable Company, 26 Washington St., 
Perth Amboy, N. J. 

Research staff: G. D'Eustachio and 2 assistants. 
Research work: Approximately half time on insulating material 
for electrical purposes. 

Staniford Laboratories. See Porro Biological Laboratories. 

(p. 65). 

445. Stewart - Warner Speedometer Corporation, Chicago, 111. 

(Speedometers, tachometers, vacuum gasoline systems, and other 
automobile accessories.) 

Research staff : F. G. Whittington, chief engineer, i assistant chief 
engineer, i research engineer, 3 assistant research engineers, i elec- 
trical engineer, 2 designers and inventors. 

Research work: Full time of 5 on investigations of fuel feed sys- 
tems, speedometers, tachometers, and other automobile equipment. 

Equipment: For testing tachometer and speedometer indications 
at varying temperatures, from —20 to 250* F. Sprague electric, 
cradle type dynamometer, capacity 50 to 75 h. p. 4000 maximum 
revolutions per minute ; torsion machines ; special flux meter for mag- 
netic investigation work. 

446. Stockham Pipe ft Fittings Co., Birmingham, Ala. (Cast iron 
fittings.) 

Research staff: R. E. Risley. 

Research work: Full time of i on heat treatment of high speed 
steel, molding sand selection and treatment and briquetting and re- 
melting^ cast iron borings. 

Equipment: Special equipment for physical testing of molding 
sand. 



INDUSTRIAL RESEARCH LABORATORIES 75 

447. Stone & Webster^ Incorporated^ 147 Milk St., Boston, Mass. 
(Engfineers, constructors, bankers, operators of public utilities.) 

Research staff: 2 chemists, 2 mechanicians. 

Research work: Full time of 4 on needs of industrial companies. 

448. Strathmore Paper Company, Mittineague, Mass. 
Research staff: Justus C. Sanborn and i assistant chemist. 
Research work : One-fifth time of 2 on special paper mill problems. 

449* Structural Materials Research Laboratory, Lewis Institute, 195 1 
W. Madison St., Chicago, 111. 

Research staff : Duff A. Abrams in charge of laboratory ; J. C. Witt, 
chief research chemist, and 30 engineers, physicists and chemists. 

Research work : Full time of 32 on the properties of concrete and 
concrete materials, reinforced concrete and related topics. Research 
is being carried on through a cooperative arrangement between the 
Lewis Institute and the Portland Cement Association. 

Equipment: One 300,000-pound, two 200,000-pound and one 
40,000-pound screw-power universal testing machines, 20,000-pound 
torsion testing machine, 4-unit Deval abrasion machine and standard 
ball mill for tests of road materials, Ro-Tap sieve shaker for fineness 
tests of materials, Talbot-Jones rattler for wear tests of concrete, 
autoclave apparatus for high-pressure steam tests of cement. 

450. Studebaker Corporation, The, Detroit, Mich. (Automobiles and 
other vehicles.) 

Research staff: E. J. Miles, 2 engineers and i mechanic in the 
dynamometer department ; i electrical engineer and i assistant in the 
electrical department; i chemist in the chemical department, i engi- 
neer, I assistant and a staff of mechanics in the road testing depart- 
ment, I engineer on special work. 

Research work : One-half to two-thirds time of staff on power out- 
put of motors, investigations of electrical appurtenances for automo- 
biles, chemical studies of materials used in manufacture, road testing 
of automobiles, special problems related to radiators, brakes, oil 
pumps, fans and other equipment of an automobile. 

Equipment : Research laboratory : 3 complete electric dynamome- 
ter equipments for motors up to 80-horsepower output; completely 
equipped for investigations of ignition apparatus, lighting and start- 
ing apparatus, storage batteries and all other electrical appurtenances 
of automobiles ; special equipment for investigating oils and grease. 

451. Sun Chemical ft Color Co., 309 Sussex St., Harrison, N. J. (Dry 
and pulp colors.) 

Research staff: 2 chemists and i assistant. 

Research work : One-half time of 3 on improving lake and pigment 
colors. 
45a. Swan-Myers Company, 219 N. Senate Ave., Indianapolis, Ind. 

Research staff: Edgar B. Carter, director of biological division, A. 
D. Thorburn, director of pharmaceutical division, 2 chemists and 5 
bacteriologists and biological chemists. 

Research work : Approximately one-fourth time of 9 on biological 
products and organic synthetics used in medicine and pharmaceutical 
products. 



76 INDUSTRIAL RESEARCH LABORATORIES 

453. Swenson Evaporator Company, 945 Monadnock Building, Chi- 
cago, 111. Laboratory at Ann Arbor, Mich. 

Research staff : W. L. Badger, i chemical engineer, assistants and 
I helper. 

Research work: Full time on design of evaporators and other 
chemical engineering machinery ; trial of processes and theoretical re- 
search on heat transmission in general. 

Equipment: Large specially designed evaporators of all types. 
Accessory equipment so that processes can be carried out on ton or 
carload lots of material. 

454. Swift ft Company, Chicago. 111. 

Research staff: William D. Richardson and 9 assistants. 

Research work: Full time of 10 on foods and dietetics, meat and 
meat products, dairy products, oils and fats, soap and soap products, 
glue and gelatin, fertilizers. 

Equipment: Vacuum drying apparatus, agitator pressure tanks, 
special chill rooms. 
455* Tacony Steel Company, Philadelphia, Pa. 

Research staff: H. A. Baxter and approximately 25 assistants. 

Research work: On manufacture and use of special carbon and 
alloy steels for high duty structural service. 

456. Taggart and Yerza, 165 Division St., New Haven, Conn. 
Research staff: Arthur F. Taggart, R. B. Yerxa, 3 chemists and 3 

engineers. 

Research work: Full time of 8 on flotation concentration of ores. 

457. Takamine Laboratory, Inc., Takamine Bldg., 12 Dutch St., New 
York, N. Y. (Manufactunng chemists.) Laboratory at Clifton, N. J. 

Research staff: Jokichi Takamine, 4 chemists and i assistant. 
Research work: Full time of 6 on biological, physiological and 
organic chemistry. 

458. Teeple, John E., 50 E. 41st St., New York, N. Y. (Consulting 
chemist, chemical engineer.) 

Research staff: John E. Teeple and 2 to 4 chemists. 
Research work : Full time of 2 to 4 on investigations necessary for 
directing research work in the laboratories of clients. 

459. Telling-Belle Vernon Company, The, 3825 Cedar Ave., Cleve- 
land, Ohio. 

Research staff: W. O. Frohring, 2 bacteriologists and 2 chemists. 
Research work : Three-fourths time of 5 on milk and milk products, 
with large portion of time on ice cream and infant foods. 

460. Tluic Industrial Products Corp., 58 Middle Rose St., Trenton, 
N.J. 

Research staff : A. I. Appelbaum and 2 assistants. 

Research work : Part time of 3 on development of by-products. 

461. Titanium Alloy Manufacturing Co., Niagara Falls, N: Y. 
Research staff: L. E. Barton, chief chemist, 2 assistant chemists 

and I helper. Physical testing laboratories, G. F. Comstock, metal- 
lurgist and 2 metallographists. 

Research work: On problems related to the manufacture and use 
of ferro-carbon titanium and zirconium and zirconium products for 
ceramic industries. 



INDUSTRIAL RESEARCH LABORATORIES 77 

46a. Titanium Pigment Co., Inc.» Niagara Falls, N. Y. 

Research staff : L. E. Barton, chief chemist, research and technical 
control of plant, and 4 assistant chemists. 

Research work: On manufacture and use of titanium pigments, 
titanium salts and other titanium products. 

463. T. M. ft O. Chemical Co., 517 Cortlandt St., Belleville, N. J. 
(Manufacturing chemists.) 

Research staff: O. Ivan Lee and 3 assistants. 

Research work : Approximately one-half time of 4 on development 
of commercial processes for the manufacture of organic chemicals 
with special reference to intermediates, dyes, and aromatic synthetics 
for soaps and perfumes ; systematic study of the synthesis, separation 
and purification of secondary and tertiary aromatic amines ; chlorina*- 
tion products of aromatic hydrocarbons; and utilization of by- 
products. 

464. Toch Brothers, 320 Fifth Ave., New York, N. Y. (Paints, var- 
nishes, colors, enamels ; acid, alkali and damp-proof coatings.) 

Research staff : Maximilian Toch and 4 to chemists. 

Research work : • Problems related to water-proofing and protection 
of Portland cement by inte^^l and surface coating methods ; water- 
proofing of structural materials ; anti<<orro8ive paints and compounds. 

465. Tolhurst Machine Works, Troy, N. Y. (Specialists in centrifu- 
gals: hydro-extractors.) 

Research staff: T. A. Bryson, usually i engineer and i or 2 as- 
sistants. 

Research work: One-sixth time of 3 on determination of profitable 
methods of separation (and washing) of liquids from liquids or solids 
by means of centrifugal force; apparatus for dewatering sewage 
sludge ; separation of foots from oil, recovery of glycerine and salt in 
soap industry, and improved methods of treating fish and fish oil. 

Equipment: Centrifugal machines for filtration, extraction and 
sedimentation, ranging from small hand-driven, tube and basket cen- 
trifuges to higher speed 12 gallons basket capacity centrifugals, with 
interchangeable baskets of various types for crystalline, granular or 
fibrous materials, slimes and sludges. 

466. Tower Manufacturing Co., Inc., 85 Doremus Ave., Newark, N. J 
Research staff: C. P. Harris, 7 chemists and 2 engineers. . 
Research work : Three-tenths time of 10 on processes for the manu- 
facture of dyes and intermediates. 

Equipment: Completely equipped semi-commercial plant. 

467. Ultro Chemical Corporation, 41 Union Square, New York, N. Y. 
(Colors and chemicals.) Laboratory at 236 40th St., Brooklyn, N. Y. 

Research staff : A. £. Gessler, i chemist and i assistant. 
Research work: Approximately full time of 3 on dry colors and 
dyestuffs. 

468. Underwriters' Laboratories, 207 E. Ohio St., Chicago, 111. Es- 
tablished and maintained by National Board of Fire Underwriters. 
Departments: Protection, electrical, gases and oils, chemical, cas- 
ualty. Laboratory also at 25 City Hall Place, New York, N. Y. 

Research staff : W. H. Merrill and 50 experts and necessary as- 
sistants. 



78 INDUSTRIAL RESEARCH LABORATORIES 

Research work : A variable but large proportion of time of staff on 
matters affecting performance and classincation devices, materials and 
systems affecting the fire hazard or the personal accident hazard. 
468a. Uniform Adhesive Company, Incorporated, foot of 39th St., 
Brooklyn, N. Y. 

Research staff : Jerome and Walter Alexander. 

Research work: Part time on adhesives, colloids, gums, starches, 
colors, sizings, finishings, etc., for paper and textiles. 

469. Union Carbide and Carbon Research Laboratories, Inc., Thomp- 
son Ave. and Manley St., Long Island City, N. Y., a subsidiary of the 
Union Carbide & Carbon Corporation, New York. Central Research 
laboratory at Long Island City and branch research and development 
laboratories at Long Island City and Buffalo, and two at Niagara 
Falls, N. Y.; two at Cleveland and one at Fremont, Ohio; one each 
at Indianapolis and Kokomo, Ind., and Clendenin, W. Va. 

Research staff: Central laboratory has a staff of over 40, and 
branches combined, over 30, including chemists, chemical, metallur- 
gical and electrical engineers and physicists. 

Research work : Full time of staff on metallurgical and other elec- 
tric furnace products, calcium carbide, compressed gases, carbon 
products, dry batteries and storage batteries, flashlights, organic 
chemicals and equipment for using the above products. 

Equipment: Electric furnaces of various types; alloy testing and 
pyrometric equipment; gas compressing and testing equipment; ap- 
paratus for making and testing dry batteries, storage batteries, arc 
light carbons and brushes for electric motors and generators. 

470. Union Switch ft Signal Company, Swissvale, Pa. (Railway sig- 
nal equipment.) Materials laboratories are maintained separately 
under the direction of H. C. Loudenbeck, with 3 chemists. 

Research staff: L. O. Grondahl, 2 engineers and i assistant in 
charge of standardizing laboratory. 

Research work: Two-thirds time of 4 on development of iron for 
electro-magnets, heat treatments, methods of test, electrical contacts, 
insulators, impregnation of coils and of wood. 

Equipment: Oscillographs; standardizing equipment for electrical 
instruments; 50,000-volt insulation testing transformer; Heissler im- 
pact testing machine ; an experimental impregnating plant, oil heated, 
with vacuum and pressure pump ; and salt spray tester. 

471. United Alloy Steel Corporation, Canton, Ohio. (Open hearth 
and electric steels, bars, slabs, billets, blooms, universal plates.) 

Research staff : M. H. Schmid, i metallurgical engineer, i assistant 
metallurgical engineer, i laboratory foreman, 10 assistants and i en- 
gineer of tests ; m the Electric Furnace, i chief and 2 recorders ; in 
the Open Hearth Furnace, i chief and 8 recorders; in the Rolling 
Mills, I chief and 4 recorders. 

Research work: One-half time of 32 on investigations connected 
with production and use of steel. 

Equipment : Heat treatment : 4 Hoskins' electric furnaces, i Amer- 
ican gas furnace for pieces up to 20 inches length and 5 inches diame- 
ter. Physical testing: equipped for tensile, torsion, cold bend, vibra- 
tory, Izod, Brinell, scleroscope, staybolt, etc. ; also Leeds & Northrup 



INDUSTRIAL RESEARCH LABORATORIES 79 

permeameter for determining magnetic permeability of steel and i 
Leeds & Northrup recalescence instrument for determining critical 
points of steel. 

472. United Chemical and Organic Products Co., W. Hammond, 111. 
(Successors to Hirsh, Stein & Company.) 

Research staff: Jay Bowman and 4 chemists. 
Research work : One-half time of 5 on problems arising in connec- 
tion with plant processes. 

Equipment: Semi-manufacturing scale equipment. 

473. United Drug Company, Boston, Mass. 
Research staff : Edward C. Merrill and 10 chemists. 

Research work: One-half time of 10, largely on pharmaceutical 
investigations and research, and independent problems covering mis- 
cellaneous subjects. 

474. United Gkis Improvement Co., The, 3101 Passyunk Ave., Phila- 
delphia, Pa. 

Research staff: Edward J. Brady and 3 assistants. 

Research work: Problems dealing only with the manufacture, 
purification, measurement and combustion of gas and the development 
of instruments in connection with the above. 

Equipment : Laboratory water gas plant ; laboratory blue gas gen- 
erator; the use of a separate and complete commercial-sized experi- 
mental plant available at times ; furnaces for refractory testing ; high 
pressure gas equipment; complete physical equipment for high tem- 
peratures; high gas pressures; evacuating spectroscopy; electrical 
standards ; radiation measurements ; photometry and color. 

475. United Shoe Machinery Corporation, Boston, Mass. Laboratory 
at Beverly. 

Research staff: Walter Gould Bullard and assistants. 
Research work: Examination of raw materials; tests on core oils 
and compounds, systematic investigation on improvement in antiseptic 

Suality of cutting compounds and on pickling steel bars and plates, 
ome work on reclamation of waste materials and in attempts to im- 
prove methods of manufacturing shoe-factory supplies of all kinds. 

476. United States Bronze Powder Works, Inc., Closter, N. J. 
Research staff: Everett S. Landman and 2 chemical engineers. 
Research work : One-fifth time of 3 on oxidation and reduction of 

finely divided copper, properties and composition of bronzing liquids, 
non-tamishable bronze powders and anti-fouling boat bottom com- 
positions; pulverized copper and alloys for manufacture of electrical 
brushes. 

U. S. Conditioning and Testing Co. See U. S. Testing Co., Inc. 
(p. 80). 

477. U. S. Food Products Corp., Peoria, 111. 
Research staff: J. K. Dale and 2 chemists. 

Research work : Full time of 3 on food development problems. 

478. United States Glue Co., Milwaukee, Wis. 
Research staff : C. R. McKee and 3 trained men. 

Research work : One-half time of 4 on improvements in technology 
in glue and gelatine industry, particularly development of processes 
to produce glue and gelatine for various specific purposes, such as 



go INDUSTRIAL RESEARCH LABORATORIES 

gelatine with various photographic properties, food gelatine, marsh- 
mallow gelatine and special glue. 
Equipment: Complete miniature glue and gelatine factory. 

479. U. S. Industrial Alcohol Company, 27 William St., New York, 
N. Y. Laboratory at South Baltimore, Md. 

Research staff : A. A. Backhaus, 12 chemists, 2 bacteriologists, 10 
assistant chemists and 2 chemical engineers. 

Research work: Full time of staff on research in connection with 
the development of alcohol products, utilization of by-products of 
alcohol manufacture, improvement in the manufacture of alcohol, 
study of yeasts and bacteria. 

480. United States Metals Refining Co., Chrome, N. J. 

Research staff: H. D. Greenwood, in charge of chemical depart- 
ment, W. C. Smith in charge of metallurgical department; about 42 
assistants. 

Research work : Part time of staff on maintaining a high standard 
in plant metallurgy and discovering new and improved methods. 

481. United States Smelting, Rdi^g ft Mining Company, 55 Con- 
gress St., Boston, Mass. (Silver, gold, lead, copper, zinc, iron, arsenic, 
bismuth, cadmium, and tellurium.) Plants and research laboratories 
located at various points in the United States and Mexico. 

Research staff : Galen H. Clevenger and 20 engineers, chemists and 
other specialists. 

Research work : Full time on metallurgy, industrial chemistry and 
mining in the development of new processes, improvements in ex- 
istent processes, investigation of new processes submitted and ex- 
amination and improvement of products. 

Equipment: Thirty-liter-per-hour liquid oxygen machine, equip- 
ment for investigating liquid oxygen explosives and for determining 
the volatilization losses of the precious metals during melting, reduc- 
ing kiln of 50 tons daily capacity, experimental bag house, and ex- 
perimental farm for the study of the effect of smelter fume upon grow- 
mg crops and animal life. 

United States Steel Corporation. See Carnegie Steel Company 
(p. 18). 

482. U. S. Testing Co., Inc., 316 Hudson St., New York, N. Y. 
Research staff: W. F. Edwards, 5 chemists, 3 engineers and i 

physico-chemist. 

Research work : One-half time of 10 on investigations of problems 
arising in textile and allied industries. 

Equipment : Apparatus for investigation of effect of light on dyed 
textiles. 

483. Universal Aniline Dyes and Chemical Co.» nth and Davis Sts., 
S. Milwaukee, Wis. 

Research staff : A. H. Schmidt and 2 assistants. 
Research work : Approximately one-half time of 3 on intermediates 
and dyes. 
Equipment: Complete miniature plant equipment. 

484. Upjohn Company, The, Kalamazoo, Mich. (Fine pharmaceutic 
cals.) 



INDUSTRIAL RESEARCH LABORATORIES 81 

Research staff : Frederick W. Heyl, 4 or 5 chemists, i pharmacolo- 
gist, I bacteriologist. 

Research work: Part time of 7 on estimation of nitroglycerine; 
analyses of two Echinacea roots; standardization of commercial pa- 
pain; some constituents of the roots of Brauneria augustifolia ; some 
constituents of Sunbul root; standardization of the mercurials; Al- 
genta root ; some constituents of jambul ; analysis of ragweed pollen ; 
chemical examination of the leaves of Adonis vernalis; protein ex- 
tract of ragweed pollen ; yellow coloring substance of ragweed pollen ; 
some constituents of Viburnum prunifolium, stability of Digitalis leaf 
extracts and infusions ; pharmacological action of Adonis vernalis, 
485. Utah Copper Company, Deseret Bank Bldg., Salt Lake City, 
Utah. Laboratory at Garfield. Utah. 

Research staff: Thomas AJ Janney, 6 chemists, 4 engineers and 
3 assistants. 

Research work : Three-fifths time of 16 on treatment of ores by the 
flotation process, gravity concentration, lixiviation and related inves- 
tigations, flotation oils and reagents. 
4M. UtEih-Idaho Sugar Company, Salt Lake City, Utah. 

Research staff: E. G. Titus, i research assistant, i agricultural 
chemist, and i laboratory assistant. 

Research work: Approximately one-half time of 4 on agricultural 
problems, beet-seed breeding, crop improvement, seed testing, soil 
reclamation and analysis, fertilizer experiments, and insect^ disease 
and weed control. 

Equipment: Special beet testing machinery, seed germination ap- 
paratus. 

487. Utility Color ft Chemical Co., The, 395 Frelinghuysen Ave., 
Newark, N. J. 

Research staff : Joel Taub and 2 assistants. 

Research work: One-half time of 3 on development of colors. 

488. Vacuum Oil Company, Incorporated, 61 Broadway, New York, 
N. Y. (Refiners of petroleum for all purposes ; manufacturers of ship- 
ping containers and of products used in the leather industry, etc.) 
Works and laboratories at Rochester and Olean, N. Y., Paulsboro and 
Bayonne, N. J. 

Research staff : Florus R. Baxter, 3 chemists at Rochester ; i chem- 
ist each at Olean, Paulsboro and Bayonne, also 12 assistants. 

Research work: One-fifth time of 7 studying improvements in 
manufacturing methods; causes of deterioration of oils in service; 
utilization of by-products, properties of petroleum to determine suit- 
ability for specific uses. 

Equipment: Fire, steam and vacuum stills, lead lined agfitators, 
fully equipped, wax presses, super-centrifuges, photomicrographic set, 
apparatus for measurements of specific resistance, di-electric loss and 
di-electric strength, etc.. 

489. Vanadium- Alloys Steel Co., The,^ Latrobe, Pa. (High speed, 
alloy and carbon steels.) 

Research staff: James P. Gill and 9 assistants. 
Research, work : Approximately one-third time of 10 on alloy tool 
steels, high speed and special steels. 



82 INDUSTRIAL RESEARCH LABORATORIES 

490. Vanadium Corporation of America, 120 Broadway, New York, 
N. Y. Laboratory at Bridgcville, Pa. 

Research staff: B. D. Saklatwalla, 5 chemists, i chemical engineer 
and I electrochemical engineer. 

Research work: One-half time of 8 on metallography of alloy 
steels, development of metallurgical processes for alloying elements 
and development of electro-thermic methods of reducing metals. 
49Z. Van Schaack Brotiiers Chemical Works, Inc., 3358 Avondale 
Ave., Chicago, 111. (Amyl acetate, soluble cotton, etc.) 

Research staff : R. H. Van Schaack, Jr., and 4 assistants. 

Research work: Approximately one-half time of 5 on nitrocellu- 
lose solvents. 

492. Ventura Refining Company, Fillmore, Calif. 
Research staff : J. W. Weir and 7 assistants. 

Research work : One-seventh time of 8 on petroleum refinery prob- 
lems. 

493. Vesta Battery Corporation, 2100 Indiana Ave., Chicago, 111. 
(Storage batteries, auto dynamos, etc.) 

Research staff: Chester M. Angell, i chemist, i battery engineer 
and I assistant. 

Research work: Approximately one-fourth time of 4 on electro- 
chemistry, practical engineering features and improvement of parts 
and materials used in manufacture of the lead plate storage battery. 

494. Victor Chemical Works, Fisher Building, Chicago, 111. Large 
laboratory for factory control and general work and two smaller ones 
for research. 

Research staff: L. D. Mathias, 5 chemists and i engineer. 
Research work : Full time of 6 and one-half time of 2 on problems 
connected with manufacturing activities. 

495. Wadsworth Watch Case Co., Incorporated, The, Dayton, Ky. 
Research work : Approximately full time of 5 on alloys of precious 

metals and some of the brasses. 

496. Wahl-Henius Institute, Incorporated, 1135 Fullerton Ave., Chi- 
cago, 111. 

Research staff : Max Henius, 3 experts, i chief analytical chemist, 
I chief research chemist, 2 assistant chemists and 3 assistants. 

Research work : Full time of chief research chemist and about one- 
half time of I assistant chemist on fermentation and packing-house 
problems. 

Equipment : Apparatus for testing products of fermentation indus- 
tries and for carrying out experimental work on semi-commercial 
scale (experimental brewery, bottlery, etc.). Apparatus for testing 
solid and liquid fuel, and lubricants; differential refractometer 
(Tomoc's). 

497. Wallace ft Tieman Co., Inc., Box 178, Newark, N. J. (Chlorine 
control apparatus.) 

Research staff: C. F. Wallace, G. C. Baker, 3 chemists and 2 
engineers. 

Research work: Lar^ part time of 7 on chlorine gas control and 
applications in sterilization, bleaching and other lines ; flour bleaching ; 
carburetor laws and mechanical applications; and food products. 



INDUSTRIAL RESEARCH LABORATORIES 83 

Equipment: Carburetor testing outfit complete and chlorine con- 
trol equipment. 

498. Wallace, Joseph H., ft Co., 5 Beekman St., New York, N. Y. 
(Industrial engineers.) Laboratory at Webbs Hill, Stamford, Conn., 
R. F. D. 29. 

Research staff: F. E. Greenwood, i consulting engineer and i 
chemist. 

Research work : Full time of 3 on cellulose and by-products, pulp, 
paper, naval stores, etc. 

Equipment : Semi-commercial plant for pulp, paper and by-products. 

499. Waltham Watch Company, Waltham, Mass. 
Research staff : F. P. Flagg and 3 chemists. 

Research work: Full time of 2 on investigation of the properties 
of enamel used on watch dials and study of the properties of metals 
and their relation to watch production. 

500. Warner, William R., ft Company, Incorporated, 113 W. i8th St., 
New York, N. Y. (Manufacturing pharmaceutists.) v 

Research staff: Frederick J. Austin, Charles Costa. 

Research work: Chemical and pharmaceutical research which has 
for its object the improvement of products as regards physiological 
activity, permanence, elegance, etc., together with original work lead- 
ing to the development of new preparations and new methods of manu- 
facture. 

Warren, S. D., Co. See Cumberland Mills (p. 24). 
50Z. Washburn-Crosby Co., Minneapolis, Minn. (Flour mills.) 

Research staff : Frank W. Emmons, 3 chemists, i specially trained 
physical laboratory man, i expert baker and various assistants. 

Research work : Full time of i on problems relating to wheat flour. 

502. Wayne Oil Tank and Pump Co., Ft. Wayne, Ind. (Tanks, 
pumps and underground storage outfits.) 

Research staff: R. E. Langston, i chemist and 2 engineers. 

Research work : Approximately three-fourths time of 3 on devising 
improved methods of handling, storing and using volatile and non- 
volatile liquids, such as gasoline, paint oil, varnish, lubricating oil, 
fuel oil, kerosene, etc. ; methods of reclaiming used auto oil and puri- 
fication of used engine oil. 

503. Wedge Mechanical Furnace Company, 1000 Widener Bldg., 
Philadelphia, Pa. (Roasting furnaces.) Laboratory at Greenwich 
Point, Philadelphia, Pa. 

Research staff: Carl S. Fogh and a variable number of assistants. 
Research work: Full time on roasting ores, concentrates, mattes, 
mixtures and various materials for smelters and chemical plants. 

504. Weld and Liddell, 2 Rector St., New York, N. Y. (Consulting 
engfineers.) Laboratory at 961 Frelinghuysen Ave., Newark, N. J. 

Research staff: Donald M. Liddell, 3 trained men and 2 untrained 
assistants. 

Research work : Variable amount of time of 6 on stucco, zinc oxide, 
oil shale and petroleum. Balance of time on research problems of 
The Gray Industrial Laboratories. 

Equipment: Completely equipped for pressure and steam distilla- 
tions on oil shales or any bituminous or oily products. 



S4 INDUSTRIAL RESEARCH LABORATORIES 

505. Wellt, Raymond, Homer, N. Y. (Chemist and technologist.) 
Research staff: Raymond Wells and 2 assistants. 

Research work : One-half time of 3 on animal and vegetable oils ; 
fertilizers, soap, candles and glycerine ; abattoir by-products ; garbage 
and sewage disposal ; lubrication oils and greases ; wire mill soaps and 
drawing compounds; textile soaps and oils and agricultural insecti- 
cides and fungicides. 

Equipment: Commercial scale equipment for research in oils, etc. 

506. Welsbach Company, Gloucester, N. J. (Mantles for illuminating 
gas.) 

Research staff: Harlan S. Miner and 6 trained men. 

Research work : One-half time of 7 directed especially to economic 
production of rare earth chemicals, especially thorium and cerium; 
manufacture of special rare earth salts, nitration of cellulose, produc- 
tion of mesothorium ; radio-chemistry. 

Equipment: Especially for the study of problems connected with 
development of incandescent gas mantles. 

507. Western Electric Company, Incorporated, 463 West St., New 
York, N. Y., known as the Research Laboratories of the American 
Telephone and Telegraph Company and the Western Electric Com- 
pany, conducts research and engineering activities for the Bell Tele- 
phone System. 

Research staff: F. B, Jewett, chief engineer, E. B. Craft, K H. 
Colpitts and W. F. Hendry, assistant chief engineers ; heads of func- 
tional activities : H. D. Arnold, J. J. Lyng, R. L. Jones, A. F. Dixon, 
J. W. Harris, L. Keller, H. C. Snook, J. B. Harlow, G. A. Aoderegg 
and H. E. Shreeve who have under their direction approximately 825 
research physicists, chemists and engineers, and approximately 750 
assistant engineers, draftsmen, etc. 

Research work: Full time of 1575 devoted to original investiga- 
tion and development of new forms and improvement of existing 
forms of apparatus and equipment for electrical communication. The 
problems include research m thermionic emission and conduction, 
vacuum tube performance, microphonic conduction, radio transmis- 
sion, the physical basis of speech, wave and impulse propagation and 
the physical and chemical properties of a great variety of materials ; 
the development and design of full-mechanical and semi-mechanical 
telephone switchboards and systems in preparation for a comprehen- 
sive service transformation from the present manually operated sys- 
tem; the development and design of high frequency carrier systems 
with their associated generators, oscillators, modulators, hybrid coils, 
repeaters, loading coils, demodulators, amplifiers, and other special 
apparatus; development of new forms of local and long distance 
cables, submarine cables, transmitters, receivers, automatic printing 
telegraph apparatus, lightning arresters, protective fuses, current rec- 
tifiers, ringers, ringing systems, precision apparatus for high fre- 
quency measurements, marine radio sets, portable radio sets, trans- 
mitter life test methods, test methods for transmission efficiency, dry 
cells, storage cells, farm-light sets, household appliances and numer- 
ous problems in the design of keys, cords, plugs, switches, relays, con- 
tacts, loading coils, impedance coils, repeaters, transformers, con- 



INDUSTRIAL RESEARCH LABORATORIES 85 

densers, insulators, lamps, and kindred details of communication ap- 
paratus and systems. 

A thirteen story building of 400,000 square feet floor area. Physical 
research laboratory, transmission research laboratory, chemical re- 
search laboratory and physical testing laboratory completely equipped 
with all facilities necessary for this work; also completely equipped 
shop for the construction of working models and special equipment 
used in conducting research and development work. 

508. Western Gas Construction Company, The, 1429 Buchanan St., 
Ft. Wayne, Ind. (Designers and builders of water, coal and gas ap- 
paratus, gas holders and special equipment.) 

Research staff: F. Salathe, 2 chemists and 3 engineers. 
Research work : One-fourth time' of 6 on oils, gas, general organic, 
mechanical and chemical engineering. 

509. Western Precipitation C<mipany, 1016 W. Ninth St., Los An- 
geles, Calif. (Chemical engineers.) 

Research staff : H. V. Welch, i physicist, i engineer, 3 chemists. 

Research work: Three-fourths to nine-tenths time of 6 on prob- 
lems centering around the Cottrell Processes of electrical precipitation. 

Equipment: i5o,ooo»Yolt transformer, 50,000-volt direct current 
generator, high potential mechanical rectifiers, potash laboratory, di- 
gestion and filtration apparatus and special apparatus adapted for 
study of equilibrium conditions in solutions. 

510. Western Research Corporation, Incorporated, 514 i8th St., Den- 
ver, Colo. 

Research staff : James M. McClave, i chemist and i oil chemist. 

Research work: One-half time of 3 on investigation of minerals 
and non minerals, oils and shales; special attention to working out 
treatment methods and the construction of plants. 
51 z. Western Sugar Refinery, Foot 23d St., San Francisco, Calif. 

Research staff: S. C. Meredith, i chief chemist, 3 engineers and 
3 assistant chemists. 

Research work : Two-fifths time of 8 on investigations of sugar 
losses, sugar machinery and materials. 

5x2-5x3. Westinghouse Electric ft Manufacturing Company, East 
Pittsburgh, Pa. (Electrical apparatus of all kinds.) Laboratory also 
at Essington, Pa. 

512. East Pittsburgh Laboratory 

Research staff, scientific: C. £. Skinner, manager of research de- 
partment, 10 chemists, 28 physicists, and an operating staff of 23, in- 
cluding plant engineer, office staff, glass blowers, instrument makers, 
etc. 

Research work: Chemical division, organic materials, inorganic 
chemical research and analytical chemistry; division of physics and 
metallurgy, magnetic testing and research, magnetic materials, metal- 
lurgical preparations, metallurgical testing and research, electrolytic 
condensers, power condenser research, insulating materials, electrical 
porcelain, radio bulbs, thermal conductivity and expansivity, resister 
materials, etc. 

Equipment: Electric furnaces and rolls for metallurgical prepara- 
tions, high vacuum apparatus, special magnetic testing apparatus. 



86 INDUSTRIAL RESEARCH LABORATORIES 

thermal conductivity and expansivity apparatus and conductivity of 
dielectrics. 

Research staff, technical : R. P. Jackson, manager of materials and 
processes department, 8 chemists, 2 physical test men, 10 specialists 
on materials and their uses and 35 technical and other assistants. 

Research work : 5 research laboratories in which work is conducted 
on technical problems connected with manufacture and testing of raw 
materials and finished products. 

Equipment: High tension testing, special oscillographs and test* 
ing machines for determining physical properties. 

Standard house: O. B. Riley with staff of about 11 engaged in 
checking and testing standard instruments and apparatus, chiefly 
electrical. 

513. Essington Laboratory 

Research staff : A. T. Kasley and 4 assistants. 

Research work: Problems connected with heat and power. 
5x4. Westinghouse Lamp Co.« Bloomfield, N. J. Engineering and de- 
velopment laboratories under the direction of R. E. Myers with a 
staff of 85. 

Research staff: H. C. Rentschler, 3 physicists, 3 assistant physi- 
cists, 2 chemists and i assistant chemist. 

Research work: Full time of 9 on study of radiation from solids 
and gases and vapors; also high vacua phenomena. 

Equipment : Apparatus for obtaining and measuring high vacua, 
for producing high potential rectified current and for photometric and 
optical pyrometer measurements. High frequency electric furnace. 
Liquid air available at all times. Rare gases for study of their prop- 
erties and uses are available. 

515. Weston, Byron, Co., Dalton, Mass. (Ledger and record paper.) 
Research staff : P. W. Codwise and i assistant. 

Research work : Varying amount time of 2 on problems connected 
with paper making. 

516. Weston ft Sampson, 14 Beacon St., Boston, Mass. (Consulting 
engineers; water sanitation.) 

Research staff: Robert S. Weston, i chemist and i engineer. 
Research work: Part time of 3 on water, sewage and sanitation. 

517. Wheeler ft Woodruff, 280 Madison Ave., New York, N. Y. 
Research staff : T. L. Wheeler, 2 chemical engineers, i mechanical 

engineer, i draftsman, i chemist and i helper. 

Research work : One-half time of 7 on manufacture and regenera- 
tion of bone black, manufacture, use and revivification of decolorizing 
carbons, production and use of gas absorbing carbons, manufacture 
and treatment of carbon black, refining, deodorizing and hydrogena- 
tion of vegetable oils, filtration of water, manufacture of hydrogen, 
electroplating and electro-chemical problems and corrosion of metals 
and metal finishes. 

Equipment: Semi-commercial size apparatus for study of carbon, 
etc. 

518. White Tar Company of New Jersey, Inc., The, 56 Vesey St.. 
New York, N. Y. (Chemicals.) Laboratory at Newark, N. J. 

Research staff : Herbert W. Hamilton and i assistant. 



INDUSTRIAL RESEARCH LABORATORIES 87 

Research work : Approximately one-third time of 2 on purification 
of naphthalene and the development of sanitary products. 

519. Whitten, J. O., Company, The, Cross St., Winchester, Mass. 
(Gelatines.) 

Research staff: G. R. Whitten and 3 assistants. 
Research work : One-half time of 4 on treatment of bone and hide 
preparatory to the manufacture of gelatine. 

520. Wilbur White Chemical Co., The, 62 Temple St., Owego, N. Y. 
Research staff : J. A. Bridgman and 3 chemists. 

Research work: One-half time of 4 on new processes for organic 
intermediates. 

52Z. WUckes, Martin, Wilckes^ Company, Head of Pine St., Camden, 
N. J. (Lampblacks, carbonblacks, etc.) 

Research staff : A. Malmstrom, 4 chemists and i engineer. 

Research work: Full time of i or 2 chemists on phosphoric acid 
compounds and baking powders. 

522. Wiley ft Company, Inc., 904 N. Calvert St., Baltimore, Md. 
(Analytical and consulting chemists.) 

Research staff : Samuel W. Wiley and 7 assistants. 

Research work : Full time of i and part time of others on problems 
connected with the fertilizer industry ; cellulose and paper ; coal, oils 
and coke; beverages. 

523. Wilson ft Co., Chicago, 111. (Packers and provisioners.) Lab- 
oratories at Chicago, 111., Chattanooga, Tenn., Oklahoma City, Okla., 
and Kansas City, Kansas. 

Research staff: L. M. Tolman and 5 assistants. 

Research work : One-half time of 6 on problems connected with 
fermentation, spoilage, etc.; hydrogenation of oils, refining and han- 
dling of oils and by-products. 

524. Winchester Repeating Arms Co., New Haven, Conn. (Rifles, 
shotguns, small arms ammunition, fishing tackle, skates, cutlery, flash- 
lights and tools.) 

Research staff : J. S. Gravely, 4 research chemists, 2 metallurgists 
and metallographists, 2 electrochemists and engineers and 8 assistants. 

Research work: Three-fifths time of 17 on materials and processes 
involved in the manufacture of small arms and ammunition, cutlery, 
tools, hardware and sporting goods, dry batteries, flashlights, etc. 

525. Zinsser ft Co., Hastings-on-Hudson, N. Y. (Manufacturing 
chemists.) 

Research staff: J. S. Zinsser, 5 chemists, i dyer and i analyst. 
Research work : Full time of 8 on anthraquinone color work. 

526. Zobel, Ernst, Company, Inc., 104 2d Ave., Brooklyn, N. Y. (Dis- 
tillers and manufacturers of pine products and coal tar products ; ad- 
hesive pitch, etc.) 

Research staff: F. C. Zobel and 2 assistants. 

Research work: Asphaltum, resin and oil; and coal tar distillate. 



INDUSTRIAL RESEARCH LABORATORIES 



INDEX TO SUBJECT CLASSIFICATION OF LABORATOiaBS 



PAGX 

^B R A S I V E S (carbonindum, 
emery, grinding, polishing, sand- 
paper) 94 

Acetylene, see gas, fuel and illumi- 
nating 109 

Acids, see chemicals, heavy 97 

Acoustics, see sound 118 

Adding machines, see office equip- 
ment 115 

Adhesives (glue, paste, sizing) 94 

Aeronautics, see aircraft 94 

Agitators, see chemical engineering 

equipment 96 

Agricultural equipment and engi- 
neering (land drainage, threshing 

machines, tractors) 94 

Agricultural problems (entomology, 
genetics, pathology, etc See also 

soils and fertilizers) 94,1 18 

Air (air-driven machines, air prod- 
ucts, compressed air, liquid air, 

pneumatics) 94 

Air conditioning (ventilation) 94 

Aircraft and accessories (see also in- 
ternal combustion motors) . . . • 94,1 1 1 
Alcohol, see fuels; see also chemi- 
cals fine (including solvents) and 

liquors 97,108,112 

Alimentary pastes, see foods 107 

Alkalies, see chemicals, heavy 97 

Aluminum, see non-ferrous metals.. 114 
Ammunition, see military and naval 

equipment 114 

Ammeters, see electrical equipment. . 105 
Apparatus and instruments, chemi- 
cal and physical (astronomical in- 
struments, autoclaves, balances, 
compasses, gages, lenses, micro- 
scopes, survejring instruments, tele- 
scopes, transits) 94 

Argon, see gases, except fuel and 

illuminating 109 

Armor, see military and naval equip- 
ment 114 

Artificial ice, see refrigeration 117 

Asphalt, see building materials 95 



PAGE 

Astronomical instruments, see appa- 
ratus and instruments 94 

Autoclaves, see apparatus and in- 
struments 94 

Automobiles, Ke automotive vehicles 95 

Automotive vehicles, equipment and 
accessories (automobiles, tanks, 
tractors, trucks) 95 

BACTERIOLOGY, see chemistry, 

biological 98 

Bakelite, see plastics 116 

Bakery, see foods 107 

Baking powder, see foods 107 

Balances, see apparatus and instru- 
ments 94 

Ball bearings, see mechanics, general 113 
Bearing metals, see non-ferrous 

metals 114 

Bearings, see mechanics, general. ... 113 

Beer, see liquors 112 

Beverages, noo-alcoholic 95 

Biological equipment and suppHes. . . 95 
Biokigy, see chemistry, biological. ... 98 

Biscuit, see foods 107 

Blowers, see chemical engineering 

equipment 96 

Boilers, see fuel utilization; see also 

steam power 109,118 

Boots and shoes, including machin- 
ery, see leather Ill 

Bottle seals, see containers 104 

Brass, see non-ferrous metals 114 

Bricks, see ceramics 96 

Bronze, see non-ferrous metals 114 

Building materials (asphalt, cement, 
concrete, lime, marble, road mate- 
rials, slate. See also iron and 

steel) 95,111 

Butter, see foods 107 

Buttons, see textiles. 119 

By-products from wastes 96 

QABLE, see electrical conununica- 

tion; see also insulation 105,110 

Calorimetry, see heat HO 

Cameras, see photography 116 



INDUSTRIAL RESEARCH LABORATORIES 



» 



PAGE 

Candy, see foods 107 

Cannrng and jireserviiig, see foods.. 107 

Cans, see OQotainers 104 

Carbon, ace chemistry, inorganic; see 

also hibrkants .99,112 

Carbomndmi, see abrasives 94 

Cars, see raibroad equipment 117 

Cash registers, see office equipment. 115 
Casting, see foundry equipment; see 

also plastics 106, 116 

Cast iron, see iron and steel Ill 

Cellulose, see pulp and paper 117 

Cement, see building materials 95 

Centrifuges, see chemical engineermg 

equq>ment 96 

Ceramics (bricks, china, glass, mag- 
nesite, pottery, porcelain, refrac- 
tories) 96 

Charcoal, see fuels 108 

Chemical engineering equipment 
(agitators, blowers, centrifuges, 
compressors, concentrators, con- 
densers, dryers, evaporators, filter 
presses, pulverizers, pumps, sepa* 

rators) 96 

* Chemicals, fine, including solvents.. 97 
Chemicals, heavy (acids, alkalies, 

fungicides, insecticides, salts).... 97 
Chemistry, biological (bacteriology, 

biology) 98 

Chemistry, inorganic (carbon, graph- 
ite, etc.) 99 

Chemistry, mineralogical and geo- 

U^gical (quartz, etc.) 100 

Chemistry, organic (fermentatkm, 

starch, vegetable oils, etc.) 100 

Chemistry, pharmaceutical (cos- 
metics, dentifrice, drugs, disinfec- 
tants, medicines) 102 

China, see ceramics 96 

Chlorine, see gases, except fuel and 

illuminating 109 

Classi6ers, see metallurgy and 

metallography 113 

Gothing, see textiles 119 

Coal, sec fuels 108 

Coke, see fuels 108 

Cold storage, see foods 107 

Omipasses, see apparatus and in- 
struments 94 



PAGE 

Compressed air, see air 94 

Compressors, see chemical engineer- 
ing equipment 96 

Concentration of ores (see also 

chemical engineering equipment )96, 102 
Concentrators, see chemical engi- 
neering equipment 96 

Concrete, see building materials 95 

Condensers, see chemical engineer- 
ing equipment 96 

Condensite, see plastics 116 

Consulting research laboratories 103 

Containers, including bottle seals 

(cans, fiber-board containers, etc.) 104 
Copper, see non-ferrous metals.... 114 

Cordage, see insulation 110 

Cosmetics, see chemistry, pharma- 
ceutical 102 

Cdtton and its products, see textiles. 119 
Cutlery, see machine tools and hard- 
ware 112 

J^^^'^^L equipment and supplies, 
see surgical, dental and hospital 

equipment and supplies 119 

Dentifrice, see chemistry, pharma- 
ceutical 102 

Developers, see photography 116 

Die casting, see foundry equipment. . 108 
Diesel engines, see internal combus- 
tion motors • Ill 

Disinfectants, see chemistry, phar- 
maceutical 102 

Drill-press, see machine tools. ...». 112 
Drugs, see chemistry, pharmaceuti- 
cal 102 

Dryers, see chemical engineering 
equipment; see also paints, oib 

and varnishes. 96, 115 

Dyes, natural and artificial (mks, 
intermediates, pigments, ribbons) . 104 

Dynamite, see explosives 106 

Dynamos, see electric power 105 

£^CONOMIZ£RS, see steam power. 118 
Electrkal communication (cable, 
telegraph, telephone, wireless) .... 105 

Electrical equipment and instruments 
(ammeters, lamps, voltmeters, 
wattmeters) 105 



90 



INDUSTRIAL RESEARCH LABORATORIES 



PAGE 

Electricity, general (economics, util* 
ization) 105 

Electric power (conversion, distribu- 
tion, dynamos, generation, motors, 
power plants, transmission) 105 

Electrochemistry (electrochemical 
processes, electrodes, storage bat- 
teries) 106 

Electrodes, see electrochemistry 106 

Electro-plating 106 

Emery, see abrasives 94 

Enamels, see paints, oils and var- 
nishes 115 

Engines, see steam power; see also 
internal combustion motors... Ill, 118 

Entomology, see agricultural prob- 
lems 94 

Evaporators, see chemical engineer- 
ing equipment 96 

Explosives and explosions (dyna- 
mite, powder, TNT) 106 

Extinguishers, see fire prevention... 107 

pATS, fatty oils and soaps 106 

Fermentation, see chemistry, or- 
ganic 100 

Ferrous alloys, see iron and steel.. Ill 
Fertilizers, see soils and fertilizers.. 118 
Fiber -board containers, see con- 
tainers 104 

Films, see photography 116 

Filter presses, see chemical engineer- 
ing equipment 96 

Filtration 107 

Fire prevention (extinguishers, 

sprinklers) 107 

Fittings, see metal manufactures, 

miscellaneous 113 

Flavoring extracts, see f oodst 107 

Flour, see foods 107 

Foods (alimentary pastes, bakery, 
baking powder, biscuit, butter, 
candy, canning and preserving, 
cold storage, flavoring extracts, 
flour, gelatine, meat and meat 
products, milk, oils, preservatives, 

wheat, yeast, etc.) 107 

Foundry equipment, materials and 
methods (casting, die casting, 
moulding) 108 



PAGB 

Fuels (alcohol, charcoal, coal, coke, 
gasoline, kerosene, oil, peat. See 
also gas, petroleum and wood)... 108 

Fuel utilization (boilers, furnaces, 
gas-producers, radiators, stokers) . 109 

Fungicides, see chemicals, heavy. ... 97 

Furnaces, see fuel utilization 109 

Q-AGES, see apparatus and instru- 
ments 94 

Gas, fuel and illuminating, including 

mantles (acetylene, hydrogen) .... 109 
Gases, except fuel and illuminating, 
including generating apparatus 
(argon, chlorine, helium, neon, 
nitrogen, oxygen, poisonous gases) 109 

Gasoline, see fuels 108 

Gasoline engines, see internal com- 
bustion motors Ill 

Gas-producers, see fuel utilization. . . 109 

(jelatine, see foods 107 

Glass, see ceramics. 96 

Glue, see adhesives 94 

(jold, see non-ferrous metals 114 

Graphite, see chemistry, inorganic; 

see also lubricants 99, 112 

Graphophones, see phonographs and 

graphophones 116 

Grinding, see abrasives 94 

Gutta-percha, see rubber and rubber 
goods 117 

fjAIR, curled, etc 110 

Hardware, see machine tools and 
hardware 112 

Heat (calorimetry, pyrometry, ther- 
mal physics, thermometry) 110 

Heating 110 

Helium, see gases, except fuel and 
illuminating 109 

Hospital equipment and supplies, see 
surgical, dental and hospital equip- 
ment and supplies 119 

Hydraulics (waterworks, water 
power) 110 

Hydrogen, see gas, fuel and illumi- 
nating 109 

JLLUMINATION, electric, gas and 

other 110 

Inks, see dyes 104 



INDUSTRIAL RESEARCH LABORATORIES 



91 



PAGE 

Insecticides, see chemicals, heavy. . . 97 
Insulation, electrical and thermal 
(cable, cordage, non-conductors, 

insulated wire) 110 

Intermediates, see dyes 104 

Internal combustion motors (Diesel 
engines, gasoline engines, motors, 

oil engines) Ill 

Iron and steel (cast iron, ferrous al- 
loys, pipe, wrou{;ht iron) Ill 

KEROSENE, see fuels 108 

X^ACQUERS, see paints, oils and 

varnishes 115 

Lamps, see electrical equipment; see 

also illumination 96, 110 

Land drainage, see agricultural 

equipment and engineering 94 

Lathes, see machine tools 112 

Lead, see non-ferrous metals 114 

Leather and leather goods (boots, 
shoes, including machinery, leather 

substitutes, tanning) Ill 

Lenses, see apparatus and instru- 
ments ; see also light 94, 112 

Light (optical instruments, optics. 

See also illumination) 1 10, 112 

Lime, see building materials 95 

Linen, see textiles 119 

Liquid air, see air 94 

Liquors, fermented and distilled (al- 
cohol, beer, wine) 112 

Locomotives, see railroad equip- 
ment 117 

Lubricants (carbon, graphite, oil, 
petroleum) 112 

lyfACHINE tools and hardware 
(cutlery, drill - presses, lathes, 

planers, shapers) 112 

Magnesite, see ceramics 96 

Magnetism 112 

liiantles, see gas, fuel and illu- 
minating 109 

Marble, see building materials 95 

Marine engineering (ships) 112 

Matches 113 

Meat and meat products, see foods. . 107 



PAcn 

Mechanics, general (bearings, ball, 
roller, etc.) 113 

Medicines, see chemistry, pharma- 
ceutical 102 

Metal manufactures, miscellaneous 
(fittings, pipes, valves) 113 

Metallurgy and metallography, in- 
cluding equipment 113 

Microscopes, see apparatus and in- 
struments 94 

Military and naval equipment (am- 
munition, armor, ordnance, small 
arms, torpedoes) 114 

Mining, general (testing drills, 
ropes, tools; ore dressing) 114 

Motors, see electric power; see also 
internal combustion motors... 105, HI 

Moulding, see foundry equipment; 
see also plastics 108, 116 

Moving-picture equipment, see pho- 
tography 116 

j^ATURAL gums, see rubber and 

rubber goods 117 

Neon, see gases, except fuel and 

illuminating 109 

Nickel, see non-ferrous metals 114 

Nitrates, see soils and fertilizers... 118 
Nitrogen, see gases, except fuel and 

illuminating 109 

Non-conductors, see insulation 110 

Non-ferrous metals (aluminum, 
bearing metals, brass, bronze, cop- 
per, gold, lead, nickel, platinum, 
silver, tin, titanium, zinc) 114 

Office equipment (adding ma- 
chines, cash registers) 115 

Oil engines, see internal combustion 

motors Ill 

Oils, see fats, foods, fuels, lubri- 
cants, paints).. . 106, 107, 108, 112, 115 

Optical instruments, see light 112 

Optics, see light 112 

Ordnance, see military and naval 

equipment 1 14 

Ore dressing, see mining, general. . . 114 
Oxygen, see gases, except fuel and 
illuminating 109 



92 



INDUSTRIAL RESEARCH LABORATORIES 



FACE 

PAINTS, oila and vmraislies (dry- 
ers, enasncU, lacqtwrs, pignentt, 

putty, resins, rust-proofiing) 115 

Pltper, see pulp and paper 117 

Paste, see adhesives 94 

Peat, see fuels 108 

Petroleum and its products (see also 

lubricants) 112, 115 

Phonoffraphs and grapbophones H^^ 

Phosphates, see soils and fertiUaers. 118 
Photograplqr (cameras, developers, 

films, movingwpicture equipment, 

plates) 11<^ 

Pigments, see dyes; see also paints, 

oils and varnishes 104, 115 

Pipe, see iron and steel; see also 

metal manufactures* misc Ill, 113 

Planer, see machine tools 112 

Plant genetics and patfudogy; see 

agrknhural proUema. ^ 

Plastics (bakelite, condenstte, red- 

manol; fat*"^g and moulding of 

phutics) "* 

Plates, see photography H^ 

Platinum, see noii*ferrous metato... H^ 

Pneumatics, see air ^ 

Poisonous gases, see gases, except 

fuel and illuminatmg 1^ 

Polishing, see ahrasivcs •* 

Porcefadn, see ceramics ^ 

Potash, see soils and fertilixers; see 

also chemicals, heavy 118, 97 

Pottery, see ceramics 96 

Powder, see explosives 106 

Power plants, see electric power. ... 105 

Preservatives! see foods 107 

Properties of engineering materials. 116 

Public utilities 117 

Pulp and paper (cellulose) 117 

Pulverisers, see chemical engineer- 
ing equipment 96 

Pumps, see chemical engineering 

equipment 96 

Putty, see paints, oils and varnishes. 115 
Pyrometry, see heat 110 

QUARTZ, see chemistry, mineral- 
ogical and geological 100 



FACE 

RADIATORS, see fuel ultlisatioa. 109 
R adio, see electrical communica** 
tion; see also subatomic phe- 
nomena 105, 118 

Railroad equipment (cars, loeomo- 

tives, signals, etc.) 117 

Razors 117 

Reagenu, see biological equipment 

and supplies 95 

Redmanol, see plastics 116 

Refractories, see ceramics 96 

Refrigeration (artificial ice) 117 

Resins, see paints, oils and varnishes 115 

Ribbons, typewriter, see dyes 104 

Road materials, see building mate- 
rials 95 

Roasters, see metallurgy and metal- 
lography 113 

Rubber and rubber goods, including 
other natural gums (gutta- 
percha) 117 

Rust-proofing, see paints, oils and 
varnishes 116 

Salts, see chemicals, heavy 97 

Sandpaper, see abrasives 94 

Sanitation* sec water, sewage and 

sanitation 119 

Separators, see chemical engineering 

equipment 96 

Sewage, see water, sewage and sani- 
tation 119 

Shaper, see machine tools 112 

Ships, see marine engineering 112 

Shoes and boots, including machin- 
ery, see leather Ill 

Signals, see railroad equipment 117 

Silver, see non-ferrous metals 114 

Sizing, see adhesives; see also pulp 

and paper 94, 117 

Slate, see building materials 95 

Small arms, see military and naval 

equipment 114 

Soaps, see fats 106 

Soils and fertilisers (nitrates, phos- 
phates, potash) 118 

Solvents, see chemicals, fine 97 

Sorghums, see sugar 118 



INDUSTRIAL RESEARCH LABORATORIES 



93 



PAGB 

Sound (acoustics) 118 

Spriaklers, see fire prevention 107 

Starch, see chemistry, ors^nic; see 

also foods 100, 107 

Steam power (boilers, economizers, 
en^es, turbines. See also inter- 
nal combustion motors) 118, 111 

Steel, see iron and steel Ill 

Stokers, see fuel utilization 109 

Storage batteries, see electrochemis- 
try 106 

Subatomic phenomena and radio- 
activity 118 

Sugar (sorghums, syrups) 118 

Surgkal, dental and hospital equip- 
ment and supplies 1 19 

Surveying instruments, see appa- 
ratus and instruments 94 

Syrups, see sugar 118 

fANKS, see automotive vehicles.. 95 
Tanning, see leather llf 

Tar and its products 119 

Telegraph, see electrical communica- 
tion 105 

Telephone, see electrical communica- 
tion 105 

Telescopes, see apparatus and in- 
struments 94 

Textiles, including machinery (but- 
t<»is, clothing, cotton and its prod- 
ucts, linen, wool ; waterproofing) . . 1 19 

Thermal physics, see heat 110 

Thermometry, see heat 110 

Threshing machines, see agricultural 

equipment and engineering 94 

Tin, see non-ferrous metals 114 

Titanium, see non-ferrous metals 114 

TNT, see explosives 106 



PAGE 

Torpedoes, see military and naval 
equipment 114 

Tractors, see agricultuial equip- 
ment and engineering; see also 
automotive vehicles 94, 95 

Transits, see apparatus and instru- 
ments 94 

Trucks, see automotive vehicles 95 

Turbines, see steam power 118 

V^ALVES, see metal manufactures, 
miscellaneous 113 

Varnishes, see paints, oils and var- 
nishes 115 

Vegetable oils, see chemistry, or- 
ganic; see also foods 100, 107 

Ventilation, see air conditioning 94 

Voltmeters, see electrical equip- 
ment 105 

"VV ATER, sewage and sanitation. . 119 
Water power, see hydraulics.. 110 

Waterproofing, see textiles 119 

Wattmeters, see electrical equip- 
ment 105 

Welding, autogenous, gas, electric, 

forge 120 

Wheat, see foods 107 

Wine, see liquors 112 

Wire 120 

Wireless, see electrical communica- 
tion 105 

Wood products, other than cellulose 
and paper (sec also containe 104, 120 

Wool, see textiles 119 

Wrought iron, see iron and steel. ... Ill 



YEAST, see foods 



107 



^INC, see non-ferrous metals 114 



94 



INDUSTRIAL RESEARCH LABORATORIES 



SUBJECT CLASSIFICATION OF LABORATORIES 



Abrasives (carborundum, emery, 
grinding, polishing, sandpaper) 

Armour Glue Works 

Armour Sandpaper Works 

Bausch & Lomb Optical G>. 

Carbortmdum G>mpany, The 

Dorr Company, The 

Gillette Safety Razor Co. 

Kalmus, Comstock & Wescott, Inc. 

Maynard, T. Poole 

Metals & Chemicals Extraction 
Corporation 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

Adhesives (glue, paste, sizing) 

Abbott, William G., Jr. 

Armour Glue Works 

Banks & Craig 

Bausch & Lomb Optical Co. 

Bloede, Victor G., Co. 

Brunswick-Balke-Collender Co. 

Carborundum Company, The 

Cudahy Packing Co., The 

Cumberland Mills 

Dewey & Almy Chemical Com- 
pany 

Dextro Products, Inc. 

Emerson Laboratory 

Feculose Co. of America 

Grosvenor, Wm. M. 

Little, Arthur D., Inc. 

Morris & Company 

National Gum & Mica Co. 

Pfister & Vogcl Leather Co. 

Philadelphia Quartz Company 

Seydel Manufacturing Company 

Skinner, Sherman & Esselen, In- 
corporated 

Swift & Company 

Thac Industrial Products Corp. 

Uniform Adhesive Company, In- 
corporated 

United Chemical and Organic 
Products Co. 

U. S. Food Products Corp. 

United States Glue Co. 

Zobel, Ernst, Company, Inc. 



Agricultural equipment and engi- 
neering (land drainage, thresh- 
ing machines, tractors) 

American Beet Sugar Company 

Banks & Craig 

Minneapolis Steel and Machinery 

Co. 
Utah-Idaho Sugar Company 

Agricultural problems (entomol- 
ogy, genetics, pathology, etc. 
See also soils and fertilizers) 

American Agricultural Chemical 

Company, The 
American Beet Sugar Company 
National Lime Association 
Utah-Idaho Sugar Company 

Air (air - driven machines, air 
products, compressed air, liquid 
air, pneumatics) 

Abbott, William G., Jr. 

Ingersoll-Rand Company 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

Air conditioning (ventilation) 

American Blower Company 
American Radiator Company 
U. S. Testing Ca, Inc. 

Aircraft and accessories (see also 
internal combustion motors) 

Curtiss Aeroplane & Motor Cor- 
poration 
General Motors Research Corpo- 
ration 
Industrial Research Corporation 
Martin, Glen L, Company, The 
Packard Motor Car Company 

Apparatus and instruments, 
chemical and physical (astron- 
omical instruments, autoclaves, 
balances, compasses, gages, 
lenses, microscopes, surveying 



INDUSTRIAL RESEARCH LABORATORIES 



95 



instruments, telescopes, tran- 
sits) 

Baldwin Locomotive Works, The 

Bausch & Lomb Optical Co. 

Brown & Sharpe Mfg. Co. 

Central Scientific Company 

Coming Glass Works 

Cutler-Hammer Mfg. Co., The 

Eastman Kodak Company 

Eimer & Amend 

Electrical Testing Laboratories 

Grosvenor, Wm. M. 

Gurlcy, W. & L. E. 

Kellogg Switchboard and Supply 
Co, 

Kilboume & Qark Manufacturing 
Company 

Keu£Fel & Esser Co. 

Mojonnier Bros. Co. 

Munn, W. Faitoute 

Pyrolectric Instrument Company 

Riverbank Laboratories 

Sangamo Electric Company 

Scientific Instrument and Electri- 
cal Machine Company, The 

Tolhurst Machine Works 

Wallace & Tieman Co., Inc. 

Waltham Watch Company 

Automotive vehicles, equipment 
and accessories (automobiles, 
tanks, tractors, trucks) 

Abbott. William G., Jr. 
Boyer Chemical Laboratory Com- 
pany 
Champion Ignition Company 
Diamond Chain & Manufacturing 

Company 
Dodge Brothers 
Electrical Testing Laboratories 
Fansteel Products Company, Inc 
General Motors Research Corpo- 
ration 
Holt Manufacturing Company, The 
Industrial Research Corporation 
Lunkenheimer Co., The 
Minneapolis Steel and Machinery 

Co. 
Northwestern Chemical Co., The 
Packard Motor Car Company 



Pierce- Arrow Motor Car Com- 
pany, The 

Stewart- Warner Speedometer 
Corporation 

Studebaker Corporation, The 

Wallace & Tieman Co., Inc. 

Beverages, non-alcoholic 

California Fruit Growers Ex- 
change 

Dehls & Stein 

Industrial Chemical Institute of 
Milwaukee 

Industrial Testing Laboratories 

Lennox Chemical Co., The 

Nowak Chemical Laboratories 

Schwarz Laboratories 

Skinner, Sherman & Esselen, In- 
corporated 

U. S. Food Products Corp. 

Wahl-Henius Institute, Incorpo- 
rated 

Biological equipment and supplies 

Baker, J. T., Chemical Co. 
Beebe Laboratories, Inc 
Central Scientific Company 
Coleman & Bell Company, The 
Dean Laboratories, Inc. 
Digestive Ferments Co. 
Eimer & Amend 
Lilly, Eli, and Company 
Mulford, H. K., Company 
Swan-Myers Company 

Building materials (asphalt, ce- 
ment, concrete, lime, marble, 
road materials, slate. See also 
iron and steel) 

Barber Asphalt Paving Company, 

The 
Beaver Board Companies, The 
Borrowman, George 
Conwell, W. L., ft Co., Inc. 
Hunt, Robert W., and Co. 
Institute of Industrial Research, 

The 
Interocean Oil Company, The 
Lewis, F. J., Manufacturing Co. 
Maynard, T. Poole 



96 



INDUSTRIAL RESEARCH LABORATORIES 



National Lime Association 

Pennsylvania Railroad G>mpany» 
The 

Richardson Company, The 

Skinner, Sherman ft Esselen, In- 
corporated 

Standard Oil Company (New 
Jersey) 

Structural Materials Research 
Laboratory 

Toch Brothers 

Weld and Liddell 

By-products from wastes 

Abbott, William G., Jr. 

Anaconda Copper Mining Co. 

California Fruit Growers Ex- 
change 

Davison Chemical Company, The 

Emerson Laboratory 

Federal Products Company, The 

Grosvenor, Wm. M. 

Harrison Mfg. Co., The 

Kidde, Walter, & Company, In- 
corporated 

Koppers Company, The 

Lakeview Laboratories 

Laucks, L F., Inc. 

Ljrster Chemical Company, Inc. 

Maynard, T. Poole 

Morris ft Company 

Research Corporation 

Scott, Ernest, ft Company 

Stamford Dyewood Company 

Swenson Evaporator Company 

Teeple, John E. 

Thac Industrial Products Corp. 

Vacuum Oil Company, Incorpo- 
rated 

Weld and Liddell 

Western Precipitation Company 

Wheeler ft Woodru£F 

White Tar Company of New 
Jersey, Inc., The 

Wilson ft Ca 

Ceramics (bricks, china, glass, 
magnesite, pottery, porcelain, 
refractories) 

American Window Glass Co. 
Anaconda Copper Mining Co. 



Andrews, A. B. 

Babcock ft Wilcox Co., The 

Bausdi ft Lomb Optical Co. 

Beaver Falls Art Tile Company 

Buckeye Qay Pot Co. 

Carborundum Company, The 

Celite Products Company 

Champion Porcelain Company 

Coming Glass Works 

Dorite Manufacturing Company, 
The 

Ellis-Foster Company 

FitzGerald Laboratories, Inc., The 

Fry, H. C, Glass Company 

Glass Container Association of 
America 

Harbison-Walker Refractories 
Company 

Kalmus, Comstock ft Wescott, Inc. 

Keuffel ft Esser Co. 

Koppers Company, The 

Kraus Research Laboratories, Inc. 

Laclede-Christy Clay Products 
Company 

Little, Arthur D., Inc. 

Maynard, T. Poole 

National Laboratories, The 

National Lamp Works of General 
Electric Company 

Pfaudler Co., The 

Pittsburgh Testing Laboratory 

Ransom ft Randolph Co., The 

Roessler ft Hasslacher Chemical 
Company, The 

Spencer Lens Company 

Thac Industrial Products Corp. 

Titanium Alloy Manufacturing Co. 

Union Carbide and Carton Re- 
search Laboratories, Inc. 

Waltham Watch Company 

Weld and Liddell 

Western Gas Construction Com- 
pany, The 

Chemical engineering equipment 
(agitators, blowers, centrifuges, 
compressors, concentrators, 
condensers, dryers, evapora- 



INDUSTRIAL RESEARCH LABORATORIES 



97 



tors, filter presses, pulverizers, 
pumps, separators) 

Abb^ Engineering G)mpany 

Abbott, William G.. Jr. 

American Blower Company 

Anaconda Copper Mining Co. 

Andrews, A. B. 

Bethlehem Shipbuilding Corpora- 
tion, Ltd. 

Bu£Falo Fomidry and Machine Ca 

Cramp, William, ft Sons Ship ft 
Engine Building Co., The 

Deister Concentrator Company, 
The 

DeLaval Separator Co., The 

Dorr Company, The 

IngersoU-Rand 'Company 

International Filter Co. 

Oliver Continuous Filter Co. 

Scott, Ernest, ft Company 

Sperry, D. R., ft Co. 

Swenson Evaporator Company 

Tolhurst Machine Works 

United States Bronze Powder 
Works, Inc. 

Wayne Oil Tank and Pump Co. 

Western Gas Construction Com- 
pany, The 

Chemicals, fine, including sol- 
vents 

Abbott Laboratories, The 
Atlantic Dyestuff Company 
Baker, J. T., Chemical Co. 
Barrett Company, The 
Calco Chemical Company, The 
Cams Chemical Company 
Central DyestuflF and Chemical Co. 
Central Scientific Company 
Chemical Economy Company 
Chemical Products Company 
Coleman ft Bell Company, The 
Cosmos Chemical Co., Inc. 
Dehls ft Stein 
Digestive Ferments Co. 
Eastman Kodak Company 
Eppley Laboratory 
Federal Products Company, The 
Florida Wood Products Co. 
General Chemical Company 



Harrison Mfg. Co., The 

Heyden Chemical Company of 
America, Inc. 

Hsmson, Westcott & Dunning 

Lakeview Laboratories 

Lehn ft Fink, Inc. 

Lemoine, Pierre, Cie., Inc. 

Lindsay Light Company 

Long & Co., Inc. 

Lyster Chemical Company, Inc. 

Mallinckrodt Chemical Works 

McKesson ft Robbins, Incorporated 

McLaughlin Gormley King Co. 

Merck ft Co. 

Monroe Drug Company 

Monsanto Chemical Works 

Newark Industrial Laboratories 

New York Quinine ft- Chemical 
Works, Incorporated, The 

Norveil Chemical Corporation, The 

Ohio Fuel Supply Company, The 

Palmolive Company, The 

Parke, Davis ft Company 

Peet Bros. Mfg. Co. 

Pfizer, Chas., ft Co., Inc. 

Pharma-Chemical Corporation 

Powers - Weightman - Rosengarten 
Company, The 

Radium Company of Colorado. 
Inc., The 

Radhim Limited, U. S. A. 

Roessler ft Hasslacher Chemical 
Company, The 

Seydel Manufacturing Company 

Sharp & Dohme 

Special Chemicals Company 

Squibb, K R., ft Sons 

Thac Industrial Products Corp. 

T. M. & G. Chemical Co. 

Tower Manufacturing Co., Inc. 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

U. S. Industrial Alcohol Company 

Universal Aniline Dyes and Chem- 
ical Co. 

Wilbur White Chemical Co., The 

Chemicals, heavy (acids, alkalies, 
fungicides, insecticides, salts) 
American Cyanamid Company 
American Trona Corporation 



98 



INDUSTRIAL RESEARCH LABORATORIES 



Anaconda Copper Mining Co. 
Ansul Chemical Company 
Armour Ammonia Works 
Atlas Powder Ca 
Bowker Insecticide Company 
Brown Company 

Buchanan, C. G., Chemical Com- 
pany 
Butterworth-Judson Corporation 
California Fruit Growers Ex- 
change 
Carborundum Company, The 
Carus Chemical Company 
Charlotte Chemical Laboratories, 

Inc. 
Condensite Company of America 
Davison Chemical Company, The 
Detroit Testing Laboratory, The 
Drackett, P. W., & Sons Co., The 
du Pont, K I., de Nemours ft 

Company 
Eagle-Picher Lead Company, The 
Eastern Manufacturing Company 
Federal Phosphorus Company 
General Chemical Company 
Glidden Company, The 
Grasselli Chemical Company 
Great Western Electro-Chemical 

Company 
Grosvenor, Wm. M. 
Harrison Mfg. Co., The 
Hooker Electrochemical Company 
Industrial Chemical Institute of 

Milwaukee 
Maas, A. R., Chemical Company 
Mallinckrodt Chemical Works 
Mathieson Alkali Works, Inc., The 
McLaughlin Gormley King Co. 
Merrimac Chemical Company 
Metals & Chemicals Extraction 

Corporation 
Meyer, Theodore 
Monsanto Chemical Works 
National Lead Company 
Naugatuck Chemical Company, 

The 
New Jersey Zinc Company, The 
New York Quinine ft Chemical 

Works, Incorporated, The 
Norvell Chemical Corporation, The 
Peet Bros. Mfg. Co. 



Pennsylvania Salt Manufacturing 
Co. 

Philadelphia Quartz Company 

Pittsburgh Plate Glass Co. 

Powers - Weightman - Rosengartcn 
Company, The 

Pure Oil Company, Kanawha River 
Salt and Chemical Division 

Riches, Piver ft Co. 

Rodman Chemical Company 

Roessler & Hasslacher Chemical 
Company, The 

Saginaw Salt Products Co. 

Seydel Manufacturing Company 

Solvay Process Company, The 

Swen^pn Evaporator Company 

Titanium Pigment Co., Inc. 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

United Chemical and Organic 
Products Co. 

United States Metals Refining Co. 

Utah-Idaho Sugar Company 

Victor Chemical Works 

Welsbach Company 

Wilckes, Martin, Wilckes Com- 
pany 

Chemistry, biological (bacteri- 
ology, biology) 

• 

Abbott Laboratories, The 
American Beet Sugar Company 
American Hominy Company 
American Institute of Baking 
Banks & Craig 
Beebe Laboratories, Inc. 
Bridgeman-Russell Company 
Coleman & Bell Company, The 
Dean Laboratories, Inc. 
Dearborn Chemical Company 
Dehls ft Stein 
Digestive Ferments Co. 
Freed, H. E, Co., The 
Gallun, A. F., ft Sons Co. 
Glass Container Association of 

America 
Hochstadter Laboratories 
Industrial Testing Laboratories 
Kolynos Co., The 
Lehn & Fink, Inc. 



INDUSTRIAL RESEARCH LABORATORIES 



99 



Merrell-Soale Laboratory 

Metz, H. A., Laboratories, Inc. 

Miner Laboratories, The 

Morris & G)mpany 

Mulford, H. K., Company 

National Canners Association 

National Laboratories, The 

New York Quinine & Chemical 
Works, Incorporated, The 

Parke, Davis & Company 

Pease Laboratories 

Physicians and Surgeons Labora- 
tory 

Porro Biological Laboratories 

Schwarz Laboratories 

Seydel Manufacturing Company 

Skinner, Sherman & Esselen, In- 
corporated 

Special Chemicals Company 

Sprague, Warner & Company 

Squibb, E. R., & Sons 

Swan-Myers Company 

Takamine Laboratory, Inc. 

Telling-Beele Vernon Company, 
The 

United States Glue Co. 

U. S. Industrial Alcohol Company 

Upjohn Company, The 

Weston & Sampson 

White Tar Company of New Jer- 
sey, Inc., The 

Wilson & Co. 

Chemistry, inorganic (carbon, 
graphite, etc.) 

Acheson Graphite Company 
American Agricultural Chemical 

Company, The 
American Chemical Paint Com- 
pany 
American Cyanamid Company 
American Trona Corporation 
Ansbacher, A. B., & Company 
Ansul Chemical Company 
Atlas Powder Co. 
Baker ft Co., Inc. 
Beaver Falls Art Tile Company 
Borrowman, George 
Borromite Co. of America, The 
Bowker Insecticide Company 



Brown Company 

Buchanan, C. G., Chemical Com- 
pany 

Burdett Manufacturing Company 

Carus Chemical Company 

Celite Products Company 

Charlotte Chemical Laboratories, 
Inc. 

Chase Metal Works 

Childs, Charles M., & Co., Inc. 

Condensite Company of America 

Dearborn Chemical Company 

Detroit Testing Laboratory, The 

Diamond Match Co., The 

Dorite Manufacturing Company, 
The 

Drackctt, P. W., & Sons Co., The 

Eagle-Picher Lead Company, The 

Eimer & Amend 

Emerson Laboratory 

FitzGerald Laboratories, Inc. 

General Chemical Company 

Glysyn Corporation, The 

Grasselli Chemical Company 

Great Western Electro-Chemical 
Company 

Harrison Mfg. Co., The 

Heyden Chemical Company of 
America, Inc. 

Hochstadter Laboratories 

Hooker Electrochemical Company 

Industrial Chemical Institute of 
Milwaukee 

Jaques Manufacturing Company 

Kalmus, Comstock & Wescott, Inc 

Laucks, I. F., Inc. 

Lee & Wight 

Lennox Chemical Co., The 

Lindsay Light Company 

Maas, A. R., Chemical Company 

Mallinckrodt Chemical Works 

McNab & Harlin Manufacturing 
Co. 

Merck & Co. 

Merrimac Chemical Company 

Metals & Chemicals Extraction 
Corporation 

Mineral Refining & Chemical Cor- 
poration 

Munning, A. P., & Co. 



100 



INDUSTRIAL RESEARCH LABORATORIES 



National Aniline & Qiemical Com- 
pany, Incorporated 

National Laboratories, The 

National Lead Company 

National Lime Association 

Niles Tool Worics Company, The 

Northwestern Chemical Co., The 

Norvell Chemical Corporation, The 

Pennsylvania Salt Manufacturing 
Co. 

Permutit Company, The 

Perolin Company of America, The 

Pfizer, Chas., & Co., Inc. 

Pittsburgh Testing Laboratory 

Pure Oil Company, Kanawha River 
Salt and Chemical Division 

Pyro-Non Paint Co., Inc. 

Radium Company of Colorado^ 
Inc., The 

Radium Limited, U. S. A. 

Ransom ft Randolph Co., The 

Rhode Island Malleable Iron 
Works 

Riches, Piver ft Co. 

Rodman Chemical Company 

Speer Carbon Company 

Squibb, E. R., ft Sons 

Teeple, John E. 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

United States Bronze Powder 
5 Works, Inc. 

United States Smelting, Refinuig 
ft Mining Company 

Wadsworth Watch Case Ca, In- 
corporated, The 

Waltham Watch Company 

Wedge Mechanical Furnace Com- 
pany 

Weld and Liddell 

Wheeler ft Woodruff 

White Tar Company of New Jer- 
sey, Inc., The 

Wilckes, Martin, Wilckes Com- 
pany 

Wiley ft Company, Inc. 

Chemistry, mineralogical and 
geological (quartz, etc.) 

Celite Products Company 



Charlotte Chemical Laboratories, 
Inc. 

Hirsch Laboratories, Inc., The 

Lee ft Wight 

Little, Arthur D., Inc. 

Philadelphia Quartz Company 

United States Smelting, Refining 
& Mining Company 

Wedge Mechanical Furnace Com- 
pany 

Western Research Corporation, In- 
corporated 

Chemistry, organic (fermenta- 
tion, starch, vegetable oils, etc.) 

American Beet Sugar Company 
American Chemical and Manufac- 
turing Corporation 
American Chemical Paint Com- 
pany 
American Cyanamid Company 
American Dianuilt Company 
American Hominy Company 
Atlantic Dyestuff Company 
Avri Drug ft Chemical Company, 

Inc. 
Barrett Company, The 
Beckman and Linden Engineering 

Corporation 
Bennetts' Chemical Laboratory 
Betz, Frank S., Company 
Bloede, Victor G., Co. 
Brown Company 
Calco Chemical Company, The 
California Fruit Growers Ex- 
change 
California Ink Company, Inc. 
Cams Chemical Company 
Central Dyestuff and Chemical Co. 
Charlotte Chemical Laboratories, 

Inc. 
Chemical Economy Company 
Chemical Products Company 
Chemical Service Laboratories, 

Inc., The 
Coleman ft Bell Company, The 
Com Products Refining Company 
Cosmos Chemical Co., Inc. 
Cudahy Packing Co., The 
Davis Chemical Products, Inc. 



INDUSTRIAL RESEARCH LABORATORIES 



101 



Dearborn Chemical Company 

Defals ft Stein 

Detroit Testing Laboratory, The 

Dewey ft Almy Chemical C6mi»any 

Dextro Products, Inc 

Dicks David Company, Incorpo- 
rated 

Digestive Ferments Ca 

du Pont, £. I., de Nemours ft 
Company 

Dye Products & Chemical Com- 
pany, Inc. 

Eastman Kodak Company 

Eimer ft Amend 

Ellis-Foster Company 

Emerson Laboratory 

Feculose Co. of America 

Federal Products Company, The 

Foster-Heaton Company 

Garfield Aniline Works, Inc 

General Bakelite Company 

General Chemical Company 

Glysyn Corporation, The 

Grasselli Chemical Company 

Harrison Mfg. Co^ The 

Heap, William, ft Sons 

Heyden Chemical Company of 
America, Inc. 

Hirsch Laboratories, Inc, The 

Hochstadter Laboratories 

Hynson, Westcott ft Dunning 

Industrial Chemical Institute of 
Milwaukee 

Industrial Testing Laboratories 

Lakeview Laboratories 

Laucks, I. F., Inc. 

Lee ft Wight 

Lehn ft Fink, Inc 

Lemoine, Pierre, Cie., Inc 

Lewis, F. J., Manufacturing Co. 

Long ft Co., Inc. 

Mallinckrodt Chemical Works 

May Chemical Works 

M. B. Chemical Co., Inc. 

McLaughlin Gormley King Co. 

Merck & Co. 

Metz, H. A., Laboratories, Inc 

Miner Laboratories, The 

Monroe Drug Company 

Musher and Company, Incorpo- 
rated 



National Aniline ft Chemical Com- 
pany, Incorporated 
National Laboratories, The 
New York Quebracho Extract 

Company, Incorporated 
New York Quinine & Chemical 

Works, Incorporated, The 
New York Sugar Trade Labora- 
*tory, Inc, The 

Norvell Chemical Corporation, The 
Nulomoline Company, The 
Ohio Fuel Supply Company. The 
Ohio Grease Co., The 
Palmolive Company, The 
Pfizer, Chas., ft Co., Inc. 
Pharma-Chemical Corporation 
Pittsburgh Testing Laboratory 
Procter & Gamble Co., The 
Pure Oil Company, Moore Oil and 

Refining Company Division 
Quinn, T. H., & Company 
Radiant Dye ft Color Works 
Schaeffer Brothers ft Powell 

Manufacturing Company 
Schwarz Laboratories 
Sears, Roebuck and Co. 
Seydel Manufacturing Company 
Sharp ft Dohme 

Skinner, Sherman & Esselen, In- 
corporated 
Southern Cotton Oil Company, 

The 
Special Chemicals Company 
Squibb, E. R., ft Sons 
Stamford Dye wood Company 
Standard Oil Company (New 

Jersey) 
Standard Oil Company of Indiana 
Swan-Myers Company 
Swift ft Company 
Takamine Laboratory, Inc. 
Teeple, John K 
Telling-Belle Vernon Company, 

The 
T. M. ft G. Chemical Ca 
Tower Manufacturing Co., Inc 
Ultro Chemical Corporation 
U. S. Food Products Corp. 
U. S. Industrial Alcohol Company 
Universal Aniline Dyes and Chem- 
ical Co. 



102 



INDUSTRIAL RESEARCH LABORATORIES 



Utility Color & Chemical Co^ The 

Van Schaack Brothers Chemical 
Works, Inc. 

Wallace, Joseph H., & Co. 

Wells, Raymond 

Western Gas Construction Com- 
pany, The 

Western Sugar Refinery 

White Tar Company of New Jer- 
sey, Inc., The 

Whitten, J. O., Company, The 

Wilbur White Chemical Co., The 

Zinsser & Co. 

Zobel, Ernst, Company, Inc. 

Chemistry, pharmaceutical (cos- 
metics, dentifrice, drug^s, disin- 
fectants, medicines) 

Abbott Laboratories, The 

Avri Drug & Chemical Company, 

Inc. 
Betz, Frank S., Company 
Bowker Insecticide Company 
Boyer Chemical Laboratory Com- 
pany 
Calco Chemical Company, The 
Carus Chemical Company 
Caulk, L. D., Company, The 
Central Dyestuff and Chemical Co. 
Corn Products Refining Company 
Cudahy Packing Co., The 
Dean Laboratories, Inc. 
Heinrich Laboratories of Applied 

Chemistry 
Heyden Chemical Company of 

America, Inc. 
Hirsch Laboratories, Inc., The 
Hoehstadter Laboratories 
Hynson, Wcstcott & Dunning 
Industrial Chemical Institute of 

Milwaukee 
Industrial Testing Laboratories 
Johnson & Johnson 
Kolynos Co., The 
Lakeview Laboratories 
Larkin Co. 
Lehn & Fink, Inc. 
Lilly, Eli, and Company 
Long & Co., Inc. 
Lyster Chemical Company, Inc. 



MacAndrews ft Forbes Company 
Mallinckrodt Chemical Works 
McKesson & Robbins, Incorpo- 
rated 
McLaughlin Gormley King Co. 
Meigs, Bassett & Slaughter, Inc. 
Merck ft Co. 

Merrell, Wm. S., Company, The 
Metz, H. A. Laboratories, Inc. 
Meyer, Theodore 
Milliken, John T., and Co. 
Miner Laboratories, The 
Monsanto Chemical Works 
Mulford, H. K., Company 
Newark Industrial Laboratories 
New York Quinine ft Chemical 

Works, Incorporated, The 
Norvell Chemical Corporation, The 
Parke, Davis ft Company 
Pfizer, Chas., ft Co., Inc. 
Pharma-Chemical Corporation 
Physicians and Surgeons Labora- 
tory 
Pittsburgh Testing Laboratory 
Sears, Roebuck and Co. 
Seydel Manufacturing Company 
Sharp & Dohme 
Squibb, E. R., ft Sons 
Standard Oil Company (New 

Jersey) 
Swan-Myers Company 
Takamine Laboratory, Inc. 
Thac Industrial Products Corp. 
Union Carbide and Carbon Re- 
search Laboratories, Inc. 
United Drug Company 
U. S. Food Products. Corp. 
Upjohn Company, The 
Warner, William R., & Company, 

Incorporated 
White Tar Company of New Jer- 
sey, Inc., The 
Wilckes, Martm, Wilckes Com- 
pany 
Zinsser & Co. 

Concentration of ores (see also 
chemical engineering equip- 
ment) 

Anaconda Copper Mining Co. 



INDUSTRIAL RESEARCH LABORATORIES 



103 



Deister Concentrator Company, 
The 

Dorr Company, The 

General Engineering Company, 
Incorporated, The 

Grasselli Chemical Company 

Grosvenor, Wm. M. 

James Ore Concentrator Co. 

Maynard, T. Poole 

Mesabi Iron Company 

National Laboratories, The 

Richards & Locke 

Taggart and Yerxa 

United States Smelting, Refining 
& Mining Company 

Utah Copper Company 

Wedge Mechanical Furnace Com- 
pany 

Western Research Corporation, 
Incorporated 

Consulting research laboratories 

Abbott, William G., Jr. 

Andrews, A. B. 

Babcock Testing Laboratory 

Banks & Craig 

Beckman and Linden Engineering 
Corporation 

Beebe Laboratories, Inc. 

Bennetts' Chemical Laboratory 

Borrowman, George 

Cabot, Samuel, Inc. 

Case Research Laboratory 

Chemical Service Laboratories, 
Inc., The 

Cleveland Testing Laboratory Co., 
The 

Commercial Testing and Engi- 
neering Co. 

Conwell, E. L., & Co., Inc. 

Dean Laboratories, Inc. 

Detroit Testing Laboratory, The 

Dorr Company, The 

Dunham, H. V. 

Durfee, Winthrop C. 

Electrical Testing Laboratories 

Electrolabs Company, The 

Ellis-Foster Company 

Emerson Laboratory 

Eppley Laboratory, The 



Eustis, F. A. 

Fahy, Frank P. 

FitzGerald Laboratories, Inc., The 

Fort Worth Laboratories 

General Engineering Company, In- 
corporated, The 

Gray Industrial Laboratories, The 

Grosvenor, Wm. M. 

Hayes, Hammond V. 

Heinrich Laboratories of Applied 
Chemistry 

Hirsch Laboratories, Inc., The 

Hochstadter Laboratories 

Howard Wheat and Flour Testing 
Laboratory, The 

Hunt, Robert W., and Co. 

Industrial Chemical Institute of 
Milwaukee 

Industrial Research Corporation 

Industrial Research Laboratories 

Industrial Testing Laboratories 

Institute of Industrial Research, 
The 

Kalmus, Comstock & Wescott, 
Inc. 

Kidde, Walter, & Company, In- 
corporated 

Kraus Research Laboratories 

Lakeview Laboratories 

Laucks, I. F., Inc. 

Lee & Wight 

Lincoln, E. S., Inc. 

Little, Arthur D., Inc. 

Littlefield Laboratories Co. 

Lockhart Laboratories 

Maynard, T. Poole 

Mcllhiney, Parker C. 

Meigs, Bassett & Slaughter, Inc. 

Miner Laboratories, The 

Munn, W. Faitoute 

National Laboratories, The 

Newark Industrial Laboratories 

New York Sugar Trade Labora- 
tory, Inc., The 

Pease Laboratories 

Pettee, Charles L. W., Labora- 
tories of 

Physicians and Surgeons Labora- 
tory 

Pittsburgh Testing Laboratory 



104 



INDUSTRIAL RESEARCH LABORATORIES 



Porro Biological Laboratories 
Porter, Horace C. 
Quinn, T. H., & G)mpany 
Research Corporation 
Richards & Locke 
Riverbank Laboratories 
Rubber Trade Laboratory, The 
Sabine, Wallace Qement, Labora- 
tory 

Schwarz Laboratories 

Skinner, Sherman & Esselen, In- 
corporated 

Souther, Henry, Engineering G>., 
The 

Structural Materials Research 
Laboratory 

Taggart and Yerxa 

Takamine Laboratory, Inc. 

Teeple, John E. 

Wahl-Henius Institute, Incorpo- 
rated 

Weld and Liddell 

Wells, Raymond 

Western Precipitation G>mpany 

Western Research Corporation, 
Incorporated 

Weston & Sampson 

Wiley & Company, Inc. 

Containers, including bottle seals 
(cans, fiber-board containers, 
etc.) 

American Can Company 

Bond Manufacturing Corporation 

Chicago Mill and Lumber Com- 
pany 

Dewey & Almy Chemical Com- 
pany 

Glass Container Association of 
America 

Lehn & Fink, Inc. 

National Association of Corru- 
gated and Fibre Box Manufac- 
turers, The 

National Canners Association 

Package Paper and Supply Cor- 
poration 

Vacuum Oil Company, Incorpo- 
rated 

Wheeler & Woodruff 



Dyes, natural and artificial (inks, 
intermediates, pigments, rib- 
bons) 

Amoskeag Manufacturing Com- 
pany 

Arlington Mills 

Atlantic Dyestuff Company 

Ault & Wiborg Company, The 

Banks & Craig 

Butterworth-Judson Corporation 

Calco Chemical Company, The 

California Ink Company, Inc. 

Central Dyestuff and Chemical Co. 

Coleman ft Bell Company, The 

Dicks David Company, Incorpo- 
rated 

du Pont, E. I., de Nemours & 
Company 

Durfee, Winthrop C. 

Dye Products & Chemical Com- 
pany, Inc. 

Eastern Finishing Works, Inc. 

Eavenson & Levering Co. 

Emerson Laboratory 

Foster-Heaton Company 

Garfield Aniline Works, Inc. 
Garrison Mfg. Co., The 
Grasselli Chemical Company 
Grosvenor, Wm. M. 
Hirsch Laboratories, Inc., The 
Hodcer Electrochemical Company 
Klearflax Linen Rug Company 
Little, Arthur D., Inc. 
Lockhart Laboratories 
Long & Co., Inc. 
MacAndrews & Forbes Company 
May Chemical Works 
M. B. Chemical Co., Inc. 
Merrimac Chemical Company 
Monroe Drug Company 
Monsanto Chemical Works 
Morrill, Gea H., Co. 
National Aniline & Chemical Com- 
pany, Incorporated 
National Laboratories, The 
Naugatuck Chemical Company, 

The 
Newark Industrial Laboratories 
Northwestern Chemical Co., The 
Oliver Continuous Filter Co. 



INDUSTRIAL RESEARCH LABORATORIES 



105 



Palatine Aniline and Chemical 
Corporation 

Peerless Color Company 

Pharma-Chemical Corporation 

Pittsburgh Plate Glass Co. 

Radiant Dye & Color Works 

Reliance Aniline & Chemical Ca, 
Incorporated 

Sears, Roebuck and Co. 

Seydel Manufacturing Company 

Stamford Dyewood Company 

Sun Chemical & Color Co. 

T. M. & G. Chemical Co. 

Tower Manufacturing Co., Inc. 

Ultro Chemical Corporation 

U. S. Testing Co., Inc. 

Universal Aniline Dyes and Chem- 
ical Co. 

Utility Color & Chemical Co., The 

White Tar Company of New Jer- 
sey, Inc., The 

Wilbur White Chemical Ca, The 

Zinsser & Co. 

Electrical communication (cable, 
telegraph, telephone, wireless) 

American Radio and Research 
Corporation 

Belden Manufacturing Company 

Coming Glass Works 

General Electric Company 

Hayes, Hammond V. 

Industrial Research Corporation 

Kellogg Switchboard and Supply 
Co. 

Kilbourne & Qark Manufacturing 
Company 

Munn, W. Faitoute 

Western Electric Company, Incor- 
porated 

Electrical equipment and instru- 
ments (ammeters, lamps, volt- 
meters, wattmeters) 

Abbott, William G., Jr. 

Allen-Bradley Co. 

American Radio and Research 

Corporation 
Commonwealth Edison Company 
Cooper Hewitt Electric Company 



Coming Glass Works 
Cutler-Hammer Mfg. Co., The 
Edison, Thomas A., Laboratory 
Electrical Testing Laboratories 
Fansteel Products Company, Inc. 
General Electric Company 
Hoskins Manufacturing Company 
Kilbourne & Clark Manufacturing 

Company 
Kellogg Switchboard and Supply 

Ca 
Leeds & Northrup Company 
Munn, W. Faitoute 
National Lamp Works of General 

Electric Company 
Pyrolectric Instrument Company 
Sangamo Electric Company 
Scientific Instrument and Electri- 
cal Machine Company, The 
Speer Carbon Company 
Union Carbide and Carbon Re- 
search Laboratories, Inc. 
Western Electric Company, Incor- 
porated 
Westinghouse Electric & Manu- 
facturing Company 
Westinghouse Lamp Co. 

« 

Electricity, general (economics, 
utilization) 

Belden Manufacturing Company 
Cutler-Hammer Mfg. Co., The 
Edison, Thomas A., Laboratory 
Electrical Testing Laboratories 
General Electric Company 
Hayes, Hammond V. 
Kilbourne & Clark Manufacturing 

Company 
Western Electric Company, Incor- 
porated 
Westinghouse Electric & Manu- 
facturing Company 

Electric power (conversion, dis- 
tribution, dynamos, generation, 
motors, power plants, trans- 
mission) 

American Radio and Research 

Corporation 
Commonwealth Edison Company 



106 



INDUSTRIAL RESEARCH LABORATORIES 



Cutlcr-Hammcr Mfg. Co., The 
Detroit Edison Company, The 
General Electric Company 
General Motors Research Corpo- 
ration 
Imperial Belting Company 
Industrial Research Corporation 
Lincoln, E. S., Inc. 
S. K. F. Industries, Inc. 
Union Carbide and Carbon Re- 
search Laboratories, Inc. 
Vesta Battery Corporation 

Electrochemistry (electrochem- 
ical processes, electrodes, stor- 
age batteries) 

Acheson Graphite Company 
Anaconda Copper Mining Co. 
Andrews, A. B. 
. Beckman and Linden Engineering 
Corporation 
Carborundum Company, The 
Eastern Manufacturing Company 
Edison, Thomas A., Laboratory 
Electro Chemical Company, The 
Elcctrolabs Company, The 
Eppley Laboratory 
FitzGerald Laboratories, Inc., The 
Grasselli Chemical Company 
Great Western Electro-Chemical 

Company 
Grosvenor, Wm. M. 
Hirsch Laboratories, Inc., The 
Hooker Electrochemical Company 
International Silver Company 
Kidde, Walter, & Company, In- 
corporated 
Leeds & Northrup Company 
Littlefield Laboratories Co. 
Mathieson Alkali Works, Inc., The 
Mcllhiney, Parker C. 
National Lamp Works of General 

Electric Company 
Prest-O-Lite Co., Inc., The 
Riverbank Laboratories 
Speer Carbon Company 
Union Carbide and Carbon Re- 
search Laboratories, Inc. 
United States Smelting, Refining 
& Mining Company 



Vesta Battery Corporation 
Weld and Liddell 

Electro-plating 

Bausch & Lomb Optical Co. 

Columbia Graphophone Manufac- 
turing Company 

Crompton & K n o w 1 e s Loom 
Works 

Gillette Safety Razor Co. 

Gurley, W. & L. E. 

Munn, W. Faitoute 

Munning, A. P., & Co. 

Sears, Roebuck and Co. 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

Waltham Watch Company 

Wheeler & Woodruff 

Explosives and explosions (dyna- 
mite, powder, TNT) 

Atlas Powder Co. 

Barrett Company, The 

Davis Chemical Products, Inc. 

du Pont, E. I., de Nemours & 

Company 
Grasselli Chemical Company 
Hercules Powder Co. 
Remington Arms, Union Metallic 

Cartridge Company 
Van Schaack Brothers Chemical 

Works, Inc. 

Fats, fatty oils and soaps 

American Chemical and Manufac- 
turing Corporation 
Armour Glue Works 
Armour Soap Works 
Babcock Testing Laboratory 
Corn Products Refining Company 
Cudahy Packing Co., The 
Dunham, H. V. 
Electrolabs Company, The 
Fort Worth Laboratories 
Globe Soap Company, The 
Industrial Testing Laboratories 
Kalmus, Comstock & Wcscott, Inc. 
Kidde, Walter, & Company 
Larkin Co. 



, INDUSTRIAL RESEARCH LABORATORIES 



107 



Laucks, I. F., Inc. 

Lehn & Fink, Inc. 

Lockhart Laboratories 

Mcllhiney, Parker C 

Miner Laboratories^ The 

Mojonnier Bros. Co. 

Musher and Company, Incorpo- 
rated 

National Lead Company 

Ohio Grease Co., The 

Palmolive Company, The 

Peet Bros. Mfg. Co. 

Procter & Gamble Co., The 

Pure Oil Company, Moore Oil and 
Refining Company Division 

Riverbank Laboratories 

Schaeffer Brothers & Powell 
Manufacturing Company 

Schwarz Laboratories 

Seydel Manufacturing Company 

Skinner, Sherman & Esselen, In- 
corporated 

Souther, Henry, Engineering Co., 
The 

Southern Cotton Oil Company, 
The 

Swift & Company 

Wells, Raymond 

Wheeler & WoodruflF 

Wiley & Company, Inc. 

Filtration 

Celite Products Company 
DeLaval Separator Co., The 
Dorr Company, The 
International Filter Co. 
Oliver Continuous Filter Co. 
Sperry, D. R., & Co. 

Fire prevention (extinguishers, 
sprinklers) 

Factory Mutual Laboratories 
MacAndrews & Forbes Company 
Underwriters' Laboratories 

Food8*(aIimentary pastes, bakery, 
baking powder, biscuit, butter, 
candy, canning and preserving, 
cold storage, flavoring extracts, 
flour, gelatine, meat and meat 



products, milk, oils, preserva- 
tives, wheat, yeast, etc.) 

American Can Company 
American Hominy Company 
American Institute of Baking 
Banks & Craig 
Brach, E. J., and Sons 
Bridgeman-Russell Company 
Brown Company 

California Fruit Growers Ex- 
change 
Carus Chemical Company 
Cleveland Testing Laboratory Co., 

The 
Com Products Refining Company 
Cudahy Packing Co., The 
Dunham, H. V. 
Emerson Laboratory 
Forth Worth Laboratories 
Frees, H. K, Co., The 
Gibbs Preserving Company 
Glass Container Association of 

America 
Hochstadter Laboratories 
Hooker Electrochemical Company 
Howard Wheat and Flour Test- 
ing Laboratory, The 
Industrial Research Laboratories 
Industrial Testing Laboratories 
Jaques Manufacturing Company 
Lehn & Fink, Inc. 
Long & Co., Inc. 
McLaughlin Gormley King Co. 
Merrell-Soule Laboratory 
Miner Laboratories, The 
Mojonnier Bros. Co. 
Morris & Company 
Musher and Company, Incorpo- 
rated 
National Biscuit Company 
National Canners Association 
National Cereal Products Labora- 
tories 
National Laboratories, The 
Nestle's Food Company, Incorpo- 
rated 
Newark Industrial Laboratories 
New England Confectionery Com- 
pany 

Nowak Chemical Laboratories 



10b 



INDUSTRIAL RESEARCH LABORATORIES 



Pease Laboratories 

Penick & Ford, Ltd., Incorporated 

Pittsburgh Testing Laboratory 

Procter & Gamble Co., The 

Redlands Fruit Products G)m- 
pany 

Rumford Chemical Works 

Schwarz Laboratories 

Sears, Roebuck and Co. 

Seydel Manufacturing Company 

Skinner, Sherman & Esselen, In- 
corporated 

Southern Cotton Oil Company, 
The 

Sprague, Warner ft Company 

Swift & Company 

Takamine Laboratory, Inc. 

Telling-Belle Vernon Company, 
The 

United Chemical and Organic 
Products Co. 

U. S. Food Products Corp. 

United SUtes Glue Co. 

Wahl-Henius Institute, Incorpo- 
rated 

Wallace ft Tieman Co., Inc. 

Washburn-Crosby Co. 

Wheeler ft WoodruflF 

Whitten, J. O., Company, The 

Wilckes, Martin, Wilckes Com- 
pany 

Wilson ft Co. 



Foundry equipment, 
and methods (casting, die cast- 
ing, moulding) 

American Brass Company, The 

Crane Co. 

Doehler Die-Casting Co. 

General Motors Research Corpo- 
ration 

Gurley, W. ft L. E. 

Lunkenheimer Co., The 

Niles Tool Works Company, The 

Pettee, Charles L. W., Labora- 
tories of 

Rhode Island Malleable Iron 
Works 

Stockham Pipe ft Fittings Co. 



Union Carbide and Carbon Re- 
search Laboratories, Inc. 

United States Bronxe Powder 
Works, Inc. 

Fuels (alcohol, charcoal, coal, 
coke, gasoline, kerosene, oil, 
peat See also gas, petroleum 
and wood) 

American Can Company 

American Radiator Company 

Anaconda Copper Mining Co. 

Andrews, A. B. 

Atlantic Refintng Company, The 

Babcock ft Wikox Co., The 

Barrett Company, The 

Bridgeman-Russell Company 
. Chemical Service Laboratories, 
Inc., The 

Commercial Testing and Engineer- 
ing Co. 

Consolidated Gas Company of 
New Yoric 

Dearborn Chemical Company 

Detroit Testing Laboratory, The 

Dodge Brothers 

Doherty Research Company, Em- 
pire Division 

Electrical Testing Laboratories 

Emerson Laboratory 

Federal Products Company, The 

General Motors Research Corpo- 
ration 

Gulf Pipe Line Company 

Hyco Fuel Products Corporation 

Industrial Chemical Institute of 
Milwaukee 

Industrial Testing Laboratories 

Interocean Oil Company, The 

James Ore Concentrator Co. 

Koppers Company, The 

Laucks, I. F., Inc. 

Lewis, F. J., Manufacturing Co. 

Little, Arthur D., Inc. 

Lockhart Laboratories 

Martinez Refinery, Shell Co. of 
California 

Meigs, Bassett ft Slaughter, Inc. 

Milwaukee Coke ft Gas Company, 
The 

Ohio Fuel Supply Company, The 



INDUSTRIAL RESEARCH LABORATORIES 



109 



Porter, Horace C. 

Providence Gas G>mpany, Incor- 
porated 

Quinn, T. H., ft G>nipany 

Rhode Island Malleable Iron 
Works 

Rodman Chemical Company 

Schwarz Laboratories 

Sears, Roebuck and Co. 

Souther, Henry, Engineering Co., 
The 

Standard Oil Company (New 
Jcrs^) 

U. S. Industrial Alcohol Company 

United States Smelting, Refining 
ft Mining Company 

Wayne Oil Tank and Pump Co. 

Western Gas Construction Com- 
pany, The 

Western Research Corporation, 
Incorporated 

Wheeler ft Woodruff 

Wiley ft Company, Inc. 

Fuel utilization (boilers, furnaces, 
gas - producers, radiators, 
stokers) 

American Blower Company 

American Radiator Company 

Brooklyn Union Gas Company, 
The 

Celite Products Company 

Champion Porcelain Company 

Cochrane, H. S. B. W., Corpora- 
tion 

Commercial Testing and Engineer- 
ing Co. 

Consolidated Gas Company of 
New York 

Consolidated Gas, Electric Light 
and Power Company of Balti- 
more 

Doherty Research Company, Em- 
pire Division 

Hunt, Robert W., and Co. 

Kidde, Walter, & Company 

Koppers Company, The 

Porter, Horace C. 

Rhode Island Malleable Iron 
Works 



Western Gas Construction Com- 
pany, The 
Wheeler ft Woodruff 

Gas, fuel and illuminating^ in- 
cluding mantles (acetylene, 
hydrogen) 

Brooklyn Union Gas Company, 
The 

Chemical Service Laboratories, 
Inc. 

Consolidated (jas Company of 
New York 

Consolidated Gsls, Electric Light 
and Power Company of Balti- 
more 

Cosden ft (^mpany 

Detroit Edison Company, The 

Gulf Pipe Line Company 

Harrison Mfg. Co., The 

Koppers Company, The 

Little, Arthur D., Inc. 

Milwaukee Coke ft Gsls Company, 
The 

Ohio Fuel Supply Company, The 

Porter, Horace C. 

Providence Gas Company, Incor- 
porated 

Standard Oil Company (New 
Jersey) 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

United Gas Improvement Co., The 

Welsbach Company 

Western Gas Construction Com- 
pany, The 

Wheeler ft Woodruff 

Gases, except fuel and illumina- 
ting, including generating ap- 
paratus (argon, chlorine, 
helium, neon, nitrogen, oxygen, 
poisonous gases) 

Burdctt Manufacturing Company 
Electrolabs Company, The 
Florida Wood Products Co. 
Great Western Electro-CHiemical 
Company 

Hooker Electrochemical Company 
Lennox Chemical Co., The 



110 



INDUSTRIAL RESEARCH LABORATORIES 



Mathieson Alkali Works, Inc., The 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

Wallace & Tiernan Co., Inc. 

Western Gas Construction Com- 
pany, The 

Hair, curled, etc. 

Armour Curled Hair Works 
Cudahy Packing Co., The 
Pfister & Vogel Leather Co. 

Heat (calorimetry, pyrometry, 
thermal physics, thermometry) 

Celite Products Company 
Commonwealth Edison Company 
General Motors Research Corpo- 
ration 
Koppers Company, The 
Leeds & Northrup Company 
Munn, W. Faitoute 
Pyrolectric Instrument Company 
Rhode Island Malleable Iron 

Works 
Swenson Evaporator Company 
Union Carbide and Carbon Re- 
search Laboratories, Inc. 
Wahl-Henius Institute, Incorpo- 
rated 

Heating 

American Blower Company 
American Radiator Company 
Cochrane, H. S. B. W., Corpora- 
tion 
Detroit Edison Company, The 
Hoskins Manufacturing Company 

Hydraulics (waterworks, water 
power) 

Cochrane, H. S. B. W., Corpora- 
tion 

Cramp, William, & Sons Ship & 
Engine Building Co., The 

Illumination, electric, gas and 
other 

Brooklyn Union Gas Company, 
The 



Commonwealth Edison Company 

Consolidated Gas Company of 
New York 

Consolidated Gas, Electric Light 
and Power Company of Balti- 
more 

Cooper Hewitt Electric Company 

Coming Glass Works 

Harrison Mfg. Co., The 

National Lamp Works of General 
Electric Company 

Ohio Fuel Supply Company, The 

Providence Gas Company, Incor- 
porated 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

United Gas Improvement Co., The 

Welsbach Company 

Westinghouse Electric & Manu- 
facturing Company 

Westinghouse Lamp Co. 

Insulation, electrical and thermal 
(cable, cordage, non-conduc- 
tors, insulated wire) 

Allen-Bradley Co. 

Belden Manufacturing Company 

Boonton Rubber Manufacturing 

Company 
Carborundum Company, The 
Celite Products Company 
Champion Ignition Company 
Condensite Company of America 
Electrical Testing Laboratories 
General Bakelite Company 
Habirshaw Electric Cable Com- 
pany, Inc. 
Kellogg Switchboard and Supply 

Co. 
Kilbourne ft Clark Manufacturing 

Company 
Redmanol Chemical Products Co. 
Sangamo Electric Company 
Standard Underground Cable 

Company 
Vacuum Oil Company, Incorpo- 
rated 



INDUSTRIAL RESEARCH LABORATORIES 



111 



Internal combustion motors (Die- 
sel engines, gasoline engines, 
motors, oil engines) 

Abbott, William G., Jr. 

Bethlehem Shipbuilding Corpora- 
tion, Ltd. 

General Motors Research Corpo- 
ration 

Ingersoll-Rand Company 

Standard Oil Company (New 
Jersey) 

Studebaker Corporation, The 

Iron and steel (cast iron, ferrous 
alloys, pipe, wrought iron) 

American Chemical Paint Com- 
pany 

American Rolling Mill Co., The 

American Sheet and Tin Plate 
Company 

Barber-Colman Company 

Borrowman, George 

Buffalo Foundry and Machine Co. 

Byers, A. M., Company 

Carnegie Steel Company 

Chase Metal Works 

Cleveland Testing Laboratory Co., 
The 

Crane Co. 

Crompton & Knowlcs Loom Works 

Crucible Steel Company of Amer- 
ica 

Diamond Chain & Manufacturing 
Company 

Dodge Brothers 

Duriron Company, Inc., The 

Eastern Malleable Iron Company 

Fahy, Frank P. 

Fansteel Products Company, Inc. 

General Motors Research Corpo- 
ration 

Gillette Safety Razor Co. 

Houghton, £. F., & Co. 

Hunt, Robert W., and Co. 

Industrial Works 

Inland Steel Company 

Kokomo Steel and Wire Co. 

Ludlum Steel Company 

Lunkenheimer Co., The 

Maynard, T. Poole 



McNab & Harlin Manufacturing 

Co. 
Mesabi Iron Company 
Midvale Steel and Ordnance Com- 
pany 
Minneapolis Steel and Machinery 

Ca 
National Malleable Castings Com- 
pany, The 
National Tube Company 
Nilcs Tool Works Company, The 
Peerless Drawn Steel Company, 

The 
Pettee, Charles L. W., Labora- 
tories of 
Pierce-Arrow Motor Car Com- 
pany, The 
Rhode Island Malleable Iron 

Works 
Rodman Chemical Company 
Sangamo Electric Company 
Stockham Pipe & Fittings Co. 
Tacony Steel Company 
Titanium Alloy Manufacturing Co. 
Union Carbide and Carbon Re- 
search Laboratories, Inc. 
United Alloy Steel Corporation 
United States Smelting, Refining 

& Mining Company 
Vanadium- Alloys Steel Co., The 
Vanadium Corporation of America 
Waltham Watch Company 
Western Gas Construction Com- 
pany, The 

Leather and leather goods (boots, 
shoes, including machinery, 
leather substitutes, tanning) 

Atlas Powder Co. 

Carus Chemical Company 

Dennis, Martin, Company, The 

Durfee, Winthrop C. 

Gallun, A. F., & Sons Co. 

Houghton, E. F., & Co. 

International Shoe Co. 

Kidde, Walter, & Company 

Kullman, Salz & Co. 

New York Quebracho Extract 

Company, Incorporated 
Pantasote Leather Company, The 



112 



INDUSTRIAL RESEARCH LABORATORIES 



Pfister & Vogel Leather Co. 

United Shoe Machinery Corpora- 
tion 

Vactram Oil Company, Incorpo- 
rated 

Light (optical instruments, optics. 
See also illumination) 

American Optical Company 
Bausch & Lomb Optical Co. 
Case Research Laboratory 
Cooper Hewitt Electric Company 
Coming Glass Works 
Eastman Kodak Company 
Gurley, W. & L. E. 
Keuffel & Esser Co. 
National Lamp Works of General 

Electric Company 
Spencer Lens Company 

Liquors, fermented and distilled 
(alcohol, beer, wirie) 

Frees, H. R, Co., The 
Industrial Chemical Institute of 

Milwaukee 
Industrial Testing Laboratories 
National Laboratories, The 
Nowak Chemical Laboratories 
Wahl-Henius Institute, Incorpo- 
rated 
Wiley & Company, Inc. 

Lubricants (carbon, graphite, oil, 
petroleum) 

Acheson Graphite Company 

Chase Metal Works 

Columbia Graphophone Manufac- 
turing Company 

Commercial Testing and Engineer- 
ing Co. 

Dearborn Chemical Company 

Dodge Brothers 

Doherty Research Company, Em- 
pire Division 

Gray Industrial Laboratories, The 

Industrial Testing Laboratories 

Interocean Oil Company, The 

Laucks, I. F., Inc. 

Lf ickhart . Laboratories 



Martinez Refinery, Shell Co. of 
California 

Maynard, T. Poole 

Minneapolis Steel and Machinery 
Co. 

Ohio Grease Co., The 

Pittsburgh Testing Laboratory 

Pure Oil Company, Moore Oil and 
Refining Company Division 

Schwarz Laboratories 

S. K. F. Industries, Inc. 

Speer Carbon Company 

Standard Oil Company (New 
Jersey) 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

Vacuum Oil Company, Incorpo- 
rated 

Ventura Refining Company 

Wayne Oil Tank and Pump Ca 

Weld and Liddell 

Wells, Raymond 

Western Gas Construction Com- 
pany, The 

Western Research Corporation, 
Incorporated 

Wheeler & Woodruff 

Wiley & Company, Inc. 

Machine tools and hardware (cut- 
lery, drill-presses, lathes, 
planers, shapers) 

Barber-Colman Company 
Brown & Sharpe Mfg. Co. 
Niles Tool Works Company, The 
Rochester Button Company 
Stockham Pipe & Fittings Co. 
United Shoe Machinery Corpora- 
tion 
Winchester Repeating Arms Co. 

Magnetism 

Electrical Testing Laboratories 
Kilboume & Clark Manufacturing 

Company 
Leeds & Northrup Company 

Marine engineering (ships) 

Cramp, William, & Sons Ship ft 
Engine Building Co., The 



INDUSTRIAL RESEARCH LABORATORIES 



113 



Matches 

Diamond Match Co., The 

Mechanics, general (bearings, 
bail, roller, etc.). 

Minneapolis Steel and Machinery 

Co. 
National Cash Register Company, 

The 
S. K. F. Industries, Inc. 

Metal manufactures, miscellan- 
eous (fittings, pipes, valves) 

Byers, A. M., Company 

Crane Co. 

Grasselii Chemical Company 

Lmikenheimer Co., The 

McNab & Harlin Manufacturing 
Ca 

National Tube Company 

Scovill Manufacturing Company 

Stockham Pipe & Fittings Co. 

Western Gas Construction Com- 
pany, The 

Winchester Repeating Arms Co. 

Metallurgy and metallography, in- 
cluding equipment 

American Brass Company, The 
American Optical Company 
American Sheet and Tin Plate 

Company 
Anaconda Copper Mining Co. 
Babcock & Wilcox Co., The 
Bennetts' Chemical Laboratory 
Borrowman, George 
Bridgeport Brass Company 
Buffalo Foundry and Machine Co. 
Byers, A. M., Company 
Calumet ft Hecla Mining Com- 
pany 
Carnegie Steel Company 
Chase Metal Works 
Qeveland Testing Laboratory Co., 

The 
Crane Co. 

Crompton ft Knowles Loom Works 
Detroit Testing Laboratory, The 
Dodge Brothers 



Dorr Company, The 

Duriron Cotiapany, Inc., The 

Eastern Malleable Iron Company 

Eustis, F. A. 

Fansteel Products Company, The 

FitzGerald Laboratories, Inc., The 

General Electric Company 

General Engineering Company, In- 
corporated, The 

General Motors Research Corpo- 
ration 

Gillette Safety Razor Co. 

Hirsch Laboratories, Inc., The 

Hoskins Manufacturing -Company 

Hunt, Robert W., and Co. 

Industrial Works 

International Nickel Company, 
The 

James Ore Concentrator Co. 

Kalmus, Comstock ft Wescott, Inc. 

Kokomo Steel and Wire Co. 

Lumen Bearing Company 

Lunkenheimer Co., The 

McNab ft Harlin Manufacturing 
Co. 

Metals & Chemicals Extraction 
Corporation 

Midvale Steel and Ordnance Com- 
pany 

Minneapolis Steel and Machinery 
Ca 

National Cash Register Company, 
The 

National Lamp Works of General 
Electric Company 

National Lead Company 

National Malleable Castings Com- 
pany, The 

Niles Tool Works Company, The 

Oliver Continuous Filter Co. 

Peerless Drawn Steel Company, 
The 

Pierce-Arrow Motor Car Com- 
pany, The 

Raritan Copper Works 

Research Corporation 

Rhode Island Malleable Iron 
Works 

Rodman Chemical Company 

Scovill Manufacturing Company 



114 



INDUSTRIAL RESEARCH LABORATORIES 



Sears, Roebuck and Co. 

S. K. F. Industries, Inc. 

Souther, Henry, Engineering Co., 
The 

Stewart - Warner Speedometer 
Corporation 

Studebaker Corporation, The 

Titanium Alloy Manufacturing Co. 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

United Alloy Steel Corporation 

United States Metals Refining Co. 

United Sutes Smelting, Refining 
& Mining Company 

Vanadium Corporation of Amer- 
ica 

Wadsworth Watch Case Co., In- 
corporated, The 

Wahham Watch Company 

Wedge Mechanical Furnace Com- 
pany 

Westinghouse Electric & Manu- 
facturing Company 

Wheeler & Woodruff 

Military and naval equipment 
(ammunition, armor, ordnance, 
small arms, torpedoes) 

Abbott, William G., Jr. 

Remington Arms, Union Metallic 
Cartridge Company 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

Winchester Repeating Arms Co. 

Mining, general (testing drills, 
ropes, tools ; ore dressing) 

Deister Concentrator Company, 

The 
Doherty Research Company, Em- 
pire Division 
Dorr Company, The 
IngersoU-Rand Company 
James Ore Concentrator Co. 
Maynard, T. Poole 
National Lead Company 
Oliver Continuous Filter Co. 
United States Smelting, Refining 
& Mining Company 



Non-ferrous metals (aluminum, 
bearing metals, brass, bronze, 
copper, gold, lead, nickel, plati- 
num, silver, tin, titanium, zinc) 

Aluminum Company of America 

American Brass Company, The 

American Can Company 

American Sheet and Tin Plate 
Company 

Anaconda Copper Mining Co. 

Baker & Ca, Inc. 

Bethlehem Shipbuilding Corpora- 
tion, Ltd. 

Bridgeport Brass Company 

Calumet ft Hecla Mining Company 

Chase Metal Works 

Cramp, William, & Sons Ship ft 
Engine Building Co., The 

Crane Co. 

Crompton & Knowles Loom Works 

Dodge Brothers 

Doehler Die-Casting Co. 

Eagle-Picher Lead Company, The 

Fansteel Products Company, Inc. 

General Motors Research Corpo- 
ration 

Glidden Company, The 

Grasselli Chemical Company 

Grosvenor, Wm. M. 

Gurley, W. ft L. E. 

Hochstadter Laboratories 

Industrial Works 

International Nickel Company, The 

International Silver Company 

Lumen Bearing Company 

Lunkenheimer Co., The 

McNab ft Harlin Manufacturing 
Co. 

Metals ft Chemicals Extraction 
Corporation 

Mineral Refining ft Chemical Cor- 
poration 

National Canners Association 

National Lamp Works of General 
Electric Company 

National Lead Company 

New Jersey Zinc Company 

Niles Tool Works Company, The 

Pettee, Charles L. W., Labora- 
tories of 



INDUSTRIAL RESEARCH LABORATORIES 



115 



Radium Company of Colorado, 
Inc., The 

Radium Limited, U. S. A. 

Raritan Copper Works 

Remington Arms, Union Metallic 
Cartridge Company 

Roessler & Hasslacher Chemical 
Company, The 

Scovill Manufacturing Company 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

United States Bronze Powder 
Works, Inc. 

United States Metals Refining Co. 

United States Smelting, Refining 
& Mining Company 

Vanadium Corporation of Amer- 
ica 

Wadsworth Watch Case Co., In- 
corporated, The 

Waltham Watch Company 

Weld and Liddell 

0£Ece equipment (adding ma- 
chines, cash registers) 

Abbott, William G., Jr. 
National Cash Register Company, 
The 



;, oils and varnishes (dryers, 
enamels, lacquers, pigments, 
putty, resins, rust-proofing) 

Abbott, William G.. Jr. 

Acme White Lead & Color Works 

American Chemical and Manufac- 
turing Corporation 

American Chemical Paint Com- 
pany 

Andrews, A. B. 

Ansbacher, A. B., & Company 

Atlas Powder Co. 

Ault & Wiborg Company, The 

Babcock Testing Laboratory 

Berry Brothers, Inc. 

Borrowman, George 

Boyer Chemical Laboratory Com- 
pany 

Buchanan, C. G., Chemical Com- 
pany 

Cabot, Samuel, Inc. 

Cams Chemical Company 



Chase Metal Works 

Childs, Charles M., & Co., Inc. 

Chemical Products Company 

Condensite Company of America 

Davis Chemical Products, Inc. 

Dodge Brothers 

Drackett, P. W., & Sons Co., The 

du Pont, £. I., de Nemours & 
Company 

Eagle-Picher Lead Company, The 

Glidden Company, The 

Grosvenor, Wm. M. 

Hunt, Robert W., and Co. 

Imperial Belting Company 

Industrial Chemical Institute of 
Milwaukee 

Industrial Testing Laboratories 
' Krebs Pigment and Chemical Co. 

Lakeview Laboratories 

Little, Arthur D., Inc. 

Lockhart Laboratories 

Mcllhiney, Parker C. 

Mineral Refining & Chemical Cor- 
poration 

National Laboratories, The 

National Lead Company 

Newport Company, The 

Perolin Company of America, The 

Pfister & Vogel Leather Co. 

Pittsburgh Plate Glass Co. 

Pyro-Non Paint Co., Inc. 

Redmanol Chemical Products Co. 

Richardson Company, The 

Rubber Trade Laboratory, The 

Sangamo Electric Company 

Sears, Roebuck and Co. 

Skinner, Sherman & Esselen, In- 
corporated 

Titanium Pigment Co., Inc. 

Toch Brothers 

Ultro Chemical Corporation 

United States Bronze Powder 
Works, Inc. 

Wayne Oil Tank and Pump Co. 

Wells, Raymond 

Wheeler & Woodruff 

Zobel, Ernst, Company, Inc. 

Petroleum and its products (see 
also lubricants) 

Atlantic Refining Company, The 



116 



INDUSTRIAL RESEARCH LABORATORIES 



Babcock Testing Laboratory 

Barber Asphalt Paving G>mpany, 
The 

Charlotte Chemical Laboratories, 
Inc. 

Cosden & Company 

Doherty Research Company, Em- 
pire Division 

Dunham, H. V. 

Gray Industrial Laboratories 

Gulf Pipe Line Company 

Institute of Industrial Research, 
The 

Interocean Oil Company, The 

Little, Arthur D., Inc. 

Lockhart Laboratories 

Martinez Refinery, Shell Co. of 
California 

Ohio Fuel Supply Company, The 

Richardson Company, The 

Schaeffer Brothers ft Powell 
Manufacturing Company 

Standard Oil Company (New 
Jersey) 

Standard Oil Company of Indiana 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

Vacuum Oil Company, Incorpo- 
rated 

Ventura Refining Company 

Wayne Oil Tank and Pump Co. 

Weld and Liddell 

Western Gas Construction Com- 
pany, The 

Western Research Corporation, In- 
corporated 

Wheeler ft Woodruff 

2^bel, Ernst, Company, Inc. 

Phonographs and graphophones 

Columbia Graphophone Manufac- 
turing Company 
Edison, Thomas A., Laboratory 

Photography (c a m e r a a, de- 
velopers, films, moving-pic- 
ture equipment, plates) 

Ansco Company 

Chemical Economy Company 

Coming Glass Works 



Eastman Kodak Company 

Grosvenor, Wm. M. 

Heinrich Laboratories of Applied 

Chemistry 
Hirsch Laboratories, Inc., The 
Kalmus, Comstock & Wescott, Inc. 
Munn, W. Faitoute 
National Lead Company 
United States Glue Co. 
Zinsser ft Co. 

Plastics (bakelite, condensite, red- 
manol ; casting and moulding of 
plastics) 

Abbott, WilUam G., Jr. 

Boonton Rubber Manufacturing 
Company 

Champion Ignition Company 

Columbia Graphophone Manufac- 
turing Company 

Condensite Company of America 

du Pont, E. L, de Nemours ft 
Company 

General Bakelite Company 

Heap, William, ft Sons 

Meigs, Bassett ft Slaughter, Inc. 

Redmanol Chemical Products Co. 

Rubber Trade Laboratory, The 

Properties of engineerhig ma- 
terials 

American Brass Company, The 

Borrowman, George 

Carborundtun Company, The 

Chicago Mill and Lumber Com- 
pany 

Columbia Graphophone Manufac- 
ing Company 

Electrical Testing Laboratories 

General Electric Company 

Hunt, Robert W., and Co. 

Industrial Works 

Institute of Industrial Research, 
The 

Kokomo Steel and Wire Co. 

Maynard, T. Poole 

National Association of Corru- 
gated and Fibre Box Manufac- 
turers, The 



INDUSTRIAL RESEARCH LABORATORIES 



117 



Pennsylvania Railroad Company, 
The 

Pierce-Arrow Motor Car Com- 
pany, The 

Scovill Manufacturing Company 

Skinner, Sherman & Esselen, In- 
corporated 

Stewart- Warner Speedometer Cor- 
poration 

Swenson Evaporator Company 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

United Shoe Machinery Corpora- 
tion 

Public utilities 

Detroit Edison Company, The 
Doherty Research Company, Em- 
pire Division 
Stone & Webster, Incorporated 

Pulp and paper (cellulose) 

American Writing Paper Co. 

Andrews, A. B. 

Atlas Powder Co. 

Babcock Testing Laboratory 

Beaver Board Companies, The 

Brown Company 

Carborundum Company, The 

Chemical Economy Company 

Chemical Products Company 

Chicago Mill and Lumber Com- 
pany 

Crane ft Co. 

Cumberland Mills 

Davis Chemical Products, Inc. 

Dill & Collins Co. 

du Pont, E. I., de Nemours & 
Company 

Eastern Manufacturing Company 

Eastman Kodak Company 

Emerson Laboratory 

Glysyn Corporation, The 

Grosvenor, Wm. M. 

Hammerslcy M'f'g Co., The 

Heap, William, & Sons 

Hooker Electrochemical Company 

Industrial Testing Laboratories 

Little, Arthur D., Inc. 
. MacAndrews ft Forbes Company 



Meigs, Bassett ft Slaughter, Inc. 

Metals & Chemicals Extraction 
Corporation 

Munn, W. Faitoute 

National Association of Corru- 
gated and Fibre Box Manufac- 
turers, The 

National Laboratories, The 

Oliver Continuous Filter Co. 

Package Paper and Supply Cor- 
poration 

Richardson Company, The 

Skinner, Sherman ft Esselen, In- 
corporated 

Strathmore Paper Company 

Van Schaack Brothers Chemical 
Works, Inc. 

Wallace, Joseph H., ft Co. 

Weston, Byron, Co. 

Wiley & Q>mpany, Inc. 

Railroad equipment (cars, loco- 
motives, signals, etc.) 

Baldwin Locomotive Works, The 
Hunt. Robert W., and Ca 
Industrial Works 
Niles Tool Works Company, The 
Pennsylvania Railroad Company, 
The 

Union Switch ft Signal Company 

Razors 

Gillette Safety Razor Ca 

Refrigeration (artificial ice) 

American Radiator Company 
Ansul Chemical Company 
General Motors Research Corpo- 
ration 
Industrial Research Corporation 
Industrial Testing Laboratories 
International Filter Ca 

Rubber and rubber goods, includ- 
ing other natural gums (gutta- 
percha) 

Abbott, William G., Jr. 
Belden Manufacturing Company 
Boonton Rubber Manufacturing 
Company 



118 



INDUSTRIAL RESEARCH LABORATORIES 



Brunswick - Bailee - Collender G>., 

The 
Carborundum Company, The 
Columbia Graphophone Manufac- 
turing Company 
Dodge Brothers 
Falls Rubber Company, The 
Firestone Tire & Rubber Company 
General Bakelite Company 
General Tire & Rubber Co. 
Goodrich, B. F., Company, The 
Goodyear Tire & Rubber Com- 
pany, The 
Hood Rubber Company 
Manhattan Rubber Mfg. Co., The 
Miller Rubber Co., The 
Portage Rubber Co., The 
Redmanol Chemical Products Co. 
Rubber Trade Laboratory, The 

Soils and fertilizers (nitrates, 
phosphates, potash) 

American Agricultural Chemical 

Company, The 
American Cyanamid Company 
American Trona Corporation 
Anaconda Copper Mining Co. 
Armour Fertilizer Works 
Cudahy Packing Co., The 
Detroit Testing Laboratory, The 
Grasselli Chemical Company 
Maynard, T. Poole 
Meigs, Bassett & Slaughter, Inc. 
Metals & Chemicals Extraction 

Corporation 
Morris & Company 
Royster, F. S., Guano Company 
Sears, Roebuck and Co. 
Swift & Company 
United Chemical and Organic 

Products Co. 
United States Glue Co. 
Utah-Idaho Sugar Company 
Wiley & Company, Inc. 

Sound (acoustics) 

Columbia Graphophone Manufac- 
turing Company 
Hayes, Hammond V. 
Riverbank Laboratories 



Sabine, Wallace Clement, Labora- 
tory 

Steam power (boilers, econ- 
omizers, engines, turbines. 
See also internal combustion 
motors) 

American Radiator Company 
Babcock & Wilcox Co., The 
Bethlehem Shipbuilding Corpora- 
tion, Ltd. 
Cochrane, H. S. B. W., Corpora- 
tion 
Commercial Testing and Engineer- 
ing Co. 
Detroit Edison Company, The 
Ingersoll-Rand Company 
Lunkenheimer Co., The 
Minneapolis Steel and Machinery 
Ca 

Subatomic phenomena and radio- 
activity 

Radium Company of Colorado, 

Inc., The 
Radium Limited, U. S. A. 
Riverbank Laboratories 
Welsbach Company 

Sugar (sorghums, syrups) 

American Beet Sugar Company 
American Diamalt Company 
American Sugar Refining Com- 
pany, The 
Dehls & Stein 
Digestive Ferments Co. 
Feculose Co. of America 
Great Western Sugar Company, 

The 
Industrial Chemical Institute of 

Milwaukee 
Industrial Testing Laboratories 
New York Sugar Trade Labora- 
tory, Inc., The 
Nulomoline Company, The 
Oliver Continuous Filter Co. 
Penick & Ford, Ltd., Incorporated 
Schwarz Laboratories 
Spreckels Sugar Company 
Swenson Evaporator Company 



INDUSTRIAL RESEARCH LABORATORIES 



119 



U. S. Food Products Corp. • 
Utah-Idaho Sugar Company 
Western Sugar Refinery 

Surgical, dental and hospital 
equipment and supplies 

Caulk, L. D., Company, The 
Johnson & Johnson 
Lakeview Laboratories 
Ransom & Randolph Co., The 
Union Carbide and Carbon Re- 
search Laboratories, Inc. 

Tar and its products 

Barrett Company, The 

Glysyn Corporation, The 

Koppers Company, The 

Laucks, I. F., Inc. 

Lyster Chemical Company, Inc. 

Providence Gas Company, Incor- 
porated 

Quinn, T. H., & Company 

Rubber Trade Laboratory, The 

Union Carbide and Carbon Re- 
search Laboratories, Inc. 

White Tar Company of New Jer- 
sey, Inc., The 

Zobel, Ernst, Company, Inc. 

Textiles, including machinery 
(buttons, clothing, cotton and 
its products, linen, wool ; water- 
proofing) 

Abbott, William G., Jr. 

Amoskeag Manufacturing Com- 
pany 

Arlington Mills 

Art in Buttons 

Barber-Colman Company 

Chemical Products Company 

Crompton & Knowles Loom Works 

Durfee, Winthrop C. 

Eastern Finishing Works, Inc. 

Eavenson & Levering Co. 

Emerson Laboratory 

Glysyn Corporation, The 

Grosvenor, Wm, M. 

Imperial Belting Company 

Industrial Chemical Institute of 
Milwaukee 



Klearflax Linen Rug Company 

Little, Arthur D., Inc. 

Maynard, T. Poole 

Metakloth Co. 

Rochester Button Company 

Roessler & Hasslacher Chemical 

Company, The 
Rubber Trade Laboratory, The 
Sears, Roebuck and Co. 
U. S. Testing Co., Inc. 

Water, sewage and sanitation 

American Institute of Baking 
Babcock & Wilcox Co., The 
Banks & Craig 

Borromite Co. of America, The 
Borrowman, George 
Bridgeman-Russell Company 
Cams Chemical Company 
Cochrane, H. S. B. W., Corpora- 
tion 
Dearborn Chemical Company 
Detroit Testing Laboratory, The 
Dorr Company, The 
Emerson Laboratory 
Fort Worth Laboratories 
Great Western Electro-Chemical 

Company 
Hochstadter Laboratories 
Hooker Electrochemical Company 
Industrial Chemical Institute of 

Milwaukee 
Industrial Testing Laboratories 
International Filter Co. 
Kidde, Walter, & Company, Incor- 
porated 
Oliver Continuous Filter Co. 
Pease Laboratories 
Permutit Company, The 
Perolin Company of America, The 
Souther, Henry, Engineering Co., 

The 
Wallace & Tieman Co., Inc. 
Wells, Raymond 
Weston & Sampson 
Wheeler & Woodruff 
White Tar Company of New Jer- 
sey, Inc., The 



120 



INDUSTRIAL RESEARCH LABORATORIES 



Welding, autogenous, gas, elec- 
tric, forge 

Bethlehem Shipbuilding G>rpora- 

tion, Ltd. 
Davis-Boumonville Company 
Electrolabs G)mpany, The 
Hoskins Manufacturing G>mpany 
Union Carbide and Carbon Re- 
search Laboratories, Inc. 
Western Gas Construction Com- 
pany, The 



Wire 



Belden Manufacturing Company 
Hoskins Manufacturing Company 
Kokomo Steel and Wire Co. 
Scovill Manufacturing Company 



Wood products, other than cellu- 
lose and paper (see also con- 
tainers) 

Andrews, A. B. 
Babcock Testing Laboratory 
Chicago Mill and Lumber Com- 
pany 
Florida Wood Products Co. 
Hercules Powder Co. 
Lakeview Laboratories 
Nowak Chemical Laboratories 
Quinn, T. H., ft Company 
Rodman Chemical Company 
Wallace, Joseph H., & Co. 
Zobel, Ernst, Company, Inc. 



INDUSTRIAL RESEARCH LABORATORIES 121 

ADDRESS LIST OF DIRECTORS OF RESEARCH 

Abbott, W. a, Jr^ Wilton, N. R 

Abrams, Duff A., Structural Materials Research Laboratory, Lewis Institute, 1951 

W. Madison St, Chicago, 111. 
Adams, H. S^ The Naugatuck Chemical Company, Naugatuck, Conn. 
Adams, William H., Eastern Finishing Works, Inc., Kenyon, R. I. 
Adamsoo, G. P., General Chemical Company, 25 Broad St., New York, N. Y. 
Agnew, Theodore M., Physicians and Surgeons' Laboratory, 605 Paxton Blk., 

Omaha, Nebr. 
Alexander, Jerome, Uniform Adhesive Company, Incorporated, foot of 3SHh St., 

Brooklyn, N. Y. 
Allen, A. S., The Lennox Chemical Co., Euclid, Ohio. 

Amend, C G., Eimer & Amend, Third Ave 18th to 19th Sts., New York, N. Y. 
Amend, O. P., Eimer ft Amend, Third Ave., 18th to 19th Sts., New York, N. Y. 
Anderegg, G. A., Western Electric Company, Incorporated, 463 West St, New 

York, N. Y. 
Anderson, John F., E R. Squibb ft Sons, New Brunswick, N. J. 
Andrews, A. B., Lewiston, Me. 

Angelli Chester M., Vesta Battery Corporation, 2100 Indiana Ave., Chicago, 111. 
Anglemyer, Wilbur J., Kellogg Switchboard and Supply Co., Adams and Aberdeen 

Sts., Chicago, IlL 
Anthony, Olney P., Geo. H. Morrill Co., Norwood, Mass. 
Appelbaum, A. I., Thac Industrial Products Corp., 58 Middle Rose St., Trenton, 

N.J. 
Arms, E W., W. ft L. E Gurley, 514 Fulton St., Trpy, N. Y. 
Armstrong, P. A. E, Ludlum Steel Company, Watervliet, N. Y. 
Arnold, H. D., Western Electric Company, Incorporated, 463 West St., New York, 

N. Y. 
Aston, James, A. M. Byers Company, Pittsburgh, Pa. 

Atkinson, F. C, American Hominy Company, 1857 Gent Ave., Indianapolis, Ind. 
Austin, Frederick J., William R, Warner ft Company, Incorporated, 113 W. 18th 

St, New York, N. Y. 
Austin, H., Ernest Scott & Company, Fall River, Mass. 
Avstreih, L M., Avri Drug & Chemical Company, Inc., 421 Johnston Ave., Jersey 

Gty, N. J. 
Babcock, S. C, Babcock Testing Laboratory, 803 Ridge Road, Lackawanna, N. Y. 
Backhaus, A. A., U. S. Industrial Alcohol Company, South Baltimore, Md. 
Badger, W. L., Swenson Evaporator Company, Ann Arbor, Mich. 
Baekeland, L. H., General Bakelite Company, Perth Amboy, N. J. 
Bailey, G. C, National Aniline & Chemical Company, Incorporated, Marcus Hook, Pa. 
Bailey, Herbert S., The Southern Cotton Oil Company, Savannah, Ga. 
Baker, J. C, Wallace & Tiernan Co., Inc., Box 178, Newark, N. J. 
Balke, Qarence W., Fansteel Products Company, Inc., North Chicago, 111. 
Banks, H. P., I. F. Laucks, Inc., 99 Marion St., Seattle, Wash. 
Banks, Henry W., Banks ft Craig, 51 East 42nd St., New York, N. Y, 
Barad, D. N., A. B. Ansbacher ft Company, 310 N. 7th St, Brooklyn, N. Y. 
Barnard, Harry E, American Institute of Baking, 1135 FuUerton Ave., Chicago, 111. 
Bartholomew, F. J., Charlotte Chemical Laboratories, Inc, 606 Trust Building, 

Charlotte, N. C 



122 INDUSTRIAL RESEARCH LABORATORIES 

Barton, L. E., Titanium Alloy Manufacturing Co., Niagara Falls, N. Y., also Tita- 
nium Pigment Co., Inc., Niagara Falls, N. Y. 

Base, Daniel, Hynson, Westcott & Dunning, 16 E. Hamilton St., Baltimore, Md. 

Bassett, Harry P., Meigs, Bassett ft Slaughter, Inc., Bala, Pa. 

Bassett, William H., The American Brass Company, Waterbury, Conn. 

Baxter, Florus R., Vacuum Oil Company, Incorporated, Rochester, N. Y. 

Baxter, H. A., Tacony Steel Company, Philadelphia, Pa. 

Bean, W. R., Eastern Malleable Iron Company, Naugatuck, Conn. 

Beaver, A. B., The National Cash Register Company, Dayton, Ohio. 

Bebie, Jules, Monsanto Chemical Works, 1800 South 2nd St., St. Louis, Mo. 

Beck, Wesley J., The American Rolling Mill Co., Middletown, Ohio. 

Beckman, J. W., Beckman and Linden Engineering Corporation, Balboa Building, 
San Francisco, Calif. 

Beegle, F. M., The Glidden Company, Qeveland, Ohio. 

Bell, W. H., The Coleman ft Bell Company, Norwood, Ohio. 

Benedict, C. H., Calumet & Hecla Mining Company, Lake Linden, Mich. 

Benger, E. B., E. I. du Pont, de Nemours ft Company, Parlin, N. J. 

Bengis, Robert O., Heyden Chemical Company of America, Inc., Garfield, N. J. 

Bennetts, B. H., Bennetts' Chemical Laboratory, 1142 Market St., Tacoma, Wash. 

Berry, C. W., Laclede-Christy Clay Products Company, 4600 S. Kingshighway, St. 
Louis, Mo. 

Bierbauer, C. F., Hercules Powder Co., Kenvil, N. J. 

Bierbaum, C. H., Lumen Bearing Company, Buffalo, N. Y. 

Bigelow, W. D., National Canners Association, 1739 H St. N. W., Washington, D. C. 

Bitting, A. W., Glass Container Association of America, 3344 Michigan Ave., 
Chicago, 111. 

Black; C. A., The Cleveland Testing Laboratory Co., 511 Superior Building, Qeve- 
land, Ohio. 

Black, Robert S., Special Chemicals Company, Highland Park, 111. 

Blanc, Charles, Cosmos Chemical Co., Inc., 709 Berckman St., Plainfield, N. J. 

Bloede, Victor G., Victor G. Bloede Co., Station D, Baltimore, Md. 

Boeck, P. A., Celite Products Company, Lompoc, Calif. 

Bolton, J. W., The Niles Tool Works Company, 545 North Third St, Hamilton, 
Ohia 

Bond, William G., Bond Manufacturing Corporation, Monroe and Fifth Sts., Wil- 
mington, Del. 

Bonnett, F., Jr., Atlas Powder Co., Landing, N. J. 

Booth, H. T., Curtiss Aeroplane ft Motor Corporation, Garden City, L. I., N. Y. 

Borror, W. A., Pure Oil Company, Belle, W. Va. 

Borrowman, George, 130 N. Wells St., Chicago, 111. 

Bovard, W. M., Package Paper and Supply Corporation, 150 Birnie Ave., Spring- 
field, Mass. 

Bowman, Jay, United Chemical and Organic Products Co., W. Hammond, 111. 

Boyer, A. D., Boyer Chemical Laboratory Company, 940 N. Clark St., Chicago, 111. 

Bradley, Lynde, Allen-Bradley Co., 286 Greenfield Ave., Milwaukee, Wis. 

Brady, Edward J., The United Gas Improvement Co., 3101 Passyunk Ave., Phila- 
delphia, Pa. 

Braude, Felix, Palatine Aniline and Chemical Corporation, 81 N. Water St, Pough- 
keepsie, N. Y. 

Brenner, R. F., H. C. Fry Glass Company, Rochetser, Pa. 

Brewer, J. Ed., The Chemical Service Laboratories, Inc., W. Conshohocken, Pa. 



INDUSTRIAL RESEARCH LABORATORIES 123 

Breyer, F. G^ The New Jersey Zinc Company, 160 Front St., New York, N. Y. 
Bridgman, J. A-, The WUbur White Chemical Co., 62 Temple St., Owego, N. Y. 
Briggs, C. H., The Howard Wheat and Flour Testing Laboratory, Old Colony 

Building, Minneapolis, Minn. 
Brill, A., The Bninswick-Balke-CoUender Ca, Muskegon, Mich. 
Brock, F. P., Redmanol Chemical Products Co., 636 W. 22nd St., Chicago, 111. 
Brockway, C. P., Industrial Research Corporation, 1025 Front St., Toledo, Ohio. 
Brown, M. J., The Roessler & Hasslacher Chemical Company, Perth Amboy, N. J. 
Browne, C. A., The New York Sugar Trade Laboratory, Inc., 79 Wall St., New 

York, N. Y. 
Brownlee, W. K., Buckeye Qay Pot Co., Bassett and Ontario Sts., Toledo, Ohio. 
Brunjes, W. G., Dicks David Company, Incorporated, 22nd St. and Stewart Ave., 

Chicago Heights, 111. 
Bryson, T. A., Tolhurst Machine Works, Troy, N. Y. 
Buchanan, A. J., M. B. Chemical Co., Inc, Johnson City, Tenn. 
Bullard, Walter Gould, United Shoe Machinery Corporation, Beverly, Mass. 
Burdett, J. B., Burdett Manufacturing Company, St. Johns Court at Fulton Street, 

Chicago, 111. 
Burdick, A. S., The Abbott Laboratories, Chicago, 111. 

Burrage, A. C, Jr., Atlantic Dyestuff Company, 88 Ames Building, Boston, Mass. 
Bush, v., American Radio and Research Corporation, Medford, Mass. 
Cabot, Samuel, Samuel Cabot, Inc., 141 Milk St., Boston, Mass. 
Cady, Francis E., National Lamp Works of General Electric Company, Nela Park, 

Qeveland, Ohio. 
Calbeck, J. H., The Eagle-Picher Lead Company, 208 S. LaSalle St., Chicago, 111. 
Callow, J. M., The General Engineering Company, Incorporated, 159 Pterpont St, 

Salt Lake City, Utah. 
Campbell, J. H., Robert W. Hunt and Co., 175 W. Jackson Blvd., Chicago, 111. 
Campbell, Ross, American Writing Paper Co., Holyoke, Mass. 
Carothers, J. N., Federal Phosphorus Company, Anniston, Ala. 
Carter, Edgar B., Swan-Myers Company, 219 N. Senate Ave., Indianapolis, Ind. 
Carter, F. E., Baker & Co., Inc., Newark, N. J. 

Carveth, H. R., The Roessler & Hasslacher Chemical Company, Perth Ambpy, N. J. 
Case, Theodore W., Case Research Laboratory, Auburn, N. Y. 
Cassady, V. K., The Palmolive Company, Milwaukee, Wis. 

Catherman, R. F., C. G. Buchanan Chemical Company, Baker Ave., Norwood, Ohio. 
Cheney, G. A., A. P. Munning & Co., Matawan, N. J. 

Chittick, J. R., Jaques Manufacturing Company, 16th and Canal Sts., Chicago, 111. 
Chormann, O. I., The Pfaudler Co., Rochester, N. Y. 
Christie, R. E., Spreckels Sugar Company, 2 Pine St., San Francisco, Calif. 
Christison, Hugh, Arlington Mills, Lawrence, Mass. 
Qark, Edmund, New England Confectionery Company, 253 Summer St, Boston, 

Mass. 
Qark, F. C, American Writing Paper Co., Holyoke, Mass. 
Clark, J. F., Rochester Button Company, 300 State St., Rochester, N. Y. 
Clark, Wm. M., National Lamp Works of General Electric Company, Nela Park, 

Geveland, Ohio. 
Qements, F. O., General Motors Research Corporation, Box 745, Moraine City, 

Dayton, Ohio. 
Qevenger, Galen H., United States Smelting, Refining & Mining Company, 55 Con- 
gress St., Boston, Mass. 



124 INDUSTRIAL RESEARCH LABORATORIES 

Qifford, R. K., Kokomo Steel and Wire Co., Kolcomo, Ind. 

Qowes, G. H. A., Eli Lilly and Company, Indianapolis, Ind. 

Codwise, P. W., Byron Weston Co., Dalton, Mass. 

Coleman, A. B., The Coleman & Bell Company, Norwood, Ohio. 

Collins, T. R., Pittsburgh Plate Glass Co., Newark, N. J. 

Colpitis, E. H., Western Electric Company, Incorporated, 463 West Street, New 

York, N. Y. 
Comstock, Daniel F., Kalmus, Comstock & Wescott, Inc., 110 Brookline Ave., 

Boston, Mass. 
Comstock, G. F., Titanium Alloy Manufacturing Co., Niagara Falls, N. Y., and 

Lumen Bearing Company, Buffalo, N. Y. 
Condit, P. H., Dicks David Company, Incorporated, 22nd St. and Stewart Ave., 

Chicago Heights, 111. 
Conwell, E. L., E. L. Conwell & Co., Inc., 2024 Arch St, Philadelphia, Pa. 
Comelison, R. W., Peerless Color Company, Bound Brook, N. J. 
Costa, Charles, William R. Warner & Company, Incorporated, 113 W. 18th St., 

New York, N. Y. 
Craft, E. B., Western Electric Company, Incorporated, 4(i3 West Street, New York, 

N. Y. 
Craver, H. H., PiUshurgh Testing Laboratory, 616 Grant St, Pittsburgh, Pa. 
Crossley, M. L., The Calco Chemical Company, Bound Brook, N. J. 
Cruser, Frederick Van Dyke, The Diamond Match Co., Oswego, N. Y. 
Currier, Edward E., T. H. Quinn & Company, E. Smethport, Pa. 
Cushman, Allerton S., The Institute of Industrial Research, 19th and B Sts. N. W., 

Washington, D. C 
Dahlberg, H. W., The Great Western Sugar Company, Sugar Building, Denver, Colo. 
Dale, J. K., U. S. Food Products Corp., Peoria, 111. 

Dannerth, Frederic, The Rubber Trade Laboratory, 96 Academy St., Newark, N. J. 
Davis, Qarke E., National Biscuit Company, 409 W. Fifteenth St, New York, N. Y. 
Dean, J. Atlee, Dean Laboratories, Inc., 48th St and Walton Ave., Philadelphia, Pa. 
Delbridge, T. G., The Atlantic Refining Company, 3144 Passyunk Ave., Philadel- 
phia, Pa. 
Del Mar, William A., Habirshaw Electric Cable Company, Inc., Yonkers, N. Y. 
Dengler, F. Peter, Industrial Research Laboratories, 190 N. State St, Chicago, IlL 
Dennis, Harold, The Martin Dennis Company, 859 Summer Ave., Newark, N. J. 
D'Eustachio, G., Standard Underground Cable Company, 26 Washington St, Perth 

Amboy, N. J. 
Dewey, Bradley, Dewey & Almy Chemical Company, Harvey St., Cambridge, Mass. 
Dicken, C O., E. J. Brach and Sons, 215 W. Ohio St, Chicago, 111. 
Dickey, C. B., Corona Chemical Division, Pittsburgh Plate Glass Co., Milwaukee, 

Wis. 
Dickson, J. C, Inland Steel Company, Indiana Harbor, Ind. 
Dixon, A. F., Western Electric Company, Incorporated, 463 West Street, New York, 

N. Y. 
Doane, S. E., National Lamp Works of General Electric Company, Nela Park, 

Qeveland, Ohio. 
Dorsey, Frank M., National Lamp Works of General Electric Company, Nela Park, 

. Geveland, Ohia 
Dotterer, David R., Gibbs Preserving Company, 2303 Bostcxi St., Baltimore, Md. 
Downs, C R., The Barrett Company, Edgewater, N. J. 



INDUSTRIAL RESEARCH LABORATORIES 125 

Drogin, David, The Gray Industrial Laboratories, 961 Frelinghttysen Ave., Newark, 
N.J. 

Duggan, T. R., The Permutit Company, 440 Fourth Ave., New York, N. Y. 

Dunham, Henry G., Digestive Ferments Co., Detroit, Mich. 

Dunham, H. V., 50 E. 41st St, New York, N. Y. 

Dupont, F. M., Industrial Chemical Institute of Milwaukee, 200 Pleasant St., Mil- 
waukee, Wb. 

Durfee, Winthrop C, 516 Atlantic Ave., Boston, Mass. 

Duschak, L. H., Metals^ & Chemicals Extraction Corporation, 1014 Hohart Bldg., 
San Francisco, Calif. 

Edison, Thos. A., Thomas A. Edison Laboratory, Orange, N. J. 

Edwards, W. F., U. S. Testing Co., Inc., 316 Hudson St, New York, N. Y. 

Eichinger, Benjamin F., Bridgeman-Russell Company, 1100 W. Superior St, Duluth, 
Minn. 

Eldred, Frank R., Eli Lilly and Company, Indianapolis, Ind. 

Elliott, George K., The Lunkenheimer Co., Cincinnati, Ohio. 

Ellis, Carleton, Ellis-Foster Company, 92 Greenwood Ave., Montclair, N. J. 

Emerson, H. C, Emerson Laboratory, 145 Chestnut St, Springfield, Mass. 

Emmons, Frank W., Washburn-Crosby Co., Minneapolis, Minn. 

Enfield, W. L., National Lamp Works of General Electric Company, Nela Park, 
Qeveland, Ohio. 

Engelhardt, Herman, Sharpe & Dohme, Baltimore, Md. 

Espenhahn, E. V., The Gray Industrial Laboratories, 961 Frelinghuysen Ave., 
Newark, N. J. 

Esselen, Gustavus J., Jr., Skinner, Sherman & Esselen, Incorporated, 248 Boylston 
St, Boston 17, Mass. 

Eustis, F. A., 131 State St, Boston, Mass. 

Fahy, Frank P., 50 Church St, New York, N. Y. 

Faile, E. H., The Dorite Manufacturing Company, 116 Utah St, San Francisco^ Calif. 

Fash, R. H., Fort Worth Laboratories, Box 1008, Fort Worth, Texas. 

Fenn, Herbert B., Metakloth Co., Lodi, N. J. 

Ferguson, Louis A., Commonwealth Edison Company, 72 West Adams St., Chi- 
cago, 111. 

Fippin, E. O., National Lime Association, 918 G St N. W., Washington, D. C. 

Fisher, J. P., Doherty Research Company, Empire Division, Bartlesville, Okla. 

Fiske, Augustus H, Rumford Chemical Works, Providence, R. I. 

FitzGerald, F. A. J., The FiuGerald Laboratories, Inc., Niagara Falls, N. Y. 

Fitzgerald, F. F., American Can Company, 120 Broadway, New York, N. Y. . 

Fitzgerald, Wm. P., J. T. Baker Chemical Ca, Phillipsburg, N. J. 

Flagg, F. P., Waltham Watch Company, Waltham, Mass. 

Fleming, R. S., Merrell-Soule Laboratory, Syracuse, N. Y. 

Fogh, Carl S., Wedge Mechanical Furnace Company, Greenwich Point, Philadel- 
phia, Pa. 

Ford, Allen P., Crane Co., South Ave., Bridgeport, Conn. 

Forman, L. P., American Window Glass Co., Factory No. 1, Arnold, Pa. 

Forrest, Charles N., The Barber Asphalt Paving Company, Philadelphia, Pa. 

Fox, H. W., The Krebs Pigment and Chemical Co., Newport, Del. 

Francis, Charles K., Cosden & Company, Tulsa, Okla. 

Francis, J. M., Parke, Davis & Company, Detroit, Mich. 

Frary, Francis C, Aluminum Company of America, New Kensington, Pa. 

Frees, Herman E., The H. E. Frees Co., 2528 W. 48th Pkce, Chicago, 111. 



126 INDUSTRIAL RESEARCH LABORATORIES 

French, D. K., Dearborn Chemical Company, McCormick Building, Chicago, 111. 
Frick, F. F., Anaconda Copper Mining Co., Anaconda, Mont 
Frickstad, £. T., California Ink Company, Inc., Camelia and 4th Sts., Berkeley, Calif. 
Frohring, W. O., The Telling-Belle Vernon Company, 3825 Cedar Ave., Cleveland, 

Ohio. 
Fry, K J., Davis Chemical Products, Inc., Springfield, N. J. 
Fuller, A. D., Dextro Products, Inc., 25 Illinois St., Buffalo, N. Y. 
Fuller, A. V., The American Sugar Refining Company, 117 Wall St., New York, 

N. Y. 
Gage, R. M., The Portage Rubber Co., Barberton, Ohio. 

Gane, E. H., McKesson & Robbins, Incorporated, 97 Fulton St., New York, N. Y. 
Gardner, H. F., The Beaver Board Companies, Beaver Road, Buffalo, N. Y. 
Gatward, W. A., Hoskins Manufacturing Company, Lawton Ave. at Buchanan, 

Detroit, Mich. 
Geer, W. C, The B. F. Goodrich Company, Akron, Ohio. 
Gegenheimer, R. E., The Mathieson Alkali Works (Inc.), Niagara Falls, N. Y. 
George, Harry, Chase Metal Works, Waterbury, Conn. 
Gcrstle, John, The Electro Chemical Company, Dayton, Ohio. 
Gcssler, A. E., Ultro Chemical Corporation, 236 46th St., Brooklyn, N. Y. 
Gibbons, John T., Feculose Co. of America, Ayer, Mass. 
Gill, James P., The Vanadium-Alloys Steel Co., Latrobe, Pa. 
Gilligan, F. P., The Henry Souther Engineering Co., 11 Laurel St., Hartford, Conn. 
Ginsburg, S., National Gum & Mica Co., 12 West End Ave., New York, N. Y. 
Given, G. C, Atlas Powder Co., Stamford, Conn. 
Glancy, Warren E., Hood Rubber Company, Watertown, Mass. 
Gnadinger, C. B., McLaughlin Gormley King Co., 1715 Fifth St. S. £., Minneapolis, 

Minn. 
Goldstein, William, Radiant Dye & Color Works, 2837 W. 21st St., Brooklyn, N. Y. 
Goldthwait, Charles F., Klearflax Linen Rug Company, 63rd and Grand Aves., West 

Duluth, Minn. 
Goodale, Frank, Pure Oil Company, York and McLean Aves., Cincinnati, Ohio. 
Graber, Howard T., Digestive Ferments Co., Detroit, Mich. 

Gravell, J. H., American Chemical Paint Company, 1126 S. 11th St., Philadelphia, Pa. 
Gravely, J. S., Winchester Repeating Arms Co., New Haven, Conn. 
Gray, Arthur W., The L. D. Caulk Company, Milford, Del. 
Gray, Thomas T., The Gray Industrial Laboratories, 961 Frelinghuysen Ave., 

Newark, N. J. 
Greenwood, F. E., Joseph H. Wallace & Co., Webbs Hill, Stamford, Conn., 

R. F. D. 29. 
Greenwood, H. D., United States Metals Refining Co., Chrome, N. J. 
Grondahl, L. O., Union Switch & Signal Company, Swissvale, Pa. 
Gross, E. L., The Pcrolin Company of America, 1112 W. 37th St., Chicago, 111. 
Grosvenor, Wm. M., 50 E. 41st St., New York, N. Y. 
Grotts, F. W., The Holt Manufacturing Company, Peoria, 111. 
Grunenberg, Hubert, Newark Industrial Laboratories, 96 Academy St, Newark, N. J. 
Gundlach, H. R., The Interocean Oil Company, East Brooklsm, Baltimore, Md. 
Haldenstein, A. A., National Gum & Mica Co., 12 West End Ave., New York, N. Y. 
Hale, J. E., Firestone Tire & Rubber Company, Akron, Ohio. 
Halley, Clifford D., Acme White Lead & Color Works, Detroit, Mich. 
Hamilton, Herbert W., The White Tar Company of New Jersey, Inc., Newark, N. J. 
Handy, Jas. O., Pittsburgh Testing Laboratory, 616 Grant St., Pittsburgh, Pa. 



INDUSTRIAL RESEARCH LABORATORIES 127 

Hanson, H. H., Eastern Manufacturing Company, Bangor, Me. 

Hargrove, G. C, The Gray Industrial Laboratories, 961 Frelinghuysen Ave., Newark, 

N.J. 
Harlow, J. B., Western Electric Company, Incorporated, 463 West Street, New 

York, N. Y. 
Harris, C. P., Tower Manufacturing Co., Inc., 85 Doremus Ave., Newark, N. J. 
Harris, J. W., Western Electric Company, Incorporated, 463 West Street, New 

York, N. Y. 
Hartmann, M. L., The Carborundum Company, Niagara Falls, N. Y. 
Hartong, R. C, The Goodyear Tire & Rubber Company, Akron, Ohio. 
Hayes, Hammond V., 84 State St., Boston, Mass. 

Heim, F. D., Charles M. Childs & Co., Inc., 41 Summit St., Brooklyn, N. Y. 
Heinrich, £. O., Heinrich Laboratories of Applied Chemistry, 1001 Oxford St., 

Berkeley, Calif. 
Hendry, W. F., Western Electric Company, Incorporated, 463 West Street, New 

York, N. Y. 
Hentus, Max, Wahl-Henius Institute, Incorporated, 1135 Fullerton Ave., Chicago, 111. 
Heyl, Frederick W., The Upjohn Company, Kalamazoo, Mich. 
Higgins, C. H., Sears, Roebuck and Co., Chicago, 111. 
Higley, H. V., Ansul Chemical Company, Marinette, Wis. 
Hill, R. L., Atlas Powder Co., Reynolds, Pa. 

Hillman, V. E., Crompton & Knowles Loom Works, Worcester, Mass. 
Hilton, Robert W., The Ault & Wiborg Company, Cincinnati, Ohio. 
Hinck, C, Lehn & Fink, Inc., 192 Bloomfield Ave., Bloomfield, N. J. 
Hirsch, Alcan, The Hirsch Laboratories, Inc, 593 Irving Ave., Brooklyn, N. Y. 
Hirschfield, C. F., The Detroit Edison Company, Detroit, Mich. 
Hitchins, Alfred B., Ansco Company, Binghamton, N. Y. 
Hobbs, G. M., Sears, Roebuck and Co., Chicago, 111. 

Hochstadter, Irving, Hochstadter Laboratories, 227 Frcxit St., New York, N. Y. 
Hocker, Ivan S., The National Laboratories, 1313 H St N. W., Washington, D. C. 
Holmes, Fletcher B., E. I. du Pont, de Nemours & Company, Box 525, Wilmington, 

Del. 
Holmes, M. E., National Lime Association, 918 G St. N. W., Washington, D. C. 
Holtz, F. C, Sangamo Electric Company, Springfield, 111. 

Holz, Robert, The Richardson Company, 26th and Lake Sts., Melrose Park, 111. 
Hooker, A. H., Hooker Electrochemical Company, Niagara Falls, N. Y. 
Hooper, C. W., H. A. Metz Laboratories, Inc., 642 Pacific St., Brooklyn, N. Y. 
Houghton, A. C, Semet-Solvay Co., Syracuse, N. Y. 
Houghton, E. M., Parke, Davis & Company, Detroit, Mich. 
Houseman, Percy A., MacAndrews & Forbes Company, 3rd St and Jefferson Ave., 

Camden, N. J. 
Howard, Frank A., Standard Oil Company, 26 Broadway, New York, N. Y. 
Howard, Henry, Grasselli Chemical Company, 130p Guardian Bldg., Cleveland, Ohio. 
Howell, Frank B., American Radiator Company, Buffalo, N. Y. 
Hoyt, L. F., Larkin Co., 680 Seneca St, Buffalo, N. Y. 
Hudson, R. M., The Holt Manufacturing Company, Peoria, 111. 
Humble, Joseph M., American Diamalt Company, 419 Plum St., Cincinnati, Ohio. 
Hutchinson, W. T., Condensite Company of America, Bloomfield, N. J. 
Hyde, Edward P., National Lamp Works of General Electric Company, Nela Park, 

Qeveland, Ohio. 
Isaacs, A. S., The Northwestern Chemical Co., Marietta, Ohio. 



128 INDUSTRIAL RESEARCH LABORATORIES 

Jackson, R. P., Westinghouse Electric & Manufacturing Company, East Pitts- 
burgh, Pa. 

Jacobs, B. R., National Cereal Products Laboratories, 1731 H St. N. W., Wash- 
ington, D. C. 

James, U. S., James Ore Concentrator Co., 35 Runyon St, Newark, N. J. 

Janney, Thomas A., Utah Copper Company, Garfield, Utah. 

Jarvis, Ernest G., McNab & Harlin Manufacturing Co., 440 Straight St, Paterson, 
N.J. 

Jefferson, H. F., Kilboume & Clark Manufacturing Company, Seattle, Wash. 

Jenkins, L. A., The Kolynos Co., New Haven, Conn. 

Jcwett, F. B., Western Electric Company, Incorporated, 463 West Street, New 
York. N. Y. 

Johns, C. O., Standard Oil Company, Linden, N. J. 

Johnson, Charles Morris, Crucible Steel Company of America, Pittsburgh, Pa. 

Jones, Minor C K., Consolidated Gas, Electric Light and Power Company of Balti- 
more, Spring Gardens Plant, Baltimore, Md. 

Jones, R. L., Western Electric Company, Incorporated, 463 West Street, New 
York, N. Y. 

Josephson, Edgar, The Pantasote Leather Company, Passaic, N. J. 

Judd, C W., Chemical Economy Company, 1640 N. Spring St, Los Angeles, Calif. 

Jurrissen, A. W., Martinez Refinery, Shell Ca of California, Martinez, Calif. 

Kalmus, Herbert T., Kalmus, Comstock & Wescott, Inc., 110 Brookline Ave., Boston, 
Mass. 

Kamm, Oliver, Parke, Davis & Company, Detroit, Mich. 

Kaplan, Philip, Reliance Aniline & Chemical Co., Incorporated, Poughkeepsie, N. Y. 

Kasley, A. T., Westinghouse Electric & Manufacturing Company, Essington, Pa. 

Keller, L., Western Electric Company, Incorporated, 463 West Street, New York, 
N. Y. 

Kellner, Hermann, Bausch & Lomb Optical Company, Rochester, N. Y. 

Kersey, K. S., The P. W. Drackett & Sons Co., Cincinnati, Ohio. 

Kettering, C F., General Motors Research Corporation, Box 745, Moraine City, 
Dayton, Ohio. 

Keuffel, Carl, Keuffel & Esser Co., Hoboken, N. J. 

Kiefer, H. E., Monroe Drug Company, Bottom Road, Quincy, 111. 

Kilbom, K. B., The Goodyear Tire & Rubber Company, Akron, Ohio. 

Kilmer, Fred B., Johnson & Johnson, New Brunswick, N. J. 

King, W. E., Beebe Laboratories, Inc., 161 3rd St, St Paul, Minn. 

Kingsbury, H. P. D., Redlands Fruit Products Company, Redlands, Calif. 

Kleimenhagen, Karl, Cants Chemical Company, La Salle, 111. 

Kleinfeldt, H. F., Abb6 Engineering Company, 230 Java St, Brooklyn, N. Y. 

Klopsteg, Paul E., Central Scientific Company, 460 East Ohio St, Chicago, 111. 

Koch, George T., The Ohio Fuel Supply Company, Utica, Ohio. 

Kohout, Jerome F., Commercial Testing and Engineering Co., 1785 Old Colony 
Bldg., Chicago, 111. 

Kolb, Frank P., Bausch & Lomb Optical Company, Rochester, N. Y. 

Kraeger, J. F., The Federal Products Company, 7818 Lockland Ave., Cincinnati, Ohio. 

Kratz, G. D., The Falls Rubber Company, Cuyahoga Falls, Ohio. 

Kraus, Charles E., Kraus Research Laboratories, Inc, 130 Pearl St., New York, N. Y. 

Lacy, B. S., The Roessler & Hasslacher Chemical Company, Perth Amboy, N. J. 

Lamar, William R., Lyster Chemical Company, Inc., Passaic Junction, N. J. 

Landis, W. S., American Cyanamid Company, 511 Fifth Ave., New York, N. Y. 



INDUSTRIAL RESEARCH LABORATORIES 129 

Landman, Everett S., United States Bronze Powder Works, Inc., Closter, N. J. 

Langfeld, Millard, The Cudahy Packing Co., South Side Station, Omaha, Nebr. 

Langston, R. E., Wasme Oil Tank and Pump Co., Ft. Wasme, Ind. 

Laucks, I. P., I. F. Laucks, Inc., 99 Marion St., Seattle, Wash. 

Lavett, Charles, Buffalo Foundry and Machine Co., 1543 Fillmore Ave., Buffalo, N. Y. 

Lee, O. Ivan, T. M. & G. Chemical Co., 517 Cortlandt St, Belleville, N. J. 

LeTellier, A. M., The Peerless Drawn Steel Company, Massillon, Ohio. 

Levi, Louis R, Pfister & Vogel Leather Co., 447 Virginia St., Milwaukee, Wis. 

Levin, I. H., The Electrolabs Company, 2635 Penn Ave., Pittsburgh, Pa. 

Lewis, Charles H., W. H. Long & Co., Inc., 244 Canal St., New York, N. Y. 

Liddell, Donald M., Weld and Liddell, 961 Frelinghuysen Ave., Newark, N. J. 

Linch, H. A., The Dorr Comptoy, Westport Mill, Westport, Conn. 

Lincoln, E. S., E. S. Lincoln, Inc., 534 Congress St., Portland, Me. 

Linden, H. E., Beckman and Linden Engineering Corporation, Balboa Building, 
San Francisco, Calif. 

Littlefield, E. E., Littlefield Laboratories Co., Seattle, Wash. 

Locke, Charles E., Richards & Locke, 69 Massachusetts Ave., Cambridge 39, Mass. 

Lockhart, L. B., LocHhart Laboratories, 33^ Auburn Ave., Atlanta, Ga. 

Long, C. P., The Globe Soap Company, St. Bernard, Ohio. 

Loomis, N. E., Standard Oil Company, Linden, N. J. 

Loudenbeck, H. C, Union Switch & Signal Company, Swissvale, Pa. 

Luckiesh, M., National Lamp Works of General Electric Company, Nela Park, 
Qeveland, Ohio. 

Lunn, Charles A., Consolidated Gas Company of New York, Lawrence Point, 
Astoria, N. Y. 

Lyng, J. J., Western Electric Company, Incorporated, 463 West Street, New York, 
N. Y. 

Lyon, P. S., H. S. B. W. Cochrane Corporation, 17th and Allegheny Ave., Phila- 
delphia, Pa. 

Lyster, T. L. B., Hooker Electrochemical Company, Niagara Falls, N. Y. 

Maas, Arthur R., A. R. Maas Chemical Company, 306 E. 8th St, Los Angeles, Calif. 

Macgregor, Robert W., Ernest Scott & Company, Fall River, Mass. 

Magruder, E. W., F. S. Royster Guano Company, Norfolk, Va. 

Mailey, R. D., Cooper Hewitt Electric Company, 730 Grand St, Hoboken, N. J. 

Malmstrom, A., Wilckes, Martin, Wilckes Company, head of Pine St., Camden, N. J. 

Marcus, M. M., Rhode Island Malleable Iron Works, Hillsgrove, R. I. 

Markush, Eugene A., Pharma-Chemical Corporation, Baycmne, N. J. 

Marsh, W. J., Hooker Electrochemical Company, Niagara Falls, N. Y. 

Marshall, A. E., The Davison Chemical Company, Baltimore, Md. 

Marx, Ernest A., Pyro-Non Paint Co., Inc, 505 Driggs Ave., Brooklyn, N. Y. 

Mathias, L. D., Victor Chemical Works, Fisher Building, Chicago, 111. 

May, M. S., Speer Carbon Company, St. Marys, Pa. 

May, Otto B., May Chemical Works, 204 Niagara St, Newark, N. J. 

Maynard, T. Poole, Atlanta, Ga. 

McQave, James M., Western Research Corporation, Incorporated, 514 18th St, 
Denver, Colo. 

McCleary, F. K, Dodge Brothers, Detroit, Mich. 

McCoy, H. N., Lindsay Light Company, 161 E. Grand Ave., Chicago, 111. 

McDougal, T. G., Champion Ignition Company, Flint, Mich. 

Mcllhiney, Parker C, 50 E. 41st St, New York, N. Y. 

McKee, C. R., United States Glue Co., Milwaukee, Wis. 



130 INDUSTRIAL RESEARCH LABORATORIES 

Mees, C. E. K., Eastman Kodak G>mpany, Rochester, N. Y. 

Meredith, S. C, Western Sugar Refinery, foot 23rd St, San Francisco, Calif. 

Merka, Paul D., The International Nickel Company, Bayonne, N. J. 

Merrill, Edward C, United Drug Company, Boston, Mass. 

Merrill, W. H., Underwriters' Laboratories, 207 E. Ohio St., Chicago, 111. 

Meston, A. F., The DeLaval Separator Co., 165 Broadway, New York, N. Y. 

Metz, G. P., H. A. Metz Laboratories, Inc., 642 Pacific St., Brooklyn, N. Y. 

Meyer, A. H., Providence Gas Company, Incorporated, Providence, R. I. 

Milbnm, Lessiter C, The Glen L. Martin Company, 16800 St. Clair Ave., Cleveland, 
Ohio. 

Miles, E. J., The Studebaker Corporation, Detroit, Mich. 

Miller, A. H., Midvale Steel and Ordnance Company, Nicetown Works, Philadel- 
phia, Pa. 

Miller, J., The Pierce-Arrow Motor Car Company, Elmwood Ave., Buffalo, N. Y. 

Millner, James A., Imperial Belting Company, 400 N. Lincoln St., Chicago, 111. 

Miner, C. S., The Miner Laboratories, 9 S. Qinton St, Chicago, 111. 

Miner, Harlan S., Welsbach Company, Gloucester, N. J. 

Mitchell, Frank H., Dill & Collins Co., Richmond and Tioga Sts., Philadelphia, Pa. 

Mitchell-Roberts, J. F., Oliver Continuous Filter Co., No. 9 Red Lion Passage, 
Holbom, London, W. C. L, England. 

Mojonnier, J. J., Mojonnier Bros. Co., 73^ W. Jackson Boulevard, Chicago, 111. 

Mojonnier, Timothy, Mojonnier Bros. Co., 739 W. Jackson Boulevard, Chicago, III. 

Montgomery, John A., The Borromite Co. of America, 54 E. 18th St, Chicago, 111. 

Montgomery, John K., Theodore Meyer, 213 S. 10th St, Philadelphia, Pa. 

Moody, C. S., Minneapolis Steel and Machinery Co., 2854 Minnehaha Ave., Minne- 
apolis, Minn. 

Moore, Hugh K., Brown Company, Berlin, N. H. 

Moore, Thomas E., The Ransom & Randolph Co., 518 Jefferson Ave., Toledo, Ohio. 

Morgan, R. H., Industrial Works, Bay City, Mich. 

Mork, H. S., Chemical Products Company, 44 K St., South Boston, Mass. 

Morrison, H. J., The Procter & Gamble Co., Ivorydale, Ohio. 

Morse, H. E., The Goodyear Tire & Rubber Company, Akron, Ohio. 

Morton, H. A., The Miller Rubber Co., Akron, Ohio. 

Mothwurf, Arthur F. F., Garfield Aniline Works, Inc., Garfield, N. J. 

Mowry, C. W., Factory Mutual Laboratories, 31 Milk St., Boston, Mass. 

Mullin, Chas. E., Eavenson*& Levering Co., cor. 3rd and Jackson Sts., Camden, N.J. 

Mumford, R. W., American Trona Corporation, Trona, Calif. 

Munn, W. Faitoute, 518 Main St, E. Orange, N. J. 

Murphy, W. B., F. J. Lewis Manufacturing Co., 2513 S. Robey St, Chicago, III. 

Myers, C. N., H. A. Metz Laboratories, Inc., 642 Pacific St, Brooklyn, N. Y. 

Myers, R. K, Westinghouse Lamp Ca, Bloomfield, N. J. 

Napolitan, Frank J., Davis- Bournonville Company, Jersey City, N. J. 

Newlands, J. A., The Henry Souther Engineering Co., 11 Laurel St, Hartford, Conn. 

Nichols, B., Schaeffer Brothers & Powell Manufacturing Company, 102 Barton St., 
St. Louis, Mo. 

Norman, G. M., Hercules Powder Co., Wilmington, Del. 

Northrup, H. B., Diamond Chain & Manufacturing Company, 502 Kentucky Ave., 
Indianapolis, Ind. 

Nowak, C. A., Nowak Chemical Laboratories, 518 Chemical Building, St. Louis, Mo. 

Oldham, K W., Firestone Tire & Rubber Company, Akron, Ohio. 

Oliver, E. L., Oliver Continuous Filter Co., 503 Market St, San Francisco, Calif. 



INDUSTRIAL RESEARCH LABORATORIES 131 

O'Ncfl, F. W., Ingwsoll-Rand Company, 11 Broadway, New York, N. Y. 

Ott, Harry G., Spencer Lens Company, Buffalo, N. Y. 

Pack, Charles, Doehler Die-Casting Co., Court, Ninth and Huntington Streets, 
Brooklyn, N. Y. 

Page, Carl M., Riverbank Laboratories, Geneva, 111. 

Palmer, R. C, The Newport Company, Pensacola, Fla. 

Palmer, W. R., Columbia Graphophone Manufacturing Company, Bridgeport, Conn. 

Pastemack, Richard, Chas. Pfizer & Co., Inc., 11 Bartlett St., Brooklyn, N. Y. 

Pease, H. D., Pease Laboratories, 39 West 38th St., New York, N. Y. 

Pettee, C L. W.,' Laboratories of Charles L. W. Pettee, 112 High St., Hartford, Conn. 

Pfanstiehl, Carl, Special Chemicals Company, Highland Park, 111. 

Philipp, H., Dicks David Company, Incorporated, 22nd St. and Stewart Ave., Chi- 
cago Heights, 111. 

Phillips, P. M., Frank S. Betz Company, Henry and Hoffman Sts., Hammond, Ind. 

Phillips, R. O., New York Quebracho Extract Company, Incorporated, Greene and 
West Sts., Greenpoint, Brooklyn, N. Y. 

Poetschke, Paul, The L. D. Caulk Company, Mil ford, Del. 

Porro, Thomas J., Porro Biological Laboratories, 625 Puget Sound Bank Bldg., 
Tacoma, Wash. 

Porst, Christian E. G., Com Products Refining Company, Edgewater, N. J. 

Porter, F. B., Fort Worth Laboratories, Box 1008, Fort Worth, Texas. 

Porter, Horace C, 1833 Chestnut St., Philadelphia, Pa. 

Potter, Paul D., Sprague, Warner & Company, 600 West Erie St., Chicago, 111. 

Powell, J. R., Armour Glue Works, 31st Place imd Benson St., Chicago, 111. 

Pratt, Lester A., Merrimac Chemical Company, North Wobum, Mass. 

Pressell, George W., E. F. Houghton & Co., 240 W. Somerset St, Philadelphia, Pa. 

Prochazka, John, Central Dyestuff and Chemical Co., Plum Point Lane, Newark, N. J. 

Pushee, H. B., General Tire & Rubber Co., Akron, Ohio. 

Putnam, W. P., The Detroit Testing Laboratory, 3726 Woodward Ave., Detroit, Mich. 

Quinn, Don L., Chicago Mill and Lumber Company, Conway Bldg., Chieago, lit 

Ramsdell, Bartlett, Babcock Testing Laboratory, 803 Ridge Road, Lackawanna, N. Y. 

Randall, J. E., National Lamp Works of General Electric Company, Nela Park, 
Geveland, Ohio. 

Redman, L. V., Redmanol Chemical Products Co., 636 W. 22nd St, Chicago, 111. 

Reese, Charles L, E. I. du Pont, de Nemours & Company, Wilmington, Del. 

Reese, W. J., Peet Bros. Mfg. Co., Kansas City, Kans. 

Reichel, John, H. K. Mulford Company, Glenolden, Pa. 

Rentschler, H. C, Westinghouse Lamp Co., Bloomfield, N. J. 

Rhael, Edward W., Foster-Heaton Company, 27 Badger Ave., Newark, N. J. 

Rice, F. E., Nestl^'s Food Company, Incorporated, Ithaca, N. Y. 

Richards, Robert H., Richards & Locke, 69 Massachusetts Ave., Cambridge 39, Mass. 

Richardson, William D., Swift & Company, Chicago, 111. 

Riddle, Frank H., Champion Porcelain Company, Detroit, Mich. 

Riker, A., Jr., Butterworth-Judson Corporation, Newark, N. J. 

Riley, O. B., Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa. 

Risley, R. R, Stockham Pipe & Fittings Co., Birmingham, Ala. 

Robbins, William K., Amoskeag Manufacturing Company, Manchester, N. H. 

Roberts, L. E., American Writing Paper Co., Holyoke, Mass. 

Robinson, C. I., Standard Oil Company, Linden, N. J. 

Rodman, Hugh, Rodman Chemical Company, Verona, Pa. 

Roeg, Louis M., Musher and Company, Incorporated, Baltimore, Md. 



132 INDUSTRIAL RESEARCH LABORATORIES 

Rogers, Allen, Hyco Fuel Products Corporation, Edgewater, N. J. 
Rogers, F. H., The William Cramp & Sons Ship & Engine Buildmg Co., Philadel- 
phia, Pa. 
Rogers, F. M., Standard Oil Company of Indiana, Whiting, Ind. 
Rogers, J. S., International Shoe Co., Morganton, N. C. 
Romer, J. B., The Babcock & Wilcox Co., Bayonne, N. J. 
Rosengarten, George D., The Powers- Weightman-Rosengarten Company, 916 Parrish 

St., Philadelphia, Pa. 
Rosenstein, Ludwig, Great Western Electro-Chemical Company, 9 Main St., San 

Francisco, Calif. 
Ross, F. W., Art in Buttons, Incorporated, Rochester, N. Y. 
Rother, Willard, Buffalo Foundry and Machine Co., 1543 Fillmore Ave., Buffalo, 

N. Y. 
Ruddiman, Edsel A., John T. Milliken and Co., 217 Cedar St, St. Louis, Mo. 
Ruppel, Henry E. K., Gillette Safety Razor Co., 47 W. 1st St, Boston, Mass. 
Rykenboer, E. A., The Roessler & Hasslacher Chemical Company, Perth Amboy, N. J. 
Sabine, Paul E., Wallace Clement Sabine Laboratory, Riverbank, Geneva, 111. 
Saklatwalla, B. D., Vanadium Corporation of America, Bridgeville, Pa. 
Salathe, F., The Western Gas Construction Company, 1429 Buchanan St, Ft Wayne, 

Ind. 
Sammet, C. Frank, Crane & Co., Dalton, Mass. 
Sanborn, Justus C, Strathmore Paper Company, Mittineague, Mass. 
Saums, H. L., Pyrolectric Instrument Company, 636 E. State St., Trenton, N. J. 
Saunders, Harold F., The Glysyn Corporation, Bound Brook, N. J. 
Schaefer, George L., The New York Quinine & Chemical Works, Incorporated, 

135 William St, New York, N. Y. 
Schenck, P. D., The Duriron Company, Inc., N. Findlay St, Dayton, Ohio. 
Schlesinger, W. A., The Radium Company of Colorado, Inc., 18th and Blake Sts., 

Denver, Colo. 
Schlichting, Emil, Industrial Testing Laboratories, 402 West 23rd St., New York, 

N. Y. 
Schmid, M. H., United Alloy Steel Corporation, Canton, Ohio. 
Schmidt, A. H., Universal Aniline Dyes and Chemical Ca, 11th and Davis Sts., 

S. Milwaukee, Wis. 
Schneller, M. A., The Nulomoline Company, 111 Wall St, New York, N. Y. 
Schwartz, H. A., The National Malleable Castings Company, 10600 Quincey Ave., 

Qeveland, Ohio. 
Schwarz, Robert, Schwarz Laboratories, 113 Hudson St, New York, N. Y. 
Schwenk, N. H., The William Cramp & Sons Ship & Engine Building Co., Phila- 
delphia, Pa. 
Scott, A. A., Nestl6's Food Company, Incorporated, 130 William St, New York, 

N. Y. 
Scott, John G., Porro Biological Laboratories, 625 Puget Sound Bank Bldg., Tacoma, 

Wash. 
Seabury, R. W., Boonton Rubber Manufacturing Company, Boonton, N. J. 
Seibert, F. M., Gulf Pipe Line Company, Houston, Texas. 
Selke, George H., The Milwaukee Coke & Gas Company, 1st National Bank Bldg., 

Milwaukee, Wis. 
Seydel, Paul, Seydel Manufactunng Company, Jersey City, N. J. 
Sharp, Clayton H., Electrical Testing Laboratories, 80th St and East End Ave., 

New York. N. Y. 



INDUSTRIAL RESEARCH LABORATORIES 133 

Sharp, Donald £., Spencer Lens G>nipany, Hamburg, N. Y. 

Shcard, Charles, American Optical G)mpany, Southbridge, Mass. 

Sbemdal, A. E., H. A. Metz Laboratories, Inc., 642 Pacific St., Brooklyn, N. Y. 

Sherwood, C. M., Hercules Powder Co., Brunswick, Ga. 

Shively, W. R, The Goodyear Tire & Rubber Company, Akron, Ohio. 

Shoeld, M., Armour Fertilizer Works, 209 W. Jackson Blvd., Chicago, 111. 

Shrceve, H. E., Western Electric Company, Incorporated, 463 West St., New York, 

N. Y. 
Simon, Arthur, The Cutler-Hammer Mfg. Co., Milwaukee, Wis. 
Simon, C. K., Dye Products & Chemical Company, Inc., 200 5th Ave., New York, 

N. Y. 
Simons, John P., Saginaw Salt Products Co., Saginaw, Mich. 
Singer, Henry H., Radium Limited, U. S. A., 2 W. 45th St., New York, N. Y. 
Singmaster, J. A., The New Jersey Zinc Company, 160 Front St, New York, N. Y. 
Skidgell, Chas. E., International Silver Company, Meriden, Conn. 
Skinner, C. K, Westinghouse Electric & Manufacturing Company, East Pitts- 
burgh, Pa. 
Skowronski, S., Raritan Copper Works, Perth Amboy, N. J. 
Sladek, George E., Beaver Falls Art Tile Company, Beaver Falls, Pa. 
Slaght, W., The Pierce-Arrow Motor Car Company, Elmwood Ave., Buffalo, N. Y. 
Smith, E. B., Florida Wood Products Co., Jacksonville, Fla. 

Smith, Irving B., Leeds & Northrup Company, 4901 Stenton Ave., Philadelphia, Pa. 
Smith, R. B., Hercules Powder Co., Emporium, Pa. 
Smith, W. C, United States Metals Refinuig Co., Chrome, N. J. 
Snell, H. Sterling, William Heap & Sons, Grand Haven, Mich. 
Snook, H. C, Western Electric Company, Incorporated, 463 West St., New York, 

N.Y. 
Speller, F. N., National Tube Company, Frick Building, Pittsburgh, Pa. 
Sperr, F. W., Jr., The Koppers Company, Pittsburgh, Pa. 
Sperry, D. R., D. R. Sperry & Co., Batavia, 111. 
Spring, L. W., Crane Co., 836 South Michigan Ave., Chicago, 111. 
Squier, C W., The Harrison Mfg. Co., 55 Union St, Rahway, N. J. 
Stanforth, Richard, Art in Buttons, Incorporated, Rochester, N. Y. 
Stein, L., Dehls & Stein, 237 South St, Newark, N. J. 
Stevens, A. L., Lakeview Laboratories, 2 Jersey St, Buffalo, N. Y. 
Stevenson, Earl P., Arthur D. Little, Inc., 30 Charles River Road, Cambridge 39, 

Mass. 
Stoddard, W. B., Hochstadter Laboratories, 227 Front St., New York, N. Y. 
Strong, W. W., The Scientific Instrument and Electrical Machine Company, 500 S. 

York St., Mechanicsburg, Pa. 
Stull, W. N., Mallinckrodt Chemical Works, St Louis, Mo. 
Stupp, C. G., The Barrett Company, Edgewater, N. J. 
Sturtevant, W. L., The Manhattan Rubber Mfg. Ca, Passaic, N. J. 
Styri, Haakon, S. K. F. Industries, Inc., Front St and Erie Ave., Philadelphia, Pa. 
Sullivan, E. C, Coming Glass Works, Coming, N. Y. 
Sundstrom, Carl, The Solvay Process Company, Syracuse, N. Y. 
Sutermeister, E., Cumberland Mills, Cumberland Mills, Me. 
Swart, W. G., Mesabi Iron Company, Babbitt, Minn. 
Taber, Harry P., American Chemical and Manufacturing Corporation, Cranford, 

N.J. 



134 INDUSTRIAL RESEARCH LABORATORIES 

Taggart, Arthur F., Taggart and Yerxa, 165 Divisicxi St., New Haven, Conn. 

Takamine, Jokichi, Takamine Laboratory, Inc., Gifton, N. J. 

Tanberg, A. P., E. I. du Pont, de Nemours & Company, Henry Qay, Del. 

Taub, Joel, The Utility Color ft. Chemical Co.. 395 Frelinghuysen Ave., Newark, N. J. 

Teeple, John E., SO E. 41st St.. New York, N. Y. 

Temple, Sterling, The Roessler ft Hasslacher Chemical Company, Perth Amboy. N. J. 

Thomas. John F., Berry Brothers, Inc., Detroit, Mich. 

Thompson, Firman, Bowker Insecticide Company, Everett. Mass. 

Thompson, Gustave W., National Lead Company, 129 York St., Brooklyn, N. Y. 

Thorburn, A. D., Swan-Myers Company, 219 N. Senate Ave., Indianapolis, Ind. 

Thurston, S. R., Bethlehem Shipbuilding Corporation, Ltd., Union Plant, San Fran- 
cisco, Calif. 

Titus, E. G., Utah-Idaho Sugar Company, Salt Lake City, Utah. 

Toch. Maximilian, Toch Brothers, 320 Fifth Ave., New York, N. Y. 

Tolman, L. M., Wilson & Co., Chicago, 111. 

Uhlig, E. C, The Brooklyn Union Gas Company, 176 Remsen St, Brooklyn, N. Y. 

Unger, J. S., Carnegie Steel Company, 1054 Frick Annex Building, Pittsburgh, Pa. 

Vail, James G., Philadelphia Quartz Company, Philadelphia, Pa. 

Van Buskirk, J. V., Belden Manufacturing Company, 23rd St. and Western Ave., 
Chicago, 111. 

Van Marie, D. J., Buffalo Foundry and Machine Co., 1543 Fillmore Ave., Buffalo, 
N. Y. 

Van Schaack, R. H., Jr., Van Schaack Brothers Chemical Works, Inc., 3358 Avon- 
dale Ave., Chicago, 111. 

Vollertsen, J. J., Morris ft Company, Union Stock Yards, Chicago, 111. 

Vosburgh, Warren C, The Eppley Laboratory, 12 Sheffield Ave., Newport, R. I. 

Walker, R. Gordon, Oliver Continuous Filter Co., 226 E. 41st St., New York, N. Y. 

Wallace, C. F., Wallace ft Tiernan Co., Inc., Box 178, Newark, N. J. 

Walters, A. L., Eli Lilly and Company, Indianapolis, Ind. 

Watkins, J. A., American Blower Company, 6004 Russell St., Detroit, Mich. 

Webster, W. R., Bridgeport Brass Company, Bridgeport, Conn. 

Weir, J. W., Ventura Refining Company, Fillmore, Calif. 

Weirick, Elizabeth, Sears, Roebuck and Co., Chicago, 111. 

Weiss, J. M., The Barrett Company, 40 Rector St., New York, N. Y. 

Weith, A. J., Redmanol Chemical Products Co., 636 W. 22nd St., Chicago, 111. 

Welch, H. v., Western Precipitation Company, 1016 W. Ninth St., Los Angeles, 
aiif. 

Wells, Raymond, Homer, N. Y. 

Wescott, E. W., Kalmus, Comstock ft Wescott, Inc., 110 Brookline Ave., Boston, 
Mass. 

Westoo, Robert S., Weston & Sampson, 14 Beacon St., Bpston, Mass. 

Wheat, J. C, Industrial Works, Bay City, Mich. 

Wheeler, H. J., The American Agricultural Chemical Company, Carteret, N. J. 

Wheeler, T. L., Wheeler ft Woodruff, 280 Madison Ave., New York, N. Y. 

Whitney, Willis R., General Electric Company, Schenectady, N. Y. 

WhiUen, G. R., The J. O. Whitten Company, Cross St., Winchester, Mass. 

Whittington, F. G., Stewart- Warner Speedometer Corporation, Chicago, 111. 

Wiley, Samuel W., Wiley ft Company, Inc., 904 N. Calvert St., Baltimore, Md. 

Wille, H. v.. The Baldwin Locomotive Works, Philadelphia, Pa. 

Williamson, A. M., Acheson Graphite Company, Niagara Falls, N. Y. 

Wilson, C P., California Fruit Growers Exchange, Box 518, Corona, Calif. 



INDUSTRIAL RESEARCH LABORATORIES 135 

Wilson, £. A., E. I. du Pont, de Nemours & Company, Arlington, N. J. 

Wilson, Fred D., The National Association of Corrugated and Fibre Box Manufac- 
turers, 1821 Republic Building, Chicago, 111. 

Wilson, John Arthur, A. F. Gallun & Sons Co., Milwaukee, Wis. 

Winther, H., Industrial testing Laboratories, 402 West 23rd St, New York, N. Y. 

Wisdom, Roy H., Stamford Dyewood Company, Stamford, Conn. 

Witt, J. C, Structural Materials Research Laboratory, Lewis Institute, 1951 W. 
Madison St., Chicago, 111. 

Woiski, B., Lumen Bearing Company, Buffalo, N. Y. 

Wolfe, Wm. S., The Goodyear Tire & Rubber Company, Akron, Ohio. 

Wolgemuth, L. E., Sears, Roebuck and Co., Chicago, 111. 

Woltersdorf, A. H., Pittsburgh Plate Glass Co., Milwaukee, Wis. 

Woodbury, C. A., E. I. du Pont, de Nemours & Company, Box 424, Chester, Pa. 

Woolson, L. M., Packard Motor Car Company, Detroit, Mich. 

Worth, Barzillai G., Walter Kidde & Company, Incorporated, 140 Cedar St., New 
York, N. Y. 

Yerxa, R. B., Taggart and Yerxa, 165 Division St., New Haven, Conn. 

Youngman, R. H., Harbison-Walker Refractories Company, Farmers Bank Bldg., 
Pittoburfl^, Pa. 

Zerban, F. W., Penick & Ford, Ltd., Incorporated, Marrero, La. 

Zimmerman, K C, Firestone Tire & Rubber Company, Akron, Ohio. 

Zimmerman, R. £., American Sheet and Tin Plate Company, 210 Semple St., Pitts- 
burgh, Pa. 

Zimmermann, F., Baker & Co., Inc., Newark, N. J. 

Zinsser, J. S., Zinsser & Ca, Hastings-on-Hudson, N. Y. 

Zobel, F. C, Ernst Zobel Company, Inc., 104 2nd Ave., Brooklyn, N. Y. 

Zurbrigg, D. Anton, The L. D. Caulk Company, Milford, Del. 



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Vol.3. Part 2 MARCH, 1922 Number 17 



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SaENTIFIC papers PRESENTED 

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BULLETIN 

OF THE 

NATIONAL RESEARCH COUNCIL 

Vcrf. 3, Part 2 MARCH, 1922 ' Number 17 



SCIENTIFIC PAPERS 

PRESENTED BEFORE THE AMERICAN GEOPHYSICAL 

UNION AT ITS SECOND ANNUAL MEETING 



CONTENTS 
Section of Geodesy 

Measurement of gravity at sea. A review. By Lyman J. Briggs 3 

Isostasy. By John F. Hayford 11 

The earth-tide experiment. By Henry G. Gale 16 

The Eotvos balance. By W. D. Lambert 17 

The problem of the earth tides. By W. D. Lambert 18 

Section of Meteorology 

Solar radiation and terrestrial phenomena. By C. G. Abbot 27 

Relations between solar activity and its various aspects, and the phenomena 

of terrestrial weather. By C. F. Marvin 31 

Daily meteorological charts of the world. By Edward H. Bowie 36 

World aerology. By Willis Ray Gregg 41 

World digest of meteorological data. By W. J. Humphreys 49 

General adoption of the centesimal system of angular measurement with 

application to anemometers and nephoscopes. By Alexander McAdie... 50 
Section of Terrestrial Magnetism and Electricity 

A sine galvanometer for determining in absolute measure the horizontal 

intensity of the earth's magnetic field. By S. J. Barnett 54 

Activity of the earth's magnetism in 1915. By D. L Hazard 55 

On measures of the earth's magnetic and electric activity and correlations 

with solar activity. By Louis A. Bauer 59 

The penetrating radiation and its bearing upon the earth's electric field. By 

W. F. G. Swann 65 

Recent results derived from the diurnal-variation observations of the 

atmospheric-electric potential-gradient on board the Carnegie. By 

S. J. Mauchly 73 

Section of Physical Oceanography 

Suggestions relative to the application of mathematical methods to certain 

basic problems in dynamic oceanography. By G. F. McEwen 78 

State of progress in continuous recording oceanographical instruments. By 

Albert L. Thuras 82 

1 



CONTENTS 

Present status of researches on marine sediments in the United States. By 
Thomas Wayland Vaughan 85 

The intervab that should obtain between deep-sea soundings to disclose the 
orography of the ocean basins. By G. W. Litdehales 90 

New methods of observing winds at flying levels over the ocean. By Alex- 
ander McAdie 94 

The steering line of hurricanes. By Alexander McAdie 102 



^ 



These papers were presented at the second annual meeting of the 
American Geophysical Union held at the National Research Council, 
Washington, D. C, April 18, 19 and 20, 1921. The names of three of 
the sections (seismology, volcanology and geophysical chemistry) do not 
appear in the table of contents, as these meetings were devoted to discus- 
sion and no scientific papers were presented. 

The American Geophysical Union is the Committee on Geophysics of 
the National Research Council and is the National Committee for the 
United States of the International Geodetic and Geophysical Union. 



MEASUREMENT OF GRAVITY AT SEA 

A Review 

r 

' By Lyman J. Buggs 

METHODS OF DETERMINING GRAVITY AT SEA 

The measurement of the acceleration of gravity over the oceans is a 
matter of interest to the geodesist in the determination of the figure of th<^ 
geoid and in investigations relating to isostatic compensation. For the 
requirements of these problems it is desirable that the probable error of 
the gravity determinations should not exceed one part in 50,000. At first 
sight this accuracy does not seem to be unattainable, particularly to those 
who are familiar with the remarkable work that has been done with inva- 
riable pendulums on land stations, where the probable error has been 
reduced to. two or three parts in a million. But when we consider that in 
measurements at sea the vertical acceleration of the ship is imposed upon 
the gravitational acceleration which we are trying to measure, the difficulty 
of the problem becomes apparent. For example, in the case of a ship 
which rises and falls through a height of a meter during a period of 10 
seconds, the average vertical acceleration without regard to sign is about 
0.004g, or 200 times the permissible probable error of the measurement. 
Such vertical accelerations of the ship are not uncommon, although the 
sea is sometimes so smooth that an index point may be set in grazing 
contact with the surface of a mercury column with almost laboratory 
precisioiL 

The oscillations of the sensitive element due to the vertical accelerations 
of the ship may be controlled by damping, but it is doubtful whether the 
damped system gives the same result as when vertical accelerations are 
absent. This question cannot be answered from observations at sea, and 
necessitates laboratory methods of testing gravity apparatus which will 
be referred to later. 

Virtually all the methods that have actually been used for gravity deter- 
minations at sea involve and depend upon observations of the length of a 
mercurial column supported by gas pressure. The pressure p of the gas 
may be equated to p g h where p and h refer to the density and height of 
the mercury column. Knowing p, p and h, the acceleration of gravity g 
can at once be evaluated. The various methods differ in the manner in 
which p and h are determined. 

Siemens' method: The first actual measurements of the variation of 
gravity at sea appear to have been made by Sir Wm. Siemens* in 1875. 
He believed that at sea the value of g was diminished by an amount very 
nearly proportional to the depth of the ocean, and his primary purpose 

^C. Wm. Siemens. On determining the depth of the sea without the use of a 
sounding line. PM, Trans,, 167, 1877, 671-692. 

3 



4 GEODESY 

was to develop a sounding apparatus on this principle as an aid to navi- 
gation. 

His first instrument consisted of a barometer with a large sealed-off 
air chamber to eliminate the effect of variations in atmospheric pressure 
(fig. 1). The barometric column included three liquids — mercury, diluted 
alcohol and juniper oil. The vertical column was expanded into a bulb 
b, at the level where the mercury and alcohol surfaces were in contact, 
with a second evacuated bulb d at the top, which contained the free 
juniper-oil surface. The readings were made on the position of the 
'alcohol-oil surface c in the constricted tube joining the two bulbs. With 
this device the scale deflection for a given change in g was 300 times that 
of a simple mercurial column. 

This instrument proved unsatisfactory and was abandoned in favor of 
a second "bathometer," which consisted of a steel spring balance of a 
peculiar type. A vertical steel tube was fitted with reservoirs at top and 
bottom, the floor of the lower reservoir consisting of a thin corrugated 
steel diaphragm. This system contained mercury, the free surface of the 
mercury being in the upper reservoir, which during measurements was 
open to the atmosphere. The load on the diaphragm was carried by two 
long steel spiral springs connected to a yoke beneath the diaphragm and 
suspended from the upper reservoir. The mercury constituted the load 
on the balance and at the same time served to damp the oscillations 
through the action of a constriction in the tube just below the upper 
reservoir. The change in the load due to a change in g resulted in a 
vertical displacement of the yoke and was measured by means of a mi- 
crometer screw supported from the lower reservoir. The observations 
required corrections for temperature and atmospheric buoyancy. The 
instrument was not checked by testing it at two land stations where the 
relative value of g was accurately known. His results show, however, 
a remarkable correlation with the depth as obtained by direct soundings, 
which were made immediately after the bathometer readings. In a series 
of about 30 observations involving depths up to about 2,500 fathoms, the 
discrepancy was seldom more than 10 per cent. No corrections were 
applied for variation in latitude, which ranged from 45* to 49* N. 

Hecker's fnethod: The appearance of Helmert's equation for the varia- 
tion of g with latitude, based on land stations, led Hecker^ to undertake 
the task of providing data to test its validity for sea stations as well. In 
1901 he began an extended series of gravity measurements at sea which 
eventually included systematic observations in the Atlantic, Pacific and 
Indian oceans and in the Black Sea. 

In using a barometric column for measuring g, two procedures are 
available : ( 1 ) the air chamber at the base of the column may be sealed, 

^ For a description of the apparatus empioyed by Hecker and a summary of hit 
ocean measurements, see Hecker, C, Bestimmune der Schwerkraft auf dem 
Schwarzen Meere und, an dessen Kiiste sowie neue Ausgleichung der Schwerkraft- 
messungen auf dem Atlantischen, Indischen, und Groszen Ozean, Zentralbur. Inter- 
not. Erdmessung^, Veroiientlichungen Berlin, N. F., Nr. 20 (1910). 



b nkf 



t 



Fic.1. Sfcroen.* F«g. 2. DuffieWs 

first apparatus. apparatus. 



^. 



Fic 3. Briggs' apparatus. 



6 GEODESY 

as in Siemens' first instrument, in which event we eliminate variations in 
pressure due to atmospheric changes, but are left with an instrument 
which is very sensitive to temperature changes, as it becomes in effect a 
gas thermometer; or (2) we may leave the air-chamber open to the 
atmosphere ; in this case the temperature effects are greatly reduced, but 
it is necessary to measure the air-pressure p by some independent means. 

Hecker in his pioneer investigations chose the latter procedure and 
determined the pressure from boiling-point measurements of water re- 
ferred to vapor-pressure tables. The vapor-pressure of water increases 
very rapidly with temperature in the neighborhood of the boiling-point, — 
approximately one twenty-eighth of an atmosphere per degree. There- 
fore, in order to determine the pressure to 1 part in 50,000 it is necessary 
to know the temperature interval from freezing-point to boiling-point with 
an error not greater than 0^.0006 C. 

Hecker used mercury thermometers in his boiling-point determinations. 
He had no means of checking the fundamental intervals of these ther- 
mometers at sea, for this determination depends upon accurate barometric 
pressure measurements which can be obtained only at land stations where 
the value of g is known. Consequently any departure of the fundamental 
interval from that determined at land stations enters directly into the 
boiling-point determinations at sea as a systematic error. Furthermore, 
the best of mercurial thermometers exhibit variations in the fundamental 
interval. For example, Waidner and Dickinson^ found that the funda- 
mental interval of the primary mercurial standards of the Bureau of 
Standards varied through a range of 0^.015 C. during a ten-day period, 
which would correspond to a variation of more than one part in 2,000 
in the value of g. The probable error of the fundamental interval deter- 
minations in Waidner and Dickinson's measurements under favorable 
laboratory conditions was dbO^'.OOS C, which may be taken as a measure 
of the maximum refinement obtainable in barometer-hypsometer measure- 
ments aboard ship ; and this corresponds to a probable error in the value 
of g of more than one part in 10,000. 

If hypsometer determinations are to be made, resistance thermometry 
would be preferable to mercurial thermometry, since the resistance ther- 
mometer is more sensitive and shows less variation from day to day in 
the fundamental interval. The steam point of a resistance thermometer 
can be readily determined under laboratory conditions to 0^.002 C, but 
whether this accuracy could be obtained on board ship with the galvano- 
meter on an unstable base is questionable. 

In my opinion, the barometer-hypsometer method is not the most prom- 
ising way of attacking the problem of measuring g at sea, because (1) the 
method involves two operations; (2) the temperature errors in hypsome- 
try lead to errors in the derived value of g which are ten times as great 
as those produced by equal temperature errors in a closed system; and 
(3) the motion of the ship relative to the air produces a change in baro- 

^Bull Bur. Standards, 266^, Washington, D. C (1907). 



GEODESY 7 

metric pressure below deck. If this relative motion is unsteady from any 
cause, as for example variable winds, errors may result unless the barom- 
eter and hypsometer are read simultaneously. Dufiield (1921) on board 
a destroyer observed pressure effects of this kind as large as one millibar. 

The use of a sensitive aneroid barometer has been proposed as a substi- 
tute for hypsometric measurements, but here again a double operation is 
involved. If a spring system could be devised which would be sufficiently 
sensitive and reliable to measure pressure to the required degree of accu- 
racy, it would be better to employ it directly as a force balance to measure 
the change in g than to equate the observed pressure to the observed 
length of a mercury column, for the double operation serves only to 
increase the probable error of the final result. 

Duffield's method: Duffield^ in 1914 employed the apparatus shown in 
figure 2 in some preliminary measurements of g during a voyage from 
Australia to England. The apparatus, which is of the sealed gas-chamber 
type, possesses a unique and valuable temperature-compensation feature. 
A constant volume of air is maintained in the bulb B by keeping the 
mercury always up to the electrical contact at C. The air in the bulb B 
is under reduced pressure in order to reduce the length of the apparatus. 
The barometer tube is bent so that H is vertically above C, the length of 
the column HC being approximately 20 centimeters. The mercury level is 
kept at C by raising or lowering the mercury in the index tube D. This 
operation is effected by slowly exhausting or admitting air through F as 
required. The index tube D is of fine bore and the value of g is calculated 
from readings upon the level of the mercury in this tube when contact is 
made with the pointer at C. The side tube E is used only for the purpose 
of making initial adjustments, and to permit the apparatus to be used for 
various ranges of temperature. 

The reservoir of mercury R is introduced for the purpose of tempera- 
ture compensation and when the dimensions of the apparatus are suitably 
chosen the increased pressure of air in the bulb B due to a given rise of 
temperature is automatically counterbalanced by the rise of the level H, 
occasioned by the expulsion of mercury from the reservoir. The com- 
pensation is perfect at only one temperature, but for small departures 
the error is small. At sea the apparatus was immersed in a water bath 
which was hung by cords from the ceiling of the refrigerator room of the 
ship, and readings on the index tube were taken through a window in 
the side. 

Duffield's apparatus as reconstructed in Australia was over compen- 
sated, an increase in temperature of 1** C. necessitating the removal of a 
thread of mercury 60 mm. long. In other words, a temperature change 
of this amount resulted in a change in the reading of the index scale 
corresponding to the computed change in g in going from the equator to 
54® N. Lat. Trouble was also experienced from a break in the capillary 



* W. G. Diiffield. Apparatus for the determination of gravity at sea. Proc, Roy. 
Soc. Land, (A), 112, 1916, 505-517. 



8 GEODESY 

mercurial column in the barometer tube. Owing to these difficulties actual 
observations were limited to a series of 25 preliminary measurements in 
the Indian Ocean from Lat. 0° to 16** N. These results show an average 
deviation with regard to sign of H-O-Ol cm./sec* from values computed 
from Helmert's equation; in other words, a chance distribution of the 
observations about the line representing Helmert's computed values is 
indicated. The average deviation of the observations without regard to 
sign is 0.14 cm./sec*. The anomalies are, however, not known. If we 
assume that there are no anomalies, this corresponds to an average error 
of 1.4x10""^. It is interesting to note in this connection that Schuster 
computes from the dimensions of Duffield's apparatus a maximum error 
due to pumping of about 3.6X 10~< for vertical motions of the ship of one 
meter amplitude. 

In a recent article Duffield^ has given a brief description of tests made 
with apparatus other than his own during his voyage to Australia in 1914. 
This included instruments of the sealed-cistern barometer type constructed 
by Prof. Hecker and an aneroid barometer supplied by Sir Horace Dar> 
win. No quantitative results are given. 

Schuster* has contributed a valuable analysis of the effects of forced 
vibrations which may be imposed on the mercury in gravity apparatus by 
the vertical acceleration of the ship. This includes a discussion of ( 1 ) a 
single constricted barometer tube, (2) the oscillations in a complex inter- 
connected system of three tubes as in Duffield's apparatus, and (3) the 
experimental errors in the latter apparatus as affected by the relative 
dimensions of the various parts. He emphasizes the importance of the 
condition that the flow of mercury in the barometer tube and contact tube 
be such that the difference in level is always that of hydrostatic equi- 
librium. This condition is fulfilled if the cross-sections of the capillaries 
are equal and the lengths of the capillaries are inversely as the reduced' 
cross-sections of the tubes at the free surfaces of the mercury. 

Briggs' method: Briggs* employed apparatus similar to that shown 
diagramatically in figure 3 for gravity observations during a voyage from 
Sydney to San Francisco in 1914 and again from New York to San Fran- 
cisco via Panama in 1915. This apparatus is of the closed-barometer 



• The investigation of gravity at sea. Nature, 106, 1921, 732-734. 

"Arthur Schuster. On the determination of gravity at sea (Note on Dr. Duffield's 
paper). Proc, Roy. Soc. Lond. (A) 112, 1916, 517-528. 

• The reduced cross-section a represents the actual cross-section a corrected for 
the effect of the pressure and volume of the air above the surface of the mercury. 
Let 

^=:the original volume of air. 
P=thc original air pressure. 
A=the height of the mercury column equivalent to P, 

Then — -« h it 

Qi a V 

• L. J. Briggs. A new method of measuring the acceleration of gravity at sea. 
Proc. Nat, Acad, Set. 2, 1916, 399-407. 



GEODESY 9 

type. The mercurial column is contained in the capillary c (bore 0.6-0.7 
mm.), the lower end of which opens beneath mercury in the bottom 
of the gas chamber d. This capillary is sealed to the wall of the gas- 
chamber where it passes through the upper end. The upper part of the 
capillary is bent into a flexible zigzag and ends in the spherical bulb h 
((tiameter 2 cm.). The bulb contains a fixed iron point p sealed to the 
inside of the bulb by means of an inserted platinum wire and extending 
vertically downward, so that the point is approximately at the center of 
the bulb. The length of the mercurial colunm is about 74 cm. 

The flexible capillary permits a slight vertical movement of the observ- 
ing bulb with respect to the gas chamber. This movement is determined 
by a micrometer screw of 1 mm. pitch which controls the motion of a 
carriage in which the observing bulb is rigidly mounted. The carriage 
slides on parallel rods mounted on a base which is rigidly cemented to 
the neck n of the gas chamber, so that the position of the bulb relative 
to the gas chamber is definitely determined by the screw. 

The apparatus is protected by a close-fitting metallic jacket, and is kept 
at a constant temperature in a bath of melting ice. It is necessary to 
determine only the position of the upper end of the barometric column. 
The design of the instrument is such that in setting the index in contact 
with the- mercury surface the enclosed gas is automatically reduced to a 
constant volume ; and since the temperature is constant, all measurements 
are made at constant pressure. The relative value of g at two stations 
is thus inversely proportional to the observed length of the column at 
these stations. 

The contact of the index point with the mercury surface can be deter- 
mined either electrically or by direct observation. Both methods were 
used. In the latter case the fixed point was observed through a glass tube 
introduced through the ice, the tube containing a low-power lens. The 
point was illuminated through a similar tube on the opposite side. If the 
sea was so rough as to cause pumping of the column, the point was so 
adjusted that it was in contact half the time as nearly as possible. Since 
the motion of the ship is not strictly periodic, there is considerable uncer- 
tainty connected with such settings. 

This instrument possesses the following features which experience has 
shown are desirable in gravity apparatus: (1) The glass part of the appa- 
ratus is hermetically sealed and can be made really gas-tight. There are 
no stop-cocks, ground joints, or mercury seals. (2) It is necessary to 
make settings only at the upper end of the barometric column. (3) This 
permits the complete immersion of the apparatus in an ice-bath, which is 
the most dependable source of constant temperature for use on shipboard. 
(4) The apparatus is portable, since at room temperatures the pressure 
is sufiident to fill the observing bulb with mercury. 

Gravity determinations which were made in 1914 on board ship in 
Wellington harbor and Sydney harbor using observations in San Francisco 
harbor as a base station, and in 1915 in San Francisco harbor using New 



10 GEODESY 

York harbor as a base, show an average departure from pendulum obser- 
vations of about one part in 50,000. These observations were made under 
favorable conditions and serve to show the degree of accuracy with which 
the instruments held their adjustments during the long voyages rather 
than to provide any indications of the accuracy of the sea observations. 
In fact, the publication of the sea measurements, which show some rather 
large anomalies, has been withheld in the hope that apparatus similar to 
that described in the last section of this paper might be available to deter- 
mine the errors of the instruments under oscillations approximating sea 
conditions. 

CORRECTIONS FOR THE COURSE AND SPEED OF THE SHIP 

Eotvos* has shown the necessity of applying a correction for the east- 
erly or westerly motion of the ship, due to the fact that the ship's motion 
modifies the angular velocity of the apparatus about the earth's axis. The 
centrifugal force acting on the mercurial column when on board a ship 
moving east or west is therefore not the same as when the ship is at rest 
or moving north or south. The correction may be as great as 1 part in 
10,000, but can be accurately computed if the course, speed, and approxi- 
mate latitude of the ship are known. Dufiield (1921) observed a change 
equivalent to 0.1 millibar when the course was altered from east to west 
when steaming at 22 knots, which corresponds to an apparent change of 
1 part in 10,000 in g. He does not state where his experiments were 
made. For Lat 55**, which represents approximately the mean latitude 
of the North Sea, the computed change is about 0.19 cm./sec.*, or 2 parts 
in 10,000 in the value of g. 

LABORATORY TESTING OF GRAVITY APPARATUS 

There seems to be no practical way of determining the accuracy of 
gravity measurements directly from sea observations. With a ship at 
one's command, repeated traverses could be made of the same sea station 
under varying sea and weather conditions ; but while this would provide 
a measure of the accidental errors, it would tell us nothing regarding 
systematic errors, for the exact value of g at the station would not be 
known. The value of ^ in a long, narrow bay could be closely approxi- 
mated from pendulum observations on both shores. To satisfy other 
requirements the bay would have to be sufficiently open and windswept 
to represent the conditions prevailing in a moderate sea. Such a test 
seems precluded without the enlistment of government aid. 

We can, however, simulate sea conditions at a land station where g is 
accurately known and I wish to emphasize the importance of sudi tests 
for all gravity apparatus. Suppose we construct a platform capable of 
independent reciprocating horizontal translations in two directions at right 
angles, corresponding in period to the roll and pitch of the ship. Let us 
mount upon this platform a second one arranged for vertical oscillations, 



* Sec Hclmert, loc. cit. 



GEODESY 11 

large enough to carry the apparatus and the observer. All the recipro- 
cating motions are to be capable of a continuous change in amplitude if 
desired in order to secure the conditions which arise when the period of 
the ship differs from that impressed by the waves. We have omitted 
the motions corresponding to the angular motions of the deck, for struc- 
tural reasons ; for these angular motions would only increase the rotation 
of the apparatus in its gimbals, and there will always be sufficient move- 
ment of the gimbals arising from the horizontal accelerations to simulate 
disturbances due to friction. With this apparatus it will be possible to 
investigate the effects of horizontal and vertical accelerations, singly and 
combined, under conditions where g is accurately known and thus obtain 
a measure of the accidental and systematic errors of the method. Inde- 
pendent rolling and pitching oscillations are probably not required for 
gravity apparatus, but the equipment proposed has other useful applica- 
tions, as for example in testing gyroscopic compasses and gyroscopic 
stabilizers, in which both rolling and pitching accelerations should be 
included. Plans for such an equipment are now being prepared, and it 
is hoped that arrangements can soon be made for its construction and 
installation at the Bureau of Standards, where it will be available for 
testing all gravity apparatus. 

Bureau of Standards, 

Washington, D. C. 

ISOSTASY 
By John F. Hayfobd 

I assume that I am expected to bring forward whatever ideas will, in my 
opinion, help most at the present time in the development of a study of 
isostasy by stimulating further thinking along that line. From among 
the many topics which might be treated, I am selecting three : 

(1) I shall make some remarks on the recent paper entitled "The 
Chemistry of the Earth's Crust," by H. S. Washington. 

(2) I shall try to emphasize the desirability of an intensive study of 
two small areas by observations of gravity and deflections of the vertical. 

(3) I shall offer some considerations that lead me to believe that the 
undertow involved in isostatic readjustment is above, rather than below, 
the depth of compensation. 

CHEMISTRY OF THE EARTH'S CRUST 

Dr. Washington, in his paper entitled "The Chemistry of the Earth's 
Crust," * has set forth a piece of research of much importance to those 
who are studying isostasy. He has set forth the evidence derived from 
studies of the densities of igneous rocks. These densities are determined 
from chemical analyses. In the latter part of the paper he sets forth the 
correlation which is observable between the density of igneous rocks, on 

' Journal of the Franklin Institute, 190, December, 1920, 757-815. 



12 GEODESY 

the one hand, and, on the other hand, the elevation of that part of the 
earth's surface under which the rocks lie. 

The evidence given in the paper seems to be conclusive in its general 
features on three points, namely : 

(1) That igneous rocks under the oceans are denser than those under 
the continents ; 

(2) That igneous rocks under the various continents are less dense 
the greater the mean elevation of the continent ; and 

(3) That igneous rocks under different parts of any one continent are 
less dense the higher is that part of the continent. 

All three of these conclusions are in accord with the theory of isostasy 
and, in Dr. Washington's words, constitute "almost a conclusive proof of 
the general validity of the theory of isostasy." 

Dr. Washington seems to interpret the relations pointed out as being 
due to original, or early, segregation of the material. I do not question 
this interpretation so far as ( 1 ) is concerned. The relative positions of 
the oceans and continents are permanent or semi-permanent. It may well 
be that the oceans are now in their present position because material of 
such a nature as to form dense rocks was placed early in the positions 
now occupied by the oceans. 

The same interpretation may, however, be questioned, in part, in so far 
as (2) and (3) are concerned. Are the differences in densities between 
the different continents referred to in (2) and between different parts of 
any one continent referred to in (3) due to original or early segregation? 
Or are these differences due, in part at least, to some response of the 
material to a change of pressure in such a manner as to bring about a 
change of density ? The continents probably have not had the same rela- 
tive elevations throughout geologic time as they now have. Certainly, 
the different parts of any one continent have not, in general, the relative 
elevations now that they had at various times during the geologic history 
of the continents. For example, the Appalachian region, referred to by 
Dr. Washington, in the eastern part of the United States, is now much 
lower than Utah, Colorado, and Nevada, and the density of the material, 
as measured by him, is considerably greater under the Appalachian region 
than under the states named. There was, however, a time during the 
geologic history of the North American continent when the Utah- 
Colorado-Nevada region was much lower than the Appalachian region was 
at that time. Have the relative densities in the two regions changed 
between that period and the present? 

This comment on Dr. Washington's paper is not intended at all as a 
criticism ; it is intended to supplement the paper and to stimulate further 
thought based on it. All who are interested in isostasy should be very 
keen to follow the further develpoments along the line indicated by Dr. 
Washington's paper. I understand that he, himself, will develop the evi- 
dence much more fully. The more complete evidence should be examined 
very carefully, with a view to determining the bearing of this evidence on 



GEODBSY 13 

any theories which may be held in regard to isostasy and the isostatic 
readjustment. 

PROPOSED INTENSIVE STUDY OF SMALL AREAS 

We shall take a short time to consider the possible benefits which would 
follow from an intensive study of two small areas, let us say about 100 
miles square, one on rather flat country, such as Louisiana, and another 
in hilly or mountainous country. The intensive study would be based on 
closely spaced stations of two kinds, stations at which deflections of the 
vertical are determined and gravity stations. Let us suppose that obser- 
vations of these two kinds were made in each of two such areas and then 
that, by the proper office methods and by the combination of the two kinds 
of observations, the distribution of the densities beneath each of the two 
areas was determined with as great accuracy as is possible. What benefits 
would follow from two such studies? Briefly, I believe that the benefits 
would be as indicated in the four paragraphs which follow : 

1. The studies would bring out the actual advantages and limitations 
of this line of attack on the problem of determining the distribution of 
densities beneath the earth's surface. The relative strength or weakness 
of this line of attack, as compared with the usual line of attack, is not 
now well known. The usual line of attack is to use deflections of the 
vertical stations or gravity stations which are widely distributed somewhat 
uniformly over a very large area. 

2. The studies would probably furnish a considerable amount of evi- 
dence on the point which has been ably brought out by Dr. William Bowie 
that the small anomalies in gravity and in deflections of the vertical which 
remain after correcting for topography and isostatic compensation are 
closely related in many regions, if not as a rule, to the surface geology 
of those regions. It is important that the extent to which this is true 
should be determined. There seems to be no doubt that it is true, in a 
general way, for large areas. The question is, to what extent is it true for 
small areas? 

3. The studies would give valuable indirect evidence as to the extent 
to which the present conclusions from the evidence now available are 
vitiated by local effects which* are at present unavoidably assumed, for 
want of more exact information, to extend half way to the next station, 
so to speak. 

4. The two intensive studies would help to determine whether oil and 
salt may be located by geodetic measurements. This suggestion has been 
made at various times by Dr. David White, Chief Geologist of the U. S. 
Geological Survey. It is important to know whether gravity stations and 
deflections of the vertical may be used as a divining rod for that purpose 
with sufficient accuracy. If the accuracy of such a divining rod is so low 
that its indications are likely to be misleading, then it is not feasible to 
try to use the observations in this way. On the other hand, if two such 
intensive studies as are indicated here show that sufficient accuracy is 



14 GEODESY 

possible, then certainly the method should be used, in combination possibly 
with other methods. The two intensive studies might possibly be made 
in regions in which salt or oil are believed to exist, or are known to exist, 
in large quantities. 

The suggestion that one study should be in rather fiat country and the 
other in rather hilly country is based on two considerations. In very flat 
country the conclusions reached will be vitiated to a much smaller extent 
by an error in the assumed surface density of the material than in rough 
country. On the other hand, in hilly or mountainous country the depth 
at which any material of abnormal density lies may be determined with 
greater accuracy than in flat country, 

DEPTH OF UNDERTOW 

Let us now turn to the question, is the undertow involved in isostatic 
readjustment above or below the depth of compensation? 

Assume that, at some time in the remote geologic past, the North Amer- 
ican continent and its various major parts have been almost completely 
compensated in the isostatic sense. Assume that, in later geologic past 
time and up to the present time, there have been large amounts of erosion 
from large portions of the continent and corresponding large amounts of 
deposition in other parts. Assume that in that period and up to the 
present, readjustment toward isostatic conditions has been in progress by 
horizontal transfer of material from beneath the regions of deposition 
towards the regions of erosion. 

It is reasonably certain that, on the whole, these three assumptions are 
true. The question on which it is desired to concentrate attention is, has 
the horizontal transfer taken place below or above the depth of com- 
pensation? 

It is important to secure the correct conclusion on this point, whatever 
it is, because the apparent correlation of geodetic and geologic evidence, 
or the apparent contradictions between two lines of evidence, probably 
depend somewhat intimately upon the conclusion reached. I believe that 
the horizontal transfer has taken place above the depth of compensation, 
say within 100 kilometers of the surface, rather than below that depth. 
I propose to state, very briefly, some of the lines of thought that have led 
me to that conclusion. 

If it is assumed that, under an area of deposition, the material down 
to the depth of compensation all sinks under the added load and that the 
horizontal transfer of material occurs below that depth, the case is similar 
to that of an ice floe. Under each elevation on the upper surface, in this 
case, there must develop a much larger bump on the lower surface of the 
floating mass. The conception is that of a crust floating on a relatively 
plastic stratum. The level of compensation, in this case, is at the lower 
side of the floating crust. As in this case there must be extensions of 
the crust downward, below the mountains, the depth of compensation will 
be variable, being great under high areas and small under low areas. The 



GEODESY 15 

geodetic evidence, as far as I have been able to examine it, does not seem 
to be conclusive that there is any such relation between the depth of com- 
pensation and the elevation of the surface. This leads me to be skeptical 
of such theory, which involves a horizontal flow limited mainly to those 
portions of the earth that are below the depth of compensation. 

In general, I am skeptical of any explanations of isostatic readjustment, 
or of other phenomena in the earth, which involve a relatively plastic 
stratum in contrast to more rigid material above. In each of the cases 
in which I have been able to follow the mechanics of the problem to itiy 
own satisfaction, I have not been convinced that the resort to the device of 
introducing a plastic layer into the concept is necessary. So, in the prob- 
lem now under consideration, which is that of the isostatic readjustment, 
I do not find it necessary to assume any stratum to be more plastic than 
the one above, in order to harmonize the observed facts of various kinds. 

There is abundant geological evidence of horizontal stresses and strains 
in the earth's crust. This evidence seems to me to be conclusive. The 
geologic evidence seems to me to indicate a horizontal transfer of material 
during isostatic readjustment relatively near the surface, rather than at 
great depths. If the horizontal transfer involved in the undertow were 
in a plastic stratum more than 100 kilometers below the surface, certainly 
the horizontal stresses set up in the surface material would be much less 
than if the same transfer occurred in less plastic material nearer the 
surface. 

In attempting to determine the mechanics of the isostatic readjustment 
which apparently takes place when great loads are removed from a region 
of erosion and equally great loads are added to other regions as deposited 
material, it is extremely important to keep in mind that material deforms 
under relatively small differences in the two principal stresses. A very 
large increase in both the principal stresses is necessary in order to pro- 
duce deformation if the increases are equal. In an elementary cube of 
the material, let p^ be the pressure on the upper and lower faces of the 
cube. Let p^ be the pressure on theside faces of the cube. If pt=pi, 
the material is under isostatic conditions. Under these conditions both 
^3 and Pi may be increased very largely before appreciable compression is 
produced in such material as constitutes the earth's crust. On the other 
hand, if p^ is increased without changing p^, then deformation of the cube 
will be produced for a relatively small difference ^j — Pu corresponding 
to an added load of a few thousand feet only of materisil. The cube will 
be deformed in the sense in which the vertical dimension is decreased 
and the horizontal dimensions increased. Consider the movements which 
will take place if the many elementary cubes under a large loaded area are 
so distorted. Evidently the motions of the material under the margins 
of such a load will have a horizontal component. This line of thought, 
followed through to its logical conclusions, and made more definite by 
careful analysis, will indicate that the horizontal transfer of material 
occurs largely at moderate depths, certainly at less than 100 kilometers 
as a rule. 



16 GEODESY 

I am perfectly aware^that the presentation of the considerations set 
forth in the last few paragraphs has been too brief for clearness or con- 
clusiveness. The paragraphs have been written as suggestions rather 
than as demonstrations. They indicate lines of thought which should be 
followed up carefully if one wishes to reach true conclusions. 

I desire to reiterate my opinion/ based on such thought as I have been 
able to give to the subject, that the undertow involved in isostatic re- 
adjustment is above the depth of compensation. 

THE EARTH-TIDE EXPERIMENT 
By Henry G. Gale 

I understood Professor Hayford to say that he did not believe that a 
fluid layer exists beneath the solid crust of the earth. The same conclu- 
sion may be drawn from the earth tide experiment which was conducted 
on the grounds of Yerkes Observatory by Professor Michelson and my- 
self. It seems pretty certain that the earth tides are the same as they 
would be if the earth were a highly elastic homogeneous solid, both with 
respect to the phase and amplitude of the earth tides. 

The experiment was entirely successful from a physicist's standpoint. 
The interferometers gave very little trouble. One of them did not require 
readjustment during the entire year. Two were readjusted to change the 
width of the fringes, and on one interferometer it was necessary to re- 
silver one of the mirrors. As a source of light we used commercial alter- 
nating Cooper-Hewitt lamps, and they proved to be entirely satisfactory. 
The only serious interruptions were caused by breaks in the electric service 
due to storms, and occasional short shut-downs by the electric light com- 
pany which supplied the current. The experiment at Yerkes Observatory 
was continued for just one year. This is probably long enough to give 
values of the semi-diurnal and diurnal tides, accurate to a few tenths of 
one percent. For tides of longer period the experiment should be con- 
tinued for, say, five years, although possibly three years would be long 
enough. 

The experiment is now being repeated on the grounds of the California 
Institute of Technology at Pasadena, California. One additional station 
should be installed, preferably on an island in the Pacific, far from the 
continental borders. If the three stations should give results in agreement 
on both the phase and amplitude of the earth tides, I should feel that the 
problem had been solved. If the three were not in agreement, at least 
one-half dozen additional stations would be desirable. They should be 
well scattered in latitude, and with reference to tidal coasts. 

The cost of installing a station is not excessive, and one man can easily 
keep a station in operation and reduce the observations. It would proba- 
bly be worth while to look for a correlation between the slight changes of 

^ As early as 1911 I had reached the above conclusion, as indicated by one of the 
diagrams in an article published in Science, 23, No. 841, 199-206, Feb. 10, 1911. 
entitled "The relations of isostasy to geodesy, geophysics and geology." 



GEODESY 17 

level often shown by the apparatus and the approach or passage of the 
intense barometric lows and highs of large area. It would certainly be 
worth while to install a specially designed apparatus, similar to that used 
for the earth tides, to detect and measure the rate of tilting in the surface 
layers of the earth's strata at especially favorable places. A relation be- 
tween such rates of tiltii^ and earthquakes might be detected. 

THE EOTVOS BALANCE 
By W. ST. Lambkkt 

There is one instrument of use in the study of terrestrial gravity which 
has not yet been employed in the western hemisphere, though it has to a 
limited extent in Europe. This instrument is the Eotvos balance. It 
should be tried, I believe, in making the proposed minute investigation of 
gravity in a level region of limited extent.* To judge by accounts of work 
done with the balance in Europe it would certainly supplement the pendu- 
lum advantageously in the proposed gravity survey and might largely 
supersede it. This does not by any means signify, however, that the 
balance is always and everywhere a substitute for the pendulum. This 
is not the occasion for an exposition of the principles' of the instrument, 
but it may be said that the Eotvos balance connects the results at adjacent 
points in a limited region with one another in a way that the pendulum 
cannot well do. 

In Europe they evidently believe in its possibilities as an indicator of 
the existence and location of concealed irregularities and discontinuities in 
density. Some of these discontinuities may mean strata of geological or 
commercial interest. At least three attempts have been or are being made 
to locate such strata by the use of the balance ( 1 ) by Dr. Schumann to 
locate lignite deposits in Austria,' (2) by Professor Schweydar for geo- 
logical purposes in the region about Hamburg, Germany,' and (3) an 
attempt to locate salt deposits in Poland.^ It will be of interest to know 
how successful these attempts prove to be. 

The Eotvos balance determines certain second derivatives of the gravity 
potential function. It does not, however, determine the second derivative 
in the vertical direction. This quantity has to be determined theoretiqilly. 
This is the most serious deficiency of the instrument and explains why it 
is of comparatively little use in rough country. Attempts are being made 
by Berroth, Helmert's assistant, in his last researches on gravity, to devise 
a means of determining experimentally the second derivative in the verti- 
cal direction.' 



' See p. 13 of this bulletin. 

'Akademie der Wissenschaften m IVien: math. phys. Klasse. Sttzung vom 8 
Jaimer, 1920. Reported in the Akademische Anseiger. Nr. 1. 

' '*Rapport sur les Travaux du Bureau Central de 1 Association Geodesique Inter- 
nationale en 1920,** p. 4. 

* 1 have seen nothing in print about this third attempt I have word of it person- 
ally from the man proposing to make the observations. [Added in proof: This 
attempt has not yet been made on account of the lack of instrument] 

' Same reference as in second preceding footnote. 



18 GEODESY 

THE PROBLEM OF THE EARTH TIDES 

By W. D. Lambekt 

There are two methods of attacking the problem of the elastic proper- 
ties of the earth, ( 1 ) the study of the seismological evidence, on which I 
shall not touch at all, and (2) the study of earth tides. Even after the 
best available observational evidence from the earth tides has been ob- 
tained, a good deal of h3rpothesis and interpretation is required before we 
can say : "The elastic constants of the earth are thus and so." It is not, 
however, of this that I wish to speak, but rather of the problem of obtain- 
ing the true values of the earth tides. This subject is connected with 
several other geophysical questions and this paper, therefore, falls natu- 
rally into three divisions: (1) Earth tides and the long-period oceanic 
tides; (2) earth tides and the short-period oceanic tides; (3) earth tides 
and the variation of latitude. 

EARTH TIDES AND THE LONG-PERIOD OCEANIC TIDES 

The first quantitative evaluation of the earth tides and hence of the 
elastic properties of the earth came from a discussion of the so-called 
long-period oceanic tides. The suggestion which initiated the work ap- 
pears to have come from Lord Kelvin and the method and results are 
given in Thomson and Tait's "Natural Philosophy,"* but the actual dis- 
cussion of the observations was made by Darwin.^ 

The discussion is based on the assumption that the long-period oceanic 
tides for an ocean on a perfectly rigid globe may be calculated on the 
equilibrium theory. This means that it is assumed that the disturbance 
of equilibrium caused by the tide-producing forces of long period can 
travel so rapidly through the water and the forces themselves change so 
slowly that the ocean has time to adjust itself to the forces and that at 
any given instant the surface of the ocean forms an equipotential surface 
for the instantaneous field of force.* The observed oceanic tide would 
be the difference between the oceanic tide for a rigid body and the earth 
tide, and when the first two are known the earth tide may be inferred. 
From 33 years of observation on both the monthly and the fortnightly 
tides at 14 different ports Darwin deduced that the observed tides were 
about two-thirds as large as they would be on a perfectly rigid globe. The 
earth tide corresponding to the other third implies an effective rigidity of 
the earth about equal to that of steel.* Later methods of attacking the 



'Second Edition (1883), | 848. 

*G. H. Darwin: Scientific Papers," I, 340. This contains a reproduction of the 
passage in Thomson and Tait with some changes of notation and unimportant 
omissions. 

'This assumption is very evidently incorrect as re^rds the diurnal and semi- 
diurnal tides. It was supposed to be at least approximately true for the monthb^ 
and fortnightly tides. 

*The tides at Indian ports, which are more consistent with one another than the 
others, gave a much higher rigidity. 



GEODESY 19 

problem have given results somewhat similar, though in general tending 
towards somewhat higher values of the rigidity. 

Only a few years passed before this result was questioned because of 
its dependence on the equilibrium theory, and Darwin himself, apparently, 
was the first to question it.^ In treating the problem of tides on a globe 
covered with water — ^a problem first formulated by Laplace — ^he discov- 
ered solutions which for depths anything like these of our actual oceans 
gave tidal oscillations of perhaps half the amount deduced from the equi- 
librium theory. He concludes his article by saying: '*Thus it does not 
seem likely that it will ever be possible to evaluate the effective rigidity 
of the earth by means of tidal observation.'^ The mathematical treatment 
of the problem has since been developed by Hough* and Goldsborough." 
The latter has extended the treatment to include basins bounded by two 
parallels of latitude, a polar basin or one covering the entire globe being 
special cases. The general result is that for oceanic depths such as we 
know the monthly and fortnightly tides in such basins differ considerably 
from what the equilibrium theory gives, being in general considerably 
smaller. 

These results are decidedly puzzling when compared with observation, 
for the observed tides would then be larger than the computed tides of 
Darwin, Hough and Goldsborough instead of being smaller by an amount 
representing the yielding of the earth to the tide-producing forces. Dar- 
win's solution was re-examined critically by the late Lord Rayleigh.* He 
reaches the conclusion that the solution is a very special one that applies, 
of course, to the ideal water-covered globe postulated, but which has little 
relation to our actual oceans, interrupted as they are by continental bar- 
riers. He says : "H this conclusion be admitted, the theoretical fortnightly 
tide will not differ materially from its equilibrium value, and Darwin's 
former calculation as to the earth's rigidity will regain its significance." 
After a word of caution about possible exceptional conditions he con- 
cludes : "In any case I think that observations and reductions of the fort- 
nightly tide should be pursued. Observation is competent to determine 
not merely the general magnitude of the tide but the law as dependent 
upon latitude and longitude. Should the observed law conform to that 
of the equilibrium theory, it would go a long way to verify d posteriori 
the applicability of this theory to the circumstances of the case." 

Rayleigh's belief in the legitimacy of calculating the fortnightly tide — 
and A fortiori the monthly tide — from the equilibrium is supported by the 
opinion of Love' and there is still another reason for accepting this idea, 



^Proceedings of the Royal Society of London, 40 (1886), 337, or "Scientific 
Papers," I, 366. 

* Philosophical Transactions of the Royal Society of Lofidon, 189, 1897, 201, and 
191, 1898, 139. Some account of Hough's work is given in Darwin's article on 
''Tides" in the eleventh edition of the Encyclopaedia Britannica, parts of which are 
given also id Darwin's "Scientific Papers," I, 347. 

* Proceedings of the London Mathematical Society, Vol. for 1914-15, 31 and 207. 

* London, Edinburgh and Dublin Philosophical Magazine, 5, 1903, 136. 
'"Some Problems in Geodynamics" (Cambridge, England, 1911), 51. 



20 GEODESY 

namely, the eflFect of friction. Hough^ evaluates the modulus of decay 
under friction for various types of oscillation. The modulus of decay is a 
time of the same order of magnitude as the period of an oscillation that 
is slow enough to conform approximately to the equilibrium law. For 
oscillations most nearly corresponding to the long-period tides and with 
the laboratory value of the coefficient of viscosity of water he found 
moduli of the order of magnitude of ten years. But this use of the 
laboratory value of the viscosity seems to be fallacious. The laboratory 
value applies to the so-called laminar motion, while the motion in the 
actual ocean is turbulent. When we call the motion turbulent, we say in 
effect that we do not understand it very well ; but it is known that if we 
attempt to represent turbulent fluid motion by equations of the same form 
as are used for laminar motion, then the coefficient of viscosity in the 
latter, which is the laboratory coefficient, must be replaced by a coefficient 
of virtual viscosity many times greater. Ekman found for water that the 
coefficient of virtual viscosity was 15,500 times' greater ; for air, Taylor 
fotmd the ratio of the virtual viscosity to the laboratory value to be 
between 6,000 and 50,000.' It is not to be supposed tliat any one ratio of 
virtual coefficient to laboratory coefficient would apply under all condi- 
tions, but if any such virtual coefficient as is here suggested were used 
instead of the laboratory value, Hough's modulus of decay would be 
greatly reduced and the equilibrium theory would apply to tides of com- 
paratively short period, even apart from the effect of continental barriers. 

It seems to me, then, that it is pretty safe to assume that the monthly 
and fortnightly tides conform quite closely to the equilibrium theory and 
that it would be well worth while to resume the study of these tides for 
the light that they may throw on the rigidity of the earth. The only 
discussion of the observations since Darwin's original one is due to 
Schweydar,^ in which are discussed observations at 43 ports covering 194 
years. There must be available among all the harmonic analyses of tides 
that have been made since that time a great deal of material still unutilized. 

In regard to the utilization of this material and the procurement of new 
material there are three suggestions I should like to make. 

First: In securing the observations care should be taken that the tide 
gauge has a firm foundation. Tide gauges. are frequently located on docks 
supported by piles, or on made ground. If the cost could be afforded, 
it would be desirable to place them, if necessary, at some little distance 
from the water in order to get a good foundation, and to connect the 
gauge with the water by a large pipe. Incidentally, if a firm foundation 

^Proceedings of the London Mathefnaiical Society, 28, 1896, 264. 

•These values arc taken from a paper by McEwcii: Ocean Temperatures, their 
relation to Solar Radiation and Oceanic Circulation ; miscellaneous Studies of Agri- 
culture, Biology, Semicentennial Publications of the University of California. Other 
examples of very wide diflferences between laboratory and field values are also given 
by McEwen. The work of Ekman and Taylor is found respectively in the Arkiv 
for Matematik, Astronomi och Fysik 2, 190S, 1. and in the Philosophical Transac- 
tions of the Royal Society of London, 215, Ser. A, 1915, 1. 

• Beitrage zur Geophysik, 9, 1908, 64. 



GEODESY 21 

were assured, the tide records would be valuable in studying the secular 
rising and sinking of the coast. Too many long series of tidal observa- 
tions that would have been valuable for this purpose in the past have been 
rendered useless for lack of connection with well-established permanent 
marks. Schweydar deduced from his discussion of the tides an eflFective 
rigidity of the earth rather less than that of steel and suggests that the 
discrepancy between this result and the higher rigidity obtained from the 
variation of latitude may be due to a plastic stratum beneath the crust. 
He seems to have abandoned later his belief in this plastic stratum. Per- 
haps such a stratum exists, after all, but it may consist simply of the 
alluvial ground, mud or made land on which some of the tide gauges are 
situated. 

Second : In reducing a year's tidal observations at a place to obtain the 
long-period tides it is found that the tides are much entangled with one 
another. To separate them Darwin gives a rather tedious process of 
successive approximations. It is possible to dispense, with these repeti- 
tions at the price of a rather heavy piece of preliminary computation that 
is done once for all series of a given length, such as a year. If many 
long-period tides are to be reduced, it would be well worth while to do 
this preliminary work. Furthermore, Harris has suggested that if four 
consecutive years be taken together, the several long-period tides will 
separate satisfactorily from one another and the computation will be 
simpler. 

Third : In the final discussion we seek to obtain the earth tides from 
the difference between the theoretical tides on a rigid globe and the ob- 
served tides. Now, even accepting the comparatively simple equilibrium 
theory, which we are at present supposing to be adequate, the tides on 
a rigid globe have not been evaluated as accurately as could be vrished. 
The difficulties are the attraction of the water on itself and the presence 
of the continents. Either difficulty by itself is readily overcome. If there 
were no continents and the globe were covered with water, a simple factor 
derived from the fundamental principles of spherical harmonics would 
take care of the self -attraction of the water. On the other hand, if we 
disr^ard the self-attraction of the water, the influence of the continents 
can be allowed for as Darwin and Turner^ have done in following Sir 
William Thomson's (Lord Kelvin's) suggestion. 

It is the combination of the two circumstances, neither of which is 
troublesome by itself, that makes trouble, for the resultant of the two 
cannot be had by simply superposing two corrections. The total effect 
cannot be very large, but the modulus of rigidity is rather sensitive to 
changes in the ratio of the observed tide to the theoretical tide, especially 
if this ratio be near to unity, so that it seems perhaps quite possible that 
the modulus of rigidity may be changed as much as thirty or forty percent 
by the application of the corrections above mentioned. 

• Proceedings of the Royal Society of London, 40, 1886, 303, or Darwin's "Scien- 
tific Papers/' I, 328. 



22 GEODESY 

The evaluation of this correction of the combined eflFect of the conti- 
nents and the self-attraction of the water seems to me a problem worthy 
of study. No advance seems to have been made since Poincare's paper/ 
in which he works out a solution very elegant in conception, but one 
which, as Poincare himself says, would lead to calculations far too com- 
plicated to be practicable even if the shore line of the continents were 
arbitrarily simplified into a rude approximation to its actual form. I 
believe, however, that it may be possible to solve the problem numerically 
by a laborious process of successive approximations, involving the prepa- 
ration of maps showing the equilibrium tide corrected for the continents 
alone, and the reading of these maps for many points on the earth, much 
as contour maps are read to obtain the deflections of the vertical. The 
labor would be more than an individual investigator would care to under- 
take, but might well be within the means of an institution. Perhaps the 
theory of integral equations in its recent developments might afford means 
of lightening the labor. 

EARTH TIDES AND THE SHORT-PERIOD OCEANIC TIDES 

In discussing observations of earth tides as a means for obtaining the 
elastic constants of the earth — observations made either with horizontal 
pendulums or with Michelson's tube and interferometer — it is important 
to have a knowledge of the oceanic tides. This statement applies to tides 
of all periods, but these remarks apply more particularly to tides of short 
period, i. e., to the diurnal and semidiurnal tides. Tides of longer period 
have just been discussed. 

The shifting mass of tidal water exerts a direct gravitational effect on 
the horizontal pendulum or on the liquid in the tube, and the direct 
effect is reinforced by the tilting of the earth's crust under the shifting 
load of tidal water. The periods of these effects are precisely the periods 
of the tide-producing forces ; hence it is impossible to make an adequate 
estimate of the yielding to the tidal forces of the solid earth as a whole 
until the direct and indirect effects of the oceanic tides have been allowed 
for. 

Probably the most satisfactory determination of the earth tides is that 
of Michelson and Gale,* and it is noteworthy that their observations were 
made at Williams Bay, Wisconsin, which is some 800 miles distance from 
the ocean. The yielding of the earth deduced from the north-and-south 
displacements is nearly the same as that deduced from the east-and-west 
ones and the yielding deduced from the diurnal declinational tide, O^, is 
nearly the same as deduced from the principal semidiurnal tide, M,. 

This satisfactory state of affairs no longer obtains with some of the 
observations taken elsewhere with the horizontal pendulum. Keeker's 



^Journal de Mathimatiques Pures et Appliquies, 2, 1896, 57. 

• Journal of Geology, 22, 1914, or the identical article in the Astrophysical Journal 
for March, 1914. An important correction is given in Science, 50, 1919, Z27, Defi- 
nitive results will be found in the Astrophysical Journal for December, 1919. 



GEODESY 23 

results at Potsdam,^ which seemed to show a greater yielding of the earth 
in the meridian than in the prime vertical, have been a standing puzzle; 
attempts to explain this peculiarity as due to the rotation of the earth 
have been unsatisfactory.' 

More recent observations by Schweydar with horizontal pendulumB at 
Freiberg in Saxony* show anomalies also. Perhaps these anomalies are 
due to the inferior accuracy of the horizontal pendulum as compared with 
Michelson and Gale's apparatus, but it seems to me probable that the un- 
eliminated effects of the oceanic tides may also play a part.^ This effect 
has never been calculated, so far as I know, and has been assumed to be 
so small as to be practically negligible, but, as we shall shortly see, there 
are reasons for questioning this assumption. 

The only serious attempt to allow for the oceanic tides, so far as I 
know, is due to Prof. Shida" of Kyoto University, Japan. He observed 
with horizontal pendulums for a year at Kamigamo Geophysical Observa- 
tory, near Kyoto. In Japan it is, of course, impossible to get far from 
tide water, and though the tides in the surrounding waters are not par- 
ticularly large, but rather the contrary, still considerable effect is to be 
looked for. Harris's cotidal maps* were used for the M, component. 
They are based on actual observation for the coast, but necessarily on 
theory and inference for the open sea. For the Oi component special 
maps were drawn from the somewhat meager data available. From the 
maps the gravitational effects of the tidal water was read off just as the 
topographic deflection of the vertical may be read. The effect due to the 
yielding of the earth's crust was also computed on the most plausiSle 
assumptions practicable. The actual computation is not unlike that of 
the deflection of the vertical ; the result comes out that the deflection due 
to the tilting under the tidal load is about twice the direct gravitational pull 
of the load itself, and the two corrections combined were of the same 
order of magnitude as the earth tides proper. For example, the observed 
Oi tide on the pendulum swinging northwest-southeast came out 

+0:00525 cos ^-hOlWOSg sin t 

while the total deflection in the same direction due to the ocean tides was 
computed as 

+0:00410 cos *— 0.:00250 sin / 



^ "Beobachtungen an Horizontalpendeln tiber die Deformation des Erdkorpers 
tinter dem Einflusz von Sonne tind Mond/' Veroffentlicfaungen des Konigl. Preuss- 
ztschen Geodatischen Institutes n. f. no. 32, Berlin, 1907, and Heft 2, n. f. no. 49, 
Berlin, 1911. 

'See Love: "Problems in Geodynamics" (Cambridge, England, 1911), 75. 

' "Bericht uber die Tatigkeit des Zentralbureaus der Intemationalen Erdmessung 
im Jahre 1920," 6. 

^OrlofTs observations at Dorpat (reported in Astronotnische Nachrichten, 1S6, 
1910, 81) show a peculiarity similar to Hecker's but to a less degree. Dorpat is 
farUier removed than Potsdam from the influence of the large tides in the Atlantic 

' "Memoirs of the College of Science and Engineering," Kyoto Imperial University, 
IV, no. 1 (Nov., 1912). 

• Manual of Tides. Part IV B (Report of the U. S. Coast and Geodetic Survey 
for 1904, appendix 5). 



24 GEODESY 

where / is the hour angle of the fictitious O^ tide-producing body of the 
harmonic analysis. Evidently any inference drawn from the uncorrected 
earth tides would be quite wide of the mark. The computation was ex- 
tended to a distance of 40° of great circle (nearly 2,800 statute miles) 
from the station. This was considered sufficient in view of the meager- 
ness of the tidal data and the approximate nature of the work, but it 
should be remarked that the zone between SO"* and 40° gave in some cases 
a result equal to more than one-tenth of the whole correction, suggesting 
the desirability of extending the calculation to even greater distances. 

When we consider the great areas of ocean that lie within 40° of any 
one of the European horizontal-pendulum stations, it seems rash to assume 
without careful calculation that we may neglect the effects of the oceanic 
tides on the observed earth tides, and it may even appear desirable to see 
whether Michelson and Gale's result may not be susceptible of improve- 
ment by appl3ring the correction for oceanic tides. 

The primary difficulty with calculations of this sort is our lack of knowl- 
edge of tides in the open sea. We have Harris's cotidal lines, and it may 
be said that when these were used for reducing the Kyoto observations 
the results obtained seem, quite satisfactory, thus verifying to a certain 
extent the theories on which the lines were based. But at best this is 
theory rather than observation, and Harris himself was as keenly aware 
as anyone else of the incompleteness of' his work and the necessity of 
verifying it by observation. 

The direct observation of tides at sea is a problem beset with difficulties. 
To observe tides by means of soundings repeated every hour or so at the 
same point seems impracticable on account of the great depth to be 
sounded, rendering an accuracy of a foot or less impracticable, and on 
account of the difficulty of recovering the same point. Pressure gauges 
in one form or another have been suggested, but the instrument that will 
sustain the load of a thousand fathoms of water and at the same time be 
sensitive to variations in that load of a foot or so has not yet been 
devised.* 

It has occurred to me, however, that the question of tidal oscillations 
at sea could be approached somewhat differently, namely, by a study of 
the horizontal oscillations, that is, the tidal currents. In the open sea 
these tidal currents would, of course, be small, but not always too small 
to be detected and studied. Given a good knowledge of the tidal currents, 
the tidal rise and fall could be inferred with fair certainty. The relatively 
large tidal currents are to be looked for near the nodal lines of the sta- 
tionary tidal oscillations, and Harris's theory will indicate plausible places 
in which to look for such nodal lines. 

What has chiefly impressed me with the possibility of measuring tidal 
currents at sea was the reduction that I made for the late Dr. Harris of 



^ A recording tide gauge for work at sea invented by M. Fave, a French hydro- 
graphic engineer, that is said to have given good results at Dover, England, and in 
ftie Thames Estuary, is mentioned in the Observatory, 43, Aug., 1920, 2/9. 



GEODESY 25 

observations taken some thirty-five years ago by Lieut. Pillsbury/ as he 
was then, later Rear Admiral Pillsbury. They were not made with the 
study of tidal currents chiefly in view, but for the exploration of the 
Gulf Stream. Dr. Harris had them worked over again by more modem 
methods to see what information about tidal currents could be extracted.^ 

The series were all short, a few days at the most, and some of them 
did not put in evidence an unquestionable tidal current, but a number of 
them did. A plotting of these latter showed that the results of the approx- 
imate harmonic analyses that were made could not be far from the truth. 
The velocities found ranged in general from 0.05 to 0.3 knot. It may be 
of interest to remark that the times and directions of the current were 
in general agreement with Harris's theory of stationary tidal oscillations. 
The observations, of course, were made before this theory was formu- 
lated, but they were not reduced for tidal purposes till some time after 
the theory was published, so that they serve as a partial confirmation of it. 

H an expedition were sent out to determine tidal currents at sea in 
somewhat the way here suggested, it would have to occupy one spot for 
several days, or preferably longer. While the vessel remained on the 
spot for current observations there would be an excellent opportunity for 
other kinds of scientific observation, magnetic, geophysical and biological. 
The intensity of gravity at sea is a great desideratum in geophysics and 
as soon as adequate apparatus is devised for the purpose observations of 
gravity should certainly be made in connection with observations of the 
currents. 

EARTH TIDES AND THE VARIATION OF LATITUDE 

Just as we may make a harmonic analysis of the readings of a hori- 
zontal pendulum or a Michelson tube in order to evaluate the earth 
tides, so for the same purpose we may make a harmonic analysis of 
latitude observations. In all three cases we are observing the direction 
of the vertical or plumb line. In the first two cases the vertical is referred 
to some mean position determined on the instrument itself and connected 
with the ground immediately around it, and thus shifting its position as the 
ground tilts under the influence of the tide-producing forces in the earth 
and under the load of the oceanic tides. In observations of the latitude 
the direction of the vertical is referred not to the ground round about the 
instrument, but to the direction of the earth's axis. The tilting of the 
ground is allowed for when the level readings are taken and the proper 
corrections for them applied. This absence of the tilting enables us to 
get a hold on the problem of the earth tides somewhat different from 
that afforded by observation with the horizontal pendulum or with the 
tube and interferometer. 



* Appendices to Reports of the U. S. Coast and Geodetic Survey for 1885, 1886, 
1887, 1889 and 1890. More especially that for 1890, which contains an account of 
the apparatus used. 

' For the tidal data deduced see Harris's Manual of Tides, Part V (U. S. Coast 
and Geodetic Survey, Report for 1907, Appendix 6), 409-13. 



26 GEODESY 

The latitude observations most obviously appropriate for such a har- 
monic analysis are those of the international latitude service and I believe 
that they should be systematically discussed in this manner. Some pre- 
liminary work of this sort has been done by Shida and Matsuyama/ and 
Shida has proposed to the International Geodetic Association that it 
undertake the work. Further work on the subject has been done by 
Przbyllok, whose work has perhaps already been published, though with- 
out coming generally to the attention of scientists on this side of the 
water' on account of still unsettled international conditions. I believe 
the International Geodetic and Geophysical Union should plan to continue 
the work. 

SUMMARY 

The observation and reduction of the long-period oceanic tides should 
not be neglected. The equilibrium theory has not been as fully developed 
as is desirable and an attempt should be made to allow both for the self- 
attraction of the water and for the presence of the continents. When this 
has been done and observation compared with theory, it seems probable 
that a good value for the long-period earth tides will result. To get good 
results for the short-period earth tides the oceanic tides of like period 
must be known and their effects allowed for. One promising means of 
getting this knowledge seems to be a study of the oceanic tidal currents, 
which appears to be more feasible than the direct observations of the tides 
themselves. While the currents were being observed other scientific obser- 
vations could be made. The earth tides affect the plumb line and their 
effects must therefore be present in the observations of the International 
Latitude Service. It is desirable to continue the discussion of these obser- 
vations in order to throw light on the earth tides. 



* "Memoirs of the College of Science and Engineering/' Kyoto Imperial University, 
IV, no. 1, 1912. 277. 

' "M. le. Prof. Przybyllok a tach^ de d^terminpr plus exactement les constantes de 
qaetques termes p^riodiques dont les observations du service international des lati- 
tudes avaient fait connaitre Texistence; il s'est surtout occupe a deduire des obser- 
vations astronomiques les constantes de la maree M| dans le moovement de la 
verticale de la terre consider^e comme corps 61astique. Les resultats seront public 
sous peu dans les Astron. Nachrichten.** — From Rapport sur les Travaux du Bureau 
Central de I'Association G^d^ique Internationale en 1920, p. 3 (dated Jan., 1921). 



SOLAR RADIATION AND TERRESTRIAL PHENOMENA 

By C G. Abbot 

SOLAR RADIATION 
Its Vabiabiuty and Its Relations to the Atmosphere 

For more than fifteen years the Astrophysical Observatory of the 
Smithsonian Institution has been engaged in making measurements of 
the radiation of the sun. These measurements have indicated that the 
sun's emission is variable. The Institution now maintains two stations — 
one in Arizona and the other in Chile — for observing the solar variability. 
Telegraphic reports of the results obtained in Chile have been forwarded 
to Buenos Aires and Rio de Janeiro for the use of the meteorological serv- 
ices of Argentina and Brazil. 

The variation of the solar emission is of two kinds — one, of long 
period, associated with variations in the visible solar phenomena like sun- 
spots, faculae, prominences, and the like; the other, of short irregular 
period, apparently depending upon inequalities of radiation in different 
directions, which, rotating with the sun, produce at the earth the variation 
just mentioned. This hypothesis is confirmed by the photo-electric cell 
observations of Guthnick, who found variations of Saturn occurring 
earlier or later than corresponding ones in solar radiation observed in 
Chile, depending on the heliocentric longitudes of the earth and Saturn. 
Higher values of the solar emission occur when the sunspots are most 
numerous, which gives rise to a paradox, because the temperature of 
most meteorological stations is lower at sunspot maximum. This negative 
correlation between solar emission and terrestrial temperature may be due, 
however, to a variation in terrestrial cloudiness or to other variations in 
the composition of the terrestrial atmosphere. It has long been known 
that a close correlation exists between the sunspot numbers and the varia- 
tions of terrestrial magnetism. The intermediary mechanism producing 
this relation is not known. However, it has long been suspected to be 
due to the bombardment of the earth by ions shot out from the sun. If 
this is the case, these ions may assist in the production of cloudiness and 
have also influence in the production of ozone in the higher atmosphere, 
and thus in one or both of these ways operate on terrestrial temperatures. 

Observed variations of the sun have hitherto lain within the maximum 
range of about 12 percent. It is rare that fluctuations exceeding 3 percent 
occur within a single week or fortnight. Such studies as have been made, 
notably those of Mr. Clayton of Buenos Aires, indicate that corresponding 
to these small fluctuations of the sun there may be variations of several 
degrees in the mean temperature of meteorological stations. Accordingly 
it is highly desirable to be able to detect with certainty fluctuations of the 
solar emission of the order of 1 percent. This is a hard requirement, 
and it is only within the last year that the establishment of the Arizona 

27 



28 METEOROLOGY 

• 

and Chile stations has warranted the hope that it can be met. Prior to 
that time, errors of 2 or more percent were probably not infrequent in 
solar radiation determinations at Mt. Wilson, which imtil 1918 was the 
only station in the world where the solar constant observations were being 
made. Hence we must be required to wait for another decade of years 
before having a thoroughly satisfactory series of solar radiation measure- 
ments to compare with meteorolc^cal observations. It would be a very 
great advantage if two additional solar stations could be equipped in 
Northern and Southern Africa in the most cloudless and favorable con- 
ditions, so that there would be four stations operating under a homogene- 
ous scheme for determining the variability of the sun. 

The question arises whether observations of the visible phenomena upon 
the sun's surface, such as sunspots, faculx, prominences, or the like, or 
the observation of terrestrial magnetism, which, as has been said, is closely 
related to solar phenomena, may furnish some index to solar conditions 
as valuable as the difficultly obtained determinations of solar radiation. 
Many statistical comparisons have been published on relations of sunspots 
and terrestrial phenomena, and to a less degree the other solar appearances 
have also been correlated thereto. It must be confessed, however, that 
the result of this enormous amount of work has not been as favorable as 
would have been hoped. In almost all instances, relations which appeared 
to hold for a few months or years are reversed in other months or years. 
Except for the well-known correlation of terrestrial magnetism with the 
sunspot numbers, there is hardly any other pair of phenomena which 
would be universally accepted as related. Whether a similar disappoint- 
ment will attend the proposed studies of solar radiation can not yet be 
foretold. 

Of variable terrestrial influences, the most profoundly active on the 
solar radiation are the water vapor of the earth's atmosphere and the 
clouds and haze which are formed from it. Water vapor itself produces 
powerful absorption bands in the red and infra-red spectrum. Associated 
with dust, water vapor produces haze which is effective throughout the 
visible spectrum, and more effective the shorter the wave-length. A great 
mass of observations of these things has been made by the Smithsonian 
Institution in connection with its studies of the solar constant of radiation. 
My colleague, Mr. Fowle, has published a number of papers covering the 
results of these studies of the subject. 

Water vapor itself removes from the direct solar beam which encircles 
the earth somewhere from 10 to 20 percent of its intensity, depending 
upon the humidity of the air and other circumstances. The haze may 
readily produce far greater reduction to the intensity of the solar beam. 
In addition, we have the clouds. My colleague, Mr. Aldrich, took advan- 
tage of the presence of the balloon school near Mt. Wilson to observe 
from a balloon the reflecting power of the upper surface of the vast oceans 
of fog which come in from the Pacific and cover the San Gabriel Valley. 
He found that a continuous sheet of level cloud would reflect away ap- 



METEOROLOGY 29 

proximately 77 percent of the solar rays. As the earth is on the average 
about 50 percent cloudy^ the great effect of these factors on terrestrial 

temperatures is obvious. 

Cloud measurements are among the most unsatisfactory which are re- 
corded by meteorologists. They depend largely on the personal equation 
and indeed no really adequate statistical study of them has hitherto been 
available. The preparation of proper automatic observing apparatus and 
the study of observations of clouds are highly desirable. 

TERRESTRIAL RADIATION 
Its Relations to the Atmospheie 

When we take up the question of the terrestrial radiation, we deal with 
another Tegion of wave-lengths from that which is covered by the prin- 
cipal incoming solar rays. The direct rays of the sun and the skylight 
are almost altogether confined to the region of wave-lengths extending 
from 0.3 micron to 3 microns. The region of the terrestrial radiation 
extends from 5 microns to 50 microns. Spectrum measurements have 
been made through a part of this region by my colleague, Mr. Fowle, 
who used an artificial source of light and a very long column of air of 
known humidity and carbon dioxide content. In this way he determined 
the influence of terrestrial humidity upon the rays as far as 17 microns. 
Beyond that, from 17 to 50 microns, no adequate studies have been made, 
and indeed the difficulty of making them is immense. Apparently the 
.water vapor existing in a column of air a quarter of a mile long cuts off 
all terrestrial rays except in the region from 8 microns to 13 microns. 
In this region, water vapor is almost perfectly transmissible and in this 
region occurs, therefore, almost all of the terrestrial radiation which, 
rising from the earth's surface, escapes to space and tends to cool the 
earth. No constituents of' the air at the earth's surface seem to affect 
the transmissibility of rays between 9 and 12 microns in wave-length, but 
the matter is quite different in the upper atmosphere. Mr. Fowle found 
that a strong band of absorption occurs in the direct solar beam squarely 
in the middle of this^very transmissible region. It appears from some 
measurements of K. Angstrom that the cause of this band is ozone. Thus, 
owing to the accidental position of this powerful absorption band in the 
middle of the only region where the other atmospheric constituents are 
almost perfectly transmissible, ozone plays an important part in deter- 
mining terrestrial temperatures. 

A research ought to be undertaken to determine the influence of ozone 
in this region of the terrestrial spectrum, the variations of its amount in 
the atmosphere, and, in short, the dependence of the terrestrial tempera- 
tures on ozone. This research will be very difficult, owing to the long 
wave-lengths of the rays involved and owing to the occurrence of ozone 
high up in the terrestrial atmosphere. The investigation would involve 
the determination of the dependence of the ozone content of the atmos- 
phere on solar radiation as well as on influencing terrestrial conditions. 



30 METEOROLOGY 

Hitherto the measurement of the outgoing terrestrial rays — that is, of 
the so-called nocturnal radiation — ^has been very unsatisfactory on account 
of the lack of a surface which radiates these rays perfectly. Blackened 
flat surfaces have been used in the instruments employed, but the black- 
ening by means of smoke, lampblack paint, or platinum black are all 
unsatisfactory because these substances are not full radiators and absorb- 
ers for the very long wave-lengths involved. Smoke, for instance, is 
strongly transmissible beyond 10 microns, and lampblack paint falls off 
in its absorption very rapidly beyond 15 microns. It is necessary, in order 
to obtain exact knowledge, to employ some radiating and absorbing instru- 
ments which are perfectly radiating and absorbing by reason of their 
shape ; that is to say, which approximate to the so-called absolutely black 
body. 

Hitherto, only one such instrument has been developed, an instrument 
of which there is yet no published description, namely, the honeycomb 
pyranometer, or Melikeron, recently invented by Abbot and Aldrich. 
This instrument consists of 200 deep cells made by fluting a ribbon of 
thin manganin, the whole presenting a surface comparable to a honey- 
comb, in which the rays penetrate deeply and are absorbed by repeated 
reflections. The heat produced by the rays of the sky or outgoing to the 
sky can be compensated by the introduction of the energy of the electric 
current. This instrument is but just past its experimental stage, and only 
a few as yet unpublished measurements have been made with it. 

Spectrum observations ought also to be undertaken in the region of 
wave-lengths from 15 to 50 microns. Rock salt is no longer available in 
this region, so that some special optical instrument, either a special grating 
or a special prism to be made of potassium iodide, must be employed. 



NEEDED INVESTIGATIONS 

It will be seen from these remarks that the most outstanding needs in 
the investigation of radiation for meteorological purposes are: 

First, the continuance of accurate observations of the variation of the 
sun. These measurements are now going on under the auspices of the 
Smithsonian Institution in Arizona and Chile, but should preferably be 
supplemented by the provision of two additional stations, perhaps in North 
and South Africa, so that variations of the sun could be adequately 
studied every day in the year. Twenty-seven thousand dollars a year 
would provide the two stations within two years and maintain them 
thereafter perpetually. 

Second, the painstaking studies of terrestrial cloudiness, its causes and 
its effect on the incoming of solar radiation. 

Third, the study of the quantity and variability of ozone in the upper 
atmosphere, its dependence on solar and terrestrial conditions, and its 
influence on terrestrial temperatures. 

Fourth, extensive studies with the "black-body" nocturnal radiation 



METEOROLOGY 31 

instrument, and if possible the development of new instruments of that 
class. 

Fifth, an investigation of the effects of terrestrial atmospheric con- 
stituents on rays between the wave-lengths of 15 and 50 microns should 
be undertaken. This involves the development of special optical means 
to take the place of rock-salt prism as a dispersing medium, since rock salt 
is non-transmissible to the rays in question. 

RELATIONS BETWEEN SOLAR ACTIVITY AND ITS 

VARIOUS ASPECTS AND THE PHENOMENA 

OF TERRESTRIAL WEATHER 

By C F. Hakvin 

My contribution to this discussion is an appeal for a more careful and 
consistent recognition of the effects and operations of chance in the study 
of data which may be employed in investigations of solar and terrestrial 
relations, periodicities, etc. Weather conditions, atmospheric transmission 
of radiation, magnetic phenomena, sunspots, observed intensities of radia- 
tion, and values of like phenomena are subject to large and irregular 
accidental variations, due account of which must be taken in reaching 

conclusions. 

SOLAR RADIATION 

My point of view is illustrated in an admirable manner by figure 1, 
which serves to show how weak the observational basis still is to justify 
the claim that there are important irregular changes from day to day in 
the intensity of solar radiation. 

Discussion of diagram. — ^The vertical lines of the diagram represent 
throughout each group 25 observations, counted from the beginning of 
the group. The points on the zigzag lines are simply consecutive obser- 
vations without reference to the interval of time between observations. 

The chronological sequence of the groups of data is represented by the 
numbers 1, 2, 3, etc. Only a few observations were made between 1902 
and 1907 at Washington at wide intervals. From 1905 to 1918 (groups 
2 to 7, inclusive) the observations were made at Mount Wilson, Calif. 
In all these cases the interval between observations is as nearly as 
possible one day, although periods of bad weather frequently caused two 
or three, or more days sometimes, to intervene. As a rule, observations 
were made only from June to November. 

Extreme variability is shown in the observations in group 1. Groups 
2, 3, 4, 5, and the first portion of 6, show distinctly a lower order of 
variability, although occasional extremely high and low values occur in- 
frequently. 

Beginning at K, group 6 for 1912, great variability again appears in the 
consecutive values extending into, although diminishing during, 1913. 
The high value at K, group 6, marks the arrival at Mount Wilson, Calif., 
of the dust from the Katmai volcanic eruption. 



32 



METEOROLOGY 




So 

Id 

'J 

S 

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if . 

82 

E 

tt ♦* 

cog 

4^ 2k 
K^ 
it 

M 

*«^ B 

C o 
of 

O viH V^ 

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B 
ft 



B 



£5^ 



METEOROLOGY 33 

From 1914 to 1918, well after the atmosphere had cleared itself of the 
Katmai dust, the variability became quite similar to observational results 
at Mount Wilson prior to the Katmai year, 1912. 

Group 8 represents the observations at the station at Calama, Chile. 

All observations, including the first portion of group 8, were made by 
the holographic method. 

Finally, the last group of observations, ending December 31, 1919, were 
made by a new empirical method based on the bolc^aphic method but 
permitting two or three observations to be made the same day, thus giving 
a mean average value for a day of higher accuracy. 

This diagram tells a very important story with great force and plain- 
ness. Great variations in consecutive values of intensity mark the early 
observations in Washington with imperfect equipment and poor atmos- 
pheric conditions. 

Observations at Mount Wilson from 1905 to 1912 show far more nearly 
constant values of radiation until the arrival of the atmospheric dust from 
the Katmai volcanic eruption, after which day-to-day or consecutive values 
showed great variations. Everyone probably ascribes these increased 
variations, not to increased solar activity, but to inaccuracies of measure- 
ment due to atmospheric dust. The large variations disappeared with the 
dust. Furthermore, some increased accuracy (smaller variations) char- 
acterized the observations at the station at Calama, Chile, either because 
of the better instrumentation, greater observational experience, or better 
observing conditions, or all of these in combination. 

Finally, it is most striking that a further marked reduction in day-to-day 
variability immediately resulted from the introduction in 1919 of the 
pyranometer method of observation. 

The percentage probable error of a single value has been carefully 
computed for each group of observations and the results are showii 
graphically in figure 2. 

Entirely terrestrial causes easily explain the great changes and gradual 
diminution in variability shown by the observations, the accuracy of which 
has been wonderfully increased by improvements in instruments, methods, 
and location of stations. What are now regarded as good observations 
for a single day's work show a probable error as low as 5 or 6 tenths of 
one percent. This is remarkable precision. This analysis of the whole 
body of radiation data brings one face to face with the important 
question : 

Is all of this 5 to 6 tenths of one percent of day-to-day variation in solar 
radiation intensities real error of measurement only? Or is part of it 
error of mieasurement and part real solar change f If the latter, what are 
the respective amounts of each variation f 

Some conclusive answer to this question is necessary before inferences 
and claims of solar and terrestrial correlations can be set up and justified. 

It can never be claimed, of course, that single daily values, however 
carefully made, are perfectly accurate. Probably simultaneous observa- 



54 



METEOROLOGY 



tions at several stations is the only answer to this question. Caution is 
necessary even here, because mere coincidence of variations due absolutely 
to errors only will come in to affect comparisons at two stations. If, for 
example, e is the probable variation of, say, a season's work at two per- 



mpTi 



mrr 




H- Mt. Wilson. Cal. 



KUlama 



Fig. 2. Height of bars shows probable error of an observation for a single day of 
the intensity of solar radiation as measured by the Astrophysicat Observatory of the 
Smithsonian Institution at Washington, Mount Wilson, Calif., and Catama, Chile. 



fectly equal stations, then for pure chance relations between values the 
variation c„ of the mean of the two must be 



<m 



VT 



This furnishes an interesting test to apply to the simultaneous obser- 
vations at Arizona and Chile when these are released by the Smithsonian 
Institution. 



TERRESTRIAL DATA 

No serious study of any kind dealing with hidden or obscure relations 
between data subject to large irregular variations should ever be under- 
taken without a careful application of the principles of probabilities and 
a consideration of the operation of the elements of chance upon the 
phenomena under study. 

In the discussion of this portion of the subject the author gave the first 



METEOROLOGY 



35 



public account of the mathematical and graphic device which has been 
designated The Periodocrite. 

Periodocrite^ is a word coined from Greek roots signifying a critic, a 
judge, a decider of periodicities, and is a name applied to a mathematical 
and graphic method or device which has been developed to aid in the 
conclusive separation of obscure and hidden cycles and periodicities pos- 
sessing a real existence from those whose essential features are only such 






""7 


W^t 


^^P 


tirfoi 


'ilclty 


r*"" 


1 


r 1 


1 7i 

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4 


















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1 


t 
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X 


X 

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A 


f' 


















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f J 


r A 


r .A 


F .4 


r .; 


f .4 


f 4 


f 4 


9 



Fig. 3. Rainfall periodocrite : X» Annual cycle five stations in Iowa, 
36>year record ;•, Annual cycle Washington rainfall, 50-year record; 
-f > Annual cycle Boston, Mass., 103-year record, very feebly defined; 
3, A 15-noonth sequence Iowa rainfall; other sequences, 15 months, 
16 months, one-ninth the variable sunspot period, like the circles, all 
fall in the class of perfect fortuity. 



as would result from, and can be explained by, entirely chance combina- 
tions of the data employed. 

The periodocrite does not disclose or discover the length of suspected 
periods or cycles. Other methods, such as the harmonic analysis, Schus- 
ter's periodogram, or any of the many methods which have been offered 
for this purpose must first be employed to ascertain the proper length of 
any suspected cycle. 

* Prof. C. F. Talman supplied this name from K^pio&)S, a period -{- Kpinyf , 
a judge, decider, umpire, from Kpcya, to separate, investigate, judge. 



36 METEOROLOGY 

The theory of the periodocrite depends upon the principle that in an 
entirely fortuitous combination of data the standard deviation, vn of a 
result made up of n individual observations in combination is given by 

the equation <rn ^—7=^ in which fr^\A the standard deviation of the orig- 
inal data not in combinations. 

Writing y= — ^ and x= -7= we get 

^o vn 

y=x 

which is the equation of a line of perfect fortuity passing through the 
origin of coordinates (see figure 3). It can also be shown that for perfect 
periodicity y=constant=l. 

The full account of this aid to scientific investigation of periodicities 
has been published in the Monthly Weather Review for March, 1921, to 
which the reader is referred for the development of this idea and certain 
related matters dealing with the discussion of meteorological data briefly 
outlined in the address. 



DAILY METEOROLOGICAL CHARTS OF THE WORLD 

By Edwaid H. Bowb 

INTRODUCTION 

Investigations in the field of general meteorology have been and con- 
tinue to be restricted and handicapped by the fact that there are not 
available to investigators daily charts of the world's weather. It is neces- 
sary in investigations in meteorology and particularly in weather fore- 
casting that problems now but imperfectly understood be considered from 
a world-wide viewpoint, for there can be no doubt that much that we call 
"weather^' is not of local origin, but has its inception in the general actions 
and reactions that involve at times the atmosphere over an entire hemi- 
sphere and possibly both hemispheres. Hence, investigation based on a 
study of daily synoptic charts for a limited area, such as Europe, the 
United States of North America, or of India, can lead to but an imperfect 
understanding of the general physical processes that are in operation to 
produce our day-to-day weather. Moreover, when it is understood how 
rapid are the changes in speed, direction of movement and magnitude of 



METEOROLOGY 37 

areas of high and low barometric pressure, there arises the natural desire 
to look into the observable facts over a world-wide area in an attempt 
to determine the causes of them. Meteorology without a world-wide 
weather map is laboring under difficulties as great, or greater, without 
realizing it, than astronomy without its star charts. Hence it is contended 
that many of the important problems of meteorology will not and cannot 
be solved until there be available daily synoptic charts of the various 
meteorological elements of, relatively speaking, the entire world. It would 
redound to our credit if the American Geophysical Union should become 
instrumental in bringing this about. 

NEED FOR WORLD-WIDE CHARTS 

There is reason to believe that meteorology has for its goal the making 
of accurate forecasts of' weather, temperature and wind for long periods 
in advance. Such an attainment would not only mark a distinct advance 
in the science of meteorology, but in its practical application would be of 
great economic importance to the life of the nation. 

The problem of making such forecasts has for years received considera- 
tion not only from meteorologists of good repute — scientifically speaking 
— but also from others untrained or at least not having a thorough grasp 
of the question. Many explanations of the frequently marked deviations 
from the normal that occur in the meteorological elements at any given 
place have been given publicity. Much attention has been given to the 
question of cycles, even more has been given to the question of sunspots, 
and recently attention has been focused on the so-called variations in the 
solar constant. But all these efforts fail to offer a method that permits 
the making of long-range forecasts of a sufficient degree of accuracy to 
have a practical application of any importance. 

One naturally inquires why nothing really definite has been evolved that 
might be useful in long-range forecasting, and the only possible answer 
that can be made is that the right combination has not yet been found. 

My impression is that the answer will probably be had from a prolonged 
and careful study of world-wide meteorological conditions, and this study 
is possible only in the event that daily S3moptic charts embracing the major 
part of the world are available. In my opinion all marked deviations from 
normal weather and temperature are associated with changes in magnitude 
and position of the so-called "great centers of action." Any material 
addition to our knowledge of these must come from the study of world 
charts, for it is only by such a method that we can hope to gain a more 
comprehensive knowledge of the general atmospheric circulation and the 
resulting changes in the centers of action. In Supplement No. 1, Monthly 
Weather Review, 1914 (Bowie and Weightman), it is stated that: 

Conspicaously abnormal pressures in the regions of these so-called "centers of 
action" are related to marked departures from normal weather and temperature 
condttions in the United States. Some authorities assume that these abnormal 
distributions of pressure are due to extra-terrestrial and others assert that they are 
due to terrestrial causes. If it be true that the solar output is a variable quantity. 



38 METBOROLOGY 

it is possible that the solar variations are associated with marked changes in pressure 
in the "centers of action/' and thus may be found a key for defining for consideraUe 
periods in advance the general character of coming weather changes for a given 
region. If on the other hand abnormal pressure distributions occur with an unvary- 
ing solar radiation, the causes thereof must be traced to a terrestrial source. The 
vanring effects of the nearly constant radiation on land and water surfaces and on 
the air under different conditions of temperature, water vapor content, dust content, 
etc., are sufficient in the minds of some writers to explain these phenomena, L e., 
the changes in the position and magnitude of the "centers of action." 

Regardless, however, of the cause of abnormalities in the "centers of action" the 
importance of their relation to the character and paths of storms in the United 
States is well recognized and therefore should be carefully considered in day-to-day 
weather forecasting in the United States. To illustrate: Of the centers of action 
that affect the weafiier conditions of the United States east of the Rocky Mountains, 
the subpermanent high over the middle latitudes of the North Atlantic Ocean i% 
perhaps the most influential. When this is well developed and stable, temperatures 
above the seasonal average are to be expected over the great central valleys and the 
eastern and southern states, and the areas of high and low barometer crossing the 
United States will move in high latitudes and pass on to the ocean by way of the 
St Lawrence valley. In fact, all prolonged periods of heat in the regions east of 
the Rocky Mountains occur simultaneously with the abnormal development of this 
subpermanent high. When, however, it is weak and ill-defined, cool weather prevails 
over the eastern half of the countiy. 

Again, the variations in the position and magnitude of the elongated subpermanent 
area of low pressure that normally extends from southeastern Alaska westward to 
Kamchatka, have a decided influence on the characters of, and courses followed by, 
storms that cross the United States. If this Aleutian low is north of its normal 
position, lows will move along our nortfiem border; whereas, if it is south of its 
normal position, lows will move far south of their normal tracks and stormy 
weather with great alternations in temperature will occur over the United States. 

Perhaps the best examples of unusual winters in the United States are 
those of 1917-1918 and 1920-1921. In the former, which was one of 
great severity, the pressure was abnormally high over Alaska and the 
Aleutian Islands ; while in the latter, which will go down in meteorological 
history as one of the mildest known, the pressure was much below the 
normal over those regions. 

To be able to formulate correct forecasts, a knowledge of the general 
circulation is fundamental. It is questionable whether a proper under- 
standing of the general circulation can be gained from monthly averages. 
It certainly is not as stable as the text books would lead us to believe, for 
there are frequently marked changes in both the surface and upper air 
flow. It has been customary to think of the general or primary wind 
circulations of the two hemispheres as separate and distinct, but this view 
is not tenable. A cursory examination of plate 14, "Bartholomew's Phys- 
ical Atlas,'' Meteorology, volume III, shows a tremendous seasonal inter- 
flow between the northern and southern hemispheres, indicating that the 
two systems of general circulation are in a way interlocked. In the winter 
of the northern hemisphere the air flows normally from the interior of 
Asia southward over the Indian Ocean, eastern Africa and the East 
Indian Archipelago on beyond the equator as far south as northern Aus- 
tralia; in the summer of the northern hemisphere a return flow takes 
place over essentially the same geographical area. No one can say, for 
the lack of the necessary data, whether these currents do not bring about 



METEOROLOGY 39 

profound changes from normal weather and temperature conditions over 
large areas outside the regions where these flows and counterflows are in 
operation, but it seems logical to suppose that such is the case. Further, 
the trades and antitrades are probably not fully understood. Certainly 
these wind systems undergo pronounced changes that are independent of 
the seasonal changes. In connection with the antitrades, Sir Napier Shaw 
in a recent number of Nature remarks : 

At the same time I may remark that I find it very difficult to grasp the meaning 
that is intended by "anti-trades." The original convection theory suggested that the 
anti-trade was the trade returning up aloft above its old patii, but, so far as I can 
understand the situation, the track of the wind from the equator must begin from 
the east and become southwest by what I will describe as the hurricane track. On 
the other hand, a southwest wind may be a part of the westerly circulation diverted ; 
the difference of origin of the observed southwesterly wind is of some dynamical 
importance. 

It seems possible that the antitrade may be a northward extension of the 
southeast trade of the southern hemisphere, which on crossing the equator 
is turned to the right by the deflective force of the earth's rotation, and 
being warmer and of less density, overruns the low-lying northeast 
trade. But this is not definitely known and sufficient data are not at hand 
to prove or disprove the assertion. 

Bjerknes has recently given meteorology the term "polar front," a line 
of discontinuity separating the polarward from the equatorward flowing 
winds, and he has urged the collection of daily meteorological observations 
from larger geographical areas that this "polar front" may be delineated 
on the weather charts for the aid of the forecaster. He believes this 
essential to forecasting, for the theory he advances places the origin of 
cyclones and consequently all marked variations in weather, temperature 
and wind changes along this line of discontinuity. His presentation of 
the idea of the "polar front" and its attendant phenomena is worthy of 
him, and augments the necessity of observations over large geographical 
areas in weather forecasting. 

It will be seen from the foregoing that meteorology must in the near 
future consider the question of securing observations from every accessi- 
ble place and assemblit^ them for the construction of daily world-wide 
weather charts at one or more great world centers for intensive study. 
First, there must be a skeletonized chart based on observations collected 
by cable, radio and land lines, and, second, a more nearly perfect and 
complete chart based on the same observations supplemented by those 
collected from remote land areas in which cable or radio is not available 
and from ships at sea. The former chart would serve for day-to-day 
forecasting; the latter, for study purposes and eventually for long-range 
or seasonal forecasting. 

HISTORY OF THE MOVEMENT FOR WORLD-WIDE CHARTS 

The need of a daily synoptic survey of the earth's atmosphere was co- 
incident no doubt with the beginning of synoptic weather charts, which 
was at approximately the middle of the nineteenth century. We learn 



40 METBOROLOGY 

that at the first meeting of the International Meteorological Congress, 
assembled at Vienna in 1873, a proposition was adopted to the effect : 

That it is desirable, with a view to their exchange, diat at least one nnifonn 
observation, of such a character as to be suitable for the preparation of synoptic 
charts, be taken and recorded daily and simnltaneonsly throogfaout the world. 

Later, on December 9, 1876, it was announced that the United States, 
through the Chief Signal Officer, U. S. A., no doubt inspired by the late 
Prof. Qeveland Abbe, then assistant to the Chief Signal Officer, was 
undertaking the task of establishing cooperation for the recording and 
exchange of simultaneous meteorological observations between the United 
States and the following named countries: Algeria, Austria, Belgium, 
Great Britain, Denmark, France, Germany, Italy, The Netherlands, Nor- 
way, Sweden, Switzerland, Turkey, Greece, Canada, the Hawaiian Islands, 
Dutch Guiana and Japan. This cooperation extended to naval and mer- 
chant vessels of these nations, and thus were secured the simultaneous 
observations of atmospheric changes over much of the northern hemi- 
sphere. Thus came about the "Bulletin of the International Meteoro- 
logical Observations," published by the Signal Service, U. S. A., for the 
years 1877-1887 — incomplete, it is true, as to world-wide weather maps, 
but a remarkable contribution which has left its impress on meteorology 
even tmtil today. 

An effort to accomplish the preparation of northern hemisphere weather 
maps by means of daily telegraphic reports for the purpose of extending 
the forecast period to cover the general weather of the United States was 
undertaken by the U. S. Weather Bureau in 1907, and the area covered 
by such reports grew until the outbreak of the Great War in 1914, when 
the scheme was unavoidedly interrupted. No other really effective efforts 
looking to the preparation and publication of even partial world-wide daily 
synoptic charts are known to me. 

PRESENT STATUS OF DAILY SYNOPTIC METEOROLOGICAL CHARTS 

Nothing approaching a world-wide daily synoptic chart is prepared and 
published by the meteorological service of any nation. Instead, every, or 
nearly every, national meteorological service decides for itself: (a) the 
scale of the map, (b) the units of measurement, and (c) to a greater or 
less extent the hours of observation. In addition to the various charts 
of land observations, charts are also made of the meteorological conditions 
over one or more of the oceans. Daily weather maps for their respective 
geographic areas are now prepared and published by the United States, 
Canada, Mexico, Argentina, Chile, Brazil, Japan, China (Zi-ka-wei Ob- 
servatory), Australia, India, South Africa, Great Britain, France, Portu- 
gal, Belgium, The Netherlands, Norway, Sweden, Denmark, Germany, 
Austria ( ?), Russia ( ?) and others. There is thus available a tremendous 
mass of valuable data awaiting action that will assemble them into one 
standard, world-wide weather map which will permit investigations in 
meteorology to be carried beyond any point now possible. 



METEOROLOGY 41 

RECOMMENDATIONS 

This matter is believed to be of such importance at the present time that 
it is contemplated recommending in appropriate form that some action be 
taken by the Geophysical Union for the accomplishment of the desired 
objects through international cooperation. 

There is no doubt in the minds of those familiar with the present status 
of meteorology that the carrying out of this proposal will be well worth 
while, not only from a scientific standpoint but also from the standpoint 
of service to the general public. 

The preparation of the data for charting and the printing or lithograph- 
ing of the charts for American use could best be done by the U. S. 
Weather Bureau, but to do this, additional funds must be provided 
through congressional appropriation. 

WORLD AEROLCX5Y 
By Wnxis Ray Gbbgg 

Aerology may be very simply defined as '*the study of the free air";^ 
world aerology, as an extension of that study to all parts of the world. 
By this we mean not only the continental areas, but the seas as well ; and 
not merely sections of a hemisphere, but from pole to pole. It is our 
'purpose to review very briefly ( 1 ) what has been and what is being done 
toward this end ; (2) more particularly, to outline what can at once and 
also what should later from time to time be undertaken. 

PAST AND PRESENT 

Methods, — ^As early as the middle of the 18th century kites were used, 
by William Wilson at Glasgow University and by Benjamin Franklin at 
Philadelphia, in making free-air observations. Others followed their ex- 
ample, with more or less success, but it was not until about 1890 that the 
kite came into general use for this purpose. 

So far as known, the first manned balloon ascent in the interests of 
science was made by Robertson and Lhoest in 1803. During the next 75 
years much interesting information as to free-air conditions was obtained 
by means of numerous similar ascents, among the most notable of which 
were the classic voyages of Glaisher, Flammarion, de Fonvielle and 
Tissandier.' Unlike the kite, however, the manned balloon has in recent 
years suffered a decline as a means of aerological exploration, because of 
the large expense involved and the impossibility of providing satisfactory 
exposure of the instruments. Although the observations made by these 
two methods were extremely interesting, yet prior to 1890 they 3delded 
comparatively little of value, owing to their fragmentary character and 
none too great accuracy. 

' See "Meteorological Glossary," British Meteorological Office, M. O. 225 ii, 1918, 
p. 16. London. 
' "Travels in the Air," edited by James Glaisher, F. R. S., Philadelphia, 1871. 



42 METEOROLOGY 

Since 1890 rapid strides have been made. The kite has been developed 
from a mere toy into a very efficient means of exploration. With it 
heights slightly exceeding 7 kilometers have been reached, although the 
average daily height is a little under 3 kilometers. Recording instruments 
carried by these kites furnish information as to pressure, temperature, 
humidity and wind at various heights and their changes from day to day, 
season to season, and under various types of weather at the earth's surface. 
Since the kite can be flown only when there is appreciable air movement, 
its use has in some instances been supplemented by that of a small captive 
balloon, and thus we have some records in calm weather. Generally 
speaking, however, the captive balloon has proved to be rather unsatis- 
factory and its use has been largely discontinued. 

For exploring the air to greater heights than can be reached with kites, 
so-called "sounding" balloons are used. Made of pure rubber, filled 
with hydrogen and carrying self-recording instruments, these balloons 
have given us information of great interest and value to heights of 
30 kilometers or more. Smaller, so-called "pilot" balloons, because of 
their comparative cheapness and convenience in handling, have in recent 
years come into general use for observing wind direction and speed. On 
clear days, when the wind is not too strong, these balloons can be fol- 
lowed by means of theodolites to heights well above 10 kilometers. 

All of these methods have been rather extensively employed in Europe, 
particularly in England, France and Germany, and in the central and 
eastern portions of the United States. Some of them have been used to a 
limited extent also in Canada, Australia, Java and Argentina, as well as 
on a few expeditions of short duration to different parts of the Atlantic 
Ocean. In addition, there should be mentioned the great mass of cloud 
observations, some of which, particularly those during the International 
Campaign of 1896-97, were accurately and systematically made by means 
of nephoscopes and theodolites and furnished information, not only as to 
the heights and other characteristics of the clouds themselves, but also as 
to wind conditions at various levels. 

Results. — Although a considerable amount of data has been gathered by 
the methods above outlined, it must be confessed that we know even yet 
comparatively little with reference to what is going on in the atmosphere 
above the earth's surface. The general state of our knowledge can be 
briefly summarized as follows : 

(a) For parts of Europe and the United States we have well estab- 
lished average monthly, seasonal and annual values of all the meteoro- 
logical elements from the surface to about the 5-kilometer level. Pressure 
of course always diminishes with altitude ; temperature and humidity do 
so on the average, except that in the north-central portions of the United 
States there is a temperature inversion in the lower levels during the 
winter months; wind velocity increases, sharply in the lowest half kilo- 
meter, more gradually above that height ; and wind direction is in the mean 
very nearly westerly at all levels, except in the southern part of the United 
States, where, during the sununer, it is south to east near the surface. 



METEOROLOGY 43 

(b) Of conditions between 5 and 25 to 30 kilometers we have rather 
limited information. We know that the temperature continues to diminish 
at a fairly uniform rate until a height of 8 to 18 kilometers is reached — 
this height varying with latitude, season, and sea-level pressure ; above this 
limiting height the temperature ceases to diminish and in fact has a 
tendency to increase to some extent, at any rate during the summer half 
of the year. The boundary plane between the lower region of temperature 
decrease, known as the troposphere, and the upper region of little tempera- 
ture change, known as the stratosphere, is in general well defined. Clouds 
do not occur in the stratosphere and winds generally have lower speeds 
here than in the troposphere. There is some evidence that at still greater 
heights wind direction changes from westerly to easterly, but data on 
this point are not conclusive. Other characteristics of the stratosphere 
are the lower temperature and greater height of its base in low than in 
high latitudes and during falling than during rising air pressure at the 
earth's surface; also, its greater height in summer than in winter. 

(c) Of the relations found to exist between surface weather and free- 
air conditions, perhaps none is more significant than that between surface 
temperature distribution and winds in the upper levels. As is well known, 
the winds at and very near the surface conform quite closely to the surface 
pressure gradient, but at greater heights they often depart widely from it. 
If the temperature is fairly uniform over wide areas, the free-air winds 
are very nearly parallel to the surface isobars, and show that anti-cyclones 
and cyclones extend as such to great heights. If, on the other hand, the 
latitudinal temperature gradients are steep at the surface and also, though 
to a less extent, in the higher levels, then the surface pressure systems 
lose their identity at a very low altitude, the isobars opening out on the 
north side of cyclones and on the south side of anti-cyclones, and the 
winds veering or backing from those at the surface in conformity with 
the altered pressure distribution at the higher levels. This relation of 
free-air winds to surface temperature distribution has not thus far been 
accorded the attention it deserves. With the development of aviation and 
the resulting demand for accurate free-air wind forecasts, the significance 
of this relation must necessarily receive increasing recognition. 

The foregoing summary is very sketchy and incomplete, but it will 
serve as a basis for the consideration of problems which must be attacked 
in the future, if real progress is to be made. 

THE FUTURE 

The present age, to a greater extent than any in the past, may be called 
an "age of projects." More and more mankind is giving heed to Emer- 
son's exhortation, ''Hitch your wagon to a star," and perhaps this is an 
especially appropriate motto for the aerologist to adopt as his own. Of 
the many ambitious plans that we read and hear about, some undoubtedly 
will yield negative results only, but it is equally certain that others will 
contribute very materially to human welfare. And it is better that some 



44 METBOROLOGY 

should fail than that none should be tried. The projects to be presented 
here are not visionary, but on the other hand very practical ones, and for 
the most part they are not difficult to carry out. They will be stated in 
the order in which it is believed they can be put into execution. 

1. Further study of data already accumulated, — ^There is much mate- 
rial now available that has not been sununarized and studied in detail or 
properly applied to the problems of aviation and forecasting, and to the 
solution of perplexing questions relative to the larger features of atmos- 
pheric circulation. One of the first things to be undertaken is the prepa- 
ration of such a summary. Very few men, outside of the government 
services, are giving the subject any thought. Those in the government 
services can devote comparatively little time to it, because of other more 
pressing duties. There are needed at once for this purpose half a dozen 
well-trained men (well trained both in theory and in field experience) 
who can give all of their time to this subject for a period of 3 or 4 years. 
This, then, is a comparatively simple project — one requiring only a small 
outlay of funds, but giving results of immense value. 

2. Development of new methods of observation, — As already stated, 
nearly all observing at the present time is done with nephoscopes, kites, 
pilot and sounding balloons. All of these methods have well-known limi- 
tations, but should be continued. There should be added, if possible, 
observations with kite balloons and airplanes. Kite balloons, although 
more expensive than kites and pilot balloons, would furnish data of 
correspondingly greater value, since they could be used with greater 
regularity, irrespective of weather conditions. Indeed, their use would 
be limited only by very high winds, and records could thus be obtained 
under conditions unfavorable for kites ; in other words, by combining the 
two methods, the atmosphere could be explored up to 3 kilometers prac- 
tically every day in the year. Like kites, their use would be restricted to 
regions not frequented by airplanes, because of the danger of fouling with 
the cable. Their use would be further restricted to places where hydrogen 
could be obtained. These limitations, however, are no more serious than 
others under which we now labor and can be overcome at comparatively 
small expense, when we consider the great value of the results obtained. 

Development of suitable apparatus for use in airplanes should be pushed 
vigorously. As aviation expands, there will necessarily be a large number 
of places at which regular daily flights will be made at and above the fields 
for purposes of testing the machines and the training of pilots. Obser- 
vations during these flights would add little expense and would provide 
information not otherwise obtainable, such as the thickness of cloud 
layers, etc. Work along this line has been done in England and France, 
but thus far to no great extent in this country, because of inadequate 
appropriations. It will be taken up as soon as funds for the purpose are 
made available. 

3. Extension of observation stations to all parts of the world. — This 
must be done through international cooperation, but the United States can 



METEOROLOGY 



45 



make a good start by more completely covering its own territory, includ- 
ing Alaska, the Hawaiian and Philippine Islands, etc. In making such 
an extensi(Mi, and a further extension later by all other countries, two 
separate and distinct purposes are to be served: (a) the furnishing of 
current information of immediate practical value to aviators; (b) the 



m^-^ ^ 


^ir^PS^B^SMy^ 




s ^ 


fC'v^^^^^f^'* 




-i 


K^K* 




.. y 


'0 ' 3L 


Z-. 


-/r~-s. j^^"^ ' 


k 




1 ^ ^ -1 





Fig. 4. Average summer values of pressure, temperature, density and resultant wind 

at the 3-kilometer level 



collection of statistical information required to explain the physical causes 
of various phenomena and, as a necessary consequence, to increase the 
accuracy of weather forecasting. For the first purpose it is sufficient to 
establish observii^ stations having comparativdy simple equipment, by 
means of which the atmosphere may be explored to moderate heights only. 
It 19 not essential that temperature and humidity be observed, but it is 
essential that frequent observations be made of wind, cloudiness and visi- 



46 METBOROLOGY 

bility, these being the factors of vital interest to aviators. For the second 
purpose a much more comprehensive prc^^m is necessary. We should 
have accurate values of temperature and moisture as well as of wind. 
Observations should extend to as great heights and be as nearly continu- 
ous as possible, in order that we may know the diurnal and annual varia- 
tions throt^hout the troposphere and much of the stratosphere; the 
characteristics of the atmosphere under different types of surface pressure 
and temperature distribution ; and latitudinal and longitudinal variations. 
It is absolutely necessary that these data be collected and carefully studied. 
Otherwise we shall continue to be bombarded by theories and» worse still, 
by sweeping conclusions which can hardly stand the test of further light 
on the subject, but which (and this is the unfortunate feature), being 
advanced by men of recognized standing, find their way into textbooks as 
facts and thus start the student upon an entirely wrong track. As in all 
other matters, so in meteorology it is regrettably true that ''a little learning 
is a dangerous thing." Specific references need not be made, but it may 
be remarked that in the past year or so there have been some particularly 
glaring instances of the promulgation of theories, based upon incomplete 
data, and of the more or less universal acceptance of those theories. 

As examples of the kind of information needed, figures 4 and 5 are 
shown. They are based upon all observations thus far made with kites 
in this country, and give respectively average summer and winter values 
of' pressure, temperature, density and resultant wind at the 3-kil<mieter 
level. These and similar charts for other levels, also charts showing 
relative humidity and vapor pressure, form part of a summary now in 
preparation, to be known as "An Aerological Survey of the United 
States." Some of the more prominent features shown in figures 4 and 5 
are: (a) the close relation between the latitudinal pressure and tempera- 
ture gradients; (b) the small latitudinal density gradient, owing to the 
counterbalancing effects of pressure and temperature, i. e., density varies 
directly with pressure, inversely with temperature; (c) the slight south- 
ward trend of lines of equal values of these elements from the interior to 
the eastern portions of the country; (d) the close agreement between 
computed and observed resultant winds in the winter season. The less 
satisfactory agreement in sunmier is due to the greater frequency of days 
with winds too light for kite flying (another argument for the use of kite 
balloons and airplanes) ; and (e) the small latitudinal difference in resul- 
tant wind speeds, due to the fact that these vary directly with the pressure 
gradient, but inversely with the sine of the latitude. 

It is probably not a coincidence, but rather a matter of considerable 
significance, that the average movement of cyclones in the United States 
during the winter, as determined by Bowie and Weightman, is 13.4 m.p.s.^ 
— ^a value in striking agreement with the resultant wind shown in figure 5. 
The agreement is less close in summer, apparently indicating that cyclones 

*■ Types of storms of the United States and their average movements. Monthly 
Weather Review, Sui>plement no. 1, p. 8. 



METBOROLOGY 



47 



extend to a greater height in that season than in winter, and this, as 
already pointed out, is undoubtedly the case. 

These figures, however, are not shown with the view of discussing them 
as such, but rather with that of indicating how important it is that we 
obtain similar information for all other parts of the world — ^the sea as 








"^ (^ 


mi 


y""^'^'^ (\ 


JPi^ 






^^^ 


■* "^"S" 




r a^ii^ 




h^'*" 


f^'^'^'^f 




\ SVfHr£Mt 

\aeMSfrr /t§/bm 






m 













Fig. 5. Average winter values of pressure, temperature, density and resultant wind 

at the 3-kilonieter level. 



well as the land. Obviously, it is impossible to carry out this program 
at once in its entirety. We must therefore start with the most pressing 
needs, as follows : 

It is well known that the type of pressure distribution prevailing in the 
region of Alaska exercises a dominating influence on the weather of the 
United States. Similar relations are found in other parts of the northern 



« METEOROLOGY 

hemisphere and emphasize the importance of having a network of stations* 
observations from which would make possible the construction of world 
weather maps — ^a subject which has already been presented by Major 
Bowie (see page 36). As indicated by him, such observations would 
enable the forecaster to follow from day to day the eastward march of 
the so-called '^polar front." ^ There should be a string of stations as far 
north as possible and, in the southern hemisphere, another as far south as 
possible. Some of these stations at least should be provided with equip* 
ment for free-air exploration, this exploration to include accurate obser- 
vations of wind and clouds by means of theodolites and nephoscopes. A 
few should, in addition, be equipped for makii^^ measurements of tem- 
perature and moisture, as well as wind, to great heights. These few would 
necessarily have to be not too far removed from sources of supply, but the 
others, if equipped with radio, could well be located as far north as living 
conditions would permit. 

It has been said that definite meteorological laws will be established 
only from observations made at sea. These are difficult, perhaps impos- 
sible at the present time, to make, but there are numerous small islands 
where the influences of the land upon the atmosphere are negligible. Data 
of inestimable value can be obtained by establishing free-air observing 
stations in Bermuda, the West Indies, the Azores and the islands of the 
Pacific ; also in Central America, where continental effects would be small. 
We know none too much about the prevailing westerlies, but our knowl- 
edge of them is voluminous compared to that of the antitrades. Such a 
network of stations as I have indicated, especially if operated for a con- 
siderable period of time and supplemented by observations from ships at 
sea, would provide the information now lacldng and, in addition, would 
solve the much discussed and still unsettled questions of the exdiange of 
air between the equator and the poles, the movements of hurricanes, etc. 

Aside from the settlement of these theoretical questions, and perhaps 
more important, is the value of such observations for daily use in fore- 
casting. With the development of radio communication, reports from 
these stations should be capable of speedy transmission to forecast centers, 
where they could be charted on upper-air maps, supplementary to the 
world weather maps, already discussed. Their value to aviators need 
not be argued. Can anyone doubt their even greater value, with further 
study, to the forecasting, not only of day-to-day weather, but also of week- 
to-week, month-to-month and possibly year-to-year changes in weather? 

^ See V. Bjerknes. The meteorology of the temperate zone and the general atmos- 
pheric drculation. Nature, June 24, 1920, S22-524. 



METEOROLOGY 49 

WORLD DIGEST OF METEOROLOGICAL DATA 

By W. J. HUMPHBBYS 

Meteorological data are gathered f or, and serve, many purposes : 

They are abundantly used in forecasting the weather of the morrow, 
but obviously used only once, and hence for this purpose need not be 
recorded. 

They also are collected in the course of special studies, but the comple- 
tion of each investigation renders useless the preservation of the particular 
material treated. It is the generalization — ^the law — ^that counts, and not 
the isolated values from which it happened to be deduced. 

Finally, they are essential to many studies of interrelations between 
meteorological elements; to a knowledge of the relation of the weather 
in one part of the world to that occurring either previously, simultaneously, 
or subsequently, in others ; and to all accurate knowledge of climates and 
their changes. For each of these purposes it is necessary that meteoro- 
logical data be indefinitely accumulated, and equally necessary that they 
be put in manageable form and made widely available. 

Now, although fully three-fourths of the surface of the earth is a 
meteorological blank, the mass of data already accumulated from the 
remaining one-fourth is so vast and heterogeneous as to be beyond the 
power of any individual to analyze and study in detail. Furthermore, 
even approximately complete sets of these data have been assembled in 
very few places. Hence much of the information contained in this 
meteorological material certainly is not only unknown, but even beyond 
the power of individual effort to know. 

Therefore it is suggested that a comprehensive digest of all existing 
meteorological data be made and published. A possible way of accom- 
plishing this great labor is as follows : 

1. Let the data to be published (monthly and annual normals and 
departures therefrom, special phenomena, and what not), the units to be 
used, the form of publication, and all other details of this kind, be agreed 
to internationally. 

2. Let each country furnish the digest of its own data. 

3. Let the digest for each country consist of the individual digests for, 
and made at, its several meteorological stations. 

4. Let some one agency, supplied with adequate funds and personnel, 
be charged with the duty of assembling sporadic data from countries that 
have no official meteorological organization ; and with the further impor- 
tant duty of editing the entire work. 

In this way the proposed vast labor would be divided up between sev- 
eral countries, and further subdivided among many individuals in each 
country, and the product of the combined effort of the many workers — 
the digest of all the world's meteorological data — soon made available to 
every institution that needs it and to every individual who wishes to 
study it. 



50 MBTBOROLOGY 

There then could be students of world meteorological data» and would 
be ; now there is none — and can not be. 

It will be recognized of course that the plea here is for a greater 
"Reseau Mondial/' one covering a larger number of meteorological ele- 
ments than does that splendid publication, and also extending back to the 
banning of meteorological observations. It would both include and 
supplement the data contained in the present Reseau Mondial, but would 
not take the latter's place as a convenient annual summary of the more 
important elements of the world's weather at selected places. 



GENERAL ADOPTION OF THE CENTESIMAL SYSTEM OF 

ANGULAR MEASUREMENT— WITH APPLICATION 

TO ANEMOMETERS AND NEPHOSCOPES 

By ALBXANim McAon 



Reviewing an article on "Uniformity in Aerographic Notation/' ^ Sir 
Napier Shaw ' calls attention to the common usage of the capital letters 
N.E.S.W. for wind directions, and the established usage in Physics of 
N for Avogadro's constant, E for Energy, S for Entropy and W for 
internal work. 

The criticism is constructive and suggestive. The question arises : Is it 
not desirable to follow the lead of navigator and magnetidan and use 
degrees instead of letters to indicate direction of air flow? There are 
some distinct gains from such a usage for the aerographer or chart maker 
of the winds. Official weather bureaus record direction on a 45-degree 
basis ; that is, eight directions are given. It has long been felt that such 
records were not sufficiently detailed. Precision, detail and convenience 
are gained by the use of the degree. 

There is no mechanical difficulty in getting continuous records of wind 
direction for the entire circle. Many forms of anemoscope give such 
records. Figure 6 gives such a record sheet based on one used at Blue 
Hill for 35 years. The eight cardinal directions are noted ; but instead of 
32 points of the compass, as heretofore, the intervals are at 10 degrees, 
and thus 36 divisional lines appear instead of the old compass point 11.25. 
For convenience in computation there is also introduced Greenwich Mean 
Civil Time, beginnii^ at an hour appropriate for changing records on 
this coast, noon 75th meridian time being 17 hours Greenwich time. The 
sheet, however, is adaptable to any station meridian time, by inserting 
the proper hour in the S.M.T. column. If, however, the centesimal system 
is to be used, the number of divisional lines is increased to 40, and since 
there are 400 grads in the circle, each division represents 10 grads or 
9 degrees. 

* H. A. 83-4, pp. 16^180. 

* Nature, Nov. 4, 1919. 



MBTBOROLOGY 



51 






WJND DiRecTION CHART 

AiH tTATlON AT 



4^ 



: 



at 



r 



S^ 

Mi* 



mtjii 



wm 



r^ 






i^ 



L^ 



sac. 



A 



k^ 




aATf 



m 



kd! 



^ 



'J jaL 






<M ; rn nri; r 

/« Ji0 ,30 fpA €0 f tp§a . 4 ^ 



Ml 



Liii 




7 






4 



I 



w 



:: 



iiiiiM'i Iqi >'^i?''«^ fnViV>i 111111 



llXlil 




[■P f» *• « •* ''^ * 



1^ 



hJL 



fifi 



I II 1,1.1. 1.1 ! 



i-l 



irr 



n 

u 



tfea 



/i 



J3L 



n 



-£l 



.a 



J3_ 



a 



J»L 



Ct.pt.T- MiS»M«n<w 
•.lft.7 «7WritfW -rime 



Fig. 6. Wind-direction chart. 



METBOROLOGY 



By the use of such charts, the words westerly, easterly, and other like 
terms disappear and the flow is more definitely described. Wind vanes, 
unfortunately, do not fly with the wind, but against the wind, the arrow- 
head pointing into the wind. On the other hand, in all charts of air flow, 
the arrows fly with the stream. 







Fig. 7. Wind protractor for use with McAdie nephoscope. 

The direction of flow is read to the right, starting from zero, at the 
north ; and thus an east wind is defihitely recorded as 100 grads (or 90 
degrees), and a south wind as 200 grads (or 180). 

The value of the natural sine of 100 gp^ds is 1. The following abridged 
table gives the sines, cosines, tangents and cotangents of every 10 grads : 



METEOROLOGY 53 

grads sine cosine tangent cotangent 

100... 1.00000.. 0.0000 oe 0.0000 

90... .9877... 0.1546.... 6.3138.... 0.1584 

80... .9511... 0.3090.... 3.0777.... 0.3249 

70... .8910... 0.4540.... 1.9626.... 0.5095 

60... .8090... 0.5878 1.3764 0.7265 

50... .7071... 0.7071.... 1.0000.... 1.0000 

40... .5878... 0.8090.... 0.7265.... 1.3764 

30... .4540... 0.8910.... 0.5095.... 1.9626 

20... .3090... 0.9511.... 0.3249.... 3.0777 

10... .1546... 0.9877.... 0.1584.... 6.3138 

0... .0000... 1.0000.... 0.0000 oc 

During the World War those of us who were engaged in aerogra^hic 
work in France found it necessary to use the centesimal system. Since 
the war» the method has been adopted by the Scandinavian countries. 

In nepho$copic determinations, the method has been used with success 
at Blue Hill. A comparative dial of the compass, the magnetic and the 
centesimal values is given in figure 7. 



A SINE GALVANOMETER FOR DETERMINING IN ABSOLUTE 

MEASURE THE HORIZONTAL INTENSITY OF 

THE EARTH'S MAGNETIC FIELD ^ 

By S. J. Baknrt 

A brief historical statement was made with reference to the measure- 
ment of the horizontal intensity of the earth's magnetic field by electrical 
methods, and a general description of sine and tangent galvanometers was 
given, with the suggestion of an improvement in the latter. Then fol- 
lowed a detailed description of a new sine galvanometer, constructed, with 
certain exceptions mentioned below, in the workshop of the Depart- 
ment of Terrestrial Magnetism. 

The base of the instrument, including the tripod, circles, etc., was taken 
from one of Wild's theodolites, constructed by Edelmann, and was much 
improved by the substitution of non-magnetic parts for parts too mag- 
netic, and by the substitution of electrical illumination of the precision 
circle for daylight illumination by mirrors. 

The magnetometer-box is of pure copper, the damping being chiefly 
electro-magnetic. The magnet-mirror is a fine disc of chrome steel with 
optically flat and parallel surfaces, being in fact one of the gages made 
by the Bureau of Standards. The torsion tube and head are similar to 
those of the C. I. W. magnetometers. A suspension of phosphor-bronze 
strip with torsional constant about 0.001 is generally used. The telescope 
is small but powerful ; the scale is ruled to thirds of mm., on white pyralin, 
with all necessary adjustments. The period of the magnet and the damp- 
ing, which is adjustable, are such that readings require only a few 
seconds. 

The arrangement of coils is approximately that due to Helmholtz. The 
spool was machined from white Carrara marble impregnated with parafiin 
at a temperature near its boiling point. The coils were wound under 
tension in a single layer in spiral grooves cut with a carbon diamond tool. 
The wire is pure copper, especially prepared in the research laboratory 
of the General Electric Co. Each coil is wound in two halves and contains 
10 turns with a diameter of approximately 30 cm. and a pitch of approxi- 
mately 2 mm. The two halves start from the same horizontal plane 180 
degrees apart, so that the distance between centers of adjacent wires is 
approximately 1 mm. The axial distance between the centers of the 
two coils, or the distance between corresponding turns of the spirals, is 
approximately 15 cm. The insulation resistance between adjacent wires is 
very high. 

The methods of measuring the diameters and axial distances of the 
spirals were briefly described and some of the results were given in tables 

^Abstract of the report presented before the American Geophysical Union, Wash- 
ington, D. C, April 18, 1921. 

54 



TERRESTRIAL MAGNETISM AND ELECTRICITY 55 

and curves, projected on the screen. The magnetic tests, of three kinds, 
proving the materials to be satisfactory, were also described. 

The theory of the instrument, the method of using it, and the calcula- 
tion of the error in the constant of the coils due to construction, as well 
as of the other errors introduced in the measurement of the horizontal 
intensity, were briefly presented. 

It was shown that the errors in reading the circle and the telescope scale 
when sufficiently large angles are used, and the error in the constant of 
the coil, were quite negligible ; and that the only other error necessary to 
consider, viz, that introduced in the measurement of the current travers- 
ing the coils, can also be made entirely negligible. In consequence, the 
horizontal intensity of the earth's magnetic field can be determined with 
an error less than 1 part in 10,000, which more than fulfills all necessary 
requirements. 

The instrumental work, done in the shop of the Department, chiefly by 
Mr. G. H. Jung, instrument-maker, is highly satisfactory. 

The report was closed with acknowledgments.^ 

Department of Terrestrial Magnetism, 

Cam^e Institution of Washington. 

ACTIVITY OF THE EARTH'S MAGNETISM IN 1915 

By D. L. Hazabd 

At the meeting of the International Commission for Terrestrial Mag- 
netism held at Innsbruck in 1905 a resolution was adopted recommending 
that magnetic observatories classify each day according to its magnetic 
character as quiet, moderately disturbed, or severely disturbed, using the 
notation 0, 1, and 2 for this purpose. This recommendation has been 
adopted by different observatories, one after another, so that now nearly 
all of the prominent observatories are sending quarterly reports of the 
magnetic character of days to the Netherlands Meteorological Institute 
and that institution is publishing them, thus making the data available for 
all. While this method of characterization is necessarily rough and influ- 
enced by the personal equation of the observer, yet the mean of a large 
number of estimations (between 35 and 40 at the present time) gives a 
very good idea of the relative magnetic condition of the whole earth from 
day to day. It does not, however, give an absolute measure of the daily 
fluctuations of the earth's magnetism nor does it permit a comparison of 
conditions in different parts of the earth. 

In order to determine quantitatively as well as qualitatively the varia- 

* Since the presentation of this report, the constant of the coil has been redeter- 
mined by the use of many additional linear measurements, and two series of simul- 
taneous determinations of the horizontal intensity with the sine galvanometer and the 
C. I. W. standard magnetometer No. 3 have been made, Messrs. Fleming. Fisk, 
Peters, Ives, and Bamett participating. The results obtained showed a satisfactory 
agreement between the two different types of instrument A complete account of 
the instrument is given in Vol. IV of the "Researches of the Department of Ter- 
restrial Magnetism." 



56 TERRESTRIAL MAGNETISM AND ELECTRICITY 

bility of the earth's magnetism as a whole, the late Doctor Bidlingmaier 
devised a method which takes as a measure of the activity of the earth's 
magnetism its departure from moment to moment from its normal or 
undisturbed condition. As we have no means of determining as yet what 
the normal magnetic condition of the earth is, he adopted as the basis for 
his computations the mean value for the period under discussion ; that is, 
the activity for a day is based on the momentary departures from the mean 
value for the day. He found that in determining the activity for the day 
with reference to the mean, the computation could be separated into two 
parts, first the departures of the hourly mean from the mean for the day, 
and second the departures of the individual values in each hour from the 
mean value for that hour. If it later should become desirable to refer 
to a base value other than the daily mean it would only be necessary to 
add a third term, depending on the difference between the daily means 
and the new base value. In each step the mean of the squares of the 
departures from the base value is computed and this quantity expressed 
in y' must be divided by 8ir to get the activity expressed in terms of the 
unit 10"" erg/cm' ; that is, the energy per unit volume. 

The regular observatory tabulations contain the data for computing the 
first part provided the mean ordinate for each hour is tabulated, as is now 
the established practice. Computation of the second part would ordinarily 
involve the reading of ordinates at frequent intervals for each hour and 
the computation of the mean of the squares of the differences from the 
mean value for the hour, this being the so-called hour-integral used in 
Bidlingmaier's formula in determining that portion of the activity. The 
amount of work involved would, of course, be prohibitive and he accord- 
ingly simplified the process by reading the ordinates for a limited number 
of hours and using the relation between the hour-integral and the hourly 
range as a basis for determining the hour-integral for the remaining hours 
from the hourly range. When the results were plotted with amplitude 
(half range) as abscissa and hour-integral as ordinate, it was found that 
the line joining the plotted points formed a smooth curve of parabolic 
form. While it was found that the values of hour-integral corresponding 
to a given hourly range differed considerably among themselves, as would 
naturally be the case because of the varying character of the fluctuation 
within the period of an hour, yet it was believed that for most purposes, 
where the results would be combined to obtain mean values, the relation 
between hourly range and hour-integral derived from a limited number 
of hours could safely be used in determining the hour-integral for a long 
period, as for a year. 

The parabolic form of the curve representing the relation between 
amplitude and hour-integral suggested the probability that a linear relation 
would be found to exist between the square of the amplitude (or range) 
and the hour-integral. In fact, this must necessarily be the case if the 
value of activity is to be independent of the sensitivity of the instruments. 

At the request of the International Commission for Terrestrial Mag- 



TERRESTRIAL MAGNETISM AND ELECTRICITY 57 

netism a number of observatories undertook to compute the activity of 
the earth's magnetism according to this method for each day of the year 
1915, the Coast and Geodetic Survey carrying out the work for its mag- 
netic observatory at Cheltenham, Maryland. It was suggested by the 
International Commission that other observatories might safely accept the 
relation between hourly range and hour-integral as determined by Bid- 
lingmaier for Wilhelmshaven for the year 1911. It was thought best, 
however, by several observatories, to re-determine this relation in order to 
be assured that it did not change from place to place. The results show 
that while for Wilhelmshaven the hour-integral was equal to 11^4 percent 
of the square of the range, for Cheltenham the factor was 10 percent 
and for Seddin, near Potsdam, 8^ percent, and an investigation by Chree, 
which included the study of the records of the British Antarctic Expedi- 
tion, showed that while for ordinary latitudes the variation in the factor 
was not great, conditions were quite different in very high magnetic 
latitudes. 

When the preparation of this paper was undertaken it was expected 
that it would be possible to compare the results from several observa- 
tories, but it was found that only the Seddin results, in addition to those 
for Cheltenham, were available in printed form. 

The geographic positions and mean values of the magnetic elements 
for 1915 for these two stations are as follows: 

Observatory Cheltenham Seddin < 

Latitude 38** 44' N 52^ 23' N 

Longitude 76 50W 13 04 E 

Declination 6 04W 8 17W 

Dip 70 47 N 66 25 N 

Horizontal intensity 19417y 18726y 

Vertical intensity 55694/ 4289&y 

Total intensity 58982y 46806y 

It will be seen that the two observatories differ very nearly 90® in 
longitude, and while Seddin is much farther north than Cheltenham, the 
magnetic dip and intensity are much greater for Cheltenham, the latter 
station being nearer the magnetic pole. 

The activity has been computed for each hour for D, H, and Z at 
Cheltenham and for X, Y, and Z at Seddin, and these three are combined 
to get the total activity. The quantities published are the mean value for 
each day of the year and the hourly means for each month. 

In discussing the results of this method of determining the activity three 
things must be kept in mind. First, since the activity is based on the 
square of the departure from the mean value, a day of very large disturb- 
ance will have an overpowering effect on mean values in which it enters. 
For example, the activity at Cheltenham for June 17 was 1477 and the 
total for the other 29 days was only 666. Second, Bidlingmaier's concep- 
tion of activity is different from the usual idea of activity as represented 



58 TERRESTRIAL MAGNETISM AND ELECTRICITY 

by a magnetic disturbance. In the latter case we think only of abnormal 
variations, whereas he includes all variations, whether systematic (as 
diurnal variation) or abnormal. Third, as part of the variation of the 
earth's magnetism is a function of local mean time and part is a function 
of absolute time, the results for different observatories are not strictly 
homogeneous. For this reason a more satisfactory agreement between 
the results for different places may be expected if only that part of the 
activity is considered which is derived from the hour*integral, as this is 
to a greater extent independent of local mean time. Even then, how- 
ever, there is some lack of homogeneity, as for example, in the case 
of the Seddin tabulations the day begins at Greenwich midnight, whereas 
for Cheltenham it b^ns at 5^ G.M.T. 

The portion of the activity derived from the hour-int^ral is much 
smaller than the part depending on the differences between the mean 
hourly values and the daily mean, only about one-eighth as great on the 
average for all days and only one-twenty-fifth for the less disturbed days. 
The fact that the normal diurnal-variation is such a predominant factor 
in the total activity as derived by Bidlingmaier's method raises the ques- 
tion whether results of greater value would not be obtained if the diurnal 
variation was eliminated, at least in part, in computing the activity. 

A comparison of the daily mean values of total activity for the two 
observatories for 1915 shows a general agreement, but with considerable 
difference in detail, largely because of the third point referred to above. 
The total activity is on the average about 15 percent greater for Chelten- 
ham than for Seddin, as was to be expected on account of its higher 
magnetic latitude, but for many days and even for some monthly means 
the Seddin values are greater. 

If only the hour-integral activity is used in the comparison, the agree- 
ment is much closer, and when the results are smoothed out by taking 
five-day means the plotted curves for the two places are almost identical 
in phase. The agreement is almost as good with the international char- 
acter numbers, both in phase and relative amplitude, and speaks well for 
that simple method of determining the degree of disturbance. 

A comparison of the monthly means with the relative sun-spot numbers 
for the same periods shows little evidence of systematic agreement, thus, 
as pointed out by Schmidt,^ confirming former experience in comparing 
these numbers with terrestrial phenomena. In this case the lack of agree- 
ment is no doubt partly due to the exaggerated effect on the mean activity 
for a month of a single day of great disturbance. 

As to the diurnal variation of the total activity, the predominant feature 
is a maximum occurring about noon local mean time. At Cheltenham 
this feature is modified in the months May to August to form a two- 
peaked stunmit with maxima about 10^ and 14'^ and a considerable depres- 
sion between. There is little variation in activity during the night hours. 
The range of activity is greater in summer than in winter, though, as 

^ Terrestrial Magnetism, Sept, 1920. 



TERRESTRIAL MAGNETISM AND ELECTRICITY 59 

already pointed out, the effect of a single day of great disturbance is 
overpowering. The above characteristics can be traced at once to the 
features of the diurnal variation of the magnetic elements, the two max- 
ima at Cheltenham corresponding to the minimum horizontal intensity 
before noon and the maximum west declination after noon. 

If we consider only the hour-integral activity, we find very little evi- 
dence of system in its diurnal variation in the (Ufferent months, but there 
seems to be a tendency toward higher values toward the end of the 24 
hours. This is more pronounced for Seddin and corresponds to the dis- 
tribution of disturbed hours arrived at directly. The effect of a few 
disturbed hours is so great, however, that it is hardly safe to draw definite 
conclusions from the results of a single year. 

Schmidt discusses some other phases of the activity at Seddin in 1915, 
in the paper referred to above, but time does not permit going into the 
matter in greater detail here. He also makes some comparisons with the 
results of simpler methods of determining the activity. 

As a result of the activity computations for 1915, I am of the opinion, 
which is shared by Schmidt and Chree, that equally valuable results can 
be obtained by other methods that involve much less time and labor than 
Bidlingmaier's. His method gives undue weight to days of large disturb- 
ance in any combination of hourly values, and the introduction of the term 
depending principally on the diurnal variation of the earth's magnetism 
prevents a satisfactory comparison of results at different stations. 

Division of Terrestrial Magnetism, 

U. S. Coast and Geodetic Survey. 

ON MEASURES OF THE EARTH'S MAGNETIC AND ELEC- 
TRIC ACTIVITY AND CORRELATIONS 
WITH SOLAR ACTIVITY 

By Louis A. Bauer 

When attempting to find correlations between manifestations of the 
sun's activity and those of the earth's magnetic and electric activity, three 
points require immediate consideration : 

(1) What shall be taken as an adequate measure of the sun's activity 
with respect to such radiations and emanations as are likely to have 
an effect upon the magnetic and electric fields of the earth ? 

(2) What shall be taken as an adequate measure of the earth's mag- 
netic activity, or of the earth's electric activity? 

(3) What quantities shall be taken as defining the so-called normal or 
undisturbed condition of the earth's magnetic field, or of the earth's elec- 
tric field? 

With respect to the first question, we have at present at our disposal 
the sun-spot numbers, sun-spot areas, flocculi areas, prominences, f aculae, 
and solar-constant values. 

For measures of the earth's magnetic activity, as well as of its electric 



60 TERRESTRIAL MAGNETISM AND ELECTRICITY 

activity, we may use fluctuations in the magnetic and electric quantities, 
which are more or less periodic in their character, as, for example, the 
diurnal range or annual range of the magnetic and electric elements. But 
it is also found that during a magnetic storm and for some time after- 
wards, the earth's permanent magnetic state, as also possibly its electric 
state, has been affected. Thus, we have at our disposal both fluctuations 
about a mean value for a certain interval, and also change in that mean 
value for a given time. The selection of normal or undisturbed values of 
any measure taken may be based upon the international list of so-called 
magnetically-calm or electrically-calm days. Though it must not be over- 
looked that often the values of the magnetic and electric elements on such 
days are affected by a peculiar kind of disturbance. In brief it has been 
found that the magnetic or electric elements on a comparatively undis- 
turbed day are not necessarily normal values. Rather may the values be 
"normal" which lie intermediate between those for the "quiet" days and 
those for the days of moderate disturbance. 

Every analysis thus far undertaken of any particular magnetic fluctua- 
tion indicates that the observed effects are to be ascribed to at least two 
systems of forces : E, an external system consisting most probably of elec- 
tric currents in the upper regions of the atmosphere; and /, an internal 
system consisting of electric and magnetic systems below the earth's sur- 
face. The two systems E and / are not necessarily related as though / 
were the result of an inductive effect caused by the system £. The system 
/ would appear rather as a composite system, composed primarily of a 
direct effect and secondly of an indirect effect .which may be related to 
the fluctuating E system. Indications have also been found of the pres- 
ence of a third system, C, consisting of vertical electric currents which 
apparently pass through the earth's surface, either from the atmosphere 
or from some internal source. What we observe during a magnetic storm 
is the combined effect of the three systems, E, I, and C, and this important 
fact must be borne in mind in endeavoring to find correlations between 
solar activity and terrestrial activity. It may even happen, as apparently 
was the case on May 8, 1902, during the eruption of Mont Pelee, that we 
have a world-wide magnetic fluctuation of internal rather than external 
origin. Hence, were it feasible, a mathematical analysis should be imder- 
taken first of a magnetic disturbance in order that the effects coming from 
external sources may be separated from those to be related to internal 
ones. 

The question has also been raised, since at times a magnetic disturb- 
ance on the earth apparently precedes some striking manifestation of solar 

activity, whether there may not be also the possibility of a universe dis- 
turbance-system affecting both solar activity and planetary magnetic 
activity. 

As the combined result of my investigations to date, it is found that, in 
general, the most successful measure of solar activity, of special interest 
here, is a qtiantity indicative of the variability of sun-spottedness during a 



TERRESTRIAL MAGNETISM AND ELECTRICITY 61 

given period. For example, instead of taking the sun-spot numbers (N) 
direct for comparison with magnetic or electric fluctuations, the range 
(J?) in the sun-spot numbers per month, or the average departure (D) 
of the daily sun-spot numbers from the monthly mean, irrespective of 
sign, is taken. The R and D quantities are found to run closely parallel 
to one another; preference was finally given to the D-measure of solar 
activity as it utilizes all the sun-spot numbers {N) during a month, 
whereas, the /^-measure depends only on two numbers — ^the maximum and 
minimum sun-spot numbers of the month. The annual mean values of R 
and D are furthermore found to run closely parallel with the ^-numbers ; 
the monthly values of R and D, however, generally follow a decidedly 
different course from the iV-numbers and exhibit a closer relationship with 
the measures of the earth's magnetic, or its electric, activity than do the 
latter (the N's). Some of these relationships between solar activity, 
terrestrial magnetism, and terrestrial electricity (earth-currents, atmos- 
pheric electricity, and polar lights) are shown in figures 1 and 2 and are 
summarized below. 

The adopted measure of the earth's magnetic activity is a quantity, 
w = cHv, where H is the horizontal intensity of the earth's magnetic field 
at the observing station and v, the observed magnetic variation, or range 
of the magnetic fluctuation; € is a numerical factor. It may be shown 
theoretically that this value of zv, as a first approximation, is representa- 
tive of the energy-change which the earth's magnetic field experiences 
during a magnetic variation. 

Under certain assumptions it may also be shown that the R and the D 
measures of solar activity may be regarded, as a first approximation, as 
representii^ an energy-change experienced by the sun during a manifesta- 
tion of activity. 

Obtaining similarly, as just described for the sun-spot numbers, R and 
D measures of solar activity from the solar-constant values (£), which 
have been observed under the auspices of the Smithsonian Institution at 
Calama, Chile, during 1919 and 1920, it is found that these latter measures 
run much more closely parallel with the R and D measures derived from 
sun-spottedness than do the numbers E and N. 

Connections between sun-spot activity, disturbances of the earth's mag- 
netism, earth-currents, and polar lights have been worked out by various 
investigators. The present investigation shows that there is a fifth natural 
phenomenon — atmospheric electricity — ^by which an interesting and sug- 
gestive relationship with solar activity is exhibited. Owing to the many 
disturbances to which the atmospheric-electric elements are subject, as for 
example during cloudy and rainy weather, it has been more difficult to 
establish the existence of definite variations of the chief atmospheric- 
electric elements during the well-known sun-spot cycle of somewhat over 
11 years than in the case of magnetic effects, earth-currents, and polar 
lights. The new results found are based upon atmospheric-electric data 
obtained chiefly at four European observatories between 1898 and 1919, 



62 



TERRESTRIAL MAGNETISM AND ELECTRICITY 



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Fig. 1. Variations in solar activity, terrestrial magnetism, atmospheric 
electricity, and earth-currents during 1905-19^. 



TERRESTRIAL MAGNETISM AND ELBCTRICITV 



63 



the combined data in the case of the potential-gradient thus covering about 
two sun-spot cycles. Recent observations on board the Carnegie also indi- 
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a<:tivity was at a maximum. A half century ago Quetelet at Brussels and 





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Pig. 2. Variation of the electric-potential gradient and of its diurnal 
range during sun-spot cycle. (See also Fig. 1.) 

Wisclxzenus at St. Louis believed that they obtained some definite results 
showing a variation in the potential-gradient dependent upon sun-spotted- 
ness. Owing, however, to the uncertainty of results obtained by the in- 
strumental methods then in use and because of the necessity of thoroughly 
eliminating the numerous disturbances dependent upon meteorological 



64 TERRESTRIAL MAGNETISM AND ELECTRICITY 

condition*, these previous results have not been accepted, and so modern 
treatises on atmospheric electricity omit mention of any possible relation- 
ship between atmospheric electricity and solar activity. 

More complete publication of the results of the investigations here out- 
lined is made in the 1921 volume of the Journal of Terrestrial Magnetism 
and Atmospheric Electricity, pages 33-68 and 113-115. 

CHIEF RESULTS 

1. The earth's magnetic energy and average intensity of magnetization, 
as well as the strength of the normal electric currents circulating in the 
earth's crust, suffer a diminution during increased solar activity. The 
electric currents induced in the earth during periods of increased solar 
activity are in general reversed in direction to the normal currents, the 
strength of these superposed currents increasing with increased solar 
activity. 

2. The diurnal range of the strength of earth-currents, as in the case 
of the diurnal range of the earth's magnetic elements, increases with 
increased solar activity ; at time of maximum activity the range, as shown 
by the observations at the Observatorio del Ebro, Tortosa, Spain, during 
the period 1910-1919, was about 50 percent higher than at the time of 
minimum solar activity. 

3. The magnetic effect running a concomitant course with the solar- 
activity cycle is retarded, on the average, about one year so that there is 
a residual, or an acyclic, effect at the end of the cycle. The actual amount 
of retardation, in general, increases with intensity of the sun's activity 
or energy. This lag in the magnetic effect may be accounted for by the 
fact that the electric currents generated inside the earth during magnetic 
storms and magnetic variations continue for some time after the apparent 
cessation or diminution of solar activity, or after the period of the varia- 
tion experienced. The same lag is shown by polar-light frequencies at 
times of maximum solar activity. 

4. On fine-weather, or electrically-calm, days the atmospheric potential- 
gradient, or the deduced negative charge on the surface of the earth, 
increases with increased solar activity, the range in the variation between 
minimum and maximum solar activity being about 20 percent. The elec- 
tric conductivity of the atmosphere, on the other hand, shows but little, 
if any, systematic variation during the solar cycle. Accordingly, since 
the vertical conduction-current of atmospheric electricity is derived from 
the product of the potential-gradient and the electric conductivity, it is 
found that this vertical current also increases in strength with increased 
solar activity. It would thus appear that atmospheric electricity, like 
terrestrial magnetism, is controlled by cosmic factors. The results derived 
here may have an important bearing upon theories of atmospheric 

electricity. 

5. The diurnal range of the electric potential-gradient as deduced from 
the observations on the electrically-calm days, made at the Observatorio 



TERRESTRIAL MAGNETISM AND ELECTRICITY 65 

del Ebrp, Tortosa, Spain, 1910-1919, is found to increase with solar 
activity; the minimum occurred in 1911 and the maximum in 1917, 
whereas the sun-spot minimum occurred in 1912 and the maximum in 
1917. The range between minimum and maximum diurnal range is about 
25 percent. (It appears probable that the same fact just stated for the 
potential-gradient will also be found true for the vertical conduction- 
current.) Department of Terrestrial Magnetism, 

Carnegie Institution of Washington. 



THE PENETRATING RADIATION AND ITS BEARING UPON 

THE EARTH'S ELECTRIC FIELD ^ 

By W. F. G. Swann 

The paper was devoted largely to a description of certain investigations 
on the penetrating radiation in progress at the University of Minnesota, 
under the author's direction. It opened with a brief review of the status 
of our knowledge with regard to the penetrating radiation. 

In a hermetically sealed zinc vessel freed from radioactive air, ions are 
produced at a rate of about 8 or 9 per c.c. per second over the land. Ac- 
cording to the computations of A. S. Eve, the normal gamma-ray radiation 
from the atmosphere is capable of accounting for about 0.06 ion per c.c. 
per second, while that from the soil will account for 1.6 ion per c.c. per 
second, making in all 1.7 ions. On account of the secondary ionization 
resulting from electrons emitted from the walls of the vessel by the pri- 
mary radiation, this vahie becomes increased to about 2.5 ions in the case 
of vessels of the size ordinarily used. If this value be subtracted from 
the 8.5 ions per c.c. per second found over land, there remains about 
6 ions per c.c. per second attributable to causes which are not directly 
obvious, and this corresponds roughly to the ionization (4 to 6 ions per 
c.c. per second) observed over the ocean. 

The results of several investigators seem to indicate that, in vessels sur- 
rounded by thicknesses of water sufficient to absorb practically all gamma- 
ray radiation of the ordinary type, the ionization does not become reduced 
greatly below that found over the great oceans, nor does it diminish appre- 
ciably with increasing thickness of water, so that, if this ionization is due 
to an external radiation, this radiation must be of an extremely penetrat- 
ing type as compared with ordinary gamma-radiation. By using a vessel 
of ice, in order to be as free as possible from radioactive contamination, 
McLennan obtained a value as low as 2.6 ions per c.c. per second over 
Lake Ontario, and inclines to the view that even this small residual is 
attributable to lack of complete purity of the ice. On the other hand, 
results obtained by Kolhorster in balloon ascents up to 9.5 kilometers show 
an increase to about 80 ions per c.c. per second at this altitude, in a her- 



* Abstract of the paper presented at the annual meeting of the American Geo- 
physical Union, Washington, D. C, April 18, 1921. 



66 TERRESTRIAL MAGNETISM AND ELECTRICITY 

metically sealed, light, tight vessel ; moreover, the rate at which the appar- 
ent ionization increases with altitude in the neighborhood of 9 kilometers 
is such as to suggest that at altitudes but slightly greater, the ionization 
might attain enormous values. The validity of Kolhorster's results has 
been questioned by C. H. Kunsman in view of possible complications 
resulting from the effect of the low temperature on the insulating material 
used; if, however, they should be substantiated, they afford one of the 
most convincing evidences that one could wish as to the true cosmic nature 
of part at least of the so-called penetrating radiation. By the employment 
of precautions such as to prevent all uncertainty as regards leakage, and 
by the use of small pilot balloons, the writer is at present endeavoring to 
extend the observations of Kolhorster to greater altitudes. 

VARIATION OF RESIDUAL IONIZATION WITH PRESSURE 

The study of the variation of the residual ionization with pressure has 
a very important bearing upon the origin of that ionization. If the resid- 
ual ionization were due to alpha-rays emitted from the walls of the vessel, 
it would show practically no increase with pressure in the case of a vessel 
whose linear dimensions were of an order of magnitude greater than the 
range of the alpha-particles. Analagous remarks hold for the case of 
soft beta-rays emitted from the walls. In the case of a radiation of cos- 
mical origin there are three possibilities, viz, (1) a direct ionization by 
the primary radiation, (2) ionization by slowly moving electrons emitted 
from the gas by the primary radiation, (3) ionization by rapidly moving 
electrons emitted from the gas by the primary radiation, the penetrating 
power of the electrons being such as to enable them to go right across the 
vessel at atmospheric pressure. A fourth possibility resulting from emis- 
sion of electrons from the walls of the vessel by the primary rays, is indis- 
tinguishable from a corresponding emission resulting from radioactive 
contamination. Ionization of the first and second type would increase pro- 
portionally with the pressure until the pressure attained was so high that 
the primary radiation itself became appreciably absorbed in passing 
through the vessel. Effects resulting from the third t)rpe of ionization 
require more detailed consideration. 

At each point in the gas there will be a definite value of what we shall 
call the ionizing intensity /, i.e., the number of ions which would be pro- 
duced per c.c. per second in an element of gas at atmospheric pressure 
placed at the point in question. For the purpose of this definition, we 
may suppose the element of gas to be contained in a non-absorbing cap- 
sule, since it is of course not implied that the whole of the gas is at atmos- 
pheric pressure. The number of ions produced per c.c. per second in the 
gas at some point O where the pressure is p will be Ip, 

Let us consider an element of volume As 6r, situated at a point P at a 
distance r from O in some definite direction, dr being element of radius 
vector, and As being element of cross section of an elementary cone of 



TERRESTRIAL MAGNETISM AND ELECTRICITY 67 

solid angle d» drawn from O to P. The contribution of the element of 
volume to the value of / at O is 

^I = ^f(pr)dsdr 

where, assuming the secondary radiation originating within an element of 
volume to be proportional to the pressure therein, ^A^ dr dr is the second- 
ary ionization intensity at unit distance from P in the direction PO, on the 
basis of no absorption, and / (pr) is a factor inserted to take account of 
the absorption in passing from P to O, and also of the variation of the 
ionizing efficiency along the path of the ionizing agent. By writing / (pr) 
instead of / (r), we imply that the diminution of the ionizing intensity per 
unit distance (apart from spreading) is proportional to the number of 
molecules per c.c. In terms of the solid angle dw above referred to we 
have: 

A/ = iV/(/^r)pdrd» 

If we should now increase the pressure from p to p^, and diminish r 
to r, so that pr =■ p^r^^ and dr to dr^ so that pAr = /^idr^, the new element 
of volume contained between the radii r^ and (r^ + dr^) in the cone d«> 
will make the same contribution to the ionizing intensity at O as did the 
old element of volume comprised between r and (r + dr). The sum 
total of all the elements of volume in the vessel, corresponding to the 
lower pressure will, however, correspond to a sum total of elements of 
volume which, at the higher pressure, do not fill the vessel. Hence, the 
actual ionizing intensity at O will be greater at the higher pressure than 
at the lower pressure. Since q, the number of ions produced per c.c. per 
second at O, is obtained by multiplying / by the pressure p in atmos- 
pheres, we see that the increase in q, per atmosphere increase, should 
itself increase with the pressure. We may extend this statement so as to 
include in q the ionization due to the direct action of the external radia- 
tion, since this increases proportionally with the pressure. Thus, the 
actual ionization in the vessel, due to primary and secondary emission 
from the gas, will be less at one atmosphere than at any higher pressure. 
If then, the ionization-pressure curve should show a very small increase 
of ionization per atmosphere increase at high pressures, we know from the 
above that such increase per atmosphere is nevertheless greater ^ than the 
portion of the ionization due to primary and secondary action in the gas 
within the vessel at one atmosphere. We may infer that any greater ioni- 
zation found at atmospheric pressure is to be attributed to radiation from 
the walls of the vessel ; this radiation, owing to its absorption at the higher 
pressures, results in a diminishing rate of increase of ionization with pres- 



^ It would not be quite safe to extend this argument to imply that the ionization 
here referred to was necessarily greater than the true natural ionization in the open 
air, since a portion of the ionization in a volume of the external air occupying the 
space of the vessel would result from secondary radiations originating outside of 
that volume. 



68 TERRESTRIAL MAGNETISM AND ELECTRICITY 

sure. The foregoing discussion has been made for the case where the 
primary radiation is so penetrating as to be but little absorbed in passing 
through the gas in the vessel, even at the higher pressures, this being the 
case which is of interest in discussing the action of a radiation whose 
degree of penetration is comparable with that attributed to the cosmical 
penetrating-radiation. 

Experiments on the variation of the residual ionization with pressure 
have been made by several investigators, the most recent being those made 
under the writer's direction, by Dr. K. M. Downey and by Mr. H. Fruth. 
The main feature of the experiments of the latter investigators lay in the 
use of a comparatively large vessel (a sphere one foot in diameter), and 
the employment of certain special devices to insure freedom from errors 
due to leakage and lack of constancy of the batteries. Dr. Downey's obser- 
vations extended in the first instance up to 20 atmospheres, giving over 
this range a practically perfect linear variation with the pressure and an 
increase of ionization of about 1.2 ions per c.c. per atmosphere increase. 
On extending the observations to higher pressures, it was found that the 
linear relation ceased to hold in the neighborhood of about 27 atmos- 
pheres, and the curves finally became parallel to the pressure axis at pres- 
sures above 46 atmospheres. If one were to accept this parallelism with- 
out reservatiofi, he would be forced to conclude that the portion of the 
ionization within the vessel which was attributable to the direct or indirect 
action of the radiation on the gas was immeasurably small. 

Mr. Fruth's observations have been made for air, oxygen, and nitrogen 
up to pressures of 75 atmospheres, and for carbon-dioxide up to its lique- 
fying pressure, with sensibly the same results for all the gases used. 
While his curves do not attain as complete a parallelism with the pressure 
axis as do those of Dr. Downey, they correspond to an increase per atmos- 
phere of less than 0.75 ion per c.c. per second at the higher pressures.* It 
is worthy of note that the presence of radium-emanation in the gas would 
tend to increase the slope of the ionization-pressure curves. The normal 
emanation-content of the atmosphere is such as to produce about 2.3 ions 
per c.c. per second. Each additional atmosphere of air would, of course, 
carry with it its emanation-content, so that the increase per atmosphere 
for normal air resulting from the emanation-content alone would amount 
to 2.3 ions per c.c. per second per atmosphere increase. It is therefore 
necessary to carefully age the air before use. Recalling that the emanation 
activity dies to half value in 3.85 days, it will be readily seen that in the 
case of air 3 weeks old the effect of the emanation would become reduced 
to a negligible amount. In some of Dr. Downey's observations the air 
was aged for a month before use. 

In experiments of this kind it is of the utmost importance to insure 
complete saturation, and this matter was consequently tested very care- 



* Since this was written Mr. Fruth has found complete parallelism for air, oxygen, 
and carbon dioxide for pressures above 52 atmospheres, when the gases are per- 
fectly dry and dust-free. 



TERRESTRIAL MAGNETISM AND ELECTRICITY 69 

fully, the voltages used being considerably higher than those at which 
experiment showed saturation to have been attained at the higher pres- 
sures. One dement of uncertainty not usually considered in relation to 
the attainment of saturation must be here referred to. It pertains to the 
effect of dust nuclei. Such nuclei could theoretically cause a departure 
from a saturation which could not be reduced beyond a certain minimum 
however great the field might be, since increase of the field intensity could 
not reduce beyond a certain limit the probability of an ion's encounter 
with a dust nucleus during its passage across the vessel. Departure from 
saturation due to such a cause would not show up by the failure to attain 
apparent saturation with increasing field, and it would increase, moreover, 
with increase of the amount of gas (and consequently of dust nuclei) in 
the vessel. The comparatively good agreement between the results of Dr. 
Downey and those of Mr. Fruth, and the agreement of the various results 
of the latter investigator among themselves, suggest, however, that dust 
did not play an important role in the experiments, particularly when one 
remembers that the various experiments corresponded to different samples 
of gas, samples which had undergone, moreover, entirely different treat- 
ments. However, it is planned to make a very careful investigation of the 
effect of dust in this connection ; for, if the experiments of Dr. Downey 
and of Mr. Fruth represent a primary phenomenon, not explicable by sub- 
sidiary considerations of this kind, they carry with them the very remark- 
able conclusion that, of the ionization observed in a vessel at atmospheric 
pressure and ordinarily attributed to a penetrating radiation, less (and 
probably considerably less) than one ion per c.c. per second is to be ac- 
counted for as having its origin in a direct action of the primary radiation 
on the gas or in the action of a secondary radiation emitted from the gas 
by the primary radiation. 

EXPERIMENTS ON THE DIRECTION OF THE PENETRATING 

RADIATION 

An important light would be thrown upon the origin of the penetrating 
radiation if it could be shown to partake of a directive character. Experi- 
ments on this matter were originally made by Cook and by Wood, who 
interposed screens between the apparatus and its surroundings at various 
orientations. The experiments were inconclusive, but, as far as they went, 
seemed to indicate that the radiation came equally from all directions. 
A method of this kind is very seriously affected by lack of constancy of 
the residual ionization itself during the various experiments between which 
comparisons are subsequently made, and, for this reason, some experi- 
ments were undertaken by Miss J. Herrick under the writer's direction 
with the object of eliminating the main causes of uncertainty in the earlier 
experiments of Cook and Wood. The method used by Miss Herrick de- 
pends upon the fact that if gamma-rays pass through a thin sheet of metal, 
the ionizing electrons emitted from the side at which the rays enter differ 
as regards their number and speed from those which are ejected from the 



70 TERRESTRIAL MAGNETISM AND ELECTRICITY 

side at which the gamma-radiation leaves. If the penetrating radiation is 
of a gamma-ray type, it should show similar characteristics. The ratio of 
the subsequent ionization resulting from the incidence of gamma-rays on 
a surface to that resulting from the emergence of gamma-rays from the 
surface depends upon the material of the surface. The apparatus used 
consisted of two similar cylinders mounted with their axes in the same 
horizontal line. One semi-circular half of each cylinder was made of lead, 
and the other half was made of aluminum. The cylinders were provided 
with central rods which were connected to each other and to the insulated 
quadrant of an electrometer. By placing potentials of plus fifty and minus 
fifty volts respectively on the cylinders, the ionization currents in the gas 
could be caused to feed into the electrometer in such a way as to almost 
completely compensate. Several precautions to avoid leakage, and errors 
due to fluctuation in the potentials of the batteries were taken, the details 
of which it will be unnecessary to describe. 

To fix our ideas, suppose that an excess of gamma-radiation comes 
from above, and that in the case of one of the cylinders the lead half i^ 
uppermost. Then, as far as ionization due to the emission of electrons 
from the wall of the vessel is concerned, the ionization in the vessel in 
question (or rather the portion of it due to the excess of radiation com- 
ing from above) will be due to the emergence radiation from the lead, and 
the incidence radiation from the aluminum. An alteration of the effect 
should consequently be produced by rotating the cylinder through 180 
degrees, while the other cylinder is left untouched, its function being 
simply to act as a compensator for the purpose of minimizing effects re- 
sulting from an actual variation in the conditions during the experiment. 
Without here entering into details, it will be seen that it would be possible 
to obtain a comparison between the radiation coming in different direc- 
tions and the total radiation entering the vessel in so far as the ionization 
was due to the electrons emitted from the walls of the vessel and in so 
far as one assumed the penetrating radiation to partake of the nature of a 
hard gamma-radiation as regards the difference between the incidence and 
emergence effects in the case of the metals used. 

The first experiments performed by Miss Herrick in the laboratory of 
the physics building showed marked changes on rotating one of the cylin- 
ders, and by plotting a polar diagram representing the ionization due to 
radiation coming from the various directions it became possible to locate 
small quantities of radium in different parts of the building. The polar 
diagram, moreover, showed a hump indicating an excess of radiation com- 
ing from above. The apparatus was next moved to the astronomical 
observatory, where there was no radioactive material, and experiments 
again gave an indication of an excess radiation from above. In order to 
be free from all possibility of radioactive contamination, the writer next 
set the apparatus up in the attic of his house, and carried on observations 
over a period of 6 weeks, the observations being taken between the same 
hours each day. The attic of a dwelling house is not the most ideal situa- 






TERRESTRIAL MAGNETISM AND ELECTRICITY 71 

don for a quadrant electrometer, but on plotting the results for the various 
experiments there was again decided evidence of an excess radiation in 
the downward direction. The magnitude of the excess was such that, 
when the vessel was turned in the most favorable direction, the ionization 
was about 9 percent greater than the average, a result in comparatively 
good agreement with the observations of Miss Herrick made on the uni- 
versity campus. 

These experiments are only cited as of a preliminary nature, for there 
are certain sources of complication which must be removed before a cos- 
mical interpretation may be made of the results. Thus, the potential- 
gradient in the atmosphere will deposit active material from the atmos- 
phere on the roof of the building in which experiments are made. A 
simple calculation will show that the amount of such deposition may well 
be enough to seriously affect experiments of the kind described above. 
Similar remarks apply to the effect of radioactive material in the soil itself, 
and that deposited on the surface of the soil by the atmospheric potential- 
gradient. It is planned to continue the observations under conditions 
which, it is hoped, will eliminate these causes of uncertainty. 

THE EARTH'S PENETRATING RADIATION AND THE ORIGIN OF THE 

EARTH'S CHARGE 

In 1915, the writer proposed a theory of the origin of the earth's charge 
based on the assumption that high speed electrons were shot into the earth 
from the atmosphere as a result of a very slight radioactivity of the 
atmosphere itself, or as a result of the breaking up of the emanation nor- 
mally in the atmosphere. If one assumes that an electron of sufficiently 
high speed can have a range as great as 5 kilometers in the atmosphere, 
it is only necessary to postulate the emission of one such high speed cor- 
puscle per c.c. in the downward direction, each 100 seconds in order to 
account for the maintenance of the earth's charge. Or, viewed from 
another standpoint, since we know that about 5 pairs of ions are formed 
per C.C. per second in the atmosphere, it is only necessary to suppose that 
in the case of one out of every 500 pairs of ions formed a high speed cor- 
puscle of the above kind is emitted. The theory of passage of electrons 
through matter is not at all inconsistent with the postulation of g^eat 
ranges such as those required by the theory ; however, in 1917 Swann ^ 
put forward another theory in which the expulsion of the electrons from 
the atoms of air is brought about by the penetrating radiation from above, 
the hard nature of this radiation resulting in its emitting electrons from 
the air molecules almost exclusively in the downward direction. Under 
the influence of the electronic bombardment, the earth would charge up 
imtil the conduction current back to the atmosphere just sufficed to balance 
the effect. It appeared that if one assumed as many as 3 corpuscles to be 
emitted per c.c. per second from the atmosphere, it would only be neces- 
sary to postulate a range of penetration of about 9 meters in order to 

' Phys. Rev., 9, 555-557, 1917. 



n TERRESTRIAL MAGNETISM AND ELECTRICITY 

account for the maintenance of the earth's charge. As pointed out by 
the writer at the time, the chief difficulty facing a theory of this kind is the 
explanation of why the swiftly moving corpuscles do not produce, in the 
atmosphere, a much greater ionization than is observed. Difficulties of 
this kind assume a much less formidable aspect, however, when viewed in 
the light of modem views as to the properties of swiftly moving electrons. 
In 1918, V. Schweidler independently put forward the second of the above 
theories, and described an experiment carried out with the object of test- 
ing it. The aim of this experiment was the endeavor to observe a charging 
effect in a thick piece of metal as a result of corpuscles entering it, the 
piece of metal being surrounded by a shield from which it was insulated. 
Failure to observe any charging effect caused v. Schweidler to conclude 
that the replenishment of the earth's charge could not be brought about 
by a corpuscular radiation of the type discussed. As a matter of fact, the 
writer had performed an experiment somewhat similar to v. Schweidler's 
experiment in 1915, in connection with his earlier theory of corpuscular 
chai^ng. In this experiment an earthed vessel surrounded an insulated 
hollow cylinder connected to an electrometer. The rate of rise of poten- 
tial was noted, and a solid copper bar was then inserted in the hollow 
cylinder, the rate of rise being then again noted. By this device of per- 
forming two experiments in which the surfaces exposed were the same, 
surface effects were eliminated. As in v. Schweidler's experiment, no 
certain charging effect was observed ; and, while this weighed against the 
former of the theories above referred to, it was not felt that it formed so 
weighty an argument against the latter, for on that theory it might result 
that the penetrating radiation would shoot as many electrons out of the 
bottom of the cylinder as it shot in at the top, except for the absorption of 
the penetrating radiation itself within the cylinder. In other words, it is 
the coefficient of absorption of the penetrating radiation in the cylinder 
rather than the coefficient of absorption of the corpuscles which is of 
in:q)ortance. In a recent paper,^ R. Seeliger discusses the origin of the 
earth's charge. He considers v. Schweidler's experiment as conclusive 
evidence against any theory which postulates a corpuscular replenishment 
at all parts of the earth, but raises the question as to whether a corpus- 
cular replenishment may not take place in certain limited areas, in polar 
regions for example. It is to be observed that any asstunption of this 
kind invites, in their most serious form, difficulties associated with the 
ionization which might be expected to result from a passage of the cor- 
puscles through the atmosphere. For a concentration of the corpuscular 
current in a limited r^on would result in greatly increased ionization in 
that region, and on the assumption that a corpuscle produces 50 ions per 
centimeter of its path and that the coefficient of recombination of ions is 
1.6X10^, it can readily be shown that, unless the area of precipitation 
were more than one thousandth of the area of the earth, the conduc- 
tivity produced in the air in the region of precipitation would be so great 
that, for a potential gradient of 150 volts per meter, one would calculate 



^AnnaUn drr Physik, 63, 464-481. 



TERRESTRIAL MAGNETISM AND ELECTRICITY 73 

for this region alone a total conduction current greater than the corpuscu- 
lar current. In other words, there is a lower limit to the value which one 
may assume for the region'of precipitation. Thus the avoidance of diffi- 
culties concerned with the failure to directly measure a corpuscular cur- 
rent, by relegating that current to regions where experiments have not 
been made, does not avoid what is perhaps one of the most serious diffi- 
culties confronting any corpuscular theory, that of reconciling the com- 
paratively small ionization of the atmosphere with the passage through 
it of about 1500 high speed corpuscles per square centimeter per second. 

THE CONDUCTIVITY OF THE UPPER ATMOSPHERE 

The paper concluded with a reference to the importance of a knowledge 
of the conductivity of the upper atmosphere in relation to the origin of 
the earth's charge and allied phenomena, and the author described an ex- 
periment in progress at the University of Minnesota designed with the 
object of measuring the distance of the supposed conducting layer by 
measuring the time taken by wireless waves to reach that layer and return. 



RECENT RESULTS DERIVED FROM THE DIURNAL-VARIA- 
TION OBSERVATIONS OF THE ATMOSPHERIC- 
ELECTRIC POTENTIAL-GRADIENT ON 
BOARD THE CARNEGIE "^ 

By S. J. Mauchly 

The Department of Terrestrial Magnetism, in accordance with its direc- 
tor's plans, has for many years been making not only magnetic but also 
atmospheric-electric observations aboard its survey vessel, the Carnegie, 
It is thus contributing the chief data for mapping both the earth's mag- 
netic field and its electric field. Furthermore, since 1915 numerous obser- 
vations have been made aboard the Carnegie to determine the nature and 
magnitude of the changes in the electric condition of the atmosphere which 
take place during a 24-hour cycle. 

For the potential^gradient the general procedure in the diurnal-variation 
observations is to make a set of 20 observations during each of 24 consecu- 
tive hours. The observations for such a set require about 20 minutes 
and their mean value is referred to the mean time for the set. From 
deductions .based on the observations made prior to April, 1916, it ap- 
peared that the diurnal variation of the potential-gradient over the oceans 
probably did not differ much from that which has been found at many 
land stations ; that is, they indicated two rather pronounced maxima and 
two minima during a 24-hour period.' However, very few data were 



* Preliminary report presented before the American Geophysical Union, with 
amplifications. 

""Researches of the Department of Terrestrial Magnetism," Vol. Ill, pp. 416-420^ 
Washington (1917). 



74 



TERRESTRIAL MAGKETISM AND ELECTRICITY 



available from oceans other than the Pacific, and as pointed out in the 
report just cited, a large percentage was derived from series of observa- 
tions which were terminated by the advent of unfavorable weather. It 
should also be noted in passing that Swann ^ a year later in discussing 




Fig. 3. Diurnal variation of electric potential-gradient on the oceans, 

plotted according to Local Mean Time. 

the results of the observations for the year ending February 20, 1917, 
states that **the effect of the 12-hour Fourier wave is less important in 
the present curves than in those already published." 

The largely increased amount of material which has accumulated since 
1915 makes it now possible to reject nearly all data corresponding to less 
than a 24-hour series and still have 45 practically complete 24-hour series 
available. The data for each series, therefore, correspond to an actually 
occurring sequence of phenomena, and the mean results are free from the 
errors which would result from combining the results of partial series of 
observations. 

Of the 45 diurnal-variation series referred to, 30 were made in the 
Pacific, 5 in the Atlantic, and 10 in the Indian Ocean ; the combined data 
represent about half the earth's surface. The means corresponding to 

*W. F. G. Swann. "Supplementary report on atmospheric-electric observations 
made aboard the Carnegie from May 17, 1916, to March 2, 1917," in "Annual Report 
of the Director of the Department of Terrestrial Magnetism" for the year 1917. 
Year Book of the Carnegie Institution of Washington, 1917, p. 282. 



TERRESTRIAL MAGNETISM AND ELECTRICITY 



75 



the separate oceans, as derived from 39 series, are represented in figure 3. 
They show : ( 1 ) That the mean diurnal-variation curves for the Pacific, 
Atlantic, and Indian oceans are similar in form; (2) that the principal 
component of the variation consists of a 24-hour wave, and (3) that the 
times of occurrence of the chief phases of this wave, when referred to 




CQivii) 

Pig. 4. Diurnal variation of electric potential-gradient on the oceans, 
plotted according to Greenwich Mean Time. 



local time, diflfer for the several oceans by amounts which correspond 
approximately to the differences between the respective mean longitudes, 
for the several oceans, of all the points at which observations were made. 
Since the curves of figure 3 suggest the simultaneous occurrence of 
maximum (or of minimum) phase over all three oceans, it was decided 



76 TERRESTRIAL MAGNETISM AND ELECTRICITY 

to refer the results of each series of observations to Greenwich Mean 
Time (civil), and recompute the means for the separate oceans on this 
basis. The results are shown in figure 4, together with a curve which 
includes the data from 6 recent series received from the vessel after the 
curves in figure 3 had been prepared. The differences between the several 
curves of figure 4 are of course not to be thought of as representative of 
separate characteristics, since the smoothness of the respective curves is 
seen to be closely related to the number of component series. 

The curves of figure 4 show a decided similarity to land results for 
high latitudes and also to many of the winter curves obtained in ordinary 
latitudes. Indeed, if differences in local mean time are taken into account, 
it appears that for many land stations at which the single diurnal wave 
predominates, there is approximate simultaneity as to the time of occur- 
rence of maximum (likewise, of minimum), and this at a time which is 
in general agreement with what is indicated by the curves of figure 4. 
For the summer, however, as is well known, most land stations show, in 
addition to the 24-hour wave, a decided secondary wave which seems to 
occur in general at about the same local mean time at different stations. 

The minimum value of the potential-gradient, according to figure 4, 
occurs at about 4^ A.M., G.M.T.,.and in view of the fact that for observa- 
tories in western and central Europe the difference between local and 
Greenwich time is not great, this may account for the fact that various 
authorities have assumed the occurrence of the principal minimum at 
about 4^ A.M., local time, to be a rather general characteristic for most 
stations. It is also significant to note that Mache and v. Schweidler ^ long 
ago p<Mnted out that the phase angle of the 24-hour wave varied greatly 
from station to station while the phase angle of the 12-hour wave was 
approximately the same for nearly all stations. Although the phase angles 
of the 24-hour Fourier waves for the European stations show among 
themselves very much greater differences than can be accounted for by 
the rather small differences in longitude, it must be borne in mind that 
the results of harmonic analyses are dependent upon local meteorolc^cal 
and cultural, and sometimes topographical and instrumental, factors as 
well as upon any general characteristics which the potential-gradient may 
possess. 

In the present investigation no account has been taken of possible 
changes in the characteristics of the diurnal variation with latitude and 
with time of year, except to ascertain that the preponderance of the 
24-hour wave and the approximate progress on a universal-time basis 
seem to hold throughout the year and for wide ranges of latitude. The 
present results are, therefore, to be considered as provisional and repre- 
senting only a general yearly average. In fact, investigations under way 
show that considerable modification in detail is to be expected as more 
observational material becomes available. The data from 45 practically 

^ H. Mache tind E. v. Schweidler, "Die Atmosphirische Elektrizitat," p. 27. Braun- 
schweig, 1909. 



TERRESTRIAL MAGNETISM AND ELECTRICITY 77 

complete series of diurnal-variation observations aboard the Carnegie, 
representing a general distribution over most of the accessible ocean-areas 
indicate* therefore, as a preliminary result, that the chief component of 
the diurnal variation of the potential-gradient over the major portion of 
the earth {especially the oceans) is a wave of 24-hour period which occurs 
approximately simultaneously in all localities. 

A fact of considerable interest is that the diurnal- variation curves for the 
potential^adient derived from the Carnegie observations are very similar 
to curves which represent the relative frequencies of the Aurora Borealis, 
as observed at several European stations, and also to curves representing 
the diurnal distribution of certain classes of magnetic disturbances, when 
all are referred to the same time-basis. It may also be pointed out that 
owing to the non-coincidence of the earth's magnetic axis with its axis of 
rotation, the time of daily potential-gradient maximum, as indicated by 
the ocean curves, corresponds approximately to the time when the earth's 
north magnetic pole, for example, is nearest to the sun, while the daily 
minimum occurs, in a general way, when this pole is farthest from the 
sun. The actual times of maximum and minimum, however, appear to 
depend upon the positions of both magnetic poles and the fact that their 
longitude difference is not 180°. These correlations appear to support the 
assumptions of various investigators that the earth's electric charge and 
resultant field may be very intimately related to an electric radiation from 
the sun. The best evidence as to the extent of this support will probably 
result from a study of the details of the diurnal-variation curves' corre- 
sponding to various positions of the earth in its orbit. Reductions with 
this end in view are under way and it is hoped that sufficient data will 
soon be available to yield some information on this point. 

The making of diurnal-variation observations in atmospheric electricity 
by eye readings is always a burdensome procedure; the carr3dng on of 
such work aboard a vessel is not only arduous but also difficult. In this 
connection the utmost credit is due the several commanders of the Car- 
negie, during her various cruises, and to all the observers who participated 
in the observational work. 

I am indebted to the director, Dr. L. A. Bauer, for his constant interest 
in and encouragement of the work in hand, and for a suggestion of the 
possibility of finding in the asymmetry of the earth's magnetic field an 
explanation of the observed diurnal variation on a universal-time basis. 
I am also greatly under obligations to the members of the Department of 
Terrestrial Magnetism who assisted in the reduction of the observational 
data, especially to Dr. G. R. Wait, both for valuable assistance and helpful 
suggestions. 

The full publication of the observational data and discussion of results 
will be deferred until after the completion of the present cruise of the 
Carnegie. Department of Terrestrial Magnetism, 

Carnegie Institution of Washington. 



SUGGESTIONS RELATIVE TO THE APPLICATION OF MATH- 
EMATICAL METHODS TO CERTAIN BASIC PROB- 

LEMS OF DYNAMIC OCEANOGRAPHY 

By G. F. McEwbn 

Investigations of the ocean have generally been carried on by geogra- 
phers and geologists, oftentimes incidentally to those of other divisions 
of these extensive fields of science. Accordingly, qualitative methods so 
characteristic of geography and geology have been widely used in oceano- 
graphic investigations. Such qualitative methods and the empirical treat- 
ment of quantitative field observations have been very suggestive, have 
stimulated interest, and led to certain broad generadizations that are 
essentially correct. However, there has been a tendency toward rather 
loose reasoning and lack of consideration of established quantitative prin- 
ciples of physics, which has resulted in certain erroneous conclusions. 

Must we admit that the complexity of such geophysical phenomena 
renders careful reasoning and quantitative treatment impossible of attain- 
ment ? Probably many would at first answer yes, but let us consider the 
matter further before expressing an opinion. Within the past fifty years 
a few scientists have undertaken, by means of a definite formulation of 
specific problems, to apply mathematics to ocean data, and thus to con- 
tribute to a system of demonstrable principles applicable, in general, to 
all similar cases ; and attention has been increasingly directed to this type 
of research. Important advances have thus been made, and serious errors 
in certain former conclusions have been discovered, although, especially 
in some of the earlier attempts at mathematical applications, significant 
errors arose from incorrect assumptions and failure to appreciate impor- 
tant attributes of such "field," or natural problems. At first, men accus- 
tomed to the problems of laboratory physics attempted to deduce physical 
laws of the sea from results of laboratory studies, and certain precon- 
ceived assumptions regarding oceanic conditions. They also worked 
under the disadvantage of having very inadequate data. As more accu- 
rate and exhaustive field data accumulated, attention was directed more 
to interpreting and coordinating field observations rather than to depend- 
ing on the speculative and unsound method of imposing on the sea purely 
theoretical laws deduced from laboratory researches. 

Mohn's pioneer investigation of 1887,^ based on the deduction of the 
changes in form of the surface that would give rise to currents actually 
produced by winds, variation in barometric pressure, and specific gravity, 
was a great advance beyond earlier attempts at a precise treatment of 
ocean data, and doubtless contributed greatly to the development of the 
more satisfactory methods of today. Among the later results thus worked 

*Mohn, H. 1887. The Norwegian North Atlantic expedition, 1876-1878: The 
North Sea, its depths, temperature and circulation. (Christiania, Grondahl), 212 
pp., 48 pis. 

78 



PHYSICAL OCEANOGRAPHY 79 

out are Ekman's * hydrodynamical theory of oceanic circulation, which 
pertains especially to wind-driven currents, and was undertaken at Nan- 
sen's ^ suggestion ; and B jerknes's * convection theory which pertains 
especially to the determination of ocean currents due to differences in 
specify gravity. Later his pupil, Sandstrom,* devised a much more rapid 
and accurate method of computing such currents. 

The Norwegian investigator, Jacobsen,** in certain more recent quanti- 
tative investigations pertaining to the Atlantic near Denmark, obtained 
encouraging results by giving special attention to the alternating con- 
vective motion of small masses of the water, or to the "mixing phenom- 
ena," as he called it. His researches afford strong evidence in support of 
the idea suggested by earlier qualitative studies, that in lakes and oceans, 
very small or elementary masses of the water are moving at random in a 
manner somewhat analogous to the motion of molecules in a gas, except 
that the direction of motion in large bodies of water is mainly vertical, 
although the resultant vertical flow may ze zero. This phenomenon of the 
interchange of small masses of water has been variously referred to as an 
alternating convective circulation, mixing phenomenon, eddy or vortex 
motion, and turbulence. Jacobsen's and other recent investigations in this 
field indicate that this phenomenon is the cause of the processes of diffu- 
sion, heat conductivity, and f rictional resistance peculiar to oceanic condi- 
tions. Comparable values of the **Mischungsintensitat," a coefficient indi- 
cating the intensity of the rate of interchange of small water masses, have 
been deduced independently from the distribution of temperature and 
salinity, and also from the dynamical treatment of current observations. 
Thus studies of temperature and salinity distributions may yield appro- 
priate values of the f rictional resistance, an essential factor in the dynami- 
cal solution of ocean-current problems as well as certain tidal problems. 
This f rictional resistance about which there is so little definite information 
appears to vary widely with the locality, wind velocity and other factors. 
It is not a "physical constant" of the substance, water. 

The precise nature of this mixing motion can not be directly determined, 
but various reasonable assumptions regarding it can be made, and com- 
bined with known fundamental facts into a quantitative theory or general- 
ization, from which deductions can be made, and tested by comparison 
with observations. Encouraging results already reached appear to justify 



'Ekman, V. W. 1905-06. On the influence of the earth's rotation on ocean cur- 
rents. Arkiv for Matematik, Astronomi och Fysik, 2, 1-53, 1 pi. and 10 figs. 

'Nansen, Fridtjof. 1902. The Norwegian North Polar Expedition, 1893-1896. 

Scientific Results, Vol. Ill, Longmans Green & Co. London, part IX, pages 1-427. 

33 pis. 
' Bjerknes, V. F. K. 1901. Circulation relative zu der Erde. Ofversikt af Kongl. 

Vet.-Akad. ForhandL. 58, 739-757. 
*Krumniel, O. 1911. Handbuch der Ozcanogriphic (Stuttgart, Engelhorn), 2, 

xvi, 766 pp., 182 figs, in text. . 

■Jacobsen, J. r. 1913. Beitrag zur Hydrographie der Damschen Gewasser. 
Medd. Komm. Havandersogelser (Hydrografi), 1, no. 94, pp., 14 pis., 17 figs, 
in text. 



80 PHYSICAL OCEAMOGRAPHY 

further efforts in this direction and point to the possibility of a satisfac- 
tory coordination of the various phenomena of conduction, diffusion, and 
fluid friction by means of a single mathematical theory of the mixing 
motion. Such an investigation, if successful, would enable one to deduce 
the temperature distribution in a body of water gaining heat from solar 
radiation of given intensity, and losing heat by evaporation. Investiga- 
tions of this simplest case would thus correlate under definite physical 
principles all of these various thermal phenomena. Again, by so amend- 
ing such results as to include the effect of a given flow or current on the 
distribution of temperature determined for the above simplest case, esti- 
mates of a current could be made from the difference between the undis- 
turbed and the actual temperature distribution. This has been partly 
worked out and applied to the determination of the velocity of upwelling 
in the San Diego region. Thus the temperature disturbance can be 
quantitatively treated as an effect of a current, without regard to its 
dynamical causes. Qualitative ccmclusions relative to ocean currents have 
long ^o been reached from essentially the same general idea, and this 
fact points to the possibility of such a quantitative theory. Such general 
quantitative laws of the relation between currents and temperature de- 
partures from the undisturbed state might be combined with Bjerknes's 
dynamical theory, and thus afford a means of deducing answers to more 
involved questions, such as the following : Given the distribution of solar 
radiation over the surface of a body of water having given boundaries, 
and a known initial temperature distribution, to determine the resulting 
temperature distribution and circulation for any later time. The results 
of similar determining conditions have not infrequently been either 
assumed or surmised in order to form a basis for more far-reaching 
oceanographic conclusions. But it is by the precise formulation and suffi- 
ciently accurate solution of suitable specific problems sufficiently in accord 
with actual conditions that general laws of oceanic phenomena can be 
discovered and tested. And the greater the variety of such ideal problems 
that we are in position to attack, the greater will be our progress in the 
precise and detailed study of the physics of the ocean. Also, it is to be 
expected that a satisfactory physical theory, especially of the mixing 
phenomenon, would greatly aid in the solution of certain problems of 
sedimentation and ocean chemistry. 

One problem of ocean physics, whose simplest special case would be to 
deduce the vertical temperature distribution in a body of water exposed 
to solar radiation of approximately uniform intensity over the surface 
and losing heat by evaporation and conduction from its surface, has 
received very little attention except of a qualitative or speculative nature. 
Yet this problem appears to be fundamental in precise oceanographic 
investigations. Accordingly, the author has for some time attempted to 
work out a solution, and after trying and rejecting various assumptions, 
has reached encouraging preliminary results by using certain concepts 
from statistical mechanics, combined with elementary laws of heat and 
radiation. It is hoped that these studies will have progressed far enough 
for publication within a year or two. It is also the intention, after this 



PHYSICAL OCEANOGRAPHY 81 

work on temperatures is in a more finished state, to investigate the prob- 
lem of diffusion in the sea by similar methods applied first to certain of 
the numerous salinity determinations made by the Scripps Institution. 
Problems of the t3rpe mentioned in this paper form an extensive and 
promising field of fundamental importance in oceanography, and demand 
the attention of all investigators interested in promoting quantitative 
studies of the sea, but probably only a few will desire to engage actively 
in their solution. 

It has formerly been necessary to make a great deal of use of such 
scattered data as the investigator could find as a basis for theoretical 
work. Much has been, and doubtless will be, accomplished in that way. 
And all original detailed data, as well as summaries and deductions there- 
from, should be accessible in some way to investigators, even if publication 
is not always practicable. But such a procedure has obvious disadvan- 
tages, such as insufficient or unknown precision, incomplete data, or lack 
of significant factors that may impair or greatly restrict the conclusions. 
Therefore it is also necessary to conduct special programs of observations, 
designed with reference to particular problems, in order to improve and 
supplement the above more extensive and preliminary type of work. Thus 
selection of the locality, season, etc., and the observation of all relevant 
phenomena affords as nearly as possible a realization of the advantages 
of the physicist who controls the conditions affecting his laboratory ex- 
periments. For example, serial temperatures observed in the central part 
of a high-pressure area away from currents or land, and where prevailing 
great depths provide results corresponding to the simplest conditions, 
would be of great aid in the study of ''normal" temperature gradients. 
Such observations should also be accompanied by observations on the 
intensity of solar radiation, turbidity, salinity, and evaporation, and should 
be continued through different seasons and times of day in order to pro- 
vide the most important kinds of data. Very little of this intensive type 
of work, carried on with sufficient continuity and completeness, has been 
done, and it has been restricted to certain portions of small inland seas or 
inshore regions. Although results thus obtained are valuable in them- 
selves and as a means of interpreting such fragmentary and widespread 
data as may be available, they can not take the place of similar intensive 
work at selected stations throughout the ocean. Actual conditions in 
typical areas of the great ocean must be carefully observed and studied, 
if any reasonable approach to exhaustive oceanographic investigations is 
to be realized. 

In this paper I have dwelt especially on the deductive treatment of 
ocean problems, because of the great need of improvement in this aspect 
of the subject. Although admitting that purely empirical or statistical 
methods are indispensable in assembling and coordinating various kinds 
of field data, it seemed desirable to urge the need of progress from such 
empirical results toward the goal of a complete deductive treatment 
carried out in accordance with known generalizations of physics. 



82 PHYSICAL OCEANOGRAPHY 

STATE OF PROGRESS IN CONTINUOUS RECORDING 
OCEANOGRAPHICAL INSTRUMENTS 

By Albixt L. Thubas 

The modern tendency in physical research is to replace indicating instru- 
ments by recording instruments wherever possible. This has bmi espe- 
cially true in the science of meteorology where the recent advances have 
been brought about almost entirely by the remarkable improvements and 
developments in recording instruments. In the related science of physical 
oceanography there are practically no recording instruments now in gen- 
eral use, except possibly the tide-gage. If meteorology has been so greatly 
benefited by such instruments, surely in oceanography, where the changes 
in the physical properties are so much more regular and therefore more 
easily interpreted, great advances should be looked for through the addi- 
tion or substitution of recording instruments. 

Heretofore the methods of collecting physical data have been such that 
no complete knowledge of the physical characteristics of the particular 
body of water under investigation have been obtainable as the work is 
progressing. The procedure has been to lay out stations, as intelligently 
as possible along courses throughout the region of the ocean to be studied 
which will give the most important information. At these various sta- 
tions with the use of water bottles and reversing thermometers samples 
and temperatures of the ocean water are obtained at various depths down 
as far as the investigations are carried. The thermometers are read as 
soon as the water bottles are drawn up and samples of the water are 
stored in bottles which are later chemically measured for salt content in a 
laboratory on shore. The several disadvantages of this method are ap- 
parent: (1) No working knowledge of the ocean water is immediately 
obtainable and consequently no rearrangement or addition of stations can 
be made from an examination of the data taken. This is very important 
especially where our knowledge of the ocean is limited and one wishes to 
explore the magnitude and extent of the surface and submarine currents. 

(2) It is impossible to obtain a corroboration of any data where there 
may be doubt as to the accuracy or reliability of single observations. 

(3) The data taken are usually inadequate and especially so at those sta- 
tions where vertical lines of observations pass through various strata of 
water of different salinity, temperature and density. Curves and cross 
sections plotted from data taken in these regions are usually a matter of 
approximation and give very little information as to the mechanism of the 
mixing of waters of widely different properties. These observations are 
particularly inadequate in such regions as the southern end of the Grand 
Banks of Newfoundland where the cold waters of the Labrador Current 
merge into the warm saline waters of the Gulf Stream. 

With the object of improving the technique of the science of physical 
oceanography, an effort has been made in recent years to develop practical 



PHYSICAL OCEANOGRAPHY 83 

recording instruments which are sufficiently rugged and simple to be used 
on shipboard. The most important physical properties of the sea of 
which a continuous record should be made, are temperature, salinity, den- 
sity, velocity and direction. The first three properties are so related that 
any one can easily be deduced from a measurement of the other two. The 
properties most easily measured are temperature and salinity. Salinity 
is defined as the number of grams of salts in a liter of sea water. From 
a c(Hisideration of the properties of sea water that vary with the salinity, 
the electrical conductivity seems to be the most susceptible to continuous 
measurement if the difficulty due to the variation of conductivity with 
temperature can be overcome. Such a method consists in measuring the 
ratio of the resistance of sea water in two equal or nearly equal electro- 
lytic cells, one cell containing sea water of a known salinity and the other 
having the sea water to be measured flowing through it. The ratio is 
obtained by a Wheatstone bridge, using alternating current to eliminate 
polarization effects in the cells. A record of the resistance ratios of the 
two cells is made by an automatic electrical recorder. By immersing the 
two cells in the same temperature bath almost complete compensation of 
temperature changes is effected. 

A continuous record of the temperature of the ocean is most easily 
obtained with a platinum resistance thermometer and an automatic regu- 
lating Wheatstone bridge quite similar to the continuous salinity recorder. 
This instrument has been used successfully on shipboard for several years 
in the region of the Grand Banks of Newfoundland and some very inter- 
esting records have been obtained which show the distribution of tem- 
perature and thereby indicate the location j)f ocean currents and also give 
a knowledge of their boundary conditions which could hardly be obtained 
by repeated single measurements of temperature. 

The continuous recording instruments for temperature and salinity de- 
scribed above give only surface measurements but they could easily be 
constructed for making measurements below the surface. This would 
require the use of an insulated cable of 4 or 5 conductors which would 
be sufficiently strong and flexible. During 1918-19 in connection with 
submarine listening experiments there were constructed reinforced cables 
similar to these, which could be repeatedly wound on to and off of a drum 
and would withstand a weight of 400 to 500 pounds. Data from these 
instruments gave accurate curves of temperature, salinity and density 
from the surface down to a depth of probably 500 meters, which is the 
most interesting part of the ocean dynamically. 

R. A. Daly of Harvard University has developed and built a thermo- 
graph which can be anchored in very deep water and will give a record of 
temperature for a period of several days. The instrument has an inter- 
mittent mechanism which gives periodic photographs of a mercury col- 
umn. This instrument was specially designed to withstand very high pres- 
sures and it should be especially valuable in studying the small variations 
of temperature at great depths in the ocean. 



84 PHYSICAL OCEANOGRAPHY 

The measurement of the movement of waters in the ocean has been 
quite difficult to perform experimentally. This difficulty has been due 
chiefly to the non-continuity of measurements and the unknown move- 
ments of the vessel from which the measurements are made. Dr. Hans 
Pettersson of Goteborg, Sweden, has solved this problem by his photo- 
graphic current meter which will give a continuous record of both direc- 
tion and velocity for a period of two weeks. This instrument with the 
use of special anchors and buoys, can be firmly secured at any depth down 
to 300 meters. The difficult problem which had to be solved in this instru- 
ment was the transfer of the motions of a propeller through a water tight 
case containing the recording apparatus without the addition of friction. 
This was accomplished by a magnetic coupling. 

Dr. Pettersson has also developed densimeters to be used from shore 
stations which give a record of the movements of the waters of various 
salinities into and out of the Swedish Fjords. These instruments consist 
of vessels or cans whose density is equal to the average density of the 
Fjord waters. As the submarine waves of high salinity come in from 
the ocean these vessels will rise and a record of their height is automati- 
cally recorded. Some interesting theories of submarine waves have re- 
sulted from this work and the correlation between the variations of salinity 
and the abundance of fish in these Fjords is being studied. 

This briefly describes the recent developments in recording instruments 
and in conclusion I wish to suggest the possible application of these in- 
struments to future research in physical oceanography. 

A comparison of the yearly observations in the region of the Grand 
Banks of Newfoundland shows that the volume and strength of the 
Labrador Current have a decided influence on the course of the Gulf 
Stream in that vicinity. In some years the Gulf Stream was found almost 
up to the southern end of the Grand Banks and in other years as far 
south as the 40th degree of north latitude, a variation of over 100 miles. 
An accurate knowledge of the volume, velocity and location of these cur- 
rents from time to time and correlation with meteorological conditions 
might yield results of great interest. 

This information could be obtained by the use of recording instru- 
ments in the straits of Florida and across the Gulf Stream before it 
branches out east of the Grand Banks of Newfoundland. 

With continuous salinity and temperature recorders placed on trans- 
Atlantic vessels a complete record of the variation of temperature salinity 
and density could be secured across the Atlantic from month to month. 
These instruments would make measurements at a constant depth below 
the surface and might throw considerable light on the hydrodynamics of 
this part of the Atlantic. 

It seems to me that the science of physical oceanography has passed the 
period of exploration and has now reached that stage in its development 
which calls for a program of research on a large scale with most carefully 
thought out plans of systematic investigation extended over long periods 



PHYSICAL OCEANOGRAPHY 85 

of time. Results from such an undertaking I believe can be most suc- 
cessfully accomplished by the use of recording instruments. 

Western Electric Company, 

New York City. 



PRESENT STATUS OF RESEARCHES ON MARINE 

SEDIMENTS IN THE UNITED STATES f 

By Thomas Wayland Vaughan * "> 

INTRODUCTION 

The ocean of today stands at the end of a succession of oceans that 
* have existed since land and water were first divided from each other on 
the earth's surface. This fact, admitted by everyone, needs to be empha- 
sized in order to make clear the transcendent importance of the study of 
marine sediments. It is possible to measure the depth and the tempera- 
ture of the waters of the present ocean, to sample its waters from the sur- 
face to the bottom of its greatest abysses and examine them chemically, 
and to measure directly or to infer from measurable factors its currents. 
It is also possible to study the sediments deposited on the floor of the ocean 
and around its margins. These and other features of the present ocean 
can be known by direct processes but over a large part of the earth's sur- 
face where there was once sea there is now only land, and the depth, tem- 
perature, chemical composition, and currents of bodies of waters no longer 
existent cannot be measured. That seas once extended over regions now 
land is known through the record made by the sediments and these sedi- 
ments supply the fundamental data for recognizing the physical features 
of the vanished oceans. 

Considerable information has already been acquired on modern marine 
deposits and preliminary maps of parts of the ocean floor have been made. 
Among the sources of this information are the studies of Bailey and 
Pourtales, the classic work of Murray and Renard, Murray, and Murray 
and Lee, Murray and Philippi, and Philippi, the many papers by Thoulet, 
several papers by Boggild, including his recently published "Meeresgrund- 
proben dcr Siboga-Expedition," papery by Walther, and the studies of the 
shoal-water deposits of Florida and the Bahamas and Murray Island, 
Australia, with which I have been associated.' Of course there are many 
other authors but I have given the names of those who have done most in 
areally mapping deposits on the bottom of the sea. The great leaders are 
Murray and his associates, among whom Philippi is to be reckoned, and 
Thoulet. It is believed that the characteristics of some deposits and the 
relations of these deposits to the conditions under which they formed have 



^ Published by permission of the Director of the U. S. Geological Survey. 

*K. Andr^e is the author of a useful bibliography on literature on marine sedi- 
ments published between 1841 and 1911. See his article, Uber Sedimentbildung am 
MeeresDOden, Literaturzeichniss : Geolog. Rundschau, 3, 1912, 524-338. 



86 PHYSICAL OCEAXOGRAPHY 

been ascertained with enough accuracy to admit their use in interpreting 
geological history ; but how inadequately some relations are understood is 
exemplified by the presence of red clay at comparatively shallow depths, 
4000 meters, in the enclosed deep basins of the East Indian Archipelago. 
Boggild says it is necessary to conclude that the capacity of the water to 
dissolve calcium carbonate is greater in the enclosed basins of the East 
Indian Archipelago th^n in the open ocean.^ Although considerable is 
known about marine sediments, the information is far below what is 
needed to understand many important features of sediments in the modem 
oceans and to supply a basis for interpreting ancient sediments. 

RESEARCHES ON MARINE SEDIMENTS IN AMERICA 

There is under the Division of Geology and Geography of the National 
Research Council of the United States a Committee on Sedimentation 
composed of fourteen members, of which I have the honor to be chair- 
man. This committee is divided into seven subcommittees, as follows: 
universities and colleges east of the Allegheny Front; universities and 
colleges between the Allegheny Front and the Rocky Mountains ; univer- 
sities and colleges west of the Rocky Mountains ; state geological surveys ; 
chemical and physical researches on sediments ; field description of sedi- 
ments ; preparation of a treatise on sedimentation. The report of the com- 
mittee for the year ending on April 28 has been transmitted to the chair- 
man of the Division of Geology and Geography and is available in 
mimeographed form to interested persons. 

No attempt will be made to give an account of the work of the com- 
mittee, as that would consume too much time, but it will be said that its 
scope includes both modern and ancient sediments and both continental 
and marine deposits. One of the purposes of the committee is to ascer- 
tain and to follow all current investigations on sediments within the United 
States and the machinery for accomplishing this purpose is good. 

The U. S. Bureau of Fisheries is trying to arrange for a study of the 
sediments of the Bay of Maine but the plans have not yet been completed ; 
and an attempt is being made to have the sediments of Chesapeake Bay 
studied cooperatively by the Bureau of Fisheries, the U. S. Geological 
Survey, and Johns Hopkins University, but the actual work on the bot- 
tom samples has not begun. Prof. G. D. Louderback has been trying to 
study the bottom deposits collected principally by the Bureau of Fisheries 
in San Francisco Bay. Some preliminary information on the samples has 
been published but the investigation has progressed slowly. Two re- 
searches with which I have been concerned have had grave difficulties. 
One of them, the study of the sediments off the mouth of Mississippi 
River, as representing an area in which great quantities of terrigenous 
material are being deposited, has come to a standstill with the resignation 
of Mr. E. W. Shaw from the U. S. Geological Survey. The other study 



* Boggild, O. B., Mceresgrundproben der Siboga Expedition : Siboga Expcditic, 
Mon. 45, p. 11, 1916. 



PHYSICAL OCEANOGRAPHY 87 

is on the shoal-water deposits of southern Florida and the Bahamas, as 
representing areas in which very little or no terrigenous material is being 
deposited, except at the north end of the Florida reef. Fortunately several 
papers on the Floridian and Bahamian samples themselves and on cor- 
related phenomena, such as papers by Dole and Qiambers and Wells on 
the chemistry of the waters, bacteriological studies by Drew and Keller- 
man, and temperature records by me, have been published, but a large 
quantity of data remains unpublished. I am hopeful that within a rela- 
tively few months all data already acquired, which include Ekman current 
meter measurements at about 15 stations, may be prepared for printing. 

The researches of F. W. Clarke and W. C. Wheeler on the inorganic 
constituents of the skeletons ol marine organisms is of prime importance 
but such work needs to be correlated with studies on the bottom deposits 
themselves. The research on which Clarke is now engaged, the composi- 
tion of river water discharged into the sea, is also of great value. Wells's 
researches, such as his published "New determinations of carbon dioxide 
in water of the Gulf of Mexico" and the studies he is now making on the 
waters of Chesapeake Bay, are also of much value in understanding prob- 
lems of sedimentation, but the sediments themselves need to be studied. 
Richard Field of Brown University is studying some features of modem 
shoal- water limestones, and E. M. Kindle of the Canadian Geological Sur- 
vey is conducting important researches on modern limestones ; but Kindle 
may not be credited to the United States. 

Of the researches above enumerated, five deal with bottom samples and 
areal surveys of the sea bottom. The areas are the Bay of Maine, Chesa- 
peake Bay, southern Florida and the Bahamas, the mouth of Mississippi 
River, and San Francisco Bay. No one of these researches is progressing 
in a satisfactory way. Furthermore, all these researches deal primarily 
with shoal-water deposits — ^there is no work on deep-sea deposits. The 
only modern deep-sea samples recently described from America are two 
I described in 1917 from the Tongue of the Ocean, Bahamas. This, it 
seems to me, is a very poor showing for the United States. 

FACTORS THAT RETARD RESEARCHES ON SEDIMENTS 

During the period that the United States were participants in the 
World War, investigations on sediments suffered as did many other kinds 
of scientific work and our country has not yet finished its readjustment 
after the conflict. Besides the interruption caused by the war, several 
competent investigators have been diverted by other duties and a new 
crop of investigators has not yet ripened. 

The interruption of investigations and the diversion of investigators are 
not the only difficulties in the way of studies of sediments. The subject 
is one that does not belong exclusively in any one of the sciences as the 
sciences are currently classified, although those engaged in several kinds 
of scientific endeavor recognize the value of knowledge of certain aspects 
of it in the proper performance of some of their work. The engineer, 



88 PHYSICAL OCEANOGRAPHY 

for instance, wishes to understand shore-drift in certain places and the 
rate of the deposition of sediment in harbors; the student of fisheries 
wishes to know the relations between bottom materiafand organisms that 
may be used as food ; the navigator may keep his course through fog and 
snow by detailed knowledge of the bottom ; and the geologist may utilize 
knowledge of sediments in interpreting some geological formation of eco- 
nomic significance. Of the different kinds of scientific men the geologist 
is the most broadly concerned, because only by an adequate knowledge of 
the modern can he understand the ancient deposits and it is part of his 
work to study the mechanical features and the constituents of sediments, 
both modem and ancient, though he usually feels that his attention should 
be directed to past rather than to present history. This is a practical day 
and students inquire how they can make work on sediments pay. It has 
been possible to provide funds for some work on sediments but the re- 
muneration is far below that offered by oil companies. 

MEANS FOR PROSECUTING RESEARCHES ON SEDIMENTS 

In remarks already made I have tried to bring to your attention the 
present status of researches on marine sediments in this country and I 
have indicated some factors that I believe retard such investigations. How 
can the backward condition of researches in this important subject be 
remedied? I will venture a few suggestions. 

My first suggestion is that those interested endeavor to impress upon 
students the scientific importance of investigations on sediments. This 
may best be done by the establishment of courses in sedimentation in our 
universities and the offering of fellowships to graduate students for inves- 
tigations in the subject. At present courses in sedimentation are given at 
the universities of Wisconsin, Iowa, and California, and at the University 
of Iowa a research fellowship is maintained. Courses should be given at 
more universities and there should be more research fellowships. The 
Geophysical Union might combine with the divisions of Geology and 
Geography and of Biology and Agriculture and endeavor to establish two 
or three more fellowships in sedimentation. 

In addition to university work of the kind indicated an institution or 
institutions in which complicated special studies may be undertaken are 
needed. An institution comparable to the Geophysical Laboratory of the 
Carnegie Institution would fulfil the g^eat need but an endowment that 
will yield an income between $50,000 and $75,000 per year is not easily 
obtained. However, it is worth striving for. As such an institution does 
not exist it may be preferable to try to utilize existing institutions by ap- 
pealing to them and trying to strengthen them. The study of sediments 
is a fundamental of geology and the U. S. Geological Survey has recog- 
nized this and has tried to develop researches on sediments as a part of its 
wprk. Furthermore, many geologists, because of their training, are pre- 
pared to undertake such investigations. It is, therefore, suggested that 
those interested in such work make their desires known to the director of 



PHYSICAL OCEANOGRAPHY 89 

the U. S. Geological Survey, that it be pointed out to him how the Geo- 
logical Survey by doing such work can help science and serve other gov- 
ernmental bureaus, and that he be requested to do as much as the circum- 
stances of the Survey will permit. The Geological Survey has already 
done enough to place students of sediments under deep obligations to it. 
If it could study and prepare reports on bottom specimens one of the 
present difficulties in the way of advance in knowledge of marine bottom 
deposits would be removed. 

Until now it has been possible to obtain larger collections of properly 
taken bottom samples than it has been possible to study. The U. S. 
Bureau of Fisheries is fully equipped to collect samples precisely as they 
should be taken and the heads of that Bureau are anxious to do all they 
can to aid researches on sediments. Perhaps if provisions could be made 
to study the samples, the U. S. Coast and Geodetic Survey might make 
systematic collections. Other than governmental agencies, especially the 
Department of Marine Biology of the Carnegie Institution, have shown 
willingness to help in procuring bottom samples for study. The material 
available for investigation is large in quantity and much of it has been 
properly collected and is accompanied by all needed data. If these col- 
lections could be properly studied and reports on them published, what 
fine contributions would be made to our knowledge of marine sediments ! 

CONCLUSION 

In conclusion I wish to emphasize the value to science of a proper 
understanding of the marine sediments in the ocean of today. A proper 
understanding of these sediments includes knowledge of the depth, tem- 
perature, and salinity of the waters above them, the distance from shore 
to where they were deposited, their relations to currents, and if near land, 
the relief of the land, its climate, and the rocks composing it. Through 
such knowledge of modern sediments the criteria for interpreting the 
sediments of ancient seas are discovered. Having established the needed 
criteria, the boundaries of the old seas may be traced ; the physiography, 
constitution, and climate of the neighboring lands may be recognized, and 
the depth, temperature, chemical composition, and currents of the waters 
of the ancient oceans and the organisms that inhabited them may become 
known. Modem sediments, though important in understanding what is 
today, are doubly important because knowledge of them supplies the only 
key to what would otherwise be an unknown past. 



90 PHYSICAL OCEANOGRAPHY 



THE INTERVALS THAT SHOULD OBTAIN BETWEEN DEEP- 
SEA SOUNDINGS TO DISCLOSE THE OROGRAPHY 

OF THE OCEAN BASINS 

By G. W. LnTLSHALBS 

The intervals between sounding stations must be gauged by the dimen- 
sions of the orographical features whose presence it is intended to disclose. 
Leairing out of consideration details of topography and confining the 
attention to features of the greatest prominence, inquiry must be made 
as to the form and dimensions of the slenderest isolated submarine peak 
that could be raised from the floor of the ocean to a mountainous height 
and remain standing under the stresses of its own weight and of the 
superincumbent body of water. For if the spacing of soundings be such 
as to give indication of the presence of the slenderest form that could 
stand, then evidence of the presence of any orographical forms that may 
exist is likely to be afforded. Theoretically, the shape of an isolated 
submarine peak would be that of a solid of revolution in which the 
resistance to crushing of any horizontal section is equal to the combined 
weight of the portion of the formation above that section and of the 
superincumbent body of water. 

Let y denote the radius of any horizontal section and z its distance from 
the top of the formation. Let K denote the coefficient of resistance to 
crushing of the material composing the formation; w, the weight of a 
unit of its volume ; and w', the weight of a unit volume of sea water. 

Accordingly, irw f y*dz = the weight of the formation above any 

section whose distance from the top is z,2rw'fy,zAy—Tyr'jy*dz^ 

the weight of the water upon the formation above any section whose 
distance from the top is z, assuming the top of the formation to reach 
to the surface, xKy*— the strength of any section to resist crushing, and 

TW f y «dz + 2rw' f y .z .dy — rw' Jy'dz = xKy* ( 1 ) 

By differentiation, equation ( 1 ) becomes 

Twy*dz+2Tw'y.z.dy — irwV.dz = 2TK.y.dy (2) 

which expresses the condition that the increase of strength of any section 
in excess of that of the section next above is equal to the sum of the 
increases of the weight of the formation and the weight of the water 
upon any section in excess of their combined weight imposed upon the 
section next above. 



PHYSICAL OCEANOGRAPHY 91 

Letting S denote the area of any horizontal section whose radius is y, 
and dS, the differential of S, equation (2) may be written in the following 
forms: 

w.S.dz +w'.z.dS — w'S.dz = K.dS 
(w - wO S.dz = (K - w'z) dS 
dS_, « dz w— w' dz 

c- = (W-WO 



S ^'^ ^K-Vz w' K 



V-" 



By integration, equation (3) becomes 



log 



s.-— l„,(|-.)+c 



in which C is the constant of integration. 



(K \ w' w' 
-> — Z J = ; C ; log S 
w' / w— w' w— w' 



>c 



-, w— w 
K £ 



or "7 — z = 
w 



E 



{:^^<^^^) 



In the absence of knowledge of the value that should be assigned to K, 
the coefficient of resistance to crushing, this equation has been used in 
the generalized form, 

B B B . 

A— z = 



/ w^ , ^.\ / 1.03 , c\" £1-46 log loS 

to find the equation of their average form from the observed bathymetri- 
cal data on Seine Bank in latitude 33'' SCX N. and longitude W 20 W., 
Cocos or Keeling Island in latitude W 06' S. and longitude 96** 53' E., 
Enderbury Island in latitude 3** 10^ S. and longitude \7V 10' W., Funa- 
futi Atoll in latitude 8^ 25' S. and longitude 179** 07' E., Taviuni Bank 
in latitude 12' 05' S. and longitude 174** 35' W., and the shoal near Mid- 
way Island in the North Pacific Ocean in latitude 28** 00' N. and longitude 
177** 4a W. 

For this purpose the values of z and y, expressed in nautical miles, 
were inserted in the above equation, and a conditional equation was 
formed for each pair of coordinates relating to each of the submarine 
formations. From these conditional equations normal equations were 



92 



PHYSICAL OCEANOGRAPHY 




Fig. 1. Profiles of isolated submarine peaks. 



PHYSICAL OCEANOGRAPHY 93 

found by the method of least squares, which gave the values of the con- 

1.87 
stants A and B. The resulting equation is 1.87 — z = r-n >|>l6l Qg ^ 

and the corresponding curve, which by revolution around the vertical 
axis would generate the average form, is shown in figure 1, together with 
others which have been plotted for purposed of comparison from measured 
data. This investigation shows that isolated formations occupying com- 
paratively limited areas at the bottom can and do occur in the ocean 
depths, and we are able to assign at once the maximum interval that 
should obtain between deep-sea soundings taken in operations directed 
toward the development of the orography of the bottom of the sea. An 
interval of 8 miles coupled with a differential interval of 2 miles would 
serve for general development, and would prove with certainty the exist- 
ence or absence of any formation rising close to the surface. Of all the 
possible ways in which an 8-mile interval could lie with reference to a 
submerged peak, that which would be most advantageous for a prompt 
discovery of its existence is the condition in which one end of the interval 
is at the bottom of the slope and the other near the apex, and that which 
would be least advantageous is the condition in which the interval is bi- 
sected by the position of the apex. In the latter case, there would be 
nearly equal soundings at both ends, but the soundings at the ends of the 
adjacent two-mile intervals would in all probability give indication of the 
slopes.* 



^ Following the presentation of this paper the following suggestion was made by 
Harry Fielding Reid: 

Dr. Lattlehales' remarks about the soundings in the oceans bring up a matter that 
I have had in mind for some time; that is, the value of a detailed sounding of a 
single deep. We know very little indeed about the shape or conformation of the 
great ocean deeps ; a detailed set of soundings of a particular deep, to bring out not 
merely the general slope of the bottom, but also details of configuration, would be 
of great value. If, as seems probable, the great deeps are due to faulting, the sound- 
ings should be close enou^ together to show the existence of fault-scarps. A deep 
which offers especial facilities for such determinations is the Virgin Islands or 
Bronson Deep. It is a long east and west trough, lying a little north of Porto Rico, 
with a recorded sotmding of 4,662 fathoms (the greatest depth measured in the 
Atlantic) ; although but few soundings have been made in its deeper parts. Its 
situation is very convenient; San Juan could be used for a base for the western 
part and St. Thomas for the eastern part 

There are, of course, other parts of the Caribbean region where soundings would 
be valuable, but I think a detailed sounding of a single deep would yield more 
valuable results than scattered soundings over a larger area. 



94 PHYSICAL OCEANOGRAPHY 

NEW METHODS OF OBSERVING WINDS AT FLYING 

LEVELS OVER THE OCEAN 

By Alexander McAoie 

Aerography may be defined in a general way as a study of the structure 
of the atmosphere. There are various ways of obtaining information 
regarding the flow of air at different levels and the conditions of density, 
pressure, and temperature of the mixture of air and vapor. Exploration 
of the upper air has been accomplished by means of close study of the 
clouds; the establishment of mountain observatories; the ascent of 
manned balloons; kites and kite balloons; sounding balloons and pilot 
balloons. To these we propose to add another where measurement is 
made from the deck of a vessel by employing certain predetermined lapse 
rates, or rates of fall in temperature with elevation. 

The principle in brief is that provided sufficient water vapor is present 
and condensed as cloud, the height of the level of condensation is a func- 
tion of the lapse rate. The height can be obtained then from observations 
of the actual temperature, the temperature of evaporation and the tem- 
perature of saturation at sea-level, making proper corrections for surface 
speed and direction. 

It is a little more than twenty years since Teisserenc de Bort at Trappes, 
and Lawrence Rotch at Blue Hill, close friends and co-laborers, began 
the systematic sounding of the atmosphere by means of sounding balloons. 
With the war came a widespread use of pilot balloons. Today, sondages 
are made (or are supposed to be made) at all United States naval air 
stations, and at many land stations. During the war information regarding 
the speed and direction of the winds at flying levels thus obtained was 
of great value — not alone to the airmen, but also to artillerists and gas 
men. 

There is no special difficulty in using sounding balloons or pilot bal- 
loons on land; but at sea the sounding balloon is out of the question, 
owing to difficulty of recovering the record. Pilot balloons, however, can 
be used ; and during the trans- Atlantic flight of the N. C. boats, I obtained 
fully a hundred observations from sea-level up to 4 or 5 kilometers, while 
stationed on the U. S. S. Baltimore (mine layer). 

We can not, however, expect navigating officers of our merchant marine 
to send up balloons, follow them with theodolites, record the elevations 
and angles, plot the trajectories and deduce from these the speed in 
meters per second and the direction of motion for the different levels. 
Not but that it would pay to do so ; for it will pay any navigating officer 
to be posted concerning the structure of the air. It may sometimes mean 
the safety of the ship. And an intelligent aerographic officer with a 
moderate outfit of aerographic apparatus on a ship like the Mauretania 
could tell from the upper air movements studied in connection with the 
surface circulation, the location of the ship with reference to the true 



PHYSICAL OCEANOGRAPHY 95 

centers of gyratory and translatory flow, and could forecast the future 
path of the storm. A daily weather map or one at more frequent inter- 
vals, based on reports received by radio, could be made and used to great 
advantage with this added knowledge of the upper air conditions. 

In cloudy weather the pilot balloon may soon be lost and it is therefore 
advisable to substitute for the balloon method a method which makes use 
of clouds, especially lower clouds within 35 degrees of the zenith. Of 
course in dense fogs, neither method cajrbe used. 

The new method makes use of a specially stabilized nephoscope with 
automatic sighting rods, and an arc with tangent values ; also a new type 
of hygroscope. The combination may be called a marine altoscope. 

The nephoscope consists of a black mirror suitably mounted (for de- 
tails of construction see Blue Hill Report, 1910) to permit of motion in 
azimuth, proper leveling devices, and graduated circle, reading clockwise 
and in either degrees and tenths or in grads. To this mirror is attached 
a stabilizing device, suggested by Professor R. W. Wilson of Harvard 
University. The mirror thus keeps a horizontal position regardless of 
the ship's motion. 

A metal arc or quadrant springs from the plane of the mirror and is 
graduated in degrees, and also in natural tangents, the reason for which 
will appear later. 

At the free end of the arc a vertical rod is mounted and carries a panta- 
graph or diamond-shaped rectangle supporting two rods for sighting the 
cloud. Use is made of the reflection of the line joining cloud and eye, 
and the second sighting rod forms a straight line prolongation of the line 
from the center of the mirror to the cloud. The value of this is in fixing 
the eye, whatever the ship's motion may be. When once set, the eye can 
be withdrawn or rested for a few seconds and then brought back to the 
original position without delay or uncertainty. The radials can be pro- 
vided with sleeves permitting extension. 

In observing, first level the instrument. Bring the zero which is also 
360* or 400 grads of the horizontal or azimuth circle to the true south 
point. The circle is graduated clockwise and the true west will therefore 
be 100 if scale is in grads (90' if in ordinary units). 

Since the reflection of the cloud crosses the mirror in the same direction 
as the cloud is moving, the reading on the azimuthal circle where the 
cloud image passes off the black mirror will be the direction or angle 
from which the wind is blowing. 

The quadrant is now swung into position, making the same angle. With 
the control screw provided for the purpose of raising or lowering the 
sighting rods, bring the nearer sighting rod into perfect alignment with 
the reflection of the other sighting rod. This latter rod joins the cloud 
point and the center of the mirror. We have now the angular elevation 
of the cloud from a true horizon. When this angle is 50 grads or 45 
degrees, it is plain that the distance the reflection of the cloud moves in 
the mirror is equal to the height of the intercept corresponding to the 



96 PHYSICAL OCEANOGRAPHY 

height of the cloud; that is, the sine and cosine of the angle are equal, 
and the natural tangent is unity. 

In such a case, we have only to divide the height of the cloud (to be 
determined later) by the number of seconds to get the rate in meters 
per second. 

If, however, the cloud line does not make an angle of 45, we use directly 
the value of the tangents. The following condensed table gives these 
values : 

Tangent Grads Degree Tangent Grads Degree 



A = 24 


22 


.5 = 29 


26 


.6 = 34 


31 


.7 = 39 


35 


.8 = 43 


39 


.9 = 47 


42 


1.0 = 50 


45 


1.1 = 53 


48 


1.2 = 55 


50 


1.3 = 58 


52 


1.4 = 60 


54 


1.5 = 62 


56 



1.6 = 


64 


58 


1.7 = 


66 


59 


1.8 = 


68 


61 


1.9 = 


69 


62 


2.0 = 


70 


63 


2.5 = 


75 


68 


3.0 = 


80 


72 


4.0 = 


85 


76 


5.0 = 


87 


79 


6.3 = 


90 


81 


11.4 = 


95 


85 


00 


100 


90 



One has only to divide the height of the cloud by the arc reading (i. e., 
tangent value) to get the horizontal distance. This last divided by the 
number of seconds gives the speed of the cloud in meters per second. 
We thus have direction and speed of the air at the cloud level, provided 
the height of the cloud is known. 

To get the height we use a special t)rpe of psychrometer (McAdic 
cryoscope). The improvements over the usual psychrometers are: 

(1) The amount of air passing over the wet-bulb is under control; 
i. e., a definite value is given to the wind factor in evaporating the film 
of water. 

(2) The method of wetting the bulb is novel. The old method of usiii^ 
a wick or muslin cloth, bringing a constant supply of water by capillary 
action, is replaced by a fine metallic mesh shaped to slide over the bulb, 
easily wetted and containing a known small weight of water, to be evapo- 
rated in a given time. 

(3) The conversion of vapor pressure into units of force permits the 
use of a simple equation connecting the actual temperature, evaporation 
temperature, and saturation temperature. 

Of the above factors, the wind velocity is of great importance and must 
be known definitely if the humidity records are to be regarded as reliable. 
It may be pointed out that even in official meteorological services at home 
and abroad the records of relative humidity are open to criticism on the 
ground of uncertain ventilation. In the best forms of sling and whirling 
devices no record is kept of the time and number of revolutions. 



PHYSICAL OCEANOGRAPHY 97 

In the present instrument a definite wind velocity is automatically main- 
tained and the beginning and ending of the movement of the air over the 
evaporating surface, or what is approximately the same, the movement 
of the wet-bulb through the air, is definite. The wetted bulb can be swung 
either vertically or horizontally at any desired speed from 4 to 10 meters 
per second. The thermometers are carried by a frame which slides on the 
rod and their distance from the top of the rod or axis of rotation deter- 
mines the velocity of the equivalent wind. Thus at a distance of 100 
centimeters (39.3 in.) the bulb when whirled will travel in one complete 
revolution 6.283 meters (approximately 20 ft.). It is then only necessary 
to know the number of rotations and the time to get the speed of the wind. 
An automatic counter is so connected with the handle that at the comple- 
tion of every hundred revolutions an alarm bell rings. With a little 
practice one makes 100 swings per minute. 

If desired a watch may be used and the number of seconds counted. 
The rate mentioned, one hundred per minute, is equivalent to a wind of 
10.5 meters per second (23.5 miles per hour).^ 

Now, the rate of evaporation varies as the square root of the wind 
velocity. Thus the rate at 10.5 m/s is to the rate at 4 m/s as 16 to 10. 
The hygrometric tables in common use were based on experiments in 
which the speed of rotation was approximately 4.5 meters per second, 
although no definite statements are made and there appears to have been 
no special attention paid to the speed of rotation or the rate of fanning 
of the wet bulb. Naturally discordant results are obtained by different 
observers. The speed mentioned (4.5 m/s) is somewhat too low for a 
good circulation of air, and is indeed below the average wind value at 
most places. The value of 10 meters seems to be a more representative 
figure. 

In the present instrument the pressure of the water vapor at any tem- 
perature ordinarily met with above the freezing point is expressed in 
units of force, and so far as known this is the first instrument employing 
these units for water vapor. A kilobar is that pressure which if exerted 
as force would give an acceleration of one centimeter per second per sec- 
ond to a mass of weight one kilogram. Roughly, it is the pressure given 
by a wind of 12 meters per second on a plane one meter square and at 
right angles to the wind. Thus, temperature, pressure and weight are 
expressed in a uniform, consistent and scientific set of units, namely, the 

^ In the sling psychrometer used by the Bureau of Mines, if we assume a speed of 
100 revolutions per minute the equivalent wind would be about 2.9 m/s (6 miles per 
hour). There is no counting device and while a higher rate can be obtained, it is 
difficult to count by the eye more than 120 per minute. In the whirled psychrometer 
used by the Weather Bureau, the radius of rotation of the bulbs is about the same 
as in the Bureau of Mines instrument, but a geared handle permits of varying the 
rate from 175 to 260. The velocity equivalents will vaiy from 9 to 16 miles per 
hour, the rate of evaporation in the former being only 75% of that in the latter. 
McAdie has suggested a simple form of counter for this instrument to standardize 
the results and has used such a device at Blue Hill Observatory for two years. 



98 PHYSICAL OCEANOGRAPHY 

kilobar, kilograd, kilogram. These are strictly in accord wiA the C. G. S. 
system of um'ts. 

To determine relative and absolute humidities, and the temperature 
of saturation, the so-called dew-point, there is used an equation given 
by the author in the Physical Review, Vol. XIII, No. 4, page 285. 

in which p, is the pressure of the water vapor at the saturation or dew- 
point, p^ the pressure of evaporation — that is, the wet-bulb — p the pres- 
sure of the atmosphere expressed in kilobars, C a constant, t the tempera- 
ture of the dry-bulb expressed in kilograds, and t^ the temperature of 
the wet-bulb. 

When the wind velocity exceeds 2 m/s, pC may be written as 0.18 ; and 
for purposes of quick calculation we regard it as 20 percent without 
materially affecting the result. 

I stop at this point to read part of a letter just received from Sir Napier 
Shaw. He says : 

As to the inter-relation of meteorology and oceanography, I think that homidity 
probably offers the most promising line of attack, if we could be quite certain oi 
getting true humidities on board ship. I suppose that there must be a mathematical 
expression for the absolute humidity depending upon the air current and the eddy 
motion which it carries. I could imagine a very useful expedition tracing the in- 
crease in absolute humidity down the Trade Wind and ultimately to uie West 
Indies; but it is very difficult to get humidities on board ship because the dry bulb 
is apt to get wet and the wet bulb to get dry; and both of them to be spoiled by 
spray. But he will be a great benefactor who will give us a map of the distribution 
of absolute humidity over the Atlantic Ocean. 

Three things in the quotation are important : the suggestion of the map, 
the expression of belief in the humidity problem as a most promising 
liaison between meteorology and oceanography, and the remark about the 
difficulty of getting accurate humidities aboard ship. 

Granted, then, that we can get these humidity values at sea with much 
greater precision by these new instruments, we proceed to use these 
values in determining the cloud heights. 

The temperature of saturation can be obtained without the use of tables, 
which are always troublesome to use aboard ship, owing to high winds, 
from the cryoscope, or, if desired, from the accompanying chart (figure 2). 

An example will show how this is done. 

Let the dry reading be 1063 and the wet, after proper precautions, 
1053. The relative humidity is at once shown by the dotted line to be 
74, and the dew-point, obtained by running back to left-hand edge of chart 
parallel to the solid lines, 1046. If the absolute humidity is desired, one 
has only to follow the 1046 line horizontally to the right-«nd edge ; and 
one reads 1 1 grams per cubic meter of space. 

We will call 1046 the cloud point or temperature of condensation 
(heretofore called dew-point, but the new name has some advantages). 

What we now want is the difference between the surface temperature 



TEMPERATURE IN KILOGRADS 



Fig. 2. Absolute and relative huinidity 



PHYSICAL OCEANOGRAPHY 



Fig. 3. Cloud heights from surface hutnidtty 



PHYSICAL OCEANOGRAPHY 101 

axid the cloud levd ; or what may be caOed the depression of the cloud 
temperature (see figure 3). 1063 — 1046 = 17. The cloud height oppo- 
site 17 is 750 meters for a day of light winds and 600 meters for a 
windy day. A correction for percentage of saturation and type of struc- 
ture is desirable. 

I The height of the cloud being known, the direction and velocity are 

j obtained as described, and the observer can compare these values with 

the surface values. Nearly always there will be differences. In fair 
weather there is generally a steady shifting of the wind to a higher value 
for both speed and direction. At Blue Hill the mean deviation for the 
1000-meter level is 7 grads, or 6 degrees to the right. The increase in 
speed is variable, often 100 percent in the first 500 meters, and we have 
instances of 200 per cent. On the land we get all sorts of structures, in 
some of which, such as sea breeze, the depth of the surface flow is shallow 
and essentially different from the flow above. The values obtained by 
this nephoscope-cryoscope method are approximately gradient velocities 
and directions. It is possible to construct a chart when gradient velocity 
direction and latitude are known, from which the pressure gradient can 
be deduced ; and thus in a rough way the isolated observer could obtain 
the curvature of the isobar and pressure tendency. In former years this 
would have meant much ; but now, of course, full reports can be obtained 
by radio and the surface isobars easily drawn. 

It only remains to explain the variation in the value of the lapse rate 
on different days, or rather with different structures. 

While the adiabate rate is 35.5 kilograds per 1000 meters, an average 
rate of cooling of mixed air and vapor is 21 kilograds. 

For moist air saturated, a value of 18 may be taken. In windy weather, 
a fair value is 25 grads. 



PHYSICAL OCEANOGRAPHY 



THE STEERING LINE OF HURRICANES 
Bv ALSXAMnn UcAdik 

As a frontispiece to the "Manual of Meteorology," Part IV, "The ReU* 
tion of Wind to the Distribution of Barometric Pressure," Sir Napier 
Shaw gives three storm paths of unusual duration and remarkable re- 
curvature (see figure 4), 



Fig. 4. The tracks of some storms of long duration (after Shaw) 

Perhaps the most striking of these is a track of a typhoon or bagnio 
charted by McAdie. This storm path was determined by the usual method 
of connecting pressure minima. The readings were obtained from ab- 
stracts of ships' logs, available through the courtesy of the Hydrographtc 
Office. Surface winds and cloud directions were utilized as much as 
possible. 



PHYSICAL OCEANOGRAPHY 103 

It was agawimrd that the miniHHun pressure and the center of circula* 
tkm as indicated by surface winds were identical. It is, however* to be 
remembered that the wind direction as noted on the deck of a moving 
vessel may need correction. Fnrthermore the center of a cyclone is not 
necessarily the center of ascending air; and still further there must be in 
the convergence of the surface winds a certain distortion due to the travel 
of the storm. 

The storms referred to above are perhaps best described in the words 
of Sir Napier Shaw (page 119).^ 

There b evident stability in motion of this cfaaracler because beginning wtdi ex- 
amples of wliirb lasting for some seconds there is a^iparently an umntermpted 
sequence by way of rcvoivina sandstonns or dnst-devils, tornadoes, or whirlwinds, 
to tropical revolving storms and large cyclonic areas with radii of 10 degrees or 
more. 

The onty limit of the scries is a revolving air-cap covering the hemisphere or a 
large part of it And just as a belt of west wind or a belt of east wind may lie 
over dese [British] Isluids for weeks, so the other type of quasi-permanent atmos- 
pheric motion, which has always been diought of as a column of air in continuous 
revolution, may preserve its identity for days or weeks. Through the kindness of 
Professor McAdie of Blue Hill Observatory, Harvard University, we are enabled 
to give two notable examples. 

The first is that of a tropical revolving storm which started on a westerly track 
toward die Philippine Islands (where visitations of that kind are known as 
"Bagnios"), turned round toward the north and northeast, crossed the Pacific Ocean 
and, after some vagaries on the North American continent, continued its journey 
eastward and crossed the Atlantic in the usual track of cyclonic depressions over 
that ocean. The whole journey lasted from 20th November, 1895, to 22d January, 
1896. 

The second is a cyclonic depression of October, 1913, in the outer region of which 
the tornado was formed whidi caused so much destruction in South Wales on the 
27th of that month.* The track of the main depression shows an anomalous path 
from Canada to the north of the British Isles. [See figures 4, 5, and 6 from the 
"Geographical Review."] 

To these notable examples has been added the long track of cyclonic depression 
whidi was figured in the Meteorologiod Office chart of the North Atlantic and 
Mediterranean for August, 1904.' The cyclone was first noted on 3rd August, 1899, 
m that part of the North Atlantic Ocean where West Indian hurricanes often take 
their rise. It moved westward to the West Indies, skirted the coast of Florida and 
turned eastward over the Gulf Stream. After some hesitation about latitude 40* W. 
it made for the mouth of the English Channel and, missing that, crossed to the 
Mediterranean, where it lost itself on 9th September, after a life of thirty-eight days. 

In each of the above described storms it is evident that causes other 
than those developed by the rotating mass of air, operated to retard these 
storms in their eastward progress. 

Let us now trace the path of a West Indian hurricane where the evi- 
dence is seemingly more direct. 

On the morning of October 15, 1910, this storm was centered between 
Havana and Key West moving very slowly northward. The maximum 
wind velocity at the former place was 39.4 m/s (88 miles per hour) ; on 
the a. m. of the 14th; and at Key West 26.8 m/s (60 miles per hour). 



* See also ** Wandering Storms," McArdie, Geographical Review, 10, no. I. July, 

1920. 

* Geophysical Memoirs, no. 11. M. O. Publication, no. 22a. 

* M. O. Publication, no. 149. 



PHYSICAL OCEANOGRAPHY 



Fic. 5. Track of storm of September 27-October 28, 1913. 



PHYSICAL OCEANOGRAPHY 105 

The stoim's progress northward was checked by a continental area of 
high pressure moving southward. Thus on the 17th we find the hurricane 
actually retrograding and centering again over Havana. As the conti- 
nental anticyclone moved east, the hurricane developed a northerly com- 
ponent of motion and on the 18th moved across Florida. It then fol- 
lowed the usual hurricane track passing south of Cape Hatteras on the 
20th. The hourly speed increased from 30 kms. to 50 kms. per hour and 
the direction of motion 40 degrees east of north. 

The speed continued to increase averaging 60 kms. per hour and the 
direction shifted more to the east, approximately 65 degrees east of north, 
and so at noon of October 21 the center was in the latitude 37 degrees 
north and 67 degrees west. 

Professor Bjerknes has remarked that "anticyclones are bom as 
cyclones die" but the behavior of this and similar storms gives the impres- 
sion that the path and speed of West Indian hurricanes, off the coast of 
Florida, are dependent upon the intensity and direction of advancing 
highs. These in turn may be but the surface expression of an advancing 
polar front. 

Two types of south moving sub-Arctic surges which seem to control 
the path of hurricanes from the Caribbean Sea to the North Atlantic can 
be identified. The first of these is a Nichikun high. This is a more appro- 
priate designation of what has heretofore been known as a Labrador high. 
According to Dr. Klotz * there is nowhere else in Canada "so distinct a 
Pamir or Roof of the World as the neighborhood of Lake Nichikun (in 
English, Otter Lake)." The lake itself is in latitude 53* N., longitude 
71** W., and on the northwest slope of the Height of Land. The drainage 
is into Hudson Bay. On the south and east the drainage is into the River 
St. Lawrence. It is this southern slope which concerns us because south 
moving masses of air pass over the ridge, elevation 730 meters ; and being 
both cold and dry and therefore heavy, fall to sea level in a comparatively 
short distance, 200 to 600 kilometers. 

The other type of sub- Arctic surge is the "Labrador," essentially 
oceanic. 

Both of these tongues may be portions of what Bjerknes has called the 
polar front. They undoubtedly play an important part in determining 
the speed and path of storm centers in the North Atlantic States and effec- 
tively control the path of tropical storms or hurricanes as they move from 
the south and change into North Atlantic cyclones. 

On the Pilot Chart of the North Atlantic Ocean for October, the path 
of the hurricane under discussion ends abruptly in the position and on 
the date given above (Oct. 21). One might in consequence infer that the 
storm dissipated at sea. 

Careful study of pressure conditions shows a depression on the 22d in 
latitude 35** N. and longitude 60** W. A day later it appears as one of 
two centers in a large depression extending from New Brunswick to 



* In a letter to the writer. 



PHYSICAL OCEANOGRAPHY 



PHYSICAL OCEANOGRAPHY 107 

Bennada. The other center can be traced back to a storm over Lake 
Superior on October 21. The previous history of this depression, while 
somewhat obscure, is deserving of study. It appeared as an unexpected 
abnormal devel(qmient and invalidated all forecasts made for the Lake 
R^on, Upper Mississippi and Ohio Valleys. Where cold weather, frosts 
and an absence of precipitation were reasonably anticipated from an ad- 
vancing high pressure (1030 kb.), there suddenly developed warmer 
weather with rain. On the face of the map we are unable to connect this 
low with a more northern slow moving depression of the Alberta type. 
The weather map of October 20, 1910, will repay study in connection 
with the steering line of cyclones. 

To return to the hurricane and its further history, we have seen that 
when centered over Florida, there were in juxtaposition two air masses 
of different origin, one from the tropics with a vapor content of not less 
than 20 grams per unit volume (one cubic meter of space) and an average 
northwest speed of one kilometer per hour, while the other air mass was 
of sub-polar origin, approximately 20 kilograds (5.5 degrees C.) colder, 
and with an average vapor density of 12 grams per cubic meter. The 
densities of the two air masses at a pressure of 1 megabar would be 
approximately 1170 and 1220 grams. Air motion is initiated by differ- 
ence of pressure rather than difference of density ; but it is plain that the 
south moving air mass would continue to gain momentum and underrun 
the less dense northbound air. The horizontal pressure gradient was 
1 kb./20 km. and hence surface velocities of 30 meters per second or 
higher would and did occur. The gradient velocities were 23 m/s or 
higher ; and the radii of survature of isobars approximately 100 kilometers. 

Figure 7 shows the path of the hurricane from October 13 to 25, and 
also the path of the lake "low" from October 21 to 24. Other charts 
show the surface pressure distribution on various dates. 

It is much to be r^^etted that there are no records of winds aloft. 
When such data shall be available then perhaps definite relations between 
path, velocity and duration of hurricanes with upper' winds will be forth- 
coming. 

Recently it has been claimed by meteorologists of the Bergen (Norway) 
Institute that the storms of the Northern Hemisphere can be traced back 
to a "surface of junction of polar and equatorial air." This surface can 
be detected at the ground as "a line of discontinuity" in surface condi- 
tions. In other words, it is the boundary between air masses of different 
densities, pressures, and vapor content. 

(jiven then a mass of warm moist air moving north of east, under the 
combined effects of general drift, pressure gradient and rotational deflec- 
tion, and a second mass of cold dry air moving south, the surface of dis- 
continuity should be detectable as a moving front. 

Professor Bjerknes has come to the conclusion from the study of the 
structure of moving cyclones that a broad belt of rain accompanies the 
moving (and ascending) warm moist air, and a second smaller rain belt 



108 PHYSICAL OCEANOGRAPHY 

follows, where cold dry air underruns the warm air, that is, along the 
wind shift or squall line. 

A more important point, however, is the discovery through the use of 
detail maps, that the discontinuity or contrast can be traced from any 
cyclone to another. As expressed by Bjerknes, ^dones follow each other 
along a common line of discontinuity like "pearls on a string/' 

Furthermore this line of discontinuity surrounds the polar regions as a 
closed circuit. It shows how far the cold air flowing along the ground 
has penetrated. Shaw describes it as a kind of polar front Hne.^ 

The following substance of the discussion at the Meteorological OflSce 
on "new methods of forecasting" may make plain the leading features of 
Bjerknes's views.' 

In the case of a cyclone making progress towards tfie east, a sector to the south 
is occupied by a warm current; this warm area on the earth's surface is bounded 
to the north by the "steering line," to the west by the "squall-line." Bjerknes' 
generalization is "that these squall-lines and steering lines of all the cyclones of 
Sie northern hemisphere are parts of a single line — *the polar front'" We are to 
think of two great streams of air, both flowing from the west, the more northerly 
stream being colder and carrying less moisture. The boundary between these two 
streams is imstable and its oscillations manifest themselves as cyclones. The warm 
stream overrides Uie cold one, which retaliates, so to speak, by turning round and 
kicking its partner in the back. 

Charts 4, 5 and 6 are reproduced through the courtesy of the Geo- 
graphical Review, published by the American Geographical Society, New 
York City. 

^ Nature, January 24, 1920, p. 524. 

* Meteorological MagoMme, November, 1920, p. 213. 



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Vol. 3. Part 3. AUGUST, 1922 Number 18. 



Bulletin 



OF THE 



National Research 

Council 



THEORIES OF MAGNETISM 

Report of the Committee on Theories of Magnetism of the 

National Research Council 



BT 



A. P. Wills^ S. J. Barnett, L. R. Ingersoll, J. Kunz^ S. L. Quimby, 

E. M. Terry, S. R. Williams 



PUBUBHED BY ThB NATIONAL ReSEABCH COUNCIL 

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1922 



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PREFACE 

The present report attempts to sketch in bold outline the evolution 
and development of magnetic theories from the time of Poisson and 
Ampere to the present, including some reference to experimental results, 
particularly in the domain of magnetostriction where theory and ex- 
periment are in the greatest need of reconciliation. 

It will be noticed that the table of contents for the complete report 
does not contain any reference to the HaU Elffect or allied phenomena. 
The reason for this omission is that these topics have been assigned by 
the National Research Council to another committee. 

Space limitations have debarred from inclusion in the report some 
material which appropriately might have found place there. Certain 
portions of the subjects treated may have been emphasized more than 
their importance deserves, while others have been unduly slighted. 
The report, being a composite compilation by contributors so widely 
separated geographically that close collaboration was not always pos- 
sible, may lack somewhat in coherency. 

But in spite of such deficiencies it is hoped that the report may furnish 
a perspective of the subject which in its chief outlines is reasonably free 
from distortion and that the reader may obtain from its perusal a fair idea 
of the present status of magnetic theory. 

The committee is indebted to Professor L. R. Ingersoll of the Univer- 
sity of Wisconsin for his contribution on Magneto-optics. 



i 



BULLETIN 

OF THE 



NATIONAL RESEARCH COUNCIL 

Vol. 3. Part 3 AUGUST. 1922 Number 16 



THEORIES OF MAGNETISM 

Report of the Committee on Theories of Magnetism of the 

National Research Council^ 



CONTENTS 

Magnetic theories prior to the discovery of the electron. By S. L. Quimby 3 

Theories of para- and of diamagnetism. By A. P. Wilis 16 

Theories of ferromagnetism — ^intrinfiic fields. By E. M. Terry 113 

Theories of magnetic crystals and the magneton. By J. Kuns 165 

Magnetostriction and its bearing on magnetic theories. By S. R. Williams 214 

Theories of magnetostriction. By S. L. Quimby 225 

The angular momentum of the elementary magnet. By S. J. Bamett 235 

Magneto-optics. By L. R. IngersoU 251 



MAGNETIC THEORIES PRIOR TO THE DISCOVERY OF 

THE ELECTRON 

Bt S. L. Quimbt 

Instructor in Physics, Columbia University 

THE BEGINNING OF THE SCIENCE OF MAGNETISM. GILBERT'S 

"DE MAGNETE" 

The science of magnetising as well as of electricity, began with the re- 
searches of William Gilbert (b. 1540, d. 1603). The ancients were ac- 
quainted with the fact that amber, when rubbed, attracts light bodies, 
that the lodestone has the power of attracting iron, and that this power 
can be conmiunicated to the iron by bringing it near to or stroking it 
with a lodestone. The latter had been used as a mariners' compass at 
least since the time of the Crusades. No attempt had been made, how- 
ever, to order or extend the small amount of available knowledge con- 
cerning these phenomena. Rather was it lost in a mass of false doctrine 
bmlt about it by the medical profession, who were chiefly interested in 

^ This oonmiittee of the Division of Physical Sciences of the National Research 
Council consists of the following members: A. P. Wills, Columbia University, Chair- 
man; S. J. Bamett, Carnegie Institution; J. Kuns, University of Illinois: S. L. 
Quimby, Columbia University; E. M. Terry, University of Wisconsin; S. R. Williams, 
Oberlin College. 

3 



4 EARLY MAGNETIC THEORIES: QUIMBY 

utilizing the mysterious property of the lodestone for the curing of 
disease. Gilbert, himself a physician, dissipated these erroneous 
notions by clearly separating the medicinal from the magnetic properties 
of the lodestone, and then proceeded with an exhaustive investigation of 
the latter. 

He differentiated sharply between electrical and magnetic attraction 
by pointing out the difference in behavior of electrified amber and mag- 
netized iron. He emphasized the dual nature of the magnetic element 
and examined the effect of the shape of a magnet upon its strength. 

After pointing out that the earth is itself a huge magnet, Gilbert 
investigated the variation and dip of the magnetic needle over its surface 
and coordinated a vast mass of data which he secured from mariners. 

Apart, however, from the intrinsic worth of Gilbert's researches, his 
work may be regarded as the forerunner of the modem scientific method. 
His De Magnete (1600)^ contains the first formulation of natural law 
based entirely upon the results of experiment. In it Gilbert applied 
the method which was later set forth with logical precision by Francis 
Bacon. 

No material advance upon the knowledge of magnetic phenomena 
recorded in GUbert's book was made for nearly two centuries. During 
this period developments along different Unes were taking place which 
eventually made possible the great progress in magnetic theory which 
marks the nineteenth century. One of these was the improvement of 
methods of experimentation. With the fundamental importance of the 
experimental method once definitely established advancement along 
this hne reached a point where Coulomb in 1785 was able to prove 
satisfactorily the inverse square law of magnetic attraction and repulsion. 

Another important factor in scientific progress about this time was 
the rapid growth of mathematical analysis which followed the discovery 
of the infinitesimal calculus by Newton and Leibniz. Under the in- 
spiration of Laplace, Lagrange, and Legendre, mathematicians, par- 
ticularly Poisson and Fourier, about the beginning of the nineteenth 
century began to apply mathematical analysis to physical problems. 
In 1812 Poisson published a memoir on electrostatics and in 1820 
another on the theory of magnetism which remains to the present day a 
correct mathematical formulation of the phenomenon of magnetic 
induction.^ 

POISSON'S THEORY OF MAGNETISM 

The starting point of Poisson's mathematical theory is Coulomb's 
law that two magnetic poles attract or repel each other with a force 

> EDgliah traoBlation by P. Fleury Mottelay; New York, John Wiley and Sons, 1893. 
*PoiB8an, "Sur la Theorie du Maenetisme," M^moires de I'lnstitut, V (1820), p. 
247 and 488. 



EARLY MAGNETIC THEORIES: QUIMBY 5 

inversely proportional to the square of their distance apart. As a 
mechanism for the utilization of this principle he adopted the "two 
fluid'' theory of magnetism which had been previously advanced by 
Coulomb and others. In accordance with this theory Poisson assumed 
that all magnetic substances consist of a large number of small particles 
or magnetic elements containing equal quantities of positive and negative 
magnetic fluid. These elements are themselves perfect conductors for 
the fluids, but the spaces between them are impenetrable to the fluids, 
which cannot be allowed to pass from one element to another. In the 
unmagnetized state of the body the two fluids are united to form a single 
neutral fluid. The process of magnetization consists in the separation 
of the two fluids within the magnetic element, one being displaced in 
one direction under the action of the magnetizing force and the other 
in the opposite direction. 

In applying Coulomb's law to calculate the interactions between 
these magnetic elements, Poisson assimied that the force of repulsion 
exerted by a quantity, qi, of magnetic fluid upon a quantity, qs, of the 
same kind situated a distance r from it, is proportional to 



and is independent of the substance of which the magnetized body is 
composed. 

Using this conception of the phenomenon of magnetization Poisson 
solved the problem of calculating the magnitude and direction of the 
resultant force exerted by a magnetized body of any shape upon a imit 
magnetic pole situated at any point outside the body. He exhibited 
this force as the negative gradient of a function V, which may be ex- 
pressed as follows: 



= j - (I- n) dS - j - (div I) dr. 



s 

where n is a unit normal to an element dS of the surface S bounding a 
magnetized body of volume t. I is a vector such that if 5r be any 
physically small element of volume within the body, then Br will be 
the magnetic moment of that element of volume. It is therefore the 
"intensity of magnetization" of the substance at a point within 5r. 
The form of the fimction V shows that the magnetic effect of any mag- 
netized body is the same as that which would be produced by a layer of 
magnetic fluid of density I-n over its surface, together with a distri- 



6 EARLY MAGNETIC THEORIES: QUIMBY 

bution of density — divl throughout its volume. These are called 
''Poisson's equivalent surface and volume distributions of magnetism/' 

It is evident that for points inside the magnetised body r^^ will become 
infinite for an element of the second integral in Poisson's expression. 
This difficulty may be removed if we consider the point situated inside 
a cavity in the medium, small in dimensions, yet very large compared 
with the dimensions of the elementary nuignets themselves.^ A part of 
the surface density I- n will be on the wall of the cavity and this part 
will give rise to a finite force at the point inside it, whose value will 
depend on the form of the cavity and on the magnetic polarisation at 
the place. If we omit this purely local part of the magnetic force in 
the cavity, the remaining part, which is that due to the polarised mass 
as a whole, will be derived from the general volume density div I and 
surface density I* n just as at an outside point. This latter part arising 
from the system as a whole, omitting the local term depending on the 
molecular structure at the point considered, is thus quite definite, and 
is named the magnetic force H. In this way we arrive at a definition 
of the magnetic force within a magnetised medium which is consistent 
with the way it is defined for points external to the substance. 

Though the h3rpotheses regarding the nature of the magnetic element 
which Poisson adopted have not proved to be correct, the formuls of 
magnetostatics which he developed remain valid and useful since they 
rest upon the experimental fact of induced nuignetization and not upon 
the nature of the mechanism by which this is brought about. 

The mathematical labor of developing a complete theory of magnetic 
induction foimded solely upon experimental data was later undertaken 
by Lord Kelvin. In addition to freeing Poisson's theory from the hy- 
pothesis of two magnetic fluids, Kelvin greatly enriched it and simplified 
the conceptions involved by introducing the terminology which is used 
today.* One such extension in particular should be mentioned here. 

Poisson had pointed out that in general the intensity of magnetisation 
in a homogeneous body is a linear vector function of the field intensity, 
so that in general the specification of I in terms of H would require 
nine constants depending upon the nature of the substance. If the 
medium be isotropic as well, these nine constants reduce to one, so that 
for this case: 

I»kH. 

The subsequent researches of Faraday, Pllicker and Tyndall having 
revealed the fact that crystals possess different magnetic properties in 
different directions, Kelvin extended the theory to a treatment of the 

1 ef. Larmor. "Aether and Matter," p. 257. 

t KelTin, "Reprint of Papers on Electrostatiot and Magnetism/' XXIV. 



EARLY MAGNETIC THEORIES: QUIMBY 7 

problem of magnetic induction in non-isotropic media. He showed^ 
that for such media the nine constants introduced by Poission reduce 
to three, so that: 

in which the linear vector function # is self-conjugate. 

As it has been handed down to us by Poisson, Green, and Kelvin, the 
mathematical theory of magnetic induction may be regarded as com- 
plete. It is inadequate to meet the demands of the modem viewpoint 
because it is essentially a statistical theory. It deals with the phenomena 
exhibited by matter in bulk, without attempting to account for the 
ultimate causes of these phenomena. Just as Thermod3mamics pre- 
ceded Kinetic Theory, so the theory of magnetostatics has preceded a 
study of the dynamics of the ultimate magnetic particle. 

AMPERE'S THEORY OF MAGNETISM 

In July 1820 Oersted announced the discovery that a magnetic needle 
placed near a conductor carrying an electric current tends to assume a 
position at right angles to the conductor. This discovery inspired 
Ampere to imdertake a series of researches on the relation between 
current electricity and magnetism which extended over a period of three 
years and resulted in the publication in 1825 of a memoir on the mathe- 
matical theory of electrodynamical phenomena which has been charac- 
terized by MaxweU as, ''one of the most brilliant achievements of 
science."^ 

Ampere based his theory of magnetism upon the identity which he 
established between the magnetic properties of Poisson's "two fluid" 
magnetic element and a solenoid of molecular dimensions in which an 
electric current is continually flowing. According to Ampere the 
molecules of a magnetic substance are perfect conductors about which 
or within which are flowing perpetually minute currents of electricity. 

The process of magnetization consists in changing the orientation of 
these molecular currents either by changing the plane of the current 
relative to the molecule, or by turning the molecule as a whole, so that 
their axes, initially pointing in all directions at random, wiU tend to 
align themselves parallel to the magnetizing field. . Ampere showed 
that this sort of magnetic element would suffice to explain not only the 
phenomena of magnetostatics in accordance with the formulse deduced 
by Poisson, but also the laws expressing the mutual actions of magnets 
and conductors carrying currents, which had been discovered by Biot, 
Arago, and himself. 

1 ibid. XXX. 

«Ampere, ''M^moim de rinstitut." VI (1823), p. 175. 



8 BARLY MAGNETIC THEORIBS: QUIMBY 

At the time at which Ampere wrote, electromagnetic current induction 
had not yet been disooveredy and therefore he was able to make no 
h3rpothe6i0 as to the origin and strength of the molecular currents. 
Ampere's great contribution to the science of magnetism consisted in 
showing that all the then known interactions between magnets, and 
between these and electrical conductors, could be reduced to a single 
cause. 

THE MAGNETIC RESEARCHES OF FARADAY 

The fact that an electric current is invariably accompanied by a 
magnetic field led Faraday to search for a converse effect.^ 

In a paper read before the Royal Society in 1831 he described a series 
of experiments in which the phenomenon of electromagnetic current 
induction was discovered. The establishment of this reciprocal relation- 
ship between magnetism and current electricity afforded added support 
to the molecular current h3rpothesis of Ampere as against the two 
fluid theory of Poisson. Another discovery by Faraday, however, 
sufficed to clinch the argument in favor of Ampere's theory and to 
demonstrate that of Poisson to be untenable. 

In 1845 while investigating the rotation of the plane of polarization of 
a beam of light traversing a piece of glass placed in a strong magnetic 
field, Faraday observed that the glass itself possessed magnetic proper- 
ties opposite to those of iron and other "magnetic" metals.* While a 
piece of iron would tend to set itself with its greatest length parallel to 
the field, the glass, if left free to turn, placed itself across the field. 
Faraday gave the name ''diamagnetism" to this new phenomenon, 
and proceeded to make a thorough examination of the magnetic proper- 
ties of a vast number of substances, solids, liquids and gases. He 
definitely established the fact that all substances possess either the 
diamagnetic or the magnetic property. He even concluded that, 
"If a man could be suspended, with sufficient delicacy, and placed in 
the magnetic field, he would point equatorially, for all the substances of 
which he is formed, including the blood, possess this property." 

In accordance with the two fluid theory of magnetism, the elementary 
magnets of all substances would, when placed in a magnetic field, be 
polarised in the same direction. Faraday showed, however, that the 
direction of polarization of diamagnetic bodies in a magnetic field is 
opposite to that of noagnetic bodies in the same field. The two fluid 
h3rpothesis, therefore, fails in this respect to account for the facts. 

Adopting Ampere's theory, a substance whose molecules were them- 
selves elementary magnets due to the existence of permanent electric 
■ ■ ■ ' ' ' — — — >r . 

> Faraday, Eiperimantal R eaearchae, I, p. 2. The diamagnetic property of Biamuth 
had prevYoualy been observed by Brugmana. 
• Faraday* op. dt.. III. p. 27. 



EARLY MAGNETIC THEORIES: QUIMBY 



9 



currents JSowing about them, would be magnetic. On the other hand, 
if no such currents existed initially, then the action of an applied mag- 
netic field might induce such molecular currents, and these, by Faraday's 
law of current induction, would polarize the molecule magnetically in 
opposition to the external field : that is, the substance would be diamag- 
netic. 

In 1852 Wilhehn Weber, adopting Ampere's h3rpothesis and the results 
of Faraday's researches, developed mathematically a theory which it 
will be profitably to outline here in some detail, for it laid the foundation 
for certain of the modem theories of magnetism. 

WEBER'S THEORY OF MAGNETISM 

Weber starts by assuming that the molecules of a magnetic substance 
are small permanent magnets whose axes in- 
itially point in all directions at random.^ Let 
NM (Fig. 1) be such a magnet, which is 
capable of turning about its center C, under 
the action of an external field H. If the 
molecule were perfectly free to rotate then 
the body would be magnetized to saturation 
by any applied field, however small. This 
Weber knew was not the case, and he there- 
fore assumed a constraint upon the rotation 
of the elementary magnets in the form of a 

molecular nuignetic field, D, whose direction for each molecule coincides 
with the initial equilibriimi position of its axis, and whose magnitude is 
constant throughout the body. 

The magnet will be in equilibrium imder the action of the two fields 
when 

_ Hsing (1) 

^*""D + Hcos«' 

If M denote the magnetic moment of the molecule, its component parallel 
to H is, before the application of the field, 

fACOBd 

which, upon the establishment of the field, becomes 

M cos (^ — ^). 

Hence the increase in the magnetic moment parallel to H, say Mb> 
due to the presence of the external field is given by: 




Fig. 1 



Mh 



■'{ 



cos (^ — ^) — cos ^ 



}• 



(2) 



> W. Weber, " Uber den ZuBammenhang der Lehre vom Diamngnetiamua mit der Lehre 
▼on dem Magnetismus und der Elektrioit&t," PogO' Ann. 87 (1864), p. 146. 



10 EARLY MAGNETIC THEORIES: QUIMBY 

Eliminating 4> between equation (1) and (2) we have for a aingle molecule : 

( H + D cos ^ ) 

This expression must now be summed for all the molecules imder 
consideration. Let there be n molecules per unit volume. Assiuning 
initially a random distribution of the axes in space, the fraction of the 
molecules whose axes make an angle less than 6 with H will evidently 
be the ratio of the area of the zone cut from a sphere by a cone of semi- 
angle 0, to the area of the sphere, that is }4{l — cos 6). The number 
of molecules whose axes make angles with H lying between 6 and 
$ + dSis, therefore, 

The net increase in the magnetic moment per unit volume due to the 
rotation of all the elementary magnets is, then, given by: 



\J i 



Mh sin ^ d^. 



2 H 

If H < D this integral has the value I = q M n fi' 

2m n 

Tf IT la D " " " " " I ^ - • 

If H > D " " " " " I = M n 



\ 3BP/ 



If H = 00 " " " " " I = M n. 

An examination of these formulae shows that the intensity of 
magnetization should increase proportionally to the impressed field 
until it has reached ^ of its maximum value, after which it should 
approach the latter as3rmptotically. Weber obtained experimental 
results for iron in close agreement with this conclusion. His theory, 
however, is unable to account for residual magnetism, and more accurate 
experiments have shown that the initial variation of intensity of 
magnetization with field strength is not linear. 

Before proceeding to a discussion of the various modifications which 
have been suggested to resolve these discrepancies, we will review briefly 
Weber's theory of diamagnetism. 

According to Weber's theory, there exist in the molecules of a 
diamagnetic substance closed channels in which electricity can flow 
without resistance. If a magnetic field is established through one of 
these channels an electric current will be set in motion in it. The 
magnetic field of this induced current will be opposed to the external 



EARLY MAGNETIC THEORIES: QUIMBY 11 

field. In the mathematical development of his theory Weber made use 
of electrodynamical formulae derived from assumptions regarding the 
nature of current electricity which have since been abandoned. It will 
therefore be more profitable to examine the theory in the form in which 
it was afterwards interpreted by Maxwell.^ 

If L is the coefficient of self induction of a molecular circuit, and M 
is the coefficient of mutual induction between this circuit and some 
other circuit, and if, furthermore, i is the current in the molecular 
circuit, and i' that in the other circuit, then: 

~ (li + MiO = ~ Ri. 
dt 

But by h3rpothesis R = O, and we get by integration : 

li + Mi' = lio, 

where io is thus the initial value of the molecular current. 

If the current i' produces a magnetic field of strength H which makes 
an angle 6 with the normal to the plane of the molecular current, then : 

Mi' = HA cos e, 

where A is the area of the molecular circuit. Hence : 

li + HA cos ^ = lio. 

Diamagnetic substances dififer from magnetic in that in the former 
there are no permanent molecular currents. Hence for diamagnetic 
substances io »0, and we have for the value of the induced current: 

HA ^ 

1 = z- COS 0. 

Li 

The magnetic moment, /i^ of this current is expressed by: 

HA* 

M = iA = — cos 0; 

L« 

and the component of this parallel to H by 

HA« 

M cos ^ — COS* 0. 

Lt 

If there are n such molecular currents per unit volume with their axes 
distributed at random, the number of axes lying between and + 

d0 will be, as before, - sin d d0. 

Hence the resultant magnetization per unit volume will be given by: 

HA* 



-/: - °- 



2L 
1 n H A* . 
3 L 



cos* $smed$ 



> Maxwell, Treatiae II, §838. 



12 EARLY MAGNETIC THEORIES: QUIMBY 

and the diamagnetic susoeptibility per unit volume becomes: 

^ 3 L 

It is evident that Weber's theory of diamagnetism offers a satisfactory 
fundamental explanation of the phenomenon provided that his assump- 
tion of the existence of perfectly conducting channels about the 
molecules be granted. This assumption, however, did not appeal 
strongly to his contemporaries, as is evident from a remark by Tyndall 
in the Bakerian Lecture for 1855 that, ''This theory, notwithstanding 
its great beauty, is so extremely artificial, that I imagine the general 
conviction of its truth cannot be very strong." 

The discovery of the electron fiunished an adequate mechanism for 
the verification of Weber's h3rpothesis, and some of the more recent 
attempts to explain diamagnetism are nothing more than efforts to fit 
this mechanism into the fundamental theory which Weber established. 

MAXWELL'S MODIFICATION OF WEBER'S THEORY 

It has been noted that Weber's theory fails to account for residual 
magnetism. MaxweU introduced a new assumption designed to re- 
move this deficiency by providing for a permanent alteration in the 
position of equilibrimn of a molecular magnet.^ He s«ippo8ed that if 
the deflection of the magnetic axis of a molecule under the action of 
a magnetizing field is less than some fixed value /So, then it will return 
to its original position on the removal of the deflecting force. If, 
however, the deflection, /3, is greater than /So, then, when the external 
field is removed the magnetic axis of the molecule^ will not return to 
its initial position but will remain permanently deflected through an 
angle /S-/3o. Incorporating this hypothesis into Weber's theory leaving 
the remainder of it unchanged, MaxweU obtained theoretical magneti- 
zation curves which exhibit the phenomenon of retentivity. But 
while the main hysteresis loop of a ferromagnetic substance may be 
roughly accounted for in this way, the modified theory fails to explain 
the smaller loops which may be superimposed on this by only partially 
removing the magnetizing field and then reapplying it. Furthermore, 
a physical justification for the assumption of the critical angle /So as 
well as for the controlling field D of Weber's theory seems to be lacking. 

Maxwell made a further extension of Weber's theory by investigating 
the diamagnetic effect which is, on the hypothesis of molecular currents, 
sure to be present in all magnetic substances. 

In the molecules of such substances the primitive current, io, will 
be diminished by the action of the applied field so that we have, in 
accordance with the analysis of the previous section, 

1 Maxwell, op. dt., S4i4« 



EARLY MAGNETIC THEORIES: QUIMBY 13 

. . HA ^ 

1 =» lo — COS 6. 

JL 

The magnetic moment of the molecule is given by: 

•A • A HA« ^ 

/I ^^ lA = loA — cos $, 

L 

and its component parallel to H by: 

HA« 

M cos ^ = ioA cos =— cos ^d 

JL 



=" ioA cos ^ 



/. HA« \ 



HA 

If — - is small compared with unity, /i = ioA, and we return to Weber's 

HA 

theory of magnetism. If — is large compared with unity, then 

HA« ^^"^ 

M = r— cos* 6, and Weber's theory of diamagnetism foUows. It is 

L« 

evident that the greater the value of io, the primitive value of the 
molecular current, the smaller will be the diamagnetic effect. More- 
over, a large value of L will bring about the same result. In any 
event, it follows that the intensity of magnetization should diminish 
if the impressed field be made sufficiently great. Such an effect has 
not been observed, but it is evident that it wiU be very small and the 
experimental difficulties which must be overcome in order to detect it 
correspondingly great. 

EWING'S THEORY OF RESIDUAL MAGNETISM AND HYSTERESIS 

The accurate and extensive researches of H. A. Rowland^ and others 
definitely established the inadequacy of existing theories to explain 
h3rsteretic phenomena in iron and other ferromagnetic substances. In 
attacking the problem Ewing discarded the arbitrary postulates re- 
garding the controlling field and angle of. permanent set, and endeavored 
to account for the magnetic behavior of these substances by investigating 
the effect of the constraint which the molecules exert upon one another 
by reason of the fact that they are magnets.' 

Consider, for simplicity, a group consisting of two equivalent mole- 
cular magnets, free to rotate about fixed centers. (Fig. 2) In the 
absence of any disturbing force the two molecules will arrange themselves 
with their magnetic axes coincident with the line joining their centers. 
If an external field, H, be appUed which makes an angle with this 
line the two magnets will each be deflected through an angle ^, seeking 

i PhU. Mag. 46 (1873). p. 140. 48 (1874), p. 321. 

• Ewing, " Magnetic Induction in Iron and other Metala," p. 287. 



14 EARLY MAGNETIC THEORIES: QUIMBY 

a new position of equilibrium for which, evidently, 



2 m H r sin (^ - «) = m« CN/PQ», 

where m is the pole strength of the magnets, and 2r is their length. 

This position of the molecules corresponds to the initial stage of ihe 
magnetization in which there is a small increase in induced magnetism 
with increasing external field. 

When: 

the equilibrium becomes neutral and any further increase in H will 
result in instability. The magnets will then swing violently toward 
a new position of equilibrium with their axes nearly parallel to H. 
This sudden shift corresponds to the second stage in the nuignetisation 
in which a large increase in magnetic moment accompanies a small 
increase in the magnetizing field. 

Any further increase in H will not appreciably alter the positions of 
the molecules and we have the condition of approximate saturation. 

It remains only to note that if H is now decreased the magnets will 
not retrace the same path in returning to their original positions. The 
deflection accompanying a small decrease in H will be small until a 

^ second state of instability is reached, 

when they will swing back into posi- 
tions approximating the initial ones. 

A single pair of magnets of this sort 
would give a discontinuous hysteresis 
loop. If, however, we inuigine a large 
nmnber of such elements with their 
axes initially distributed at random it 
is evident that some of these will reach 
— -H the position of instability earlier than 

p 2 others, and the '^ magnetization curve" 

of the aggregate will be a smooth one. 
"Hysteresis loops" have been obtained experiment^y with a group 
of only twenty-four magnets, which are in perfect qualitative agree- 
ment with those observed for iron. 

The theoretical retentivity of a substance may be obtained by 
assiuning it to be composed of a large number of groups, with the mole- 
cules of each group arranged in some sort of symmetry. This is in 
agreement with the fact that iron and other magnetic metals are 
known to be composed of minute crystal matrices of the cubic system 
irregularly oriented throughout their mass. 



^ 



— H 



• * 

• / 
I* 




EARLY MAGNETIC THEORIES: QUIMBY 16 

It is characteristic of such a cubical formation that the permanent 
deflection of the molecules must necessarily be either 0^, 90^, or 180^. 
Referring to Fig. 2, it is clear that if ^ be the angle of permanent de- 
flection, we have three cases to consider: 

(1) Molecules for which 6 is less than 45^. These will su£Fer no 
permanent deflection. This is because the original lines are more 
favorably directed than lines at right angles to them. For these mole- 
cules (t> ^^ 6. 

(2) Molecules for which 6 is greater than 45^, and less than 135^. 
These wiU be permanently turned through one right angle. In this 
case * = d - 90^ 

(3) Molecules for which B is greater than 135^. For these molecules 
« ^ - 180^ 

If the axes of the molecules are initially directed at random, we have, 
as before, for the number of molecules whose axes lie between 6 and 
^ + d^, 

-smBde, 

and if the nuignetic moment of each molecule is fi, the contribution 
of these molecules to the net intensity of magnetization will be 

iin 
2 



flenoe the whole residual magnetism wiU be given by: 

1 = ^/ sin^cosdd + ^/ sin« ^ d 

4 



2 J iw 



+ ^ / sin ^ cos (^-180**) AS = 0.8927 /in. 
2 J iw 

4 

More recent researches seem to indicate that the behavior of the 
magnetic elements in crystals is not as simple as Swing's theory would 
lead us to believe. The theory is, however, a step in the right direction, 
for it attacks the problem which is fundamental in the explanation 
of ferromagnetism, namely, the evaluation of the mutual actions of 
the elementary magnetic units. 

In the preceding review we have not considered the various theories 
of magnetostriction which belong to the period under consideration. 
A discussion of these theories will be found in a later section of this reports 

i p. 225. 



16 PARA- AND DIAMAONBTISM: WILLS 



PROGRESS IN THE DEVELOPMENT OF THEORIES OP 
PARA- AND OF DIAMAGNETISM FROM 1900 TO 1920 

Bt a. P. Wills 
Professor of Mathematical Physics, Columbia University 

CONTENTS 

Introduction 16 

I The electric and the magnetic field due to a moving electron 19 

II The magneton 23 

III The distribution function in theories of paramagnetism 37 

IV Early attempts at electron theories of magnetism 48 

V The theory of Langevin 55 

VI Modifications of the theory of Langevin independent of quanta hypotheses 68 

VII Theories of paramagnetism based on quantum hypotheses 85 

VIII Diamagnetism in metals due to the motion of free electrons 103 

INTRODUCTION 

The development of theories of magnetism during the period which 
the present survey attempts to cover is characterized by successive 
efforts on the part of theorists to explain magnetic phenomena in terms 
of the properties of electrons in motion. 

Early in the period under review it was found that the assumption 
of motions of electrons in independent closed orbits in a material body 
was incompetent to produce a satisfactory explanation of magnetisation 
in the body. Some type of sub-molar structure of electrons was found 
to be needed. For convenience we shall designate such a structure a 
'^ magneton." The electron theories of magnetism to be reviewed are 
naturaUy differentiated through the more or less arbitrary structural 
properties assumed for the magneton. 

Any molecular theory of magnetism is, of course, essentially statistical 
in character and therefore continually faced with the weU known dif- 
ficulties of statistical mechanics. These difficulties assume rather 
formidable proportions in a theory which claims a generality sufficient 
to account for magnetic susceptibiUties observed at low temperatures. 
For it then appears that the theory has to part company with the law 
of equipartition of energy of classical mechanics and introduce in its 
place a law of distribution of energy among the magnetons of a body, 
depending upon some more or less plausible quantmn hypothesis. 

A primary object of all magnetic investigations on material bodies 
is, of coiurse, to find out as much as possible concerning the nature of 



PARA' AND DIAMAONETISM: WILLS 17 

the magneton. So far as we know it cannot be segregated and ex- 
amined; and our empirical knowledge of the magnetic properties^of 
a material body is of necessity derived from an experimental study 
of its magnetic quality in bulk. It is the bulk susceptibility which 
is experimentally determined. This is a statistical quantity, repre- 
senting the contributions of the statistical units, the magnetons, to 
the magnetisation of the body in bulk. In the consideration of 
any molecular theory of magnetism it is therefore necessary to bear 
in mind that the theory may weU stand the test of experiment, and yet 
the model of the magneton which it assumes be far from a true one, 
since different types of magnetons might have the same statistical 
properties. 

As far as fundamental physical ideas are concerned the reader of 
the following report wiU probably conclude that the interpretation 
and the extension of old conceptions, those of Ampere and of Weber, 
rather than the introduction of new ones, save those relating to quantmn 
theories, characterize in general the developments in molecular theories 
of para- and of diamagnetism during the years from 1900 to 1920. 

The development of electron theories of magnetism which began 
early in the period covered by the present report was stimulated in 
large measure by the theoretical writings of F^ofessor H. A. Lorenta 
and of Sir Joseph Larmor. Their results constitute a lai^e part of 
what is now termed classical electron theory with which the reader is 
supposed to have some acquaintance. 

Kinetic theories of magnetism are of necessity somewhat mathematical 
in character and the pages of the literature dealing with them are often 
encumbered with many rather formidable appearing formuke, which, 
while oftentimes necessary, operate as a deterrent to the average reader, 
who is more interested in the physical content of a theory than in the 
mathematical dress in which it is clothed. 

With the object of divesting, so far as possible, the various theories 
discussed below of the mathematical features which are shared by many 
of them in conunon the first three sections have been written. 
These sections are intended more for reference during the reading of 
the rest of the report than for continued perusal. The reader who so 
desires may therefore begin with Section IV, dealing with early attempts 
at electron theories of magnetism. 

For the purposes of the present review it has been found convenient 
to use a vector notation. That of Gibbs has been adopted. 

Vector quantities are printed in the heavy Bookman type — A, B, 
a, b . . and the corresponding scalar values in ordinary t3rpe — A, B,. 
a, b . . . 



18 PARA' AND DIAMAGNETISM: WILLS 

The reader who is unfamiliar with Vector Analyofl and who desires 
to follow those parts of the argument in the text in which vector methods 
are used will find ''Vector Analysis" by J. G. Coffin a very convenient 
book for reference. 

As regards units, for electric and magnetic quantities the Gaussian 
4system is used throughout. For other quantities c. g. s. absolute units 
are always used. To denote the velocity of light the letter c is used. 



"> 

t 



PARA' AND DIAMAGNETISM: WILLS 



19 



THE ELECTRIC AND THE MAGNETIC FIELD DUE TO A MOVING 

ELECTRON 

The explanations of magnetisation on the theories of magnetism 
which we shall notice later are referred back to the electric and magnetic* 
properties of free electrons in motion, or to the corresponding properties^ 
of some sort of rotating magneton. 

In the present section we shall therefore consider the electric and 
the magnetic field of a moving electron; and in Section II we shall 
consider the electric and magnetic properties of rotating magnetons, 
and also the mechanical moments to which they are subject when 

placed in an external electric or magnetic field. 

The electron, considered as a point charge, 

will at first be considered to be moving in any 

arbitrarily assigned manner. The electric and 

the magnetic force due to the moving electron 

may be calculated for any field point directly 

from its retarded scalar- and vector potentials.. 

Referring to Fig. 1, O represents the origin 

of a cartesian S3rstem of axes fixed in space; Q 

^ the position of the electron at the instant under 

consideration; s the position vector of Q with 

reference to O; P the field point; r the position 

vector of P with reference to O; and q a vector 

drawn from Q to P. 

The cartesian coordinates of Q and P are represented respectively 

by f , ri, f and x, y, z. From the figm^ : 




Fig. 1 



(1) 



= V (x - {)« + (y ^ r,y + (z - f).» 



If e be the charge on the electron and v its velocity, then by classical 
electron theory the scalar- and the vector potentials at the field point 
P are respectively expressed by: 



(2) *- 



K'-m_3 



A = 



ev 



h(-Tj')J 



.-9 

c 



where the quantities in square brackets are to be evaluated not at the 
time at which the electric and the magnetic forces are required but 
at a time previous by the interval required for radiation to travel 
from the point Q to the point P, that is at a time t — q/c. 

The potentials having been evaluated the electric and the magnetic 
force at the field point will be given respectively by: 



•20 PARA- AND DIAMAGNETISM: WILLS 

(3) E - - V * — ; H = curl A. 

e at 

Upon carrying out the operations here indicated the following ex- 
pressions for the electric and the magnetic force at the field point P 
are foimd: 

q* 

c*L q* \ cq/ cq* \ cq/ J 

The details of the calculation are somewhat involved and may be 
found in standard treatises dealing with electron theory, e. g., in The 
Theory of Electricity by G. H. Livens, p. 506. 

For the cases which will come under our consideration the velocity 
of the electron may be considered small in comparison with that of 
light, and the field point may be chosen so that its distance from the 
electron is small in comparison with the wave length of the radiation 
emitted by the electron. The general expressions for the scalar and 
the vector potential given by (2) then reduce to the ample ap- 
proximate expressions: 

e ev 

(6) * = - , A = - • 

q cq 

It may be noticed that here the potentials are not retarded. 

The corresponding expressions for the electric and the magnetic 
force due to a moving electron may be obtained directiy from (6) by 
taking the negative gradient of ^ and the curl of A. It is thus found 
that: 

<7) = = ^s « ' 

(8) H = — V X q. 

cq' 

These approximate equations might have been obtained, of course, 
from the general expressions (4) and (5) by introducing the restrictions 
above made. 

If the origin O be so chosen that s is small in comparison with r, 
the quantity 1/q in the expressions for the potentials may be developed 
in a series in which only the first three terms need be retained: 



\-i{^-f-im 



PARA- AND DIAMAGNETI8M: WILLS 21 

Inserting this expression for 1/q in (6) we find: 



(9) 



-^{(-^H.|(f)'}. 



Taking the negative gradient of ^ and the curl of A we now obtain 
the following expressions for the electric force and the magnetic force 
at the field point: 

(10) E . 1 {(l + ^■) (. - .),}. 

(.1) H-^.x{(l+i£^)(r-.)}. 

The mean value of H for an electron describing a circular orbit with 
constant speed will later be required. If H denote the mean value of 
H for this case, it is easily foimd from (11), upon observing that v 
= s, that: 



(12) 



H = - — :(3 s X s- -r — s xs J. 
2cr*\ r* / 



Thus, an electron describing a circular orbit with constant speed is, 
as far as its mean magnetic field is concerned, equivalent to a small 
magnet whose moment, t^, is given by: 

(13) V = - S X 8. 

This expression can be put in a somewhat simpler form as follows. 
Let <d be the angular velocity of the electron about the center of its 
orbit, then s = <dXs = a)nxs, ifnbe a unit normal to the plane of 
the orbit in the direction of u. We now have : 

sxs = a)sx(nx8) =a)S-sn= |Sn, 

where r is the orbital period, and S the orbital area. Then, from (13) : 

(14) »=^n. 

Cr 

The moment of the orbit wiU be subject to change if a magnetic field 
be created through it. Let H be the strength of the magnetic field at 
any instant and E the corresponding electric force. Supposing the 
area of the orbit, S, to be very small and its plane invariable. 



22 PARA- AND DIAMAQNETI8M: WILLS 



by making use of Stokes' theorem and Maxwell's field equation, curl 
E « — d H/c d t, we obtain: 

^ S S 

Upon integration the integral on the left gives 2x s E, and hence : 

2tsE » - — (n.HS); 

cdt 

the expression on the right representing the time rate of decrease of the 
magnetic flux through the orbit. If A (n-H S) denote the increment 
of this flux in the orbital time r, then: 

(15) 2 T s E = ^^ ' 

cr 

Again, since the moment of the force e E must equal the time rate 
of increase of the moment of momentum of the electron in its orbit, 
we have: 

„ d, ,. 2mcdfi 

seE= — (mB««)= — ; 

at eat 

consequently, if A /i denote the increment in fi in the orbital time, r: 

,-^v ^ 2 m c A/i 

(16) B e E = - . 

e T 

From (15) and (16) it follows that: 

e^ e' 

(17) A M = ; A (n.H S) = A (H S cos 6), 

where 6 is the angle between the directions of n and H. 

Mechanical Action upon a Moving fUectron in an External Electro- 
magnetic Field. 

If E and H now denote respectively the strength of the external 
electric and magnetic field, from fimdamental electron theory we have 
for the mechanical force, F, upon any electron: 

(18) F = eE + - V X H; 

c • 

and for the mechanical moment, N, of this force about the origin O, 

(19) N = es X (E X - V X H). 



PARA- AND DIAMAGNETISM: WILLS 23 

II 
THE MAGNETON 

Since, as mentioned above, the assumption of motions of free elec- 
trons in independent orbits is incompetent to lead to a satisfactory 
explanation of magnetisation, the concept of the magneton made an 
early appearance in modem theories of magnetism. 

The magneton is conceived to be a minute aggregate of positive and 
negative electrons, possessing certain arbitrarily assigned constitutional 
or structural properties. We first consider these properties. 

Fundamental Assumptions Concerning the Structural Properties of the 

Magneton. 

The algebraic sum of the charges of the electrons in a magneton are 
assumed to be zero. If the charge on a typical electron be e the struc- 
tural condition implied by this assumption is expressed by writing: 

(1) Se = 0. 

The distribution of the electrons in the magneton is supposed to 
be such that the electric moment of the magneton is zero. We now 
suppose that the typical electron of the magneton is the electron of 
Section I, and that the origin O coincides with the centroid of the 
magneton. Then (see Fig. 1, Sect. I) the condition that the electric 
moment of the magneton shall be zero is expressed by: 

(2) Ses « IDeJ + jSei? + kZef = 0, 

where i, j, k are imit vectors in the directions of the axes (x, y, z) respec- 
tively. 

It wiU appear presently that the electric and magnetic properties of 
the magneton depend in an important way upon the following quantities 
of the second degree in (, 17, T* 

(3) Pi = 2)6?, Pi^Dei?^, P8 = Sef«, 

(4) Di - Zeiyf, D, « Sff, D, = SJiy, 

(5) Qi = P2 + P», Q« = P» + Pi, Qs = Pi + Pi. 

From the analogy of these quantities with corresponding quantities 
in mechanics it is appropriate to call the Q's and D's respectively 
Moments of Inertia of Charge and Products of Inertia of Charge. 

The Electric Potential and the Magnetic Potential for a Rotating 

Magneton. 

In the applications of the present theory with which we shall be 
concerned in our review of theories of magnetism the velocity of any 
electron will be small in comparison with that of light, and the distance 



24 PARA-' AND DIAMAQNETI8M: WILLS 

of the field point from the magneton will be small in comparison with the 
wave length of the radiation emitted by it and yet large in comparison 
with the dimensions of the magneton. 

The appropriate equations for the potentials will therefore be fur- 
nished by the equations (9), Sect. I, (for the potentials of a sin^ electron) 
through summation over aU the electrons in the magneton, the origin O 
being supposed at the center of the magneton. We thus obtain for 
the electric and the magnetic potential of the magneton respectively: 

^ «e / r.s . 3/r.sVl 

c r I i« 2\ r« / J 

where v is the velocity of an electron, s and r the position vectors of 
the typical electron and the field point, respectively. 

Taking account of the structural conditions given by (1) and (2) 
these expressions reduce to: 

^ ^ ^ 1«« /r-8 . 3/r.sVl. 

In general, the approximation will be suflScient if only the first term 
in the expression for A be retained; then: 

(8) A = - 2 e V — . 

The right hand member of this equation may be transformed as 
follows — noting that v » s we have identically: 

^{vr.8-8r.v + |(88.r)|-^rx(7X.)+ii(88.r); 
and, therefore: 

where 

(10) V- — 2esxv. 

The Mean Value of the Vector Potential for a Rotating Rigid 

Magneton. 

For a rigid rotating magneton the mean value during one revolution 
of the second term on the right of (9) will vanish, and if we denote the 
mean value of A by X and of t^ by ^, then: 

(11) A - i^ 



▼ r.s ^ 
2 



PARA- AND DIAMAONETISM: WILLS 25 

Ftom the form of this expression for the mean vector potential it 
appears that the mean field of a rotating magneton is the same as the 
field of a small magnet with a moment t^; and it may be easily seen that 
the direction of the vector ^ will coincide with that of the axis of rotation 
of the magneton. 

If a, /3, 7 be the direction cosines of the axis of rotation, and therefore 
of tf , the scalar components of the mean vector potential of the magneton 
will be given by: 

Ai = - OSz - 7y), 
(12) A, - ^, (7X - OS), 



Ai - - (ay - /3x). 
r* 



The Mean Value of the Magnetic Force Due to a Rotating Rigid 

Magneton. 

Taking the curl of A ¥^ find for the mean value, H, of the magnetic 
force: 

(13) H-^,5 rr-^»; 

and the scalar components of this force are easQy seen to be given by : 

Hi = 3-rax + ftr + 7z)x-^' 
r' r* 

(14) Hi»3-,(ax + ftr + Tz)y-^' 

r r^ 

H, = 3-.(ax + ftr + 7z)z-3• 
r* r* 

It appears from these equations that the mean magnetic field is 
symmetrical to the axis of rotation of the magneton; that the lines 
of force Ue in planes through the axis of rotation; and that the mean 
field is equivalent to the field of a magnetic doublet whose axis is parallel 
to the axis of rotation and whose moment is equal to «f. 

This equivalence, of course, hol(is only for the mean value of the 
magnetic field of the magneton, and not for the instantaneous value. 
For the latter the second term on the right of (9) comes into considera- 
tion; and accordingly the instantaneous value of the field will vary 
with the time, giving rise to radiation, with which, however, we are not 
B specially concerned. 



26 PARA- AND DIAMAGNET18M: WILLS 

The Magnetic Moment of a Rotating Rigid Magneton 

As has been seen above the mean value of the quantity t^ represents 
the mean time value of the moment of a rigid rotating magneton; it 
will therefore be convenient to refer to the quantity t^ itself as the 
moment of the magneton. 

When the magneton is rigid, v = u x s, and we have from (10) : 

I^=~2)e8x(«x8) 

(16) «--2e(B»« - tt-ss) 

2c 



iM 



(? + 1|^ + f*) « - («1 f + «|1| + «8f) 8. 



where (, fi, f are, as usual, the scalar components of s, and ah, «i, wi 
are the scalar components of u, the angular velocity of the magneton. 
From the last of these equations it follows, with the aid of (3), (4) 
and (5), that: 



^-i{ 



(Qi«i - D,w, - I>,»,)i 

(16) +(- D,«i + Qiw, - D,«,)j 

+(- DiG)! - Di«, + Qi«i)kV 

From this equation it appears that t^ is a self-conjugate linear vector 
function of u. In fact, the relation between v ftnd u is precisely analo- 
gous to that of the moment of momentiun of a rigid body to its angular 
velocity of rotation, the Q's in the present case corresponding to the 
moments of inertia about the axes and the D's to the so-called products 
of inertia. 

The Torque upon a Magneton due to an External Electromagnetic Field. 

We now suppose the magneton to be placed in an electromagnetic 
field which may vary in space and in time. The electric force and the 
magnetic force of this field will be denoted respectively by E and H. 
The torque, N, acting upon the magneton due to the action of this 
field has now to be found. 

With reference to the origin O, this torque, from (19) Sect. I, will 
be given by: 

(17) N = Se8x(E-f-vxH), 

c 

where the summation is over all the electrons in the magneton. 



PARA' AND DIAMAONETISM: WILLS 27 

Since E and H may be assumed continuous, they may respectively 
be developed into the series: 

<18) E = E^+(8.VE)o + , 

<19) H = H,+ (s.VH)^ + , 

where the subscripts indicate that the quantities to which they refer 
are to be evaluated at the point O. 

If N' and N'" denote respectively the turning moments upon the 
magneton due to the external electric and magnetic force, then: 

<20) N « N* + N." 

In the evaluation of N^ attention must be paid to (2), expressing that 
the total electric polarization of the magneton vanishes. On this 
accoimt the first term on the right of (18) contributes nothing to the 
value of N.^ If furthermore we restrict ourselves to terms of the 
second order of smallness in the small quantity s, only the second term 
in the development of E need be considered and the evaluation of N* 
then gives: 

(21) ir = Se8xsVE, 

where it is to be imderstood that the derivations in the factor s . VE are 
to be effected at the point although the zero subscript is not explicitly 
carried forward. 

In a similar manner the evaluation of N"" to the same order of approxi- 
mation gives: 

(22) N" = 52esx(vxH), 

where H is to be taken as the external magnetic force at O. 

If the triple vector product in the sum on the right of (22) be expanded 
and accoimt taken of the perpendicularity of s and ▼, it may be seen 
that (22) transforms into: 

N" = ZesHv; 

or, in case the magneton is considered as rigid : 

(23) N" = ^«xc, 

where u is the angular velocity of the magneton about an axis through O 
and: 

(24) c^ZesHs. 

The scalar components of the vector c with the aid of (3) and (4), 
remembering that (, 17, f are the scalar components of s, may be ex- 
pressed as follows: 



28 PARA' AND DIAMA0NETI8M: WILLS 

Ci = PiHi + DA + DtHi, 

(25) C = DA + PiH, + D,H„ 

C, « DtHi + DiH, + P,H,, 

showiBg that c is a self-conjugate linear vector function of H. 

Making use of (3) and (4) tiie scalar components of IT given by (25) 
may be expressed by: 

Ni* = D,— - + ?,— -• + Di— ' - Di^ - Di^ - P,~' 
dx dy dz dx dy dz 

(26) N,' = Di^ + Di^ + Tt-f^ - Pi—' - D,— • - Di-— '' 

dx dy dz dx dy dz 

N, - Px- + D.- + Di-^ - D.— - P.- - D.- 

Ftom (23) with the aid of (25) the corresponding expressions for the 
scalar components of the turning moment upon the magneton due to 
the external magnetic field are seen to be given by: 

Ni~ = -V«,(D,Hx + DiH, + P,H,) ~ «,(D,H, + P,H,+DiH.)l, 



(27) 



N," = ^|«,(PiHi + DA + DiH.) - ch(D^i + DiH, + P,H,)l, 
N." = ^|«i(D A + P«H, + DiH.) - a),(PiHi + DA + DiH,)|- 



Equations for a Rotating Rigid Magneton Referring to its Principal 

Axes of Charge. 

It is always possible to choose three mutually perpendicular axes 
through the centroid of a magneton such that for them the products of 
inertia of charge vanish: 

Di = Di « Di « 0. 

These axes are called Principal Axes of Charge. 

The equations foimd above for the magnetic moment of a rigid mag- 
neton and for the scalar components of the torques upon it due to the 
action of an external electric and an external magnetic field assume much 
simpler forms when the axes of reference are Principal Axes of Charge. 

Thus^ from (16), we have for the magnetic moment of a magneton: 

(28) II = - (Qioni + Qm j + Q««*) ; 

zc 



PARA' AND DIAMAGNBTISM: WILLS 29- 

and, from (26) and (27), for the scalar components of the torques: 

(29) N,- = P.f^ - P.'^'. 

due to an external electric field E; and : 

Ni" = - (P«H*»« - P,H*«,), 
c 

(30) N," = -(P,Hx«, - P,H,«0, 

c 



N,» = -(PiHiWi - PiH,«*). 
c 



due to an external magnetic field H. 

Equations for Rotating Spherical and Axial Magnetons Referring to 

Principal Axes. 

For the purpose of the present review it is only necessary to consider 
two special types of magneton, known respectively as the Spherical 
Magneton and the Axial Magneton. 

The Spherical Magneton is defined as rigid and one for which the 
principal axes of charge and of inertia coincide and for which the prin- 
cipal moments of inertia of charge Qi, Qs, Qs and the principal moments 
of inertia, A, B, C, are respectively equal: 

(31) Qi = Q, = Q, = Q .-. p, = p, = p,; 

A =B =C =J. 

The Axial Magneton is defined as rigid and one for which the prin- 
cipal axes of charge and of inertia coincide and for which the principal 
moments of inertia of charge and the principal moments of inertia are 
respectively equal for two of its principal axes, say 1 and 2: 

m^ Ox = Q. = Q, ••• Px = P,; 

<32) A = B = J. 

For the magnetic moment we have, from (28) : 
(33) » = - « 

for the Spherical Magneton; and: 



30 PARA' AND DIAMA0NBT18M: WILLS 

<34) t^ - ^(Q«ii + Qwij + Q,»»k) 

for the Axial Magneton. 
For the torque due to an external electric field E we have, from (29) : 

^* 2U a,; 

*T. Q/5E, dE,\ „ Q ,« 
<^> N.--|(---)..Mr-^curiE; 

^''2\dx dy) 
«nd, from (30), for the torque due to an external magnetic field: 

Ni" = |(«*,H, - «A), 
<36) N," = ^(«A - «,H,), .% N- - J« X H, 

N,- = |(«iH,-«,Hi); 

or a Spherical Magneton. 

From (29) and (30) the corresponding expressions for an Axial Mag- 
neton will be given by: 

<»7, W - P. f - Sf • 

«.-f(f-f)-f<-«.. 
for the torque due to an external electric field E; and: 

N.- - ?(PA-. - fa^) 

N,- - ^(E^ - H,«,) - ^(« X H),, 

ZC iSC 

lor the torque due to an external magnetic field H. 



\ 



PARA' AND DIAMAONETISM: WILLS 31 

The Rotary Motion of a Rigid Magneton Subject to an External Elec- 
tromagnetic Field. 

We assume the reference axes to coincide at the instant xmder con*^ 
cdderation with the principal axes of inertia of the magneton, for which 
the moments of inertia are A, B, and C ; and also that the principal axes, 
of charge coincide with those of inertia. 

By Eukr's dynamical equations of motion : 

Acii - (B - C)«j«, = Ni' + Nr, 

(39) Bci, - (C - A)«,«i = W + N,", 

Cci, - (A - B)«i«i = Ni' + Ni", 

where the N* and N"' torque components in the general case are given 
by (29) and (30). 

Ftom these equations the rotary motion of the magneton may be 
theoretically determined when no dissipative forces are assumed. 

Special Case of the Spherical Magneton. 

In this case we have A = B=:C«J and, upon introducing the 
expressions for the torque components given by (35) and (36), in the 
equations of motion (39) it appears at once that they are equivalent to 
the single vector equation: 

(40) Jii « %curl E + Kx H); 

2 c 

Since, by virtue of one of Maxwell's field equations, curl E "^ 
— dH/cdt, this equation may be written: 

^^'^ -^dt^-^U"""^} 

This equation assumes a simpler form if the time derivations are 
taken with respect to the moving space of the magneton instead of 

fixed space. If 37 denote time derivation with respect to the former^ 

at 

then: 

d tt dtt d H dH ^ 

and equation (41) may therefore be written: 

d « Q d'H 

(43) J^-^ = - -5L )L^ 

^^ dt 2c dt 

Integration of this equation gives: 



32 PARA' AND DIAMAGNETISM: WILLS 

where u, denotes the value of <d before the application of the external 
field. 

From the last equation it appears that the establishment of an external 
electromagnetic field brings into existence a rotation of the magneton 
about an axis parallel to the lines of force of the external field of amount 

will depend upon whether Q is negative or positive. 

The magnetic moment of a spherical magneton is given by (33), 
from which with the aid of (44) : 

Qi 
(45) ,^ « 1^^ - 4^^* 

Therefore the effect of the establishment of the external field upon the 
moment of the magneton is to bring into existence a component 
— Q'H/4c'J directed parallel to the lines of force of the external mag- 
netic field; since J is a positive quantity the coeflident of H in (45) will 
be negative. 

In the particular case where the external magnetic field remains con- 
stant in time the equation of motion (41) for a spherical magneton 
reduces to: 

<46) J« - ^« X H. 

In accordance with this equation, since u x H is a vector which is 
perpendicular to w, the magnitude of !■» will remain invariable; but, 
except in the special case where » is parallel to H, the direction of the 
axis of rotation will continually change both in fixed space and in the 
magneton. The component of <d in the direction of H will not change 
but the component perpendicular to H will rotate about the direction 
of H with the constant angular velocity 

(47) "• - - ^- 

The vector u itself will rotate about an axis parallel to H with this 
same angular velocity; and the magneton will perform a reg^ular pre- 
cession about this axis. From (44) and (47) : 

(48) « = «o + «!• 

The angular velocity w of the magneton may thus be regarded as the 
sum of two components; cjo, representing its angular velocity before the 
application of the external field, and ui, representing an induced angular 
velocity about the direction of the lines of force, due to the creation of 
the external field. 



PARA' AND DIAMAONETISM: WILLS 33 

The precessional motion of the magneton takes place in a manner 
similar to that of a synmietrical top in a gravitational field, but with the 
di£Eerenoe that the applied torque in the present case, QuxH/2c, is 
proportional to the angular velocity, while in the case of the top it is 
independent of the velocity; thus it comes about that the precessional 
velocity, in the case of the magneton is independent of its angular 
velocity, while in the csuse of the top it is inversely proportional to the 
angular velocity. 

Since, by virtue of one of Maxwell's field equations, curl E == f or 
a magnetic field of constant strength, it follows from (35), (36) and 
(38) that the torque on a spherical magneton in a constant external 
magnetic field is t^ x H or, on accoimt of (45) : 

(49) »o X H. 

The magneton is thus subject to a couple equal to that which would 
be experienced by a magnetic needle of moment yo placed in the same 
magnetic field H. But the motion of the needle would be quite different 
from that of the magneton, in that the needle would move in a plane 
containing its axis and parallel to the lines of force, while the magneton, 
due to its gyroscopic properties, performs a precessional motion about 
the direction of the lines of force. If either the needle or magneton is 
to assume a position with axis along the lines of force it is necessary 
in general that dissipative forces come into play. 

Special Case of the Axial Magneton. 

For the axial magneton A — B — J and the general equations of 
rotary motion (39), with the aid of (32) reduce to: 

J^ - (J-Oo^, = ^ ^' - P.'^ + -f P,«.H. - %M,) ' 

2 dy dz c\ 2 / 

(50) Jci, - (C- J)«^ = ?»?*-% V-* + Y%H» - P»"iH»V 

dz 2 dx c\2 / 

«■ - Kf - f ) + *'-«• - "-«■'• 

The third of these equations refers to rotation about the axis of the 
magneton and may be put in the form: 

(51) Ci, = |*|(curl E), + ^(« X H),V 
By virtue of one of Maxwell's field equations: 

(curlE), = ---jr; 

c at 



34 PARA' AND DIAMAGNETISM: WILLS 

BO that (61) may be written: 

da)s 



Qs /dH \ ; 

2cCV dt /, 



dt 

or, if the derivations be taken with respect to the moving space of the 
magneton, 

d 0)3 Qs d Hs 

"dt "" " 2cC^ 

Integration of this equation gives: 

(52) Wj = 0)03 - 2^^»' 

where €003 represents the angular velocity of the magneton about its 
axis before the application of the external field. The external field 
thus produces a change in the angular velocity about its axis of amoimt 
— Q3Ha/2cC. It wiU also produce changes in the velocities of rotations 
about two perpendicular equatorial axes the equations of which are 
the first two of equations (50), assuming no dissipative forces. Owing to 
radiation due to the disynmietry of structure of the magneton with 
respect to these axes the motions about them would in course of time 
be damped out leaving only the motion about its axis. 

To the latter there corresponds a magnetic moment which, from 
(34) and (52), will have for its scalar value: 

(53) M = Mo3 - ^^^^^ 

where 

(54) tu>z = ^"03; 

Aioa is the scalar value of the axial component of the moment of the 
magneton before the application of the external field. 

Energy of a Rotating Axial Magneton in a Constant External 

Magnetic Field. 

In what folbws the axial magneton will be supposed to consist of 
a rigid system of negative electrons symmetrically spaced about their 
centroid and rotating about it, the corresponding positive charge being 
in the form of a nucleus at their centroid or of a concentric sphere. 
In this case we may write in equation (34) for the magnetic moment of 
the magneton: 

Q = eJ/m and Qs = eC/m. 

For the total energy, U, we may write: 

U = Ui + U, + U,, 



PARA' AND DIAMAQNETISM: WILLS 



35 



where Ui lepiesents the energy due to the translatory motion of the 
magneton, Ui its energy of rotation and Us the mutual energy of the 
magneton and the external field, which, according to the point of view, 
may be regarded either as kinetic or potential. 

If M denote the mass of the magneton and x, y, z the coordinates of 
its centroid we have for its translatory energy: 



(55) 



Ui = y (i« + ^ + 2«) 



In the calculation of the rotatory energy of the magneton we suppose 
((y i7y r) to be axes coinciding with its principal axes and therefore fixed 
in the magneton, A, B, C being its moments of inertia about the axes 
of (, 17, i respectively; since the magneton is now supposed axial, we put 
A = B = J. 
To specify the position of the magneton with reference to the external 

field and fixed space we use Eulerian 
angles 0, ^, 0. 

Referring to Fig. 2, is the angle 
between the positive directions of 
the external field H and the axis f; 
^ is the longitude of the line of 
nodes, on defined as a line per- 
pendicular to the plane determined 
by the directions of the field H and 
the f-axis; and is the angle be- 
tween the line of nodes and the 
f-axis. 
If 0)1, 0^, 0)1 be the scalar compo- 




r 



Fig. 2 



nents of the angular velocities of the magneton about the axes (, 17, f , 
respectively, then: 

coi — ^sin0sin0+0oos0, 
.(56) ctf|sj^sin0cos0 — dsin0, 

0)3 = ^ cos + 0. 

We shall therefore have for the energy of rotation of the magneton: 



(57) 



u, = ^(^ + i^ sin« ^) + ^(0 + ^ cos ey. 



Considering the mutual energy Us of the magneton and the external 
field as kinetic we may write^- 



(58) 



U.-i»H. 



1 Cf. R. GaoB, iifm. d, Phyt. 49, p. 164; 1916. 



36 PARA" AND DIAMAONETISM: WILLS 

where i^ is the xnagDetic moment of the magneton. Upon noting that 
Q ^ eJ/m and Qs » eC/m where m is the majBS of a constitutive 
electron of the magneton, it follows from (34) that: 

(59) V = ^ (''"I* + J«ij + C«»k). 

Zmc 

Upon taking the scalar product of H with this expression for i^, sub- 
stituting the expressions for 0)1, (at and <ai given by (56) and inserting 
the resulting expression in (58) we obtain: 

(60) Us = * v-H = :^H{J^ sin* ^ + C(0 + ^ cos d) cos $]. 

4mc 

Finally, upon adding the expressions for Ui, Us and Us given by (55), 
(57) and (60), we obtain for the total energy of the axial magneton in a 
constant magnetic field: 

M 

(61) U = -(x' + y' + i*) 

+ ^(^ + ^ sirf e) + ^(0 + ^ cos $y 



+ ' 



-^h/j^ sin* ^ + C(0 + ^ cos d) cos e\. 
4mc ( j 



In the writing of the present section the treatment of the subject of 
the magneton as presented in Abraham's "Theorie der Elektrizitat" 
has been of much assistance. 



PARA- AND DIAMAONETISM: WILLS 37 

III 
THE DISTRIBUTION FUNCTION IN THEORIES OF PARAMAGNETISM 

In kinetic theories of magnetism the problem of the determination 
of the distribution of the axes of the constitutive magnetons of a body 
placed in an external magnetic field arises. A knowledge of this distri- 
bution is necessary before the contribution of the magnetons to the 
resultant magnetic moment due to the action of the external magnetic 
field upon the magnetons can be calculated. For convenience of 
reference later some results of statistical theory will be considered in 
the present section. 

Let us consider a S3rstem, subject to no external field of force, con- 
sisting of a large number of like statistical imits, the t3rpical one of which 
is specified as regards its configuration by the generalized coordinates 

qi qr, subject also to the condition that the total energy of the S3r8- 

tem is constant. Let the n generalized momenta of the system be 
denoted by pi p^. 

We suppose the generalized coordinates and the momenta to be 
subject to statistical variation, through thermal agitation for instance. 
Then if N be the niunber of units per unit mass, in accordance with 
statistical theory, when the system is in a state of equilibriiun the 
probable niunber of units per unit mass, say dN, which have values of 
their coordinates and momenta lying respectively within the specified 
limits 

qi and qi -h dqi q„ and q„ + dq„, 

Pi and Pi + dp, p„ and p„ + dp^, 

wiU be expressed by the law of distribution: 

(1) dN = ae'^dOf, 

where 

dl2 := dqi. . . .dq^dpi. . . .dpo, 

c is the total energy of a unit which is subject to statistical variation 
expressed in terms of the q's and p's and a and h are constants. 
For the determination of the constant a we have the condition: 



(2) 



fae'^'dif = N, 



where the integration is to be extended over all possible values of the 
variables whose differentials appear in the expression for dQ\ 
The fimction 

oe-^"^- 

is called the distribution function for the system of units. 

In some cases it may be convenient to introduce new variables in 
place of some of the generalized momenta. Thus, let us suppose m 



38 



PARA' AND DIAMAQNETI8M: WILLS 



of the generalised momenta, say pi pm, to be expressed in terms of m 

new variables, say ri rm, through the equations: 

Pi • fi(ri. . . .r^, 



fai(ri. . . .r^). 



By differentiation: 
dpi 



dp 



9p\ 



■dri+ +Z~*'' 

ori dr. 



m) 



«P-+....+?Psdr.. 



dp. 



dr, 



dr. 



From a theorem due to Jaoobi: 

dpi. . . .dp„ ■• Adri. . . .dr„, 

where A, the modulus of substitution, is given by the determinsntal 
expression: 

(3) A- 



dpi 
dr, • • • • 


dpi 




«P- 
dr. ••• 


dP- 
• •dr- 



K we write: 

do — dqi. . .dqndri. . . .drndpoH-i dpn, 

then: 

(4) do" - 6dSL 

The law of distribution (1) is therefore equivalent to: 

(5) dN « ae-**AdO, 

where the energy c is now supposed expressed in terms of qi . . 
Ti- . . .r^^ and Pn£fi p^. 



q-> 



Case of a System of Axial Magnetons in a Constant External Magnetic 

Field. 

It will be assumed for the present that the density of distribution of 
the magnetons is so small that the molecular field at any given magneton 
due to the others is neglible. It will also be assumed that the accelerar 
tions of the magnetons are so small that their loss of energy by radiation 
may be neglected. Furthermore the restrictions, whereby Q=eJ/m 



PARA- AND DIAMAGNETISM: WILLS 39 

and Qs^eC/m, imposed upoD the axial magneton in the last part of 
the preceding section will be supposed to hold. 

The total energy of the system may then be considered as constant, 
since the constant external magnetic field can do no work upon the 
magnetons, the corresponding mechanical force upon the constitutive 
electrons of the magnetons being perpendicular to their directions of 
motion. 

We may now take for the total energy of the t3rpical magneton of 
the system the expression (61) Sect. II: 

(6) u = ^(i« + ^ + i«) + ^(^ + ^ sin« ^) + ?(^ + ^ cos ey 



+"• 



|j ^ sin«^ + C(0 + ^ cos e) cos sX' 



4mc( 

where x, y, z are the coordinates of its centroid and $, ^, ita Eulerian 
coordinates. 

From this expression, since the total energy is kinetic, by partial 
differentiation we obtain for the corresponding generalized momenta, 
say u, y, w, p, q, r, the following expressions: 

u = Mx, V = My, w = Mz, p — Jd, 



. • 



eH 

(7) q « J^ sin« ^ + C(«+^ cos $) cos $+-- — (J sin* B+C cos» 6), 

4mc 

eH 

r = C(0 + ^ cos d) + ' — C cos e. 

4mc 

The statistical variables of the system are now x, y, z, u, v, w, 0, 
^1 01 Pf Qi c^<l ^' But it will prove convenient to replace the momenta 
P> <h f by new variables P, Q, R, using the following equations of sub- 
stitution : 

p = PcoB0 — Qsin0, 

eH 

(8) q- (Psin0 + QcoB0)sin^ + Rcos^+7— ( J sin* ^ + Cco^d), 

4mc 

r = R + -:^HCco8d; 
4mc 

from which by (3) we find for the modulus of transformation: 



(9) 



cos ^, — sin 0, o 

sin sin 0, sin cos 0, cos ^ 

o . o . 1 



= sin ^ 



40 PARA' AND DIAMAGNETI8M: WILLS 

From (6), with the aid of (7) and (8) : 

(10) u-2li(u* + V + W) + ^ + | 

eH 
+ z — (Pain^8in^ + QcoB08in^ + RcoBd). 
4nic 

We are now dealing with a system of statistical units, the magnetons, 
which is subject to an external field of magnetic force, and the question 
arises as to the form of the function t appropriate to this case. Gans, 
in the paper cited above, has shown this to be equal to this expression 
for U modified through multiplication of the last term by the factor 
u; so that: 

1 P'-l-O' R* 

(11) -^("*+-*+-*)+^+ic 

eH 

+ „p (P sin ^ sin ^ + Q cos sin ^ + R cos ^). 

In this expression the coordinates x, y, z, ^ do not appear explicitly. 
Therefore the law of distribution for the remaining statistical variables 
will be independent of these coordinates. Furthermore the expression 
involves the statistical variables u, v, w only as a sum of squares and 
therefore, as a well known result of statistical theory, the law of dis- 
tribution for the remaining variables will be independent of u, v and w; 
moreover the constant h in the law of distribution will have the value 
given by: 

2kT 

where T denotes the absolute temperature and k the gas constant for 
a single molecule, known as Boltsmann's constant. 

Now from the point of view of magnetic theory we shall be concerned 
only with the law of distribution of the statistical variables B, 0, P, Q, R; 
and the appropriate expression for t for this case is obtained from (11) 
by simply ignoring the terms involving u, v and w. 

If then dN now denote the number of magnetons per unit mass whose 
statistical variables. By 0, P, Q, R, have values which lie within the 
element of phase dQ given by: 

dQ » d0d0dPdQdR, 

the equilibrimn law of distribution for these variables will be expressed 
by: 

(12) dN-oe'^sin^dO, 



PARA- AND DiAMAGNBTISM: WILLS 41 

where 

(13) €« ^^;J^+ -^ + ;^H(Pan08ind+^ 

2J 2L/ 2mc 

We shall have occasion to consider another case in which the number 
of statistical variables involved is still further reduced. In this case 
the angular velocity <at of any magneton about its axis of symmetry is 
considered constant and the same for all magnetons. This requires 
that the quantity R shall be constant, since: 

(14) R = C(^ + ^ cos d) = C«s. 

Consequently R may no longer be considered as a statistical variable 
and the statistical variables of the present case are therefore $, 0, P, Q. 
The appropriate expression for the energy function for this case is now 
required. 
From (52) Sect. II, noting that Qs/C » e/m and that Ht » H cos tf : 

«» = Was - ^H cos e. 

Since R — Ccoa, we have, with the aid of this expression, for the sum of 
the terms in (13) involving R: 

(15) S,+ R;r-H cos ^ = iC«o,« - mH cos d, 

2C 2mc 

where 

2mc 

fi denotes the constant scalar value of that portion of the magnetic 
moment of the magneton which is due to its rotation about its axis of 
symmetry. 

The appropriate expression for the energy function in the present case 
may now be obtained directly from (11) through elimination of R by 
means of (15), thus: 

(17) U = JL(u.+v«+w^) + ^±^ + ^^' 

2M^ ^ 2 ^ 2 

eH 
H (P sin ^ sin ^+Q cos ^ sin ^)— JmH cos $. 

4mc 

The modulus of transformation is easily seen to be sin as before. 
If now dN denote the number of magnetons per unit mass whose statis- 
tical variables, 6, 0, P,Q have values which lie within the element of phase 
do given by: 

(18) dQ = de d0 dP dQ, 

the equilibrium law of distribution for these variables will be : 

(19) dN - oe""" an tf do, 



42 PARA' AND DIAMAONETISM: WILLS 

where 

pi J. Q2 Q 

(20) € = ^^ +-— H(P8in0 8m^ + QcoB^8in^) -mHcob^ 

2J 2mc 

the teims involving u, v, w being ignored as before, and likewise the con- 
stant term Cctf'os/2. 

The constant a in formulas (12) and (19), if lequiied, may be deter- 
mined in each case from the condition: 

(21) Joe'^'sinddQ^N. 

where the integration in each case is extended over all values of the 
variables whose differentials appear in the corresponding expression, 
for dfi. 

The Langevin Distribution Formula. 

In the theory of Langevin the magnitude of the magnetic moment of 
a molecule (magneton) is supposed constant and directed along a polar 
axis, contributions to its magnetic moment due to its rotations about 
its equatorial axes being ignored. In effect, the Langevin magneton 
may therefore be considered as an axial magneton whose rotation about 
its axis is not subject to statistical variation, and for which the dynamical 
and magnetic effects due to rotations about its equatorial axes may be 
taken as negligibly small; the latter condition requires that: P » Q » 0. 

The law of distribution in Langevin's theory of a paramagnetic gas 
is simply obtained from (19) by placing P =" Q » in the expression 
(20), which involves the disappearance of the coordinate and deleting 
d0, dP, dQ in expression (18) for dQ. 

The Langevin law of distribution is thus found to be : 

(22) dN = oe '**' sin ^ dd, where a ^• 

In accordance with this formula the paramagnetism of a body con- 
stituted of Langevin molecules depends simply upon the distribution 
of the axes of the magnetons with respect to the external field; it is 
subject, of course, to the restriction of the general theory so far developed 
that the effects of molecular fields are ignored. This restriction is 
unimportant in the case of a paramagnetic gas. 

For calculation of the magnetisation in Lange vin^s t heory of a para- 
magnetic gas the spatial mean value of cos $, say cos 0, will be required. 
From (22) it is easily found that: 

(23) cos^ = coth a 

a 



PARA- AND DIAMAONETISM: WILLS 43 

Modification of Langevin's Distribution Formula Introducing the 

Magnetic Molecular Field. 

A modification of Langevin's distribution formula for a paramagnetic 
gas, depending upon the consideration of the molecular field due to 
the magnetons of which the body is supposed constituted, will next be 
considered. 

In specifying the magnetic field at the centroid of a magneton in an 
isotropic body we may proceed as follows. 

Imagine a small sphere of radius s drawn about the centroid, s being 
the shortest distance between the centroid of the magneton in question 
and that of its nearest neighbor. Concentric with this sphere imagine 
a second sphere drawn with radius s' large in comparison with s but small 
in comparison with the bulk dimensions of the body. 

The magnetic force at the centroid of the t3rpical magneton is then 
the vector sum of the external force H, the force contributed by the part 
of the body outside of the s' sphere, which is well known to be 4irI/3 
where I is the intensity of magnetisation, and a force. A, due to the 
magnetons contained in the zone between the spheres of radii s and s' 
respectively. 

It is with the determination of the field A, called the molecular field, 
that we are now concerned. 

If F denote the resultant field, then: 

(24) F-H + -^I + A 



K + A, (K = H + ^ I). 



Now it is evident that, as we pass from magneton to magneton in the 
vicinity of the t3rpical one under consideration, A will vary in direction 
and magnitude. 

Let N be the number of magnetons per unit mass at a point P in a 
paramagnetic body supposed constituted of axial magnetons for which 
it may be assumed that P and Q are negligible. 

In accordance with the fundamental assumption, which closer exam- 
ination shows to be justified, that all directions of the molecular field 
A are equally probable, for a magneton selected at random that part, 
say dN|t, of the total number N per unit mass which find themselves 
in a molecular field A whose direction is delimited by a small cone with 
vertex at P and of solid angle do) and for which the magnitude of A 
lies between the limits A and A + dA, will be expressed by: 

dN. = N ^ w(A)dA, 



44 



PARA' AND DIAMAGNETISM: WILLS 



where w(A) is a probability function to be specified later. These 
magnetons are designated as Group A. 
Referring to Fig. 3 we may express dta by: 

dia ^ sin y d^ d^, 

where 7 and are the co-latitude and the longitude of du with respect 
to a polar axis in the direction of K; also from the figure: 

(25) A« = P + K* - 2FK cos 5, 

(26) P = A« + K* + 2AK cos 7 

where 6 is the angle between K and F. 




Fro. 3 



By differentiation of (26) we find for all magnetons of Group A (for 
which A is constant) : 

FdF 
sm 7 07 « — 



AK 



We mivy therefore write: 



(27) 



dNa-- -^"J^FdAdFd^. 
4tK a 



Let B be the angle which the axis of a typical magneton of Group A 
makes with the direction of the field K; then a number, say dNb, of 
the magnetons of Group A will make angles with the direction of K 
which lie within the limits $ and B + 60. These magnetons are desig- 
nated as of group B. The number dNb will obviously depend upon the 
law of distribution of the axes of the magneton in Group A and we 
may write appropriately: 

dNb = dN«f(^)d^, 
where f(B) is a function to be determined. 



PARA' AND DIAMAONETISM: WILLS 45 

It is evident that the number of magnetons of Group A which make 
angles with the direction of K and which lie within the Umits $ and 
$ + d$ will be equal to the number of the same group making angles 
with the direction of the resultant field F which lie within the limits 
p and p + dfi, is p designate the angle made with F by the axis of a 
t3rpical magneton of Group A. The latter number is given by the 
Langevin law of distribution. Consequently: 

{{6)6$ = oe •«*'^ sin p dfl, where a = ^' 
and therefore: 

dN b = dN« a e • ** '^ sin /9 d/9 ; 

or, upon substitution of the expression for dNa given above, 

(28) dNb= - ,-^,^Fae'"''^8mj8dAdFd/Jd*. 

4tK a 



From the condition: 



r 

/ 



ae sm/9dj3»l, 



o 

the value of a is easily found: 

(29) a = - a (sin h a)-^ 



The spatial mean value of cos P, say cos P, for the magnetons of Group 
A will be required later. From (28) : 

1 



(30) cos /9 = coth a 

a 



The spatial mean value of cos B, say cos 0, for aU the N magnetons 
will Ukewise be required later. 

With a view to finding cos $ we first find an expression for co:3 $ in 
terms of the distribution variables A, F and p. 

Since $ ^ 6 + P, wo have : 

cos $ = cos 8 cos /? — sin 5 sin p; 

and from (25) : 

P+K«-A» v/(2FK)«-(P+K«-A«)». 

'"^'^ 2FK ' ''''' ^FK ' 

therefore: 

eoB « = y=.{(P+K»-A«) co8/S-V(2FK)»-(F+K»-A*)« sin p\. 



46 PARA' AND DIAMAGNBTISM: WILLS 



An expression for cos is obtained by multiplying the right hand mem- 
ber of (28) by this expression for cos $, integrating over all values of the 
distribution variables and dividing by N. It is tiius found that: 

_. 1 ?w(A) * ; 5« ( F + K*- A»)dF J. .CO. (I . ''r^ 

COB = — J — T- dA J i^i Je sm/9co8/9d/3jd^ 



8» •J A ±(X_K) 



(31) 



J_ f w(A) ^ r« V (2FK)« - (F« -K*~ A*)* dF 
X J*e sin /S cosf ^ - pjdfifd^, 





where the + sign in the lower limit of the integrab with respect to the 
variable F is to be taken if A > K and the — sign if A < K. 
Now the integral 

/aeo«/l X 

e sin /3 cos (- - j8) d/9 

2 

is proportional to the magnetisation of the magnetons of Group A in a 
direction perpendicular to that of the resultant field F and this mag- 
netisation must, on grounds of symmetry, vanish. 

Consequently from (31), after integration with respect to and P 
and the introduction of the value of a from (29), we have finally: 

(32) coe(?- J-^'dA/(cotha..-)( ) dF, 

mF 
where (a = -^. 



No further progress toward the evaluation of cos B can be made until 
the probability function w(A) has been determined. 

The statistical problem here presented has been solved by Gans.^ 
For the argument the reader is referred to the original paper; it is some- 
what lengthy and only the result will be given here. 

It is found that: 

4tA» --^ 
(33) w(A)= ==e ^^, 

V^T Ao' 

where Ao is a constant representing the most probable value of the 
molecular field A. 

^Gans: Ann, <2. Phya. 50, p. 163; 1916. 



PARA' AND DIAMAGNETISM: WILLS 47 

Under the assumption that there is one magneton per molecule: 

where ti is the magnetic moment of a magneton, M the molecular 
weight, No the Loschmidt number, p the density and s the nearest 
distance of approach of two magnetons. 

Inserting in (32) the expression for w(A) given by (33) we obtain for 
the mean value of cos $ the following expression: 



00 A+K 

A« 



(35) 



oos0=:^Je---MAJiooth^-l) ^ + ^ ^' )dF, 



o MA-K) 



where ^^"'kT^' 

and the + sign in the lower limit of the integral involving F is to be 
used if A > K and the — sign if A < K. 

The Distribution Function in Quantiun Theories of Paramagnetism. 

The general law of distribution for the statistical variables of a system 
of similar units, which is expressed by equation (1) of the present section 
is a result of classical statistical theory which presupposes that the 
energy associated with any degree of freedom of a unit is capable of 
continuous variation. 

It will appear, however, in Sect. VII of this review that to arrive at a 
satisfactory theory of paramagnetism which will account for experimen- 
tal results at low temperatures it is necessary to replace the assimiption 
that the energy associated with the various degrees of freedom of the 
rotating magnetons is capable of continuous variation by one which 
requires the energy to vary in accordance with Planck's quantiun 
relation, e = hu. 

It becomes necessary, therefore, to modify appropriately the law of 
distribution furnished by classical statistical mechanics in order to 
take account of Planck's quantum specifications relating to the energy 
associated with any degree of freedom of the rotating magnetons. 

The problem of quantitization here presented is quite similar to that 
worked out by Planck in the derivation of his law of black body radia- 
tion but is considerably more complicated, as will appear in the discus- 
sion given in Sect. VII. 

Further consideration of this matter is deferred until that section is 
reached. 

The results obtained in the present section will be of service in con- 
nection with the discussion of certain theories of dia- and paramagnetism 
which will be considered later. 



48 PARA' AND DIAMAGNETISM: WILLS 

IV 
EARLY ATTEMPTS AT ELECTRON THEORIES OF MAGNETISM 

At the very beginning of the epoch covered by the present survey 
the foundations of the modem electron theory of matter were being 
rapidly laid. Investigations during the closing years of the preceding 
century furnished strong support to the view that the ultimate structure 
of matter is essentially electronic in nature. 

In particular the assiunption of an electronic constitution of matter 
was found competent to remove many outstanding diflSculties encoun- 
tered by Maxwell's electromagnetic theory in attempts to explain optical 
phenomena of dispersion. 

Impressed with the success of the electron theory in this direction. 
Professor W. Voigt,^ in 1902, was led to an investigation having for its 
object the determination of how far the electronic structure assumed for 
material bodies in the optical theory of dispersion could be made to 
serve in the explanation of the phenomena of magnetisation. 

About the same time Sir J. J. Thomson^ engaged in an investigation 
having the same object in view. His results were in accord with those 
found by Voigt somewhat earlier. 

On account of the importance of the results foimd by both of these 

investigators it seems worth while to outline the argument of one of 

them. 

Voigt's Attempt at an Electron Theory of Magnetism. 

In the elementary theory of dispersion it is assumed that the molecules 
of a material body contain a number of electrons which, in the absence 
of an external electric or magnetic field, are in stable equilibrium, or in 
orbital motion about equilibrium configurations, under restoring forces 
of quasi-elastic nature proportional to the displacements of the electrons 
from their equilibrium positions. In order to account for absorption 
the assumption is made that a dissipative force acts on each electron 
proportional to its velocity of displacement. In case the body is subject 
to an external electric field E and an external magnetic field H an 
electron will experience two additional forces: one proportional to the 
electric field intensity and one proportional to the vector product of 
its velocity and the magnetic field intensity. 

If (, 17, f be the rectangular coordinates of an electron with respect 
to its equilibrium position as origin its equations of motion will be: 

mf = -hf-k{ + eEi + -(iyH, - fH,); 

c 

(1) mi = - hi? - ki; + eE, + - (fHi - fH,), 

c 

mf hf - kf + eE, + ? «H, - i^H,), 

c 

1 W. Voigt: Ann, d. Phys., 9, p. 115; 1902. 

• J. J. Thomson: PhU. Mag, 6, Ser. 6, p. 673; 1903. 



PARA" AND DIAMAONETISM: WILLS 49^ 

where h and k are constants, m the mass of the electron and e its charge. 
These are the f imdamental equations of the elementary electron theory 
of dispersion, in which, however, the mutual effects of displacements of 
the electrons are not taken into account. 

Professor Voigt introduces at this point the following assumptions: 
I. The external electric field shall be zero. 

II. The external magnetic field shall be constant and chosen parallel 
to the z-axis. 
III. The dissipative constant h shall be zero, in order to correspond 
to Ampere's assumption of the existence of molecular currents encoim- 
tering no resistance. 

With these assumptions the solutions of equations (1) are respectively : 

f = ai cos (pit + ai) + a2 cos (pst + as), 

(2) 1? = ai sin (pit + ai) - a2 sin (pjt + 02), 

r = b sin (pt + /3), 

where ai, a2, ai, as, bi, fi, pi, p2, p are constants and : 

/k eH eH 

(3) P=V-, Pi = P-^> P'^P + ^c' 

the values for pi and p2 being approximate, in accordance with the 
assmnption that the square of the natural periodicity p of the electron 
is large in comparison with the quantity (eH/2mc)'. 

As regards the initial conditions, the interval of time required for the 
establishment of the external magnetic field is supposed to be extremely 
small and its establishment is supposed to occur in such a way that the 
effects of the electric field, necessarily present during the period of 
establishment of the magnetic field, may be ignored.^ To the order of 
approximation specified in the previous paragraph it may then be 
assumed that the configuration and the velocity of an electron is un- 
changed during the period of establishment of the external magnetic 
field. 

Accordingly, we shall have, from (2), for the initial component dis- 
placements of the electron: 

fo = ai cos ai -|- aa cos aj, 

(4) 71^ = ai sin ai — as sin at, 

fo = b sin /3; 

and for the component initial velocities: 

f o = ~ Pi *i sin ai — P2 as sin at, 

(5) i;^ = pi ai cos ai — P2 aa cos as, 

f o == pb cos p. 

1 It will appear later that the effects thus ignored are of fundamental importance ii> 
Langevin's theory of diamagnetism. 



50 PARA' AND DIAMAGNETISM: WILLS 

We now suppose the electron under consideration to be contained in a 
small element of volume, dr, of a material body and that the origin O 
of our system of coordinates is also contained within the element. 

In order to test the magnetisation of the body we shall inquire as to 
the magnetic force due to this element at a point P on the Z-axLs in 
the neighborhood of the element. We first need to find an expression 
for the magnetic force at P due to a single electron. It will, in fact, 
suffice to confine ourselves to the consideration of the z-component of 
this force. 

Denoting OP by D, and supposing D large in comparison with OQ, 
this component force, to second order approximation in the small quan- 
tity f/D, from (11), Sect. I, may be expressed by: 

<6) ^•(^f"^^^^^ + D^- 

If Z denote the mean value in time of this expression, we find, with 
the aid of (2), that: 

Z = ^ (Pi »i* - Pt at*)- 
or, after substituting the values of ai' and at' obtained from (4) and (5) : 

(7) Z =^{(Pi - P2)tto* - O- PiPatto + %) + 4ppi(iiot-i)i|o} 

Noting the values of pi, pt and p given by (3) this equation is seen to 
reduce to: 

(8) z - ^ [(.,,-,4o- ^{ f (e.«+v) -^ (e.«+o }]• 



For brevity let: 



e * ' 



(9) *.o=^(C + 0, 

m * 

Here, evidently, Z^ is the value of Z before the application of the mag- 
netic field H; ^so is the potential energy of the electron due to its dis- 
placement perpendicular to the z-axis at the instant (t = 0) the field is 
applied; and "^^ is its kinetic energy at the same instant due to its 
motion perpendicular to the z-axis. At any time later the corresponding 



PARA- AND DIAMAGNETISM: WILLS 51 

potential and kinetic energies will be denoted by ^^ and ^|. Using the 
abbreviations given by (9) equation (8) may be written: 

This equation expresses the difference between the z-components of 
the mean value in time of the magnetic force at P due to the motion of 
the electron at Q before and after the application of the magnetic field. 
For present purposes what is required is the mean value of Z — Z^ due 
to the spatial distribution of the electrons in an element of volume 
dr at 0, of which electrons the one considered above is typical; and to 
find this, the mean value in space of "9^ — ^^ for the electrons in the 
element dr is required. These electrons are assumed to be originally 
quite uncoordinated in configuration and motion. 

Under no magnetic field the orbit of the typical electron will be 
elliptical, and-the equations of the path of its projected motion on the 
xy-plane will be: 

(11) f = a cos pt, v = fi sin pt; 

so that: 

f = — pa sin pt, i; = p/3 cos pt; 



and hence: 



m k Ic 



It follows, then, that at the instant the magnetic field is applied: 

(12) ^«, - *«, = 2^ - a') cos 2pt. 

Equation (11) is typical for a large number, N, of electrons in the 
volume element dt. Let dt be the time of description by the typical 
electron of an element of its orbit of which the projection on the xy-plane 
is ds. At any instant the probability that the electron will be on this 
element of its orbit will be dt/T where T is the periodic time in which 
the electron describes its orbit. The "expectation," then, for the num- 
ber of the N electrons which will be in the same element of phase in 
their respective orbits as that defined in position and magnitude by 
the element ds in the case of the typical electron will be Ndt/T; and 
hence the mean value, q, in space of any conmion quantity, q, associated 
with each of the N electrons will be expressed by: 



1 1 

1 /• Ndt If,, 



52 PARA' AND DIAMAGNETISM: WILLS 

Therefore, if the left hand member of (12) be taken for q: 

T 

^.o-^.o=^/(^.o-*Jdt. 

o 

The right hand member of this equation vanishes by virtue of (12), 
and hence the expression on the left also vanishes. From (10) it now 
follows that: 

<13) Z = Zo. 

Consequently, in accordance with the present theory, if the body in 
question were originally unmagnetised, it would remain so upon the 
application of a magnetic field. 

A medium with the electron structure assumed in the elementary 
theory of dispersion thus fails to account for either para- or diamagnetism 
when the electrons are supposed to move in their orbits without dis- 
-sipation and without collisions. If dissipation be assumed it is necessary 
to the existence of a steady state that the electrons receive through 
collisions accessions of energy. The question then arises as to whether 
under these conditions the magnetisation due to the motion of the 
electrons will be different with, and without a magnetic field. 

As far as the answer to this question is concerned dissipation in a 
sense may be ignored. For the effect of dissipation on the motion of 
the electron will be compensated by the continually recurring collisions, 
which for simplicity are supposed instantaneous. Now in the theory 
of dispersion the time of description of its orbit by an electron is very 
-small and it is therefore here assumed that an electron will describe 
its orbit many times between successive collisions. 

In the discussion which precedes it was shown that the difference, 
Z — 2m, between the z-components of the mean value in time of the 
magnetic force at P due to the motion of the typical electron with and 
without the magnetic field H depends simply upon the difference 
^M ~ ^M of its potential and kinetic energy due to its displacement and 
nM)tion perpendicular to H at the instant the magnetic field is applied. 
In the case now under consideration, where collisions are taken into 
account, it is therefore easily seen that the effect of a collision of the 
typical electron moving in the constant field of strength H is to change 
the value of Z — 25o given by (10) to a new value given by: 

^''^ z - Zo = - 2-^^ (*.. - *.o. 

where ^n and "^zi are respectively the potential and kinetic energy at 
an instant just after the collision due to the displacement and motion 
-of the electron perpendicular to H. 



PARA- AND DIAMAGNETISM: WILLS 53 

If the collisions are quite at random, then, in the case of isotropic 
bodies at any rate, the mean value of 2m due to the motions of the 
electrons in an element of volume dr at O must vanish, since magnetisa- 
tion would require the presence of a magnetic field. Hence to obtain 
the mean value of Z we have only to ignore Zo in (14) and find the mean 
value in space of the right hand member of this equation. Hence, 
if n denote the number of electrons per unit volume of the type con- 
sidered: 

— e*Hndr - 

^'^^ ^ ' - 2S^^D» ^*-> - *•»>• 

Assuming completely uncoordinated configurations and motions of 

the electrons ^.i is two thirds of the mean potential energy, and ^.i is 
two thirds of the mean kinetic energy of the electrons reckoned for 
configurations and motions just after collisions. If ^i and ^i denote 
respectively the mean potential — ^and the mean kinetic energy per unit 
volume for these configurations and motions, then: 

,7 e«Hdr , 

But this is equal to the magnetic force which would be produced at the 
point P by a small magnet at O with its axis in the direction OP and 
with a moment 

e'Hdr 

Hence, if M be the magnetic moment per unit volume: 

^''^ ^ = ^<*'-*>>' 

and, if «c be the volume magnetic susceptibility: 
(17) K = -^— (*i - ^0. 

It appears, from the result expressed by equation (17), that with 
the assumptions of the present argument it is possible to account for 
both para- and diamagnetism in a medium having the same electronic 
structure as that which serves so well in the optical theory of dispersion. 
Moreover, the present theory does not require for the explanation of 
para- and diamagnetism two essentially different fundamental assump- 
tions, as is the case in the older theories of Ampere and of Weber. 

The theory of Voigt leaves open the way to explanation of the ex- 
perimentally well known variations of magnetic susceptibility with 
changes in the physical state of the medium, through the variations in 
the circumstance of collision which such changes of state entail. Our 
knowledge, however, of what excites and maintains the motion of the 



54 PARA- AND DIAMAGNETISM: WILLS 

electroDfi is far too scant to enable the theory to predict how any par- 
ticular medium will behave under the action of a magnetic field. 

Sir J. J. Thompson, in his theoretical investigation of the magnetic 
properties of a material witii a molecular structure in which electrons 
are supposed to be grouped in rings with the electrons in any ring 
spaced at equal distances around the ring and rotating with a conunon 
angular velocity in a plane about an axis through its center, arrived 
at the result that, unless the electrons were subject to loss of energy 
through dissipation, the material would show neither dia- nor paramag- 
netic quality. This is in agreement with the negative result foimd by 
Voigt with the method outlined above. In the case for which dissipation 
is assumed it was found that paramagnetism would result. 

The difference between the magnetic properties of electrons describing 
free orbits with no dissipation, in accordance with the analysis of Thom- 
son, and the constant molecular currents assumed by Ampere, appears 
from the analysis of Thomson to be due to the fact that in the case of 
the electrons describing free orbits with no dissipation dia- and para- 
magnetic effects just cancel each other. 

Having been led to the negative result stated above, Thomson, in 
the same paper (1903), suggested that the magnetic properties of a 
substance may depend upon the properties of aggregations of largQ 
numbers of molecules. In the light of the trend of ideas in the subse- 
quent development of theories of magnetism a quotation is warranted: 

"In the case of such aggregations, however, we may easily conceive 
that the orbits of charged bodies moving within them may not be free, 
but that in consequence of the forces exerted by the molecules in the 
aggregate the orbit may be constrained to occupy an invariable position 
with respect to the aggregate — as if, to take a rough analogy, the orbit 
was a tube bored through the aggregate, so that the orbit and aggregate 
move like a rigid body, and in order to deflect the orbit it is necessary 
to deflect the aggregate. Under these conditions it is easy to see that 
the orbits would experience forces equivalent on the average to those 
on a continuous current flowing around the orbit; the aggregate and its 
orbit would imder these forces act like a system of littie magnets; and 
the body would exhibit magnetic properties quite analogous to those 
possessed by a S3rstem of Amperean currents." 

There is here a suggestion of a possible modification of the molecular 
structure assumed in the optical theory of dispersion which might be 
competent to account for the magnetic properties of material bodies. 
The direction is indicated along which electron theories of magnetism 
might naturally develop, while retaining the Amperean conception of a 
magnetic molecule with currents circulating without resistance within it 
in orbits which are in rigid connection with the molecule itself. 

An important advance in this direction was made by Langevin in 
1905. 



PARA- AND DIAMAGNETISM: WILLS 55 

V 
THE THEORY OF LANGEVIN 

The electron theory of magnetism proposed by Langevin^ in 1905 dem- 
onstrated that with a suitably conceived magnetic molecule or magneton 
it is possible to account satisfactorily for both dia- and paramagnetism. 

The basic ideas upon which the theory of Langevin rests have been 
adopted in nearly all theories of magnetism developed since 1905. 
This theory is therefore reviewed below in some detail. 

A magnetic molecule as conceived by Langevin contains a number of 
electrons of which some are negative and some positive, the algebraic 
sum of the charges on all the electrons in a molecule being ssero. Some 
of the electrons are supposed to be in orbital motion within the molecule 
in closed orbits and the planes of the orbits are supposed to maintain, 
by virtue of internal forces, definite orientations with respect to the 
molecule as a whole. The arrangement of the orbits may possess such 
a degree of symmetry that the resultant magnetic moment of the mole- 
cule is zero. On the other hand, if the arrangement fail of such sym- 
metry, the magnetic moment of the molecule will have a finite value. 

It will appear that the efifect of the application of an external mag- 
netic field to a body with a structure of such magnetic molecules is to 
accelerate the motions of the electrons in their orbits in a sense to produce 
diamagnetism. In case the magnetio moments of the molecules are 
not zero there will be superimposed upon this effect another, viz., an 
orientation of the molecules tending to line up their magnetic axes in 
the direction of the external field. 

In the following brief review of Langevin's celebrated paper of 1905 
changes in the notation have been made with the object of making it 
conform more nearly with that used above and vector methods replace 
cartesian. 

Diamagnetism. 

An examination of the properties of the molecular structure assimied 
by Langevin for diamagnetic isotropic bodies will show how it is com- 
petent to account for diamagnetism in such bodies. 

We consider a small element of volume of such a body which for gener- 
ality is supposed to be in motion. The element is supposed to contain 
a large number of electrons, some of which, at any rate, are in rapid 
orbital motion about the centroids of the molecules to which they belong. 
Let O, Fig. 4, be the centroid of these electrons, moving with velocity v, 
and let (x, y, z) be a S3rstem of rectangular axes whose directions are 
fixed in space but whose origin coincides with O at the iostant under con- 
sideration. Let Q(x, y, z) be the position of a typical electron, C(a, b, c) 

^ Ann, de Chim, et de Phys, Ser. 8, t. V, p. 70; 1905. 



56 



PARA' AND DIAMAGNETISM: WILLS 



the centroid of the molecule to which this electron belongs; and, with 
reference to O, let r be the position vector of Q, and q that of C; while 
8 is the position vector of Q with reference to C. 

Assuming the element to be electrically neutral and unpolarized we 
have: 



(1) 



Ze « 0; Zes « 0. 



Since O is the centroid of the element, Zx = 
Zy = Zz » 0; and, since it is isotropic: 



(2) 



Zxy = Zyz = Zzx * 0, 
Za = Zb = Zc « 0, 
Zab » Zbc " Zca » 0. 




It then follows, if (, 17, f be the coordinates of 
Q with reference to C, that: 

(3) Zf = Ziy = Zt = Z{i, = Zi,r = Zi|f - 0, 

where the summations are to be taken over 
all the electrons in the element. 
As far as the mean magnetic field of the electron is concerned the 

electron at Q, due to its motion with velocity s about the centroid C, is, 
from (12) Sect. I, equivalent to a small magnet whose moment is 



Fig. 4 



(4) 



2c^^^' 



and, if M be the magnetic moment of the element of volume due to all 
the electrons of a given type within it, say classical negative electrons, 
then: 



(5) 



M = — Zsxs, 
2c • 



where the summation is over all the electrons of the type considered. 

By differentiation with respect to the time we find for the time rate of 
change of this quantity: 



(6) 



e 

M =* —Zsxs. 
2c 



If F be the force on the typical electron due to the action upon it 
of the rest of the molecule in which it is situated, B and H the electric 
and magnetic force, respectively, of external origin, we shall have from 
the equation of motion of the typical electron: 



(7) 



ms = F+eE + - (v + s) xH - mq - mv, 



where e is the charge of the electron and m its mass. 



PARA' AND DIAMAONETISM: WILLS 57 

Here the quantities F, E, and H all refer to the point at which the 
typical electron is situated, but, since the element of volume is small, 
they may be expressed as follows: 

F =Fo + (s.VF)o + ...., 

(8) E =E, + (s.VE), + ...., 

H = H„+(s.VH)^ + 

where the zero subscript indicates that the corresponding quantity 
is to be evaluated at O, the centroid of the element. 

From (6), (8), (2), and (3) we obtain, upon neglecting terms of higher 
order than the first in the small quantity s, writing 

(9) Z? = Zi,« = 2f« = -' 
and dropping the zero subscripts: 

(10) M = ;^2)sxF+;^y(curlE + - vdivH- -vVH)-- — H>» 
^ ^ 2mc 4mc I c c c dt j 

in which the vectors and their space derivatives refer to the point O. 
Now, from Maxwell's field equations: 

J. rx .X i« l^H 1/ „„ dH\ 

divH = 0; curlE=-^-«.(vVH--j; 

and consequently the preceding equation reduces to: 
<11) M = 4ssxF-£^|(IH). 

The first term on the right represents a time variation in M due to 
the action of the internal forces of the molecules; this vanishes if , as in 
Langevin's theory of diamagnetism, each molecule has no initial mag- 
netic moment. 

If AM denote the change in the magnetic moment of the element due 
to the establishment of the external field within it, then, by integration 
of the last equation: 

(12) AM=--^,IH. 

4mc* 

Owing to the creation of the external field within it the element thus 
acquires a diamagnetic moment. 

It may be noticed that in the expression for AM the charge of an elec- 
tron appears as a square. Consequently, if positive as well as negative 
electrons are in orbital motion within the molecules, they, too, will 
give rise to diamagnetism in accordance with (12). On accoimt of the 
large mass of the positive electron, however, the contribution of the 



68 PARA' AND DIAMAGNETISM: WILLS 

positive electrons to diamagnetism would probably be very small in 
comparison with that of the negative. 

For the quantity I we may write nk^, n being the number of electrons 
in the element of volume and k' the square of the radius of gyration of 
the mean configuration of the electrons in a molecide with respect to 
an axis through their centroid. From (12) we then have: 

(13) AM = --^k«H. 

4mc* 

From (14) Sect. I, the mean absolute value of the components of the 
magnetic moments of the n orbits in the direction of H, say Mh» ^^ ^ 
given by: 

eS 

(14) Mh = ~ cos ^, 

CT 



where cos B denotes the mean value of cos 9, 9 being the angle between 
n and H. 

From (13) the change in m^i ^ay Am^, due to the creation of the mag- 
netic field H will be given by: 



e* 



It follows from (14) and (15) that the ratio of A^h to Mh niust be 
very smaU for aU attainable field strengths; in fact less than 10^^ if 
T be assumed of the order of the period of light vibrations, say 10"" 
seconds. 

If «c be the magnetic susceptibility per unit volume and N the number 
of electrons per unit volume, then, from (13): 

where p is the mass density of electrons per imit volume. 

In accordance with the argument advanced here all substances will 
possess the diamagnetic property. If the magnetic molecules of any 
substance possess initial magnetic moment of their own, they will 
possess paramagnetic as well as diamagnetic quality. If the initial 
moment be zero, no external action upon the molecule will produce one. 

The argument has left out of account any explicit reference to the 
effect of collisions among the molecules upon the diamagnetic state of 
the substance. It will be recalled, however, that there has been nothing 
assumed in the argument to prevent motion of the most general kind of 
the element of volume containing the ensemble of electrons; and hence, 
whatever be the motion of the ensemble, its diamagnetic state is at 



PARA- AND DIAMAGNETISM: WILLS 59 

each instant determined simply by its actual configuration with reference 
to the external magnetic field, and therefore is independent of collisions 
among the molecules. 

Again the argument does not take account of the interior forces of a 
molecule which may result from the diamagnetic action itself. But 
it will be seen presently that, in the mean, a diamagnetic modification 
implies only a change of velocity of an electron in its orbit without 
deformation of the orbit, and the absence of a mean deformation of 
the molecule due to a diamagnetic modification implies that the cones- 
ponding interior reactions due to it must be negligible. 

The fijdty of spectral lines lends important support to the view that 
the intramolecular motions of a substance depend but slightly upon 
the temperature; the comparatively slow thermal motions can therefore 
modify but very little the intramolecular motions giving rise to diamag- 
netism on the present theory. The diamagnetic property is thus 
practically independent of temperature, according to the experimental 
law of Curie. There are, however, many exceptions to this law. 

An important question is that relating to a possible change in the 
area of the orbit of an electron due to the action of an external magnetic 
field. Let f (r) be the central force which holds an electron in its orbit, 
supposed circular. 

In the absence of an external field : 

(17) mcA = f(r), 

where w is the angular velocity of an electron in its orbit. 

If H^ denote the component of the external field perpendicular to 
the plane of the orbit, then, after the field is applied: 

m (o) + Aw)* (r + Ar) +-H„ea)r =f(r + Ar), 

c 

where Aoy and Ar are the variations in o) and r respectively due to the 
action of the field. Retaining terms of the first order only in the small 
quantities, Aciy and Ar, we therefore have: 

f' (r)Ar = 2mra)Aa) + ma9'Ar+ -HnCwr; 

c 

and hence : 

(18) (f' (r) - m«*} Ar » 2ma)rAa> + -H„e«r. 

c 

Now, if r be the orbital period and S the orbital area, then, using (14) 
and (17), Sect. I: 

Awr* c eS c e er* 

=^«-A- «-Am= — A(HScos^) = - — H„: 

2 e cr e ** 4irtnc ^ ^ 4mo^' 



60 PARA' AND DIAMAONETISM: WILLS 

and, therefore: 

H.e 
2mc ' 

(19) — 4ina)*Ar = 2ma)rAa) + -H^etfr, 

c 

From (18) and (19): 

(f'(r) + 3m«»}Ar-0. 
Thus, either: 

H.e 

(a) Ar - 0; Aw - "^ 

2mc 

or: 

(b) f'(r) - -3m«»- --* 

r 

If condition (b) ie satisfied, 

f _3 

r " r ' 
andhenoe: 

(20) f » ^ 

where K is a constant. 

Except, then, in the very special case that the central force holding 
the electron in its orbit varies inversely as the cube of the radius of the 
orbit, condition (a) will be satisfied, the effect of the magnetic field being 
simply to cause a variation of the angular velocity of the electron by 
the amoimt — Ho e/2mc. 

It is evident that the component of the magnetic force in the plane 
of the orbit will not operate to change the area of the orbit, since the 
displacements to which it gives rise are perpendicular to the plane of 
the orbit. 

The change of period, giving rise to diamagnetism, in the orbital 
motions of electrons within the atoms corresponds to the simple Zeeman 
effect in magneto-optics. 

It is of some little interest to compare the formulas (16) found for 
diamagnetism by Langevin with that which holds for a substance which 
is constituted of the spherical magnetons discussed in Sect. II. 

It was there shown that the effect of establishing an external magnetic 
field H within such a magneton was to change its magnetic moment by 
an amount: 

where Q is the moment of inertia of charge of the magneton and J its 



PARA' AND DIAMAGNETISM: WILLS 61 

ordinary moment of inertia with respect to an axis through its centroid» 
If the magneton be constituted of electrons of a single type, of mass m 
and charge e, symmetrically spaced about a positive nucleus then Q» 
ek* and q = mk^ where k is the radius of gyration of the electrons in the 
magneton. 

If, then, K be the volume magnetic susceptibiUty of the body con- 
stituted of such magnetons it follows from (21) that: 

Ne« 
jc = — -— - k^ 
4mc^ 

where N denotes the number of electrons per imit volume and p the 
mass density^ of the electrons. This result agrees with that expressed 
by (16). 

Paramagnetism. 

A body will exhibit paramagnetic quality in the presence of a mag- 
netic field in addition to the diamagnetism considered above when its 
magnetic molecules have individually other than zero magnetic moment. 
The theory appropriate to a paramagnetic gas was developed by Lange- 
vin in his paper of 1905. Later this theory was made the basis of a 
theory of ferromagnetism by Weiss. 

In Langevin's theory of a paramagnetic gas the magnitude of the 
magnetic moment of a molecule is supposed to be invariable under all 
conditions, the slight diamagnetic changes in its moment being ignored. 

It is of interest to examine first, as regards its general nature, the 
process whereby the paramagnetic state is set up when a gas is sub- 
jected to an external magnetic field. At the instant the field is appUed 
the diamagnetic state discussed above will be established immediately. 
The paramagnetic state, on the other hand, will require an appreciable 
time for its establishment. 

At the instant the magnetic field H is appUed a magnetic molecule 
acquires potential energy with respect to the field of amount 

-H dv 

where if is its magnetic moment. This increase in the potential energy 
of a molecule is derived initially from its kinetic energy of rotation, 
just as the potential energy of a molecule of a gas subjected to a gravita- 
tional field is acquired from its kinetic energy while it is rising in the 
field. Now the result of this partition of kinetic energy among the 
various degrees of freedom (translation and rotation) of the molecules ia 
incompatible with thermal equilibrium. It is in the process of the 
establishment of thermal equilibrium through collisions that para^ 
magnetism makes its appearance. In this process magnetic energy is 
derived from the energy of thermal agitation of amount 

- Hdv. 



62 PARA- AND DIAMAQNETI8M: WILLS 

If the molecules have no other potential energy relative to their 
orientation, as in the case of a gas and probably a liquid, in order to 
maintain the medium at a constant temperature it would be necessary 
at each instant to furnish to it an amount of heat energy per unit volume 
equal to — H.dl, if I denote intensity of magnetisation. In the case 
of a solid where the molecules have a potential energy of orientation 
it is only for the case of a closed cycle that a similar conclusion may be 
drawn. 

\^th the aid of the laws of thermod3mamics it is easQy shown that 
the magnetic moment M of a given mass of a paramagnetic substance 
in an external field of strength H must, in the case of a gas or a liquid, 
be a function of H/T: 



M 



-<f) 



where T is the absolute temperature. 

For a small reversible modification in which H changes by dH, and 
T by dT, the heat evolved, say dQ, which depends upon H, will be given 
by: 

dQ.H(-dH + -dT). 

Since the modification is reversible dQ/T must be a perfect 
and hence: 



A/1 ^^ . ^/l ^\ 
dT\T dH/ dH\T dT / ' 



from which it follows directly that: 



dT dH 



The integral of this equation is given by : 
(22) M = f (ly 



which is the result it was desired to prove. The argument is readily 
extended to show that this result will also hold for a solid body, pro- 
vided its internal energy does not depend appreciably upon H. 

Thermodynamics alone will not permit of the determination of the 
function f . For many substances experiment shows M to be directly 
proportional to H and this, with the result expressed by (22), if the 
conditions stated are satisfied, leads to the result: 

(23) M = -H 

where A is a constant independent of T. 



PARA- AND DIAMAGNETISM: WILLff 63 

In the particular case of a paramagnetic gas such as oxygen the form 
of the function f may easily be determined. 

Theory of a Paramagnetic Gas. 

In his theory of a paramagnetic gas Langevin assumes each of the 
magnetic molecules to have a magnetic moment, Mj the magnitude of 
which is the same for all molecules. The direction of the magnetic 
axis of the molecule is then that of the vector m- Elffects due to the 
rotations of a molecule about axes perpendicular to its magnetic axis 
are ignored. The molecular magnetic field is also ignored, since it will 
certainly be very small for gases under ordinary conditions. 

The appropriate distribution function for this case, as Langevin 
showed, is give n by (22) Sect. Ill; and from (23) of the same section 
the mean vdue, cos 6, of the cosines of the angles made by the magnetic 
axes of the molecules with the external magnetic field H is expressed by: 

1 ^H 

(24) cos ^ = coth a ; (a = — ), 

a ic X 

where k is Boltzmann's constant and T the absolute temperature. 

On grounds of Efymmetry I, the intensity of magnetisation, must be 
in the direction of the external field H; and it must be equal in magnitude 
to the sum of the projections of the moments of the individual molecules 
in imit volume in this direction. Accordingly I will be given by: 



I « MU cos ^ 
(^^^ = Mn (coth a - i) 

where n denotes the number of magnetic molecules per unit volume. 

From this result it appears that I is a function of H/T as re- 
quired by thermodynamics and, moreover, owing to the factor n, that 
it is directly proportional to the pressure of the gas. 

When the bracketed expression on the right of the expression for I 
takes on the value unity I will assume its maximum vsdue, ^n, De* 
noting the maximum value of I by lo, from (25) : 

(26) I = lo (cosh a - -). 

a 

The curve in Fig. 5 shows the manner in which I/Io varies with a» 
It will be seen presently that imder ordinary conditions of experiment 
a will be quite small for oxygen; in fact of the order 10~*. 

When a is small I/Io will vary directly with H. At low temperatures, 
however, and for powerful fields a may become so large that the relation 
between I/Io and a becomes non-linear. 



64 



PARA" AND DIAMAONETISM: WILLS 



From (26), by development of coth a in ascending powers of a, neg- 
lecting powers of higher order than the first: 



(27) 



I - I.|. 



with sufficient approximation under ordinary conditions of experiment; 
and, if K be the coefficient of volume magnetic susceptibility: 



(28) 



3kT' 




•• «. 



Fio. 5 



showing that k varies inversely with the temperature in accordance 
with what is known as Curie's law of paramagnetism. 

The preceding theory may 
Also be valid for a medium other \r 
than a polyatomic gas, such as 
oxygen, when the energy of ro- 
tation of the molecules is known 
to be a function of the tempera- 
ture, in accordance with thermo- 
d3mamic theory. In all such 
cases it is only necessary that 
the energy of rotation shall be 
proportional to the absolute 
temperature in order that the 
theory may be applicable; the 
•quantity k only will have to be modified. 

All magnetic substances for which the mutual actions among the 
molecules are negligible, such as solutions of paramagnetic salts, should 
have magnetisation curves exactly similar. 

The expression for k given by (28) may be written: 

since lo = n/i, and p == nkT, p being the pressure of the gas. 

At normal pressure, and at the temperature O^C, Curie found for 
oxygen: 

K = 1.43 X 10-^ 

It follows that the maximimi intensity of magnetisation for oxygen 
will be given by: 

lo « (3 X 10» X 1.43 X 10-^* = 0.65. 
For liquid oxygen, therefore, with a density 500 times greater, a value 
of I > 325 might be expected. 



PARA- AND DIAMAQNETISM: WILLS d6 

The order of a for oxygen under ordinary conditions of experiment 
may now be found. We have: 

a ^ _ ___ ™^ • 
nkT p 

The value of I found above for oxygen under nonnal conditions was 0.65. 
Hence: 

a « 0.65 X 10-*H; 

for a fairly powerful field, H » 10,000 say, and then: 

a = 0.66 X 10-«. 

If it be admitted that the magnetic moment m for a molecule of oxygen 
is due to a single electron with a charge equal to that of an atom of 
hydrogen in electrolysis rotating in a circular orbit of radius r equal to 
1.5 X 10~* cm., the velocity of the electron may be calculated as follows. 
Since, from (14), Sect. I, 

_ eS _ evr 
'*■" ci^ " 2c' 

where S is the area of the orbit, r the periodic time and v the velocity 
of the election, we shall have: 

1^ = 11/4= ^°®^- 

Now e, being expressed in electrostatic units, 

ne 

- « 0.40; 

c 

and since under normal conditions, as found above, lo » 0.65, it follows 
that: 

^ «. ^ .^ 1-5 X 10^ 
0.65 - 0.40 X — X V, 

from which: 

V = 2 X 10* cm/sec. 

This velocity is of the same order as that which an electron would 
have in stable circular orbital motion about a positive charge of equal 
magnitude placed at the center of the orbit. For in this case: 

mv* e* . e* 

=-- , V* = — -. 

r r* mr 



66 PARA' AND DIAMAGNETISM: WILLS 

from which: 

V = 10" cms/sec. 

It is worthy of note that the resultant magnetic moment of a molecule 
of oxygen may be accounted for by the orbital motion of a single electron; 
this would also be true for a molecule of iron, for which the maximum 
magnetisation per molecule is of the same order as that for oxygen. 

In the case of the magnetisation of a paramagnetic gas such as oxygen, 
we have seen that the kinetic energy of the molecules furnishes per 
unit volume during the period of rearrangement (which results in the 
appearance of paramagnetism) an amoimt of energy 

- /H.dl; 

so that the energy per unit volume of the medium is augmented by an 
amount 

2 

The gas must therefore be heated by an amount which may be cal- 
culated as follows. 

Suppose the volume to remain constant and let AT be the rise in 
temperature due to magnetisation, then: 

CAT ^Kw. 
2 

C being the specific heat at constant volume. Now, approximately, 
in C. G. S. units: 



and, therefore, 



C = 10^ K « 1.43 X 10-^ 



AT = 0.8 X 10-"H«. 



From this result, for H = 10,000, AT « 10r*C; while for H = 
40,000, AT - 10"* C**. This elevation of temperature would vary 
directly with the susceptibility «, and therefore inversely with the abso- 
lute temperature. 

In concluding this somewhat brief review of Langevin's theory the 
following remarks may prove to be of interest later. 

His theory of paramagnetism is what may be termed an equipartition 
theory ; for it is based on classical statistical theory that leads to equipar- 
tition of energy among the statistical coordinates of a system which 
appear only as the sum of squares in the energy function of a statistical 
unit. 



PARA' AND DIAMAGNETISM: WILLS 67 

The property of pennanancy is given to the magnetic moments of 
the molecules; for example, these moments are not subject to variation 
with temperature. 

The effects of intra-molecular forces have been ignored, thus restricting 
the range of application of the theory to paramagnetic gases. 

By ignoring the effects due to rotations of the molecules about axes 
perpendicular to their magnetic axes they are deprived of gyroscopic 
properties which, as we shall see, may play an important role in magneti- 
sation. 



68 PARA" AND DIAMAGNETISM: WILLS 

VI 

MODIFICATIONS OF THE THEORY OF LANGEVIN INDEPENDENT 

OF QUANTA HYPOTHESES 

The theory of Langevin, as we have seen, leads in the case of diamag- 
netism to the result that the diamagnetic susceptibility of all bodies 
should be independent of the temperature and the field strength; and in 
the case of paramagnetism to Curie's law, which requires the suscepti- 
bility to vary inversely with the absolute temperature. 

Now many of the experimental facts found since the time (1905) of 
publication of Langevin's theory are not in accord with these results. 
Consequently various attempts at modification of the theory have been 
made. In the present section we shall consider modifications of the 
Lang^vin theory which do not invoke the aid of quantum h3rpothe8e8. 

Theory of Honda. 

Eotaro Honda^ in 1914 proposed a modification based upon the follow- 
ing two assumptions: 

(a) — The magnetic moments of molecules are not constant but depend 
upon the temperature. 

(b) — The molecules exert mutual forces upon one another, the ten- 
dency of which is to prevent their lining up in the direction of the 
external field. 

A magnetic molecule in the case of a soUd is supposed by Honda to 
consist in general of an aggregate of a number of actual molecules, 
such aggregates being subject, however, to the usual laws of thermal 
molecular motion. In accordance with assumption (a) the form of a 
molecule is supposed to depend upon the temperature; a change in form 
involving at the same time a change in the value of the magnetic moment 
of the molecule. Thus the form of the molecule of a body in the ferro- 
magnetic state is assumed to be spherical, so that it shall not be subject 
to orientation through thermal impacts. In the ferromagnetic range 
of temperatures the small mutual forces only will be operative in opposing 
the tendency of the magnetic molecules to hne up with their axes along 
the direction of the external magnetic field, and in consequence a large 
magnetisation results in this case. In the passage from the ferromagnetic 
state to the paramagnetic the magnetic molecule is supposed to pass 
from the spherical to an elongated form, with the result that a large 
thermal action opposing the lining up of the molecules becomes operative, 
and consequently the body passes from the ferro- to the paramagentic 
state. The energy of deformation of the molecules in this process 
together with that required by the new degrees of freedom is supposed 
to account for the heat absorbed in the process of transition. 

1 K. Honda, Tokio, Sci. Rep. 3. p. 171; 1914. 



PARA' AND DIAMAGNETISM: WILLS 69 

The distribution function proposed by Honda, incorporating the 
assumptions (a) and (b), is: 

Mof(T)H ^ 
a e r-zi— — cos 0, 
kT + « 

where /iof(T) represents the magnetic moment of a molecule, /io being 
the value of this quantity at absolute zero, and is a constant or a 
function of the temperature expressing the mutual action of the molecules 
upon one another. This distribution function of Honda reduces to 
that of Langevin if f (T) = const., and = 0. 

The symbols other than fiJl{T)j and 4> have the same significance as 
in Langevin's theory. 

The function 4> which expresses the mutual action of the molecules 
represents an effect which, like thermal action, tends to hinder the 
lining up of the molecules with their axes in the direction of the external 
magnetic force, and hence is added to ihe temperature factor kT. 
In paramagnetic bodies is in general small in comparison with kT 
and only becomes of importance at low temperatures. 

The modified distribution function leads to an expression for the 
magnetic susceptibility which is in good agreement in many cases with 
the experimental results of K. Onnes and A. Perrier at low temperatures 
and also with other experimental results at higher temperatures, when 
appropriate choice of the temperature functions f and are made. 

The theory is also applied with some success to the explanation of the 
paramagnetic behaviour of ferromagnetic substances at temperatures 
above the critical temperature. 

The functions f and are not capable of determination from theoretical 
considerations, and the theory suffers chiefly from this deficiency. 

Theories of R. Gans. 

In a series of papers beginning in 1910 R. Gans^ * ' ^ has made suc- 
cessive attempts toward the improvement of theories of dia- and para- 
magnetism beyond the point reached by Langevin in his paper of 1905. 

The progress made by Gans in this connection may perhaps be satis- 
factorily estimated from a brief review of two of his papers which ap- 
peared in 1916, entitled respectively "Theorie des Dia-, Para-, und 
Metamagnetismus,"* and "Uber Paramagnetismus."* 

In the former of these two papers he considers a material body 
supposed constituted of axial magnetons. The magneton itself is 
supposed to consist of a rigid system of classical negative electrons 

1 R. Gans: Oott, Naehr,, p. 197; 1910. 
tR. Gans: OoU, Nadir., p. 118; 1911. 
• R. Gana: Ann, d, Phya. 49, p. 149; 1916. 
« R. Gans: Ann. d. Phya. 50. p. 103; 1916. 



70 PARA' AND DIAMAQNETI8M: WILLS 

within a unifonnly charged positive sphere, the center of which 
coincides with the centroid of the system of negative electrons. The 
equatorial moments of inertia of the magneton, A and B, are supposed 
equal and the polar axis for which C is the moment of inertia is called 
simply the axis of the magneton. 

The angular velocities of rotation of the magneton are supposed so 
small that the resultant magnetic fields due to these rotations nuty be 
considered as linear functions of the corresponding angular velocities; 
and the accelerations giving rise to radiation to be so small that the 
energy radiated may be neglected. The magneton system may then be 
considered as quasiHstationary. Furthermore the inertia mass of a 
magneton is supposed to be entirely of electromagnetic origin. Finally, 
the molecular magnetic field is ignored on the present theory. 

For a body constituted of magnetons of the type here contemplated, 
either one or the other of the laws of distribution given respectively by 
(12) or (19) of Sect. Ill is applicable, depending upon whether or not 
the rotations of the magnetons about their individual axes of symmetiy 
are dependent upon or independent of thermal agitation. In the 
former case the law of distribution leads to a theory of diamagnetism 
and in the latter to a theory of paramagnetism. We consider the 
former case first. 

From (12) Sect. Ill, the appropriate law of distribution for this case is: 

__ « 

(1) dN »ae ^''^sintfdQ, 

where: 

(2) €«-^+~+r— (Psin*sin^ + Qcos«sin^ + Rco8^), 

2J ZL* 2mc 

and 

(3) dQ « dtfd^d^dPdQdR; 



the significance of all the quantities here involved is given in Sect. IIL 
The expression (1) gives the number of magnetons per unit mass 
whose statistical variables are delimited by the elementary phase domain 
do. Each of these will contribute to the magnetisation per unit mass 
an amoimt |^.H/H, |^ being the magnetic moment of any one of the 
magnetons of this group. 

If M denote the scalar value of the magnetisation per unit mass, 
then: 

(4) U'^nf^e'^BinedQ^fe^^mnedQ, 



PARA' AND DIAMAGNETISM: WILLS 71 

where the integratioD is to be taken over all values of the variables 
whose differentials occur in dl2 and is supposed performed after t^ .H/H 
is expressed in terms of these variables. 
From (60), Sect. II, with the aid of (7) and (8), Sect. Ill: 

~=- = b (P sin sin ^ + Q cos sin ^ + R cos ^), (b = r-—). 
H 2mc 

If we now let: 



/e-«* 



(6) Z = /e "^sin^dft, 

the expression for M may be put in the simple form: 

NkT d log Z. 



(6) M = - 



H dlogb 



By division of this expression by H we obtain for the susceptibility 
per unit mass, Xt the following expression: 

^^^ ^ H* dlogb 

For the case in which the rotations of the magnetons about their 
axes of symmetry are supposed independent of thermal agitation the 
appropriate law of distribution is given by (19), Sect. Ill: 

(8) dN -ae^sin^dO, 

where 

ps J. ^ e 

(9) e r=. /^ + -— H (P sin sin ^ + Q cos sin ^) — m H cos 9, 

2 J 2mc 

(10) do = d^ d^ d« dP dQ. 

Proceeding in a similar way to that foUowed in the case just considered 
the following expression is found for the susceptibility per unit mass: 

^ NkT/ d log Z' d log Z' \ 
^^^^ ^ ^ tf V(d log M d log b /' 

where 

(12) Z' = fe" " sin ^ dQ, 

€ and do being given by (9) and (10) respectively. 



n tAMU- JL%:^ LiAM^^a^m^M WILL^ 






IZ) Z»4i*v"2ykT//=c/e *** ■»#<». 



TUsnMnwmxknmammUjwomierzJ >C;J «C;a^J<C 



C«e 7-4 > C. 








U for btetitj wt 


spot: 






04; 


1 

y- 


tPV(J-C), 
2kT 






♦ (7) 






then from (13): 


4.»>/« 




'•i'c 


(15) Z - 


r V(2»kD»PC- 


# — C 



T 

Unog thk value for Z fonnulft (7) fmniriies for the magnetic auaoep- 
per unit 



X- -m/m + 



\ ^ 2J VV'-r^T) y/j 



This expreation aawimen a aunider fcMin if we let: 



(16) 



2 12 

°^^^"Vi7e^»(T)"7i'*'3' 



2 2 + C/J' 
whereupon we obtam: 

(17) X - - NW?^?^ {1 + h0(7)|. 

The quantity y defined above is at constant temperature proportional 
to the field strength, H, while I/t* at constant field strength is propor- 
tional to the absolute temperature, T. 

The susooptibility x> lus shown by the expression just found, depends 
upon the function tl(y) which may be calcidated with the aid of a table 



. i 



PARA- AND DIAMAGNETISM: WILLS 



73 



for the probability integral for assumed values of y and l/y. The 
variation of 0(7) with 7 (proportional to H) and of 0(7) with I/t* 
(proportional to the absolute temperature) are shown in Fig. 6 and Fig. 7 
respectively. 




From formula (17) it is seen that the susceptibility, Xoi ^i" very weak 
fields is given by: 



xrw2J+C 



and hence: 



X — Xo 



Xoh 



- «(7). 



In general, then, x depends upon the field strength and investigation 
brings out the fact that the curve showing the relation between the 
susceptibility and field strength is of the t3rpe shown in Fig, 8. 

In Fig. 9 is shown the type of curve obtained experimentally by 



Fig, 8 



H 



V. 



Fig. 9 



Honda for many diamagnetic substances. The experiments of Honda 
were not sufficiently extended in the direction of small field strengths 
to show whether or not his curves, if continued, would be of the type 
called for by the present theory. 

If the present theory in its main features is correct suitable quanti- 
tative measurements of the susceptibility would make possible the 



74 PARA' AND DIAMAGNETISM: WILLS 

derivation of valuable information as to the constitution of the magneton, 
as regards its size, shape, and moments of inertia. 

Case II— J - C. 

In this case all the principal moments of inertia of the magneton 
are equal, and hence h " 0, and 7 "» 0, so that: 

X - Xo - - Nb»J; 

the susceptibility is thus independent of both field strength and 
temperature. This is found experimentally to be the case with many 
substances. 

It is important to remember in connection with this case that although 
the principal moments of inertia of the magneton are assumed equal, 
this does not imply that the magneton is to be considered as a geometrical 
sphere. If this were the case the statistical method would be no longer 
applicable and the problem would become one of electromagnetism 
simply. 

Case III— J < C. 

The results found for this case are quite similar to those found for 
Case I and it is therefore not worth while to consider it in detail. 

Moments of Intertia of Diamagnetic Magnetons. 

As a result of an extensive series of experiments, H. Isnardi* reached 
the conclusion that diamagnetic susceptibility in general is quite inde- 
pendent of the field strength. If this be so the assumptions of Case II 
are warranted. The principal moments of inertia of the magneton 
may then be considered equal and the formula found for the suscepti- 
bility for this case may be used. 

Upon substituting for b its value e/2mc in this formula we obtain: 

where N is the number of magnetons per gram, e/mc « 1.77 x 10* 
electromagnetic units and J the moment of inertia of the magneton. 

Assuming one magneton to the atom, if No be Avogadro's number, 
and A the atomic weight. 

No = NA « 6.176 X 10"; 

and we obtain from the formula for x: 

J « - 2.067 X 10-«AX. 

> H. lanardi, Contribuci6n ai estudio de las eieneiaav Uniy. Naol. de La Plata.-^Aiifi. d. 
Phu9, 61, p. 685; 1920. 



PARA' AND DIAMAGNETISM: WILLS 



76 



From the experimental results foimd by Owen^ the values of J have 
been calculated by Cans' for various elements with the aid of this 
formula. These values together with the corresponding values for 
A and x are given in: 









Table I 








£3emeot 


A 


-xXlO» 


JX10« 
in g. ems'. 


Element 


A 


-xX10» 


JX10- 
in g. cms*. 


Be 

B 

C(Dia) . . 

8 

P 

Sa 

Cw 

Zn 

Ga 

Ge 

As 

Se 

Br 

Sr 


9.1 
11.0 
12.0 
28.3 
31.0 
32.07 
63.57 
66.37 
69.9 
72.6 
75.0 
79.2 
79.92 
87.62 


1.00 

0.7 

0.49 

0.13 

0.90 

0.49 

0.086 

0.166 

0.24 

0.12 

0.31 

0.32 

0.40 

0.2? 


1.88 

1.69 

1.22 

0.761 

6.77 

3.26 

1.12 

2.09 

3.46 

1.80 

4.81 

6.24 

6.61 

3.62? 


Zr 

^::::: 

In 

Sn(gray) 

Sb 

Te 

I 

Cs 

Pb 

Bi 


90.6 
107.9 
112.4 
114.8 
119.0 
120.2 
127 6 
126.9 
132.8 
197.2 
200.0 
204.0 
207.1 
208.0 


0.46 

0.20 

0.18 

0.11 

0.35ap. 

0.82 

0.32 

0.36 

0.10 

0.16 

0.19 

0.24 

0.12 

1.40 


8^43 

4.46 

4.18 

2.61 

8.61ap. 
20.4 

8.43 

9.46 

2.76 

6.12 

7.86 
10.1 

6.14 
60.2 



It appears that the values for the moments of inertia for the various 
substances are all of the same order of magnetude. These values are 
considerably less than those found for paramagnetic substances, as 
will appear later. 

In this connection it should be remarked that Isnardi's conclusion 
that diamagnetic susceptibilities are in general independent of field 
strength, is not fully supported by the experiments of Frivold.' 

Paramagnetism and Metamagnetism. 

Formulas (11) and (12) are those required for the explanation^of 
para- and metamagnetism. 

From (12), after integration with respect to P, Q, ^, 4>, and the 
substitution of x for cos 6, we obtain: 



(19) 
where 

(20) 



■*"i tt«(l-x«) ax. 

Z' = 8ir»kTj/e e dx, 

-1 



2i_2 



2 kT 



a = 



kT 



* M. Owen, Ann, d. Phy». 37, p. 664; 1912. 

> R. GanB, Ann. d. Phys. 61, p. 163; 1920. 

« O. E. Frivold, Ann. d. Phy$. 57, p. 471; 1918. 



76 



PARA' AND DIAMAGNETISM: WILUS 



The expression (19) after integration with respect to x may be 
written in the form : 



(21) 



Z' » 4 ir»V5i- kTJ 



e 



a« +T« 



{*(r + a) -*(r-.a)), 



where. 



T> = 



a' 



4a« 2b»kT' 



(22) 



T±€t 



* (t ± a) « "7= Je-^"dX. 



Observing that d logr — d log m — d log b and that d log a « d log b, 
we obtain from (11) and (20) the following expression for the suscepti- 
bility per unit mass: 

Nb*J , 4 e"'^'* + "'> 

(33) x-x-7 {4t>- 2rf + l - 



2of 



y/r * (r + a) ^ ^ {t -^ a) 
(2 r sinh 2aT + a cosh 2 a r). { 



The values of x divided by the constant N b* A f or various values 
of a and T, given in Table II, were calculated by Gans from formula 
(23). For a given value 6f the temperature,T, the quantity r is constant, 
from (22) ; and a is directly proportional to the field strength, from (20). 

Table II 
x+Nb«A 



a 


r-0 


r-H 


r-1 


r-2 


0.0 


-0.667 


-0.600 


0.000 


+2.00 


0.2 


-0.670 


-0.606 


-0.010 


+1.92 


0.4 


-0.681 


-0.614 


-0.040 


+1.69 


0.6 


-0.698 


-0.636 


-0.082 


+1.348 


0.8 


-0.719 


-0.660 


-0.136 


+1.093 


1.0 


-0.746 


-0.691 


-0.196 


+1.900 


1.6 


-0.8189 


-0.682 


-0.339 


+1.636 


2.0 


-0.8802 


-0.773 


-0.488 


+1.278 


3.0 


-0.9444 


-0.889 


-0.723 


-0.143 


4.0 


-0.9687 


-0.937 


-0.844 


-0.471 


6.0 


-0.9800 


-0.960 


-0.900 


-0.660 


10.0 


-0.9960 


-0.990 


-0.976 


-0.916 


00 

1 


-1.0000 


1.000 


-1.000 


-1.000 



The table shows that, for all values of r equal to unity or less, x is 
negative for all values of a, except that when r == 1 and a = 0, it 
vanishes; and that for r » 2, x niay be positive for values of a suf- 



PARA' AND DIAMAGNETISM: WILLS 77 

ficiently low, and negative for higher values of a; the susceptibility 
thus depending upon the field strength. 

A substance whose susceptibility, as regards sign, depends upon the 
field strength is called metamagnetic. Weber and Overbeck^ have 
observed the phenomenon of metamagnetism in copper-zinc aUo3rs; 
and Honda has observed it in the element Indium.* It is possible, 
however, that the observed phenomena might have been due to the 
presence of traces of iron in the specimens. 

Another interesting conclusion which may be drawn from the present 
theory is that, by suitable increase of temperature and field strength, 
all so-called paramagnetic bodies would become diamagnetic. 

The explanation of the curious results called for by the present 
theory of paramagnetism is to be found in the fact that the theory 
itself tacitly hypothecates two separable causes operative to produce 
magnetisation; one tending to produce diamagnetism, and the other 
paramagnetism. 

It is not difficult to see that the cause operating to produce dia- 
magnetism is the rotations, subject to thermal variation, of the 
magnetons about their equatorial axes of inertia; and that the cause 
tending to produce paramagnetism is the rotations, not subject to 
thermal variation, of the magnetons about their axes of symmetry. 

The relative strengths of these two operating causes depend, in 
accordance with the theory, upon the temperature and field strength; 
and, therefore, according to the values of these two quantities, the one 
cause or the other may predominate. 

In the second' of his papers published in 1916, entitled "Uber Para- 
magnetismus," Gans developed a theory of paramagnetism in which 
the molecular magnetic field is taken into account, this field having 
been ignored in his paper on dia-, para-, and metamagnetism just 
reviewed. 

It will be recalled that on the latter theory paramagnetism cannot 
exist by itself, but always occurs accompanied by diamagnetism, caused 
by the effects of thermal variations in the rotations of the magnetons 
about their equatorial axes of inertia; and that, with sufficiently high 
temperatures and external fields, the diamagnetism due to this cause 
may predominate over the paramagnetism due to the rotations with 
constant angular velocity of the magnetons about their axes of sym- 
metry. 

For temperatures which are attainable, however, in the case of almost 
all paramagnetic substances, the paramagnetic effect predominates 



1 K. Overbeck: Ann. d. Phys. 46. p. 677; 1915. 
s K. Honda: Ann. d. Phy». 32. p. 1043; 1910. 
» I.e. — p. 69, note 4. 



78 PARA'^ AND DIAMAGNETISM: WILLS 

strongly over the diamagnetic effect, which may consequently be ig- 
nored and each magneton considered to have a constant magnetic 
moment m due to its rotation with constant angular velocity about its 
axis of symmetry; it is assumed that this moment is the same for all 
magnetons. The magneton thus considered is the equivalent of the 
magnetic molecule of Lang^vin. 

With the assumptions relating to the magneton here made formula 
(85) y Sect. Ill, is applicable for the calculation of the magnet ic moment 

per unit mass. This formula gives the mean value, cos ^, of cos 9, 9 
being the angle between the direction of the axis of a magneton and the 
field K, whose relation to the external field H and the intensity of 
magnetisation, I, \b expressed by the equation: 

(24) ^"^+f'' 

The magnetic moment per unit mass is obtained by multplying 



cos ^ by the product of the number of magnetons per unit mass, N, 
and the constant magnetic moment, Mi of a magneton. We thus ob- 
tain, from the formula for cos $ in question, the following expression 
for the magnetic moment per unit mass: 



(25) M«Nmcos9 



' "^AdA I (cotha — ) ( — ^— ) dF, 



> O :I:(A-K) 



V^K*i ^,l^.Ks a K* 



where 






As regards the significance of the s3rmbols, it will be recalled that A 
is the scalar value of the molecular field, A^ the most probable value of 
A, F the scalar value of the resultant magnetic field, k Boltzmann's 
constant and T the absolute temperature. 

From the expression (25) for the magnetisation per unit mass, we 
now derive an expression for x, the susceptibility per unit mass. 
By definition: 



VdH/ VdK dH/ 



For isotropic sobetanoes, with which the theory is concerned, K and H 
will be oollinear, and from (24) we find: 



PARA' AND DIAMAGNETISM: WILLS 79 

dK , . 4ir dl 
dH ^ 3 dH 

and, ance for paramagnetic substances the second term on the right 
will be very small in comparison with unity, it may be neglected. We 
may therefore write: 

dM 



X=Lt K-« 



dK 



In the evaluation of the ri^t hand member of this expression the 
+ sign in the lower limit of the integral involving F in expression (25) 
for M is to be used, since in the limit E will be less than A. It is found 
after easy calculation that: 

(26) x= z^f'^/^J 1 L (a) + -ga L' (a) j e " *' A dA, 

where 

L(a) = cotha- - ; a^i^; 

a kT 

and L'(a) is the differential coefficient of L(a) with respect to a. 
For brevity we now write: 



(27) z - ^„ 


kT 

^"mA.' 


4Nm 


by (34) Sec. Ill: 






(28) 


^ 3*^^ Ms*' 





where No is Lioschmidt's number, M the molecular weight, p the 
density and s the smallest distance of approach between two magnetons. 
Upon introducing the abbreviations into (26) we finally obtain: 



(29) 



-«.]"{M^)+i^L',f)}e-d.. 



This formula implies a dependency of the susceptibility upon the 
temperature, since t is proportional to T; and also upon the density, 
since r and x© are each inversely proportional to the square root of the 
density. 

For liquids and solids, however, variations of the density with tem- 
perature may be disregarded. 



80 PARA' AND DIAMAGNETISM: WILLS 

For brevity kt: 

(80) ^ - e ; 

then, from (27) : 

(31) r - -| . 

Upon intiodueing the temperature function: 

we obtain from (29) : 

(83) --*(^) = *(r), 

a formula involving two disposable constants, Xo ^^^ ®- This formula 
implies that, with the exception of gases, all paramagnetic bodies obey 
a law of corresponding states. 

The value of the temperature function ^ (r) is now required. It is 
convenient to derive expressions for ^(r) for two cases; vis., when r is 
small, and when r is large. In the first case it is to be understood that 
r is not so small as to take the theory out of the equipartition range. 

Case 1. r small. 

For details of the calculation the reader may refer to the original 
paper. The result of the calculation is to show that: 

(84) *w=i-I^'+|(„)*+^V)»+^V)' ; 

the B's represent Bernoulli numbers a few of which are: 

_ 1 _ 1 _ 1 _ 1. 

' 6' 30' 42' 30 

Case 2. r large. 

The details of the calculation are also omitted in this case. It is 
found that: 



(36) 



^' 2 I 1! T 21 T» 3! T» / 



B Sf 

For very high temperatures, terms after thejfirst on the right of (35) 
may be neglected; it is then foimd from (33)^and (31) that: 

^ ^ X- ^ ^«T"3kT 

which is the Curie-^Lang^vin law for paramagnetism. 



PARA- AND DIAMA0NETJ8M: WILLS 



81 



This result was to be expected, sinoe at high temperautres the influ- 
ence of the molecular field upon the niagnetons is small in comparison 
with the disorganizing effects of thermal agitation. 

Experimental Test of Theory. 

The theory is compared by Gans with experimental determinations 
of the susceptibility by K. Onnes, Oosterhuis, Perrier and Honda. 

For Crystalline Gadolinium Sulphate (Gds(S04)a HsO), and for Ferric 
Ammonium Sulphate (FesS04(NH4)sS04+24HtO, the Curie-Langevin 
law is found to be well obeyed down to the respective temperatures 
T=20.1'*K, and T^U.T'K. On the present theory, for these two 
substances, and in fact for all for which xT is constant, the molecular 
field Aq is so small that G will also be small, so that T/G will still be a 
large number. The inference is that here the mutual action of the 
magnetons may be ignored. 

The substances listed in Table III, with the values assigned to the 
disposable constants Xo ^^^ ^ show, as regards their susceptibilities, 
agreement with the present theory which leaves little to be desired for 
temperatures as low as 14.7^K. 





Table III 






Substance 


Formula 


Xo 


e 


GryBtfiUine ferroua sulphate 

Ciystalline manganous sulphate. . 
Water-free ferric sulphate 


FeSOi .7H,0 
M11SO4 .4HtO 
Fe,(S04), 


2212X10-* 

4837X10-* 

302X10-* 


12.64 

9.90 

120.00 



Molecular constants, — The theory furnishes, with the aid of experi- 
mental results for the substances above considered, values for the fol- 
lowing constants: 

The nimiber of Weiss magnetons per molecule. 
The most probable value for the molecular field A. 
The smallest distance of approach, s, between two magnetons. 
For very high values of T we have, from (36) : 



(87) 



Nm* Vt 



3k 



XoQ. 



Now, since it has been assumed that each molecule contains only one of 
the magnetons of the present theory, /aNo will be equal to the magnetic 
moment per gram molecule. No being the Loschmidt number with the 
value 6.175X10*'; and No = MN where M is the molecular weight. 
Upon multiplying the preceding expression, (36), by MN; substituting: 
No for MN, and solving the resulting equation for mNo, we find: 



82 



PARA' AND DIAMAONETISM: WILLS 



(38) 



V! 



MNo-^7\/irkNoMxoe 



as the magnetic moment per gram molecule. 

If the molecule contain q magnetic atoms, then, in accordance with 
Weiss, mNo/q is an integer multiple, p, of 1123.5. Thus: 



(39) 



V 



1123.6 p -V-v^kNoMXoS^ q, (kNo- 8.316 X10»). 



We denote by p' the nearest whole number to the value for p calcu- 
lated from this equation. 

Weiss usually assumes q » 1 f or salts, such, for example, as Fei (S04)s, 
containing more than one metal atom. 

The most probable molecular field is calculated from the second of 
equations (27) as follows : 



(40) 



^kT kN^G 



kNoS 



fjLT mNo 1123.6pq 

The smallest possible distance of approach, s, between two magnetons 
is obtained from (28) : <^ 



(41) 



8« = 



16ir M*NoP 16ir 1123.6* qVP. 



9 MAJ 9 



N, 



Using the values of the constants Xo ^^^ ^ given in Table III, the 
results given in Table IV are obtained for Cr3r8talline Ferrous Sulphate, 
Crystalline Manganous Sulphate and Water-free Ferric Sulphate. 

Table IV 



Substance 


M 


p 


xoXlO* 


e 


P' 


P 

26 
29 
36 


AoXlO-* 
in Gauss 


sXlO* 
in cm. 


MnS04 .4H|0 

Fe(804).(q-1) 


278.0 
223.1 
390.9 


1.90 
2.11 
3.10 


2212 
4387 
302.0 


12.64 
9.90 
120. 


20.09 
29.13 
35.63 


0.3587 
0.2516 
2.494 


3.46 
5.25 
1.22 


Remarks — 








^ 











It will be noticed that the values for p' do not approximate very 
closely to integer niunbers; and the Weiss magneton theory here fails 
of any very substantial support. This circiunstance is, however, with- 
out influence upon the other molecular constants concerned. 

The molecular fields are seen to be quite large. Water of crystalli- 
zation appears to have the effect of decreasing the molecular field, 
owing probably to increase in the smallest possible distance of approach 
of neighboring magnetons. 



PARA' AND DJAMAONETISM: WILLS 83 

The Bmallest distance of approach, s, is of the order of one tenth the 
diameter of a molecule. This may be explained by supposing the 
magneton excentrically placed in the molecule. 

Although the present theory is in good agreement with experiment 
down to very low temperatures for the substances considered above it 
breaks down (at very low temperatures) for many others. Gans has 
therefore proposed a modification based upon a quantum hypothesis. 
This modification will be considered in Section VII, deaUng with 
quantum theories of magnetism. 

Theory of Honda and Okubo. 

In a paper entitled "On a Kinetic Theory of Magnetism in General'^ 
Honda and Okubo^ have attempted a modification of Langevin's 
theory for a paramagnetic gas, in which, effects due to the rotations 
of a magnetic molecule about axes perpendicular to the magnetic 
axis are taken into account. 

The vector magnetic moment of a molecule is considered as made up 
of two parts: an axial component in the direction of its axis of rotation^ 
and a transverse component perpendicular to this axis. 

In accordance with the argument advanced in the paper cited the 
axial components of the magnetic moments of the molecules of a body 
subject' to an external magnetic field would, due to the motions of the 
molecules induced by the field, give rise to paramagnetism; and the trans- 
verse components to diamagnetism. 

The theory has much in conmion, as regards its fundamental assump- 
tions, with Cans' theory of dia^, para-, and metamagnetism which has 
been reviewed in some detail above. 

The arguments of Honda and Okubo have been subjected to rather 
severe criticism by Weaver.* 

Theory of Oxley. 

In an extended series of very interesting papers entitled "On the 
Influence of Molecular Constitution and Temperature on Magnetic 
Susceptibility," A. E. Oxle}^^ has introduced a modification of Langevin's 
theory, in which the molecular field plays a leading role in diamagnetic 
substances, as well as in para,- and ferromagnetic substances. 

The theory of Oxley, bringing into prominence, as it does, the mole- 
cular field, is analogous in many respects to the theory of ferromagnetism 
developed by Weiss upon Langevin's theory of a paramagnetic gas as a 
basis, supplemented by the assumption of the existence within ferro- 
magnetic substances of enormous internal fields. 

1 Honda and Okubo: Phy. Rev. 13, p. 6; 1919. 

* W. Weaver: Phy. Rev. 16. p. 438; 1920. 

• A. E. Ozley. Roy. 8oc. Pha. Trana. 214. A. p. 109; 1913-14.— 215 A, p. 79; 1914-16. 
—220 A. p. 247; 1919-20. 



84 PARA' AND DJAMAGNETJSM: WILLS 

It therefore appeared appropriate to treat the work of Chdey and of 
Weiss together in a separate contribution. This has been done by Pro- 
fessor E. M. Terry in the part of this report dealing with ferromagnetism.^ 

Theory of Frivold. 

In a paper entitled "Zur Theorie des Ferro- und Paramagnetismus 
O. E. Frivold^ has developed a theory of ferro- and paramagnetism, 
consisting in a modification of Langevin's theory for a paramagnetic 
gas, in which the molecular magnetic field is taken into account. 

In this theory the elementary magnets or magnetons are identified 
with the atoms whose centers are supposed fixed at the comers of a 
cubic space lattice, and capable of rotation about their respective 
-centers. 

Statistical theory is applied to this system of magnetons, and results 
found from which the magnetisation curve may be obtained. Com- 
parison of this curve with the corresponding one which results from 
the Langevin theory furnishes a measure of the efifect of the mter-action 
of the magnetons, and permits the calculation of the magnetic molecular 
field. 

A more detailed account of this theory is given by Professor Terry 
in the section of this report referred to above. 

While other attempts toward the improvement of Langevin's equipar- 
tition theory of magnetism have been made, it is hoped that the considera- 
tion of those which have been presented here in more or less detail will 
serve to enable the reader to form a fair idea of the trend of attempted 
improvements on this justly celebrated theory. 

^ cf. p. 154 of this report. 

* O. E. Frivold. Ann. d. Phys. 65. p. 1 : 1921. cf. p. 132 of this report. 



PARA- AND DIAMAGNETISM: WILLS 85 

VII 
THEORIES OF PARAMAGNETISM BASED ON QUANTUM HYPOTHESES 

In 1911 Nemst^ showed, in contradiction to the laws of classical 
statistical mechanics, that the specific heats of polyatomic gases appear 
to decrease with decreasing temperature. This was confirmed later 
by the investigations of Scheel and Heuse,' and their results ascribed to 
the behavior of that portion of the specific heat which depends upon 
the rotation of the molecules. 

There then appeared a series of investigations having to do with the 
rotatory energy of molecules. Of these some were of a theoretical 
nature in which attempts were made at quantiticing the rotatory energy. 

Meanwhile the experimental investigations of Onnes, Oosterhuis, 
Perrier, du Bois, Honda and Owen on the variation with temperature 
of the susceptibility of paramagnetic substances gave results which 
were in opposition to equipartition theories of paramagnetism. The 
theory of magnetism was thus in a similar dilemma to that in which 
the theory of specific heats found itself. 

Modifications of existing theories of magnetism through the intro- 
duction of quantum hypotheses were, of course, in order. The earlier 
theorists in this field were faced with a fundamental difficulty, shared 
by some of those working at the improvement of the theory of specific 
heats, which had its origin in the attempted quantitization of the rotary 
energy of the molecules. 

Poincard at the Solvay Congress in 1911 called attention to the 
difficulty as follows: 

''Imagine an oscillator with three degrees of freedom, isotropic and 
capable of vibration in such manner that the periods of vibration are 
the same with respect to three axes. Thus, for motions parallel to the 
(x, y, z) axes, let the corresponding energies be respectively ohu, 0hv 
and 7hi;, where a, /3, y are all integers, h is Planck's constant, and u, the 
common frequency. Let the axes now be changed: with respect to the 
new axes the energies will be ahv, fi^hv, and 7'hu, where a', jS', / are 
integers. This is impossible." 

In reply Planck said: 

"An hypothesis of quanta for plural degrees of freedom has not yet 
been formulated, but I believe it to be nowise impossible of achieve- 
ment." 

In 1916 Planck,' through the publication of his paper on ''Die Ph3rsi- 
kalische Structur des Phasenraiunes," demonstrated the correctness of 
his view here expressed. 

> W. NenuBt: ZeiUdir. /. EUktroihem, 17, p. 015; 1911. 

• K. Scheel u. W. Reuse: Berl, Ber. p. 44; 1913; Ann, d. Phyw. 40, p. 473; 1913. 

> M. Planck: Ann. d. Phya. 50, p. 385; 1910. 



86 PARA' AND DJAMAGNETJSM: WILLS 

Prior to the publication of Planck's paper writers attempting to 
improve magnetic theories through the introduction of quanta hypoth- 
eses were forced to make such assiunptions as seemed plausible, yet not 
firmly based. 

We shall therefore pass over with but brief mention the earlier at- 
tempts at quantum theories of paramagnetism. 

Theory of Oosterhuis. 

Among the first in this field was Oosterhuis^ who proposed a modifi- 
cation of Langevin's equipartition formula for the susceptibility per 
unit mass: 

^"skT 

where N is Avogadros's nimiber, m the magnetic moment of a molecule, 
and k Boltxmann's constant. Here kT represents the mean energy 
per degree of freedom of a molecule, and Oosterhuis simply replaces 
this by the expression 

1 / hw hiK 

ekT _i 

representing the mean energy of rotation of the molecules for one degree 
of freedom on the quantum hypothesis of Einstein and Stem, which 
assumes all molecules to rotate, at a g^ven temperature, with the same 
angular velocity, v being the common frequency of rotation and h 
Planck's constant. 

Theory of Keesom. 

Keesom' does not assume with Oosterhuis that all molecules at a 
given temperature in a substance rotate with a conmion angular velocity, 
but considers the motions of molecular rotation to be resolved into a 
system of standing elastic waves, after the manner of Debye in his 
theory of specific heats. Owing to the discrete structure of matter, 
waves with a length shorter than a certain minimum determined by the 
structure are not possible of existence, and consequently the number of 
possible frequencies for the standing waves will be finite and all below 
a certain maximum, vm say. The magnetic molecule, as with Oosterhuis, 
is supposed to have a negUgible moment of inertia about its magnetic 
axis, while its other principal moments of inertia are supposed equal. 

The mean rotational energy corresponding to a single degree of free- 
dom is then f oimd to be 

I E. Oosterhuis: Phy. ZeOeehr. 14, p. 682; 1913. 
I W. H. Keeoom: Phy, ZeiUehr. IS, p. 8; 19U. 



PARA' AND DIAMAGNETISM: WILLS 87 



•m 



L f h«^ .1 



and this expression on Keesom's theory replaces kT in Langevin's 
formula for the susceptibility of paramagnetic substances. 

The theory of Oosterhius shows fairly good agreement with experi- 
ment, in fact about as good as that of Keesom, and as it is foimded upon 
far simpler assumptions is to be preferred. 

The Theory of Gans. 

In his paper ''Uber Paramagnetismus/'^ which appeared in 1916, 
and which has been reviewed in Section V as far as the part which 
deals with the equipartition portion of the theory is concerned, Gans 
proposes a quantum modification, in order to obtain a theory which 
will be applicable to all paramagnetic substances at very low tem- 
peratures. 

As was stated in Section V, his equipartition theory is in good agree- 
ment with experiments in the case of some substances down to very 
low temperatures. But susceptibility curves, (x-T), of observations on 
Uranium, Magnesium, Aluminium, Molybdenum, Mobium, Tantalum, 
and Wolfram all show a tendency at some point to become parallel to 
the T-axis; in fact this tendency in the case of some of these substances 
is evident at room temperatures; and in the case of Molybdenum and 
Wolfram at temperatures of 1200®C and 1100*'C, respectively. 

These experimental results cannot be accoimted for on his equipar- 
tition theory; and Gans was thus led to modify it through the intro- 
duction of a quantum hypothesis relating to the distribution of the 
rotatory energy of the magnetons. As in the case of his equipartition 
theory, Gans takes the molecular field into accoimt in his modification. 

It is important to remember that the quantum theory of Gans is 
only applicable for very low temperatures, where by the term low 
temperatures is meant temperatures at and below which the equiparti- 
tion theory is no longer valid; thus in the case of Molybdenum and 
Wolfram temperatm^s below llOO^C are considered as low tempera- 
tures. 

At very low temperatures it may safely be assumed that temperature 
agitation is so slight that the magnetons perform but small vibrations 
about their positions of equilibrium, which are determined for any 
magneton, in the absence of an external magnetic field, by the molecular 
field A at that magneton. In fact the vibration frequency, v, for the 

>l.c. 



88 PARA' AND DJAMAQNBTJSM: WILLS 

magneton, and the most probable value of v, say v^, are respectively 
given by: 

where J represents the moment of inertia of the magneton about any 
axis through its oentroid perpendicular to its magnetic axis. 

The quantum assumption now made is, that the energy distribution 
for the two degrees of freedom of the magneton about two perpendicular 
axes in its equatorial plane is the same as that which would obtain if 
each degree of freedom be treated as though it were that for a simple 
oscillator with this one degree of freedom. 

To give precision, then, to the fundamental assumptions now intro- 
duced, it is supposed that the typical magneton with moment m finds 
itself in a magnetic field F, and that the temperature is so low as to 
allow it to perform infinitely small vibrations about its equilibrium 
position determined by the direction of this field. 

Let 01 and 0s be the angular displacements of the magneton about 
two perpendicular axes, then the total energy, e, of the magneton will 
be g^ven by: 

(2) e =y («!«+«,«) + ^ W+«.«) = ^ (Ci«+C«), 

where Ci and C% are the maximum amplitudes of 0i and 0s, respectively. 
If j8 denote the angle which the magnetic axis of the magneton makes 
with the resultant field F in which it finds itself, then: 

cos^-1-- =1 ^— ; 

and the mean value in time of cos j8 will therefore be given by: 



^ 2 4 

and hence, with the aid of (2) : 



cos/J « 1 — 



2mF 



The spatial mean value of this expression over all the N^magnetons 
in a unit mass will be expressed by: 

where e is the mean energy of a magneton. 



PARA' AND DJAMAGNETISM: WILLS 89 

In accordance with the quantum hypothesis made by Gans: 

2hu 

(8) €= -h7 , 

kT 

e - 1 

the expression on the right being twice the mean energy assigned to 
each degree of freedom of the magneton, conforming with Planck's 
original theory of radiation which implies no zero-point energy. 
From the last two equations it follows that: 

hv 1 



(4) ^^ ^ "" ^ "■ i^ "E 



V 

kT 

e -1 



This expression corresponds on the equipartition theory to Formula 
(30), Sect. Ill viz. : 

kT / kT* 



cos P == ooth 



The equipartition theory is therefore modified in accordance with 
Gans's quantum hypothesis by replacing in (25), Sect. VI, 

_ mF . /mF, . hu 1 

^*^kT-VkT^yi-,-F-ir=i- 

e 

The subsequent development, taking account of the molecular field, 
is along lines closely analogous to those followed in the equipartition 
theory. For the details the reader may consult the original paper. 

The theory furnishes an expression for the susceptibility which 
contains three arbitrary constants: Xoi the susceptibility at absolute 
zero; $ {^hv^/k); and (^Mo/k). 

In the case of Platinum and Water-free Manganous Sulphate, with 
the values of the disposable constants given below, the theory is foimd 
to be in good agreement with experiment: 

Xo G $ 

Platinum 1.189xl0-« 2097.^ 60.0^ 

Water-free Manganous Sulphate 670. x lO"* 84.94® 23.5®. 

Molecular constants. — From these experimental results interesting 
information as to the following molecular constants may be obained: 

(a) The most probable vibration frequency, u^, of the magnetons 
in the molecular field. 

(b) The equatorial moment of inertia, J, of a magneton. 



90 PARA' AND DIAMAGNETJSM: WILLS 

The most probable vibration frequency, v^, for a magneton in the 
molecular field is given by: 

From the second of equations (1) we have for the equatorial moment 
of inertia of a magneton: 



4ir«wo^ 



where A^ may be calculated as in (40), Sect. VI. It is foimd that for 
Platinum A^b 1243X10*, and for Water-free Manganous Sulphate 
A^«2.292X10». 
Thus the following values are obtained : 

u^XlO"" JXIO** 

For Platinum 1.30 67.7 

For Water-free Manganese Sulphate . 0.483 12.4. 

Theory of von Weyssenhofif. 

Jan von Weyssenhoff,^ in a paper which appeared in 1916, appears to 
have been the first to evolve a quantum theory of paramagnetiBm in 
which the method operates explicitly with quanta from the beginning. 
This author avoids the difficulty brought forward by Poincare through 
the introduction of a simplified model to represent the structure of 
paramagnetic bodies. 

In this simplified model the magnetic molecules (magnetons) are sup- 
posed capable of rotation only about axes parallel to a given plane, 
(the x-y plane), and also perpendicular to their own magnetic axes. The 
angle between the z-axis and the magnetic axis of a magneton is denoted 
by $. The position of a magneton is then uniquely determined by some 
value of B between — r and r . It may reasonably be expected that such 
a model will show, as regards its magnetic properties, a behaviour 
similar to a more general one in which the magneton may turn freely 
about a fixed point. 

An external field of strength H is supposed to act in the direction of 
the z-axis. 

The potential energy, U, of a magneton with magnetic moment m 
is expressed by: 

(7) U= mH (1 - cos ^)« A« sin* ^ , where A« - 2mH; 

> J. yon Weyaienholf : Ann, d. Phya. 51, p. 285; 1916. 



PARA' AND DIAMAGNETJSM: WILLS 91 

and the kinetic energy, E, by: 

(8) E = ^J*« = ~^, where^ = M, 

and J 18 the moment of inertia about the fixed axis of the magneton. 

In the present theory the mutual magnetic inter-action of the mole- 
cules is not taken into account. Hence when A^O a magneton may 
turn freely about its fixed axis. For very large values of A all the 
axes of the magnetons will deviate but little from the direction of the 
external field H, and they will then behave in a manner quite similar to a 
system of Planck linear oscillators. For, the total energy of a magneton, 
6, which in the general case is given by: 

(9) e= 2 J^+A« 8in«^ = ^ + A« sin* | 
will in this case be expressed by: 

^^ 2 4 2J 4 

which is an expression identical in t3rpe with that for the energy of one of 
Planck's linear oscillators. 

It is now proposed to apply to this model the second quantum theory 
of Planck, or rather, that portion of it which is termed by him thermo- 
dynamic. 

To this end it is first necessary to consider the phase domain appro- 
priate to the model. This consists of a strip of the ^— ^ plane of breadth 
2ir, parallel to the ^-axis. Here 6 and ^, already defined above, 
may be designated respectively as the generalized coordinate and the 
generalised momentmn ^: 

(11) ^"^'^^2J^>=J^- 

The method of Planck now requires the calculation of the magnitude 
and form of the elementary domains in the O—^f plane of equal proba- 
bility. 

In accordance with Planck's ideas these elementary domains of equal 
probability must be bounded by curves e » const. For large values 
of A these curves must be ellipses, as is evident from equation (lO). 

The magnitude of each of the elementary domains must be the same 
and equal to Planck's constant, h, since for large values of A the mole- 
cules of the model are equivalent to a system of linear oscillators for 
which, as shown by Planck, the magnitude, h, of an elementary domain 
is independent of u, and hence of A. 



92 PARA' AND DIAMAGNETISM: WILLS 

The family of bounding curves, c » const., for the elementary dom- 
ains is given by equations of the type: 

(12) ^+A«8in«-«C^, 

where C is a constant for any given curve. 
The area bounded by any such curve will be given by: 



(13) 



/ ^ d ^=4 /\/2J(C?- A« 8in«| d 6, 



the limit of integration, g, depending upon the value of C. 
It is now required to find a series of values for C: 

such that the area of the elementary domain between the (n — 1) st 
curve and the n'th curve shall be equal to h for all values of n; or, what 
is the same thing, that the area enclosed by the n'th curve shall be 
equal to nh. 
We have, with the aid of (13) : 

(15) 4/v^ VCa*- A«sin«-da - nh, 

o ^ 

^f2sin-iC./A forC„ < A 
^ \ IT for C„ > A. 

The curves on the ^^ plane represented by equation (12) for 
different values of C are separated into two distinct classes; one class 
lying within the curve G, shown in Fig. 10, for which the external field 
H is such that C«A; and the other class l3ang without this curve. 
The values of C„ for the first class will all be less than A, while the 
values of Ca for the second class will all be greater than A. For the 
requirements of a theory of paramagnetism it will appear presently 
that only the second class need be considered. 

The case when the external field H is such that C^ »: A is interesting 
as representing the case in which the pendulous motion of a magnetic 
molecule is about to pass into rotary motion. The area of the curve 
G for this case is easily seen from (13) to be expressed by: 

(16) 4AV2J/co6- dd = 8A\/2J. 

o ^ 

If it were possible to express quite generally Cb as a function of n 
by means of (15), a formula for the mean energy of the magnetic 
molecules could be at once derived; also it would be possible to derive 
an expression for the orientation of the axes of the magnetic molecules 
as a fimction of the temperatm^ for a given field strength. Un- 



PARA- AND DIAMAONETISM: WILLS 



93^ 



fortunately, this general procedure is not possible, and the argument 

has to be restricted to special cases. It will appear, however, that one 

of these special cases is broad enough to furnish a basis for an explanation 

of paramagnetism. 
For the case in which the external field H is so large that the area 

of the curve given by (13) for 0^= A, viz., 8A\/2jr is much greater 

than h, all the elementary domains com- 
ing into consideration will lie within the 
curve G, and quite near the origin; and 
since d may now replace sin $, the 
bounding curves of the elementary do- 
I mains will become ellipses, one of which 
is shown by the dotted line in Fig. 10. 
This corresponds exactly to the case of 
Planck's linear oscillators. The attain- 
ment of this case, however, would require 
external fields far greater than can be ob- 
tained in practice. 
We now consider the special case in which the external field H is such 

that the area of the curve G, viz., 8A\/2J is far smaller than the 

quantum h. 
In this case: 




(17) 



H < 



y 



256/* J * 

As regards order of magnitude, m = 10""^°, J = 10"*° and h=6.55 
X 10"*'. Hence the order of magnitude of the right hand member of 
the inequality (17) will be 10*. This number represents a field con- 
siderably greater than any that can be obtained in practice and we 
may conclude that a theory of paramagnetism may be foimded upon 
this special case. 

Now if, for the moment, we consider the external field to be such 
that Ci = A, then the area of the curve G will be such that 8A\/2J = 
h; and it follows that the elementary domains coming into considera- 
tion in the present case, where 8ir\/2J is very smaU in comparison 
with h, will all lie outside the curve G. One of these is shown by the 
shaded area in Fig. 10. The upper limit of the integral in (15) will 
therefore be v, and the integral itself will therefore be a complete 
elliptic integral of Legendre. 

For the case of paramagnetism we have, therefore : 



(18) 



h = 4V2j| VC„* - A*sin»^dfl. 



94 PARA' AND DIAMAONETJSM: WILLS 

Writing: 

^ c.' 

the integral can be put in the fonn of a series: 

<19) n h - 4x>/2J C»|l - (i/ k««-(-J4)'-^ ... I 

From (19), 0^ has now to be found as a function of n and A. We pass 
over the details of the calculation which may be found on page 301 
of the paper under review. The calculation is simplified by the fact 
that A may be considered as a small qhantity. The result shows that: 

where 

4irv/2J 

n n 

Now let: 
N be the total number of magnetic molecules per imit mass; 
N <a^ the number of magnetic molecules per unit mass with energies 
between the limits specified by the boimdaries of the n'th elementaiy 
domain; 

e^ the mean value of the total energy for the N ta^ magnetic molecules. 
Also let: 



(22) *n » C. V2J y 1 - V sin« ^ , where k„ - p , 

2 ^« 

express the value of ^ for any point on the n'th boundary curve, ob- 
tained from (12). 
Then: 

(23) ^-^//(|j + A«Bm«^)d*d*, 

where the integration is over the nHh elementary domain. The result 
of the evaluation of the integral in (23) is to show that: 

kA A* 'T^J 1 1 

(24) ...ke(n-n)+f. + - + -^n^— ^-i). 

where 

h* 

(25) ke « -^^. 

The constant 8 has the dimensions of temperature. 



PARA' AND DIAMAGNETISM: WILLS 95 

From here on the calculation follows the lines laid down by Planck 
in the development of his second radiation formula in which the oscil- 
lators are supposed to absorb energy continuously and to emit it in 
quanta. 

The total energy, W, of the N magnetons considered is given by: 

(26) W = N 2 «„ €„, 

and this being supposed specified, the well known thermodynamic 
method of Planck^ leads to the law of distribution of energy: 

(27) Nwn = ae"^T « ofje , 

where ai is a constant which depends upon A and T but not upon n. 

Equation (26) gives the law of distribution of the magnetic molecules 
as regards their energy, that is, the number of molecules per unit mass 
with energies lying between the limits specified by the boundaries of 
the n'th elementary domain. 

The results so far found are capable of direct application in the 
theory of rotatory specific heats, and of paramagnetism. We pass over 
the part of the paper having to do with the theory of specific heats 
and consider now the application of the results found to a theory of 
paramagnetism. 

The potential energy of a magneton, from (7), is given by: 

(28) u = ~ (1 - cos e) = A' sin* ^. 

^ 2 

If X he the magnetic susceptibility per unit mass, then, as on Lan- 
gevin's theory: 

Nu 

(29) ^ " II ^^® ^' 



where cos is the spatial mean value of cos d, whose value on the present 
quantum theory will, of course, be different in general from that found 
on the equipartition theory of Langevin. 

Flt>m (28), if U denote the spatial mean value of U: 

2- 



(30) cos^ = 1 - -jU. 

A 

Now if Uq denote the mean potential energy of a magneton whose 
total mean energy, e^, is specified as being within the boundary limits of 
the n'th elementary domain (whose area on the ^ plane equals 
h), then: 

1 M. Planck: Vorlesungen Qber die Theorie der W&rmBirmhlanc — ^Dritter AbBchnitt. 



M PARA- AND DIAMAQNBTISM: WILLS 



U. -^/A»8m»^f.-f._.)d*. 



This equation, after the evaluatioii of the integral, with tlie aid of (22), 
and taking note of (20) and (21), gives: 

A* 2ii*JA* 
Therefore the mean values of cos 9 in the n domains will be given bjr: 



^i ,% 1 



(31) 



(co8tf).--^A'-— mH, (n-l). 



4**J »t , 1 1 



(COS*).- -rr A' (--—-) 
n n n— 1 



A* 1 mH 



8ken(n-l) 4ken(n-l) 

These equations, with the aid of the distribution function given by 
(27), enable us to derive directly the following expression for cos di 

• 1 -|(n«-n) 

1 — S e T 

mH 2 n (n-1) 



(32) cos e 



4k0 ; e^„, . „, 



From (29) and (32) we obtain the following expression for die mag- 
netic susceptibility per unit mass: 

_ 1 

?i??^-.T"~t n(n-l) 
h» 



(33) X - ^^^ir*J 



2e 
I 

where 

(34) T-^- 



- « (n> - o) 



T 32««JkT 
From (33) it follows that at suffidently high temperatures: 

'^ "2kT 



PARA^ AND DIAMAGNETISM: WILLS 97 

which agrees with the Langevin f onnula except that there here appears 
in the denominator a factor 2 instead of a 3, as in the Langevin formula. 
The model for the molecular structiu^ here adopted allows, however, 
but one degree of rotary freedom for the magnetic molecule and, if 
the Langevin calculation be carried out under the assumption of but 
one degree of freedom for the magnetic molecule, it turns out that the 
numerical factor in the denominator would be 2 instead of 3. There- 
fore the author introduces the factor 2/3 on the right of formula (33). 
The final formula for the magnetic susceptibility then becomes: 



A 1- 



M g_#(n«-n) 



(35) x^'4^^1 ^iil^)- 

1 

This formula gives for the mass susceptibility at absolute zero: 

16 Nm* 

(36) ^ '^ ^ "p" *" ^* 

A test of the theory is made through comparison of values of x> 
calculated (with appropriate values of the disposable constants Xo &^<1 
6) from the experimental values of x determined by Onnes and Ooster- 
huis for crystalline- and for water-free manganese sulphate, with re- 
sults given in Tables (V) and (VI) below. 

Theories Based on Planck's Method of Quantitization. 

Following the appearance in 1916 of Planck's paper^ on "Die physika- 
lishe Structur des Phasenraumes," which set forth the procedure to 
be followed in quantitizing the energy of an oscillator with plural de- 
grees of freedom, the time was ripe for fiuther improvements in the 
theories of rotatory specific heats and of paramagnetism. 

As mentioned above the point had previously been reached in the 
development of theories in both of these subjects where a method was 
required for the quantitization of the rotatory energy of a molecule, 
or magneton, with plural degrees of freedom of rotation. 

In theories of magnetism the magneton commonly hypothecated was 
supposed to have a constant magnetic moment due to its rotation 
about an axis of sjrmmetry, and to possess dynamic S3rmmetry about 
axes through its centroid perpendicular to the axis of symmetry; and, 
since the requirement of constancy for the magnetic moment of the 
magneton about this axis demands that its motion about it be inde- 
pendent of thermal agitation, only two degrees of freedom were assigned 
to it. 

> I.e., p. 85. 



98 PARA- AND DIAMAONETISM: WILLS 

The definite problem up for iolution before satiflfactoiy progresB 
could be made was: 

To quantitize properly the rotatory energy of a magneton with two 
degrees of freedom of rotation. 

In Planck's quantum theory of radiation the quantum difficulty of 
Poincare, stated above, does not arise, since the linear oscillator in- 
voked by Planck for the purpose of effecting interchange of energy of 
different frequencies in black body radiation has but a single 
degree of freedom. The probability elementary phase domains for a 
linear oscillator were shown by Planck to be the areas included between 
consecutive ellipses similar and similarly placed in the ^ plane, 
each area on his quantum hypothesis being equal to the imiversal 
constant h; ^ being the generalized coordinate of the oscillator rep- 
resenting its electric moment and ^ the corresponding generalized 
momentum, viz., the partial derivative of the kinetic energy of the 

oscillator with respect to the generalized velocity ^. 

Now from the viewpoint of Planck the quantum difficulty of Poincare 
may be stated as that of correctly delimiting the elementary proba- 
bility domain in the specific problem under consideration. If this 
delimitation be accomplished, the remaining difficulties are simply 
those of formal anal3rsi8. 

In cases where the statistical element or molecule has but a single 
degree of freedom the proper delimitation of the elementary proba- 
bility domains is generally a fairly simple matter, as in the case of 
Planck's linear oscillators, or again, in the case of the constrained 
motion of the magnetons in the model of molecular structure assumed 
by V. Weyssenhoff in his theory of paramagnetism. 

We shall now notice briefly some quantum theories of paramagnetism 
based on Planck's method of quantitization. 

Theory of Reiche. 

Fritz Reiche^ in 1917 published a very interesting paper entitled 
"Zur Quantentheorie des Paramagnetismus" in which he generalizes 
the assimiptions of v. Weyssenhoff as regards molecular structure by 
considering it to be such that each magnetic molecule (magneton with 
fixed magnetic moment) should be capable of free rotation about a fixed 
point. The rotation of the magneton about its magnetic axis (axis 
of synmietry) is supposed independent of thermal agitation and its 
moment of inertia about any equatorial axes through its centroid, 
denoted by J, is assumed to be the same for all such axes. ^^ 

From what has been said above it will be dear that the problem^bf 
Reiche differs essentially from that of v. Weyssenhoff only in that 

>F. Reiohe: Ann, d. Phy. 54, p. 401; 1917. 



PARA' AND DIAMAONETISM: WILLS 99 

part which has to do with the delimitation of the appropriate elementary 
phase domains. To go into the details of the anal3rsi8 whereby this is 
effected, following the method of Planck, would carry us beyond the 
scope of the present review and the reader who is interested is referred 
to the original paper; also to a paper by Adams. ^ 

The author finds an expression for the mean value of cos 6 for the 
magnetic molecules, where d is the angle between the magnetic axis 
of such a molecule and the direction of the external field H; and then 
substitutes this in the following expression giving the magnetic sus- 
ceptibility per unit mass: 

N/i 



X = ^ cos ^ , 



where N is the number of magnetic molecules per unit mass, /i is the 
magnetic moment of a molecule, and cos ^ is the mean value of cos 9. 
It is thus found that: 

(37) ^e-'+^^ •*"'■' 



V = Nm» j 4 3„..n(n«-l) . 



1 



where 

(38) <r - 



8ir*JkT 



The corresponding expression for x found by v. Weyssenhoff is 
given by (35), and it should be noticed that c in the theory of v. 
Weyssenhoff has a value equal to one fourth of that given by (38). 

For very low temperatures (o large) formula (37) gives: 

6 Nil* 
(39) x = 7-rr*'J; 



4 h* 



while (35) reduces to: 



(40) ^'J^^^- 

For high temperatures (a small) both (37) and (35) give: 

^'■3kT' 
the equipartition expression of Curie-Langevin. 

> E. P. Adams: BuU, Nai. Ru, Caun. I, 5, p. 301. 



100 PARA' AND DIAMAGNETISM: WILLS 

Other Theories. 

Sophie Rotssajn^ treated the same problem as that oonaidered by 
Reiche, using, however, a very di£ferent method of analyaia. The 
final formula found for the misceptibility is, as was to be expected, 
precisely the same as that arrived at by Reiche. 

The procedure followed by both Reiche and Rotszajn as regards 
quanta hypotheses presupposes the validity of what is commonly known 
as Planck's second theory of radiation, which assumes the absorption 
of energy by his linear oscillators to be continuous and the emission 
to be in quanta; and which predicts the existence of a zero-point energy. 
It will be recalled that on this theory the distribution of energy, for 
the stationary state, as regards frequency u, is, if c denote the mean 
energy of an oscillator of frequency v, given by: 



"fe*^) 



where h is Planck's and k Boltsmann's constant. 
In the first form of Planck's theory, eventually discarded by him: 

hi; 



kT 



e" - 1 

and thus does not predict the existence of a zero-point energy. 

A. Smekal,* in spite of the fact that the second fonn of Planck's 
theory is now conmionly preferred to the first, thought it worth while 
to develop a quantum theory of paramagnetism based on the assump- 
tions of the first form of the theory, using the same magneton model as 
that assumed by Reiche and Rotszajn. He was led to a fonnula for 
the susceptibility which shows by no means so good an agreement with 
the experimental facts as that found by them on the basis of the second 
form of Planck's theory. His result, then, adds another argument in 
favor of the second form of the theory and, therefore, for the existence 
of a zero-point energy. 

Comparison of Theories with Experiments. 

Of the various quantum theories which have been considered probably 
the most satisfactory is that of Reiche which, as far as the fundamental 
assumptions and the final results are concerned, is the same as that of 
Rotszajn. 

The theory proposed by v. Weyssenhoff is also satisfactory from the 
standpoint of its development from his fundamental assumptions; but 

1 8. Botssajn: Ann, d, Phu%, 57, p. 81; 1918. 
• A. Smekal: Ann, d. Phut. 57, p. 376; 1918. 



PARA- AND DIAMAGNETISM: WILLS 



101 



these are more artificial than those of Reiche and Rotszajn, including 
as they do the restriction of the movement of the magneton (apart 
from its rotation about its axis of symmetry) to motion in two dimensions. 

The theory of Gans, while based upon an incorrect quantmn hypoth- 
esis, takes account of the consequences of the presence of the ''mo- 
lecular field" which is ignored on other theories. Comparison of this 
theory with experiment has already been made (see p. 96 of M. S.) 

The theory of Oosterhuis may be taken as representative' of those 
theories, other than that of Gans, based upon quanta hypotheses which 
were developed before Planck in 1916 published his general method 
whereby quantitization may be effected in a statistical system whose 
elements have plural degrees of freedom. 



Remarks — 



Table V 



Wateb-fbee manganese sulphate — ^MnSOi 
Reiche ...J = 1.99X lO""**; 



k-41 



-21 



V. Wey. ... J = 4.44 X 10""; m = 4.35 X lO'^^ Xo = 6-577 X 10 



k-41 



-20. 



Oost. . . . J = .87 X 10""; /i = 1.80 X lO"""; Xo = 6-89 X 10 



k-6 



•TK 


xxl0*cal. 


xX10*cal. 


xXW 


xXlO«ca 




Reiche 


V. Wey. 


obs. 


Ost. 


14.4 


637.9 


646 


636 


628 


17.8 


614.9 


617 


627 


619 


20.1 


697.8 


694.3 


603 


603 


64.9 


316.1 


313.4 


314.5 


326.7 


77.4 


277.6 


276.1 


274.8 


284.0 


169.6 


142.7 


142.2 


144.2 


146.4 


293.9 


86.8 


88.9 


87.8 


86.3 



Table VI 
Cbtbtalline manganese sulphate — MnS04+4HsO 



Reiche ... J 
V. Wey.. . . J 
Oost. ... J 



3.14 X 10-~; 

1.1 X 10"~; M = 3.65 X 10"^'; ^o = 

1.09 X lO"**;/! = 1.69 X 10"' 



Xo » 



7.294 XIO"*. 
3.1000 X lO"*. 



VK 


xX10*cal. 


xXWcal. 


XX10« 


xXWcaL 




Reiche 


V. Wey. 


obs. 


Ost. 


HA 


1233 


1249 


1233 


1231 


17.8 


1014 


1019 


1021 


1015 


20.1 


905 


905.8 


914 


904 


64.9 


293.2 


290.3 


292 


291 


70.6 


270.6 


267.7 


270 


268 


77.4 


247.3 


244.1 


247 


245 


169.6 


114.6 


112.7 


111.5 


112.6 


288.7 


67.6 


66.5 


66.3 


66.3 



102 



PARA' AND DIAMAGNETISM: WILLS 



It must be remembered that none of the theories here mentioned 
takes cognisance of the mutual action of the molecules, except that 
of Gans, and in this respect is therefore deficient. 

Tables V to VIII enable one to judge as to bow far the theories 
are in accord with experiments. In this connection it should be noted 
that in each of them there are two disposable constants. 

Table VII 
Watbr-hubs rBRRic bitlphatb — FetCSOOi 



k-40 



-21 



Reiche ... J = 1.40 X 10"*; m « 3.42 X 10"^'; Xo = 286.4 X 10 



k-« 



TK 


xXlO*caL 


xX10*ob8. 


64.0 

70.5 

77.6 

169.6 

989.8 


177.6 

167.6 

156.7 

85.1 

53.3 


177.1 

167.3 

157.2 

85.6 

53.3 


Table VIII 
Cbtbtaiximb ncRBo sulphate: FeS04+7HsO 

Reiche ...J = 2.23 X 10 *;m « 2.94 X 10*";Xo = 3.365 X 10 *. 


T*K 


xXlO*cal. 


xX10*ob8. 


14.7 
20.3 
64.6 
77.3 
292.3 


760.5 
568.7 
189.8 
159.5 
42.4 


756 
571 
191 
160 
42.4 



PARA' AND DIAMAONETISM: WILLS 103 

vni 

DIAMAONETISM IN METALS 

DUE TO 

MOTIONS OF FREE ELECTRONS 

In accordance with views on the nature of electric conduction in 
metals brought forward by Lorentz, Drude and others, there are 
present in metals large nmnbers of free electrons which move about 
among the atoms in a manner similar to that of the molecules of a 
gas; and, moreover, the thermal properties of metals also lend support 
to the assumption that free electrons are present in them in large 
niunber. Although there are outstanding difficulties in the attempt to 
ascribe to free electrons many observed electric and thermal properties 
of metals there is yet strong evidence in favor of this assumption. 

If the free electrons are present and moving about in metals like 
the molecules of a gas, it is evident that in the presence of a magnetic 
field the free paths of the electrons wiU be curved, and with a curvature 
in such sens^ as to furnish diamagnetic quality to the metal. Super- 
imposed upon the diamagnetism due to the motion of the free electrons 
there will be, of course, the dia-, and perhaps the paramagnetism, of 
Langevin. 

Erwin Schrodinger^ in 1912 and H. A. Wilson* in 1920 have given 
theories of the diamagnetism in metals due to the motions of free 
electrons, arriving at quite similar conclusions by very different methods. 
For the purposes of the present review it wiU suffice to outline the 
argument presented by Schrodinger. 

Theory of Schrodinger. 

Stmcturdl Assumptions — ^The fundamental assumptions made as re- 
gards the structure of a metal are precisely those made by Lorentz in 
his theory of the motions of electrons in metals. 

Two distinct species of particles are supposed to be present in the 
metal: — 

(a) Electrons with mass m and charge e moving freely among the atoms. 

(b) The atoms of the metal, some of which carry a charge, while others 
do not. 

The electrons and the atoms are supposed to share in the thermal 
motion of the metal, the particles of each type in the case of thermal 
equilibrium having a mean kinetic energy equal to the mean kinetic 
energy of the motion of translation of a molecule of a gas at the same 
temperature as that of the metal. 

Due to the small mass of an electron as compared with that of an 
atom the velocities of the atoms are assumed negligible in comparison 
with those of the electrons. 

> E. SchrAdinger, Wien. Ber, 66, p. 1305; 1912. 

• H. A. Wilson: Roy, Soc. Proc, Land, 97, p. 321; 1020. 



104 



PARA- AND DIAMA0NBTI8M: WILLS 



The mutual action among the particles, io far as the electrons are 
concerned, is supposed to occur through collisions only and as if the 
colliding particles were perfectly smooth elastic spheres. 

Owing to their small size the collisions of the electrons among them- 
selves are ignored, and collisions only of electrons with atoms are 
considered. Accordingly the mean free paths of the electrons are not 
determined by their own number and size but by the number and size 
of the atoms. 

The Diamagnetism of Free EHectrons. 

When such a mediimi is subjected to the action of a magnetic field 
the free paths of the free electrons between collisions are no longer 
straight, but curved, due to the action of the field. The motion of 
the electrons along these curved free paths must act to produce dia- 
magnetism in the mediimi. 

It is now required to calculate the magnetic 
moment resulting; from the curvature of the 
free paths under the action of an external 
magnetic field. 

Referring to Fig. 11, dr is a small element of 
volume of the medium; (, 17, f the coordinates 
of an electron at a point Q within dr with re- 
spect to an origin 0, also within dr. P is a 
point on the z-axis at a distance r from 0, large 
in comparison with the dimensions of dr. The 
external magnetic field H is supposed in the 
direction of the z-axis. 

The magnetic force, say h, at P (0. 0. p) due to the typical electron 

at Q ({, 1?, f) moving with velocity v ({ 1?, f) is, from (11), Sect. I, with 
sufficient approximation expressed by: 

h - ^vx (r-B); 
cr* 

r is the position vector of P and s that of Q. The scalar z-component of 
this force is expressed by: 

h,- 4i (yf^ - ^)- 

cr* 

The expression in brackets is the z-component of twice the areal 
velocity of the typical electron with respect to and e/r* is constant 
for all the electrons in the volimie element. 

The mean value, hi, of hi, is to be found through summation of 
this expression for h| over all the electrons in dr, followed by integration 
over a sufficiently long time T, and division by T. The order of sum- 




Fio. 11 



PARA' AND DIAMAONETISM: WILLS 105 

mation and integration is, of course, indifferent and, sinoe the time 
integral of the areal velocity of the typical electron is equal to the area 
swept out by its radius vector, the time integral required is equal to 
the sum of the areas swept out in the time T on the x-y plane by the 
projections on this plane of the radii vectorii to all the electrons in 
the element dr. If F denote the sam of these areas, then: 

- 2e F 
cHT 

Calculation of F — ^The problem is thus reduced to the calculation of 
F. This requires a knowledge of the law of distribution of the veloci- 
ties of the electrons. 

Before the establishment of the external field Maxwell's law may 
plausibly be assumed; but with the field present the question arises as 
to whether this assiunption is still plausible. The following con- 
siderations show this to be the case. 

Following Boltzmann^ let us consider the case of a mixture of two 
gases, and let : 

i, ri, t he the coordinates of a molecule of the first gas; 

■ ■ 

(, 17, f be the component velocities of a molecule of the first gas; 

X, Y, Z be the component accelerations of a molecule of the first 
gas, due to the actions of external forces supposed dependent only upon 
the coordinates, (, 17, T; 

m be the mass of a molecule of the first gas; 

• ■ 

f (() Vf ti ii Vt D be the velocity distribution function for the first gas. 

Boltzmann showed that in the case of equilibrium (— » 0) : 

dt 

(2) f = foe-'*'°<^ + '*+^>, 

where fo and h are such functions of the coordinates (, 17, f that for all 
values of (, 17, f : 

• af • df • df df dt dt 

(3) f 7- + 1? - + f I- + X -' + Y?-' + Z^ « 0. 

dx dy dz af dri df 

Now it is assumed that this result may be applied to the present 
case, where the electrons play the role of the first gas and the atoms 
of the metal that of the second. 

The components of the force on an electron due to the external field 
H, say X, Y, Z, are given by: 

1 Boltsmann: Gas Theorie, I. pp. 08-134. 






106 PARA' AND DIAMAGNETISM: WILLS 

mc 

(4) Y- ~ (>Hi-fH.), 

mc 

Z-— (fHt-'nH,). 
mc 

Now it is noted that a violation of the Boltanann aflsmnptions is here 
met with, since X, Y, Z depend upon the velocities. Scrutiny of the 
Boltzmann proof shows, however, that it is still valid if it be amply 

assumed that X does not depend upon (, Y does not depend upon • 

and Z does not depend upon f . The above equations show that the 
X, Y, Z of the present problem are such as to satisfy these conditions. 
If now the value of f, from (2), be inserted in (3) we find, with the 
aid of (4), that the terms in X, Y, Z all vanish and hence that the 
equation 

dh • dh • dh. "df* • Bt^ ' d£k 
ox ay dz ox oy oz 

• • m 

must be satisfied identically by (, n, f . But this requires that fo and 
h shaU be independent of the coordinates and therefore constant. In 
this case the distribution function given by (2) is Maxwell's; and the 
conclusion is reached that the presence of a magnetic field does not 
alter the distribution of the free electron velocities in a metal. 

Proceeding with the calculation of F, let X^ be the mean free path 
(Tait's) of an electron moving with velocity v. The probability that 
an electron moving with the velocity v shall proceed without collision 
over a path with a length between a and a + da will be^ 

1 • 
(6) - e^da. 

It is here assumed that \y is independent of the velocity v and that 
for all electrons: 

1 



X= 



nirP 



where n is the number of atoms per imit voliune and 5 is the radius of 
an atom. 

The number of electrons per unit volume in dr with velocities between 
V and v+dv may be taken to be Vydv. Then the number of collisions 

t CV. JauiB— Kin. Th. of Gaw 3rd Ed., p. 256. 



PARA- AND DIAMAGNETISM: WILLS 107 

of such electrons per unit volume in time T will be 

-.vdv. 

The fraction of these collisions for which the velocities afterward 
have directions included within the solid angle da and, by virtue of 
(5), which are such that the colliding electrons after collision shall have 
free paths of lengths between a and a+da will be 

e ^ da. 

4ir X 

Therefore : 

vT -■ 

(6) 4;^*^ ^u^dvdcoda 

will be the number of collisions per unit voliune in time T of electrons 
with velocities between v and v+dv and for which: 

(1) the velocities after collision shall be directed within the solid 

angle do). 

(2) the free paths after collision shall have lengths between a and 

a+da. 
Such collisions are denoted as of class A. 

The volume element dr is now supposed subdivided into prismatic 
columns, dn, parallel to the z-axis with sectional dimensions small in 
comparison with those of dr, and also small in comparison with all 
ordinary free paths. The nimiber of collisions of class A within a prism 
of volume dn, by virtue of (6) will be expressed by: 

(7) vT - ? 

-— - e ^ Vy dv do) da dn. 
4irA* 

The areas described on the xy-plane by projections of the radii 
vectorii of the electrons concerned in these collisions, as they describe 
their free paths following the collisions, will all be appreciably the same. 

The process of the calculation of F now requires the finding of the 
sum of these areas for electrons of all classes of which class A is t3rpical, 
followed by integration over all prisms of which dn is t3rpical and, 
finally, by integration over all velocities of which v is typical. 

The area described on the xy-plane by the projection on this plane 
of the radius vector of a typical electron of class A is found as follow& 
Referring to Fig. 12, let A be the position with reference to the xy-plane 
of the electron at the time of a collision, B its position at the time of 
its next collision. The shaded area bounded by OA, OB and the arc 

AB is that required, the arc AB representing the free path of the electron. 



106 



PARA' AND DIAMAGNETI8M: WILLS 



From tbe equations of motaon of an eketton in a magnetie field, tbe 

path AB 18 easily shown to be an are of a drcle idiose length, b, is pven 
by: 

(8) b-aan^. 

and idioee radios, p, is given by: 

/AX mcv sin $ 

if 9 be the angle between the positive 
s-axiB (direction of H) and that of the 
axis of the cone corresponding to the 
soUd angle d«. 

If ^ be the angle between the tan- 
gent to the path at A and the radios vector OA, then: 




Fio. 12 



(10) 



Area OAB-Area OAB+Area CBA-Area CBA. 



In order to obtain F, the area given by (10) has now to be multiplied 
by the number of collisions pven by (7), and the appropriate integra* 
tions made. If we write dtf^sin B d$ d^, the following expression for 
F is thus obtained: 



+ -p^sm- + -/>bf d*, 
2 p 2 ' 

where b and p are given by (8) and (9) as functions of v and $, and OA 
depends only upon the position of the prism dll. 

All the integrations called for with the exception of that with respect 
to v are easily made and the expression for F reduces to: 



mcTdr 
3e 



f"vi — ,r„, -v«[dv. 



Vmc/ 



Now IV the number of electrons per unit volume with velodtieB 
between v and v+dv, is given by Maxwell's law: 

iv-av«e""'"^dv, 
where a and h are constants to be determined in tenns ci the total 



PARA' AND DIAMAGNETISM: WILLS 109 

« 

number n of electrons per unit volume, and the mean squares of their 

velocities v*, so that: 

4 ' 

^n(hm)^ 



V' 



hm = -=;. 
2v» 

The expression last given for F may now be put in the form: 

s 
4 mc n T dr (hm)* 

where 

OB - 

\mc/ 
J, « J e vMv - ^(hm)* . 



o 



It may be shown that with sufiScient approximation^ that : 



where 

(12) a 



^2mev/v* 



Inserting the expressions found for Ji and Jt in (11), the final expression 
for F is obtained: 

(13) F - - J — X»nTH (1 - 2a«)dr. 

omc 

The mean field strength, ht, at A, due to the motions of the electrons 
in dr, is then found with the aid of (1) and (12) to be given by: 

2 e* Hdr, 

h,= -- — Vn— -(l-2a«). 

3 mc* r* 

The form of this expression shows that the element of volume dr is 
magnetically equivalent to a doublet of magnetic moment 

1 e* 



3mc* 



X«nH(l-2a«)dr. 



I Cf. SchK^dinger, I.e., p. 1328 and p. 1315. 



no 



PAR\- AND DIAMA0NETI8M: WILLS 



It Kf be the magnetic Busoeptibility per unit volume it foUowB then 
that: 



(M) 



Discussion of Results. 



The fonnula (14), owing to the presence of the tenn in cf, shows that 
in general jc, depends upon the field strength, but it will appear presently 
that at ordinary temperatures a* will be negligibly small in comparison 
with unity so that with sufficient approximation we may take: 



(16) 



1 ^ X. 



Now the values of e and e/mc are well known, and nX and X may be 
estimated from electrical conductivity measurements and plausible 
assumptions concerning the true atomic volume. It is thus possible 
to calculate approximately the values of jk, for different metals. This 
has been done for Bi, Pb, Cu and Ag, chosen with particular reference 
to the wide range of electrical conductivity exhibited by this series of 
metals. The results are given in Table VIII together with the suscep- 
tibilities observed for these metals. The electrical conductivities a 
are expressed in C. G. S. electromagnetic units. The values given all 
refer to the temperature 18°C. 

Table VIII 



Metal 


aXW 


nXXlO-" 


nX10-» 


XX 10" 


-«iXlO»caL 


-KX10*ob8. 


Bi 


0.84 


0.046 


0.8 


5.54 


2.37 


13.7 


Pb 


4.84 


0.267 


4.8 


5.56 


13.8 


1.36 


Cu 


67.2 


3.174 


52.5 


6.04 


178. 


.076 


Ag 


61.4 


3.405 


53.4 


6.38 


202. 


2.10 



Comparison of the values calculated for jk,, the diamagnetic suscepti- 
bility due to the free electrons, with the experimental values, k, shows 
great differences to exist. It appears then that other sources of mag- 
netisation than that of the free electrons are contributory in an impor- 
tant way to the true magnetic susceptibility. The latter is probably due 
to the combined effect of: 

(a) The diamagnetism of Langevin; due to the induction effect during 
the establishment of the external field upon the bound circulating elec- 
trons within the atom. This effect is independent of the temperature. 



PARA' AND DIAMAGNETISM: WILLS 111 

(b) The paramagnetism of Langevin; due to the directive action 
of the external field upon the magnetically polarized atoms or mole- 
cules. This effect varies inversely with the absolute temperature. 

(c) The diamagnetism of Schrodinger; due to the curvature of the 
paths of the free electrons under the action of the external field. This 
effect depends upon the temperature in rather a complicated way. 

In the case of good conductors it may happen that the order of the 
effect (c) is the same as that of the effect (b) in strongly paramagnetic 
bodies. The dependency of effect (c) upon temperature, which appears 
through the factor nX' ,is, however, by no means so simple as that called 
for by Curie's law for paramagnetism which makes Uie susceptibility 
of paramagnetic bodies vary inversely as the absolute temperature. 
Therefore in all cases where effects (b) and (c) are in opposition and of 
the same order of magnitude any simple law of variation of « with 
temperature is not to be expected. Hereby is explained the failure 
of the experimental curves between susceptibility and temperature for 
metals obtained by Honda, and Owens, to exhibit any simple law of 
variation of susceptibility with temperature, and in particular why 
the susceptibilities of metals are so at variance with Curie's law. 

The connection between the magnetic susceptibility, jc^, and the 
electrical conductivity a, is obtained through comparison of formula 

(15) for Kf, with the following formula for the electrical conductivity 
obtained by Lorents on the same constitutive assumptions as those 
adopted by Schrddinger: 

(16) a-2Jl-^Xn — 

^ Sirmc* Vy* 

By division of (16) by (15) we find: 

(17) JL._2J«_i^. 

Under the same conditions X will not vary greatly from metal to metal, 
so that at the same temperature «, will vary, approximately, directly 
with a. 

The Dependence of the Susceptibility Kt upon the Field Strength. 
The formula found above (14) : 

is a closer approximation for «c, than (15). The approximation is close 
in either case only when cf is small in comparison with unity. Now a 
is directly proportional to the field strength, since, from (12) : 



112 PARA' AND DIAMAQNBTISM: WILLS 



V 



3 XeH 



and the quantity 

eH 

represents the radius of the free path of an electron moving with the 
velocity v^ perpendicular to the field. If, then, a* is to be small in 

comparison with unity, the mean free path X must be small in comparison 
with this radius. 

Calculation shows that with an external magnetic field of 5X10^ 
gauss, the largest practically obtainable, the order of magnitude of 
2af at 18^C is 10"^. Therefore any effect due to the variation of the 
external field could hardly be detected. But calculation also shows 
that at very low temperatures a marked decrease of susceptibility with 
increasing field strength should be detected. 

Note. — ^Professor Langevin has recently informed the writer of an 
interesting result found by N. Bohr in his dissertation. In accordance 
with the argument advanced by him it appears that the free electrons 
in a metal, subject to Maxwell's Law of distribution for a simple gas, 
should, on the whole, contribute nothing to its diamagnetic quality, 
owing to the behaviour of the electrons at the boundary whereby they 
produce an equal and opposite effect to that of the electrons in the 
interior. Unfortunately this information reached the writer too late 
to allow of the incorporation in the report of an outline of Bohr's argu- 
ment. 



FBRR0MAGNETI8M— INTRINSIC FIELDS: TERRY 115 

THEORIES OF FERROMAGNETISM— INTRINSIC FIELDS 

Bt Earlb M. Tbbrt 
AflBociate Professor of Physics, Uniyersity of Wisconsin 

HISTORICAL STATEMENT 

In the early attempts to ac count for the phenomena of f erromagne- 
tism, two rival theories were offered, — one by Poisson and the other 
by Weber. Both regarded magnetism as a molecular property, but 
they differed essentially in this, that while Poisson assumed the mole- 
cules possess magnetic properties only when the substance is magnetized^ 
Weber considered that they have constant magnetic moments, and that 
gross magnetism depends upon alignment. The fact that ferromag- 
netic bodies all show saturation was taken as evidence in favor of 
Weber's theory, for it is difficult to see why on the Poisson theory 
magnetism should not be increased without limit. Again, the effecto 
of vibrations in augmenting susceptibility were readily accounted for^ 
because of the greater freedom thus given to the molecules to fall in 
line with the magnetizing force. The experiment of Beetz^ in which 
he found that iron deposited electroUtically in a magnetic field pos- 
sesses strong magnetic properties, furnished further evidence in favor 
of the Weber theory. 

The fact that ferromagnetic bodies do not show saturation for very 
weak fields and the phenomenon of hysteresis are evidences that there 
must be some form of constraint acting upon the molecular magnets. 
Weber' assumed a restoring force equivalent to that of a constant mag- 
netic field acting upon each molecular magnet in the direction of its 
axis in the unmagnetized state. This assimiption, however, offers no 
explanation of residual magnetism or of the other phenomena of hys- 
teresis. In attempting to correct this defect in the Weber theory. Max- 
well suggested a further assumption based upon the analogy of magne- 
tization to elastic fatigue. He supposed that after a molecule has been 
deflected from its original position by a magnetizing force, it returns only 
partly if the deflection exceeds a certain value. While explaining reten- 
tivity and some of the other phenomena of hysteresis, this theory fails 
to account for certain facts observed in repeated magnetization. It 
was suggested by Wiedemann and others that the deflection of the 
Weber magnets might be opposed by a frictional resistance which not 
only opposes alignment, but also holds the molecules in their deflected 
positions after magnetization. If, however, the molecules were held 
by friction until the appUed force is large enough to start them, the- 

iPogo. Ann, 140, 1860, p. 107. 

s Pogg- Ann, 88, 1852, p. 167, cf. p. 9 of this report. 



114 FBRROMAONBTISM'-INTBINSIC FIELDS: TBRRY 

flUBoeptibility for very weak fields would be zero, whereas it has ini- 
tially a small constant value. 

THE THEORY OF EWING 

In contrast to the arbitrary constraints mentioned above, Bwing 
proposed the theory that the molecular magnets are entirely free to 
turn about their centers, and that the only constraints acting are the 
fields due to neighboring magnets. This idea he developed in great 
detail and, in fact, laid the foundation for much of the work which has 
since been carried out. From a mathematical consideration of the 
simple case of a 2 magnet group acted upon by an external field, he 
obtained a ciu^e in which the three stages of magnetization are clearly 
indicated and by an experimental study of a model in which 130 snudl 
pivoted magnets were used, he obtained magnetization and hysteresis 
curves which approximated the observed curves for ferromagnetic 
bodies with surprising accuracy. He gave a theoretical treatment of 
the case of a ferromagnetic body made up of rhombic crystals with 
molecular magnets placed at the comers of their space lattices, where 
the crystals are placed with all possible orientations. By a statistical 
method, which has been the basis for the subsequent work of Langevin, 
Weiss, Honda, and others, he showed that the percentage retentivity 
should be .8927, and deduced a number of other important results. 

THE WEISS MOLECULAR FIELD HYPOTHESIS 
Statement of Langevin's Theory. 

It was pointed out in a preceding part of this report that Langevin^ 
by an application of the method of statistical dynamics, has arrived at 
an expression for the intensity of magnetization of a paramagnetic gas 
in terms of the electron theory. For this purpose he supposed that the 
state of magnetization depends upon two factors only; first, the external 
field which tends to produce alignment in a given direction, and second 
the thennal agitation, which acts for disorganization. By an applica- 
tion of the Maxwell-Boltzmann distribution law, in which the number 
of magnetic molecular axes pointing in a given direction corresponds 
to the density of a gas, and the angle with the external field to height, 
he arrived at the foUowing expression for the intensity of magnetiza- 
tion of a paramagnetic gas at a temperature T under the influence of 
a field H : 

(1) — = coth a — , where 

' <^mo a 

*^^ ^m H 

■ Langevin, Ann, de Chem, et de Phya., Ser. S, 5, 1905, p. 70. cf. p. 56 of this report. 



FSRR0MA0NETI8M— INTRINSIC FIELDS: TERRY 



115 



In these equations, 

c^ = Magnetic moment per gram molecule; 

(Tm = Magnetic moment per gram molecule at saturation; 

H = External field ; 

T = Absolute temperature ; 

RT = Twice the kinetic energy for one degree of freedom of a 

molecule; 
R =Gas constant for a perfect gas referred to the molecular 

mass (R=83. 15X10^ ergs per degree). 

Langevin's equation, plotted as C in Fig. 1, gives the percentage 
saturation for a paramagnetic gas at any temperature as a function of 




a 

Fig. 1 

the apphed field. In weak fields, the intensity, crm, is proportional to 
the field, but the slope becomes less with increasing field and finally 
approaches assymptotically to the saturation value crmo. By a simple 
calculation he showed, for the case of oxygen, that a field of 100,000 
gauss would be necessary, at ordinary temperatures, to produce an 
appreciable departure from the linear law. 

Langevin showed also that the well known experimental law of 
Curie, i. e. the inverse proportionaUty of the susceptibility to the 
absolute temperature for paramagnetic substances follows directly from 
bis formula. Developing the right hand member of equation (1) in 
a series, there results: 



(3) 



^m a 



— =:.-;::: aM 



'm. 



3 90 45.42 



aH 



116 PBRROMAONBTISM—INTRINSIC FIELDS: TBRBY 

Taldog, as an approximation which holds over the range of fidds 
experimentany realixable, the first term only in this devdopment, 
we have: 

^^ ^m^ 3 SRT' 

Letting X«, » - » the molecular susceptibility, there results: 

C^ is called the "molecular" constant of Curie, i. e. the proportion- 
ality factor when the susceptibility is referred to the gram molecule. 
Curie's law, as expressed by equation (5) holds for a large number cS 
paramagnetic substances over wide ranges of temperature. Assuming 
it to hold at absolute sero, ^^m^, the saturation value of the intensity 
may be determined for a substance by measuring its susceptibility at 
A known temperature T. This is the hypothesis which has been made 
by Weiss in his theory of the ''Magneton'' to be discussed later. 

The Molecular Field. 

By postulating a "Molecular Field," Weiss^ has extended the ideas 
of Langevin to the phenomena of ferromagnetism. In this he was 
guided by the method which Van der Waals used to develop a kinetic 
theory of liquids by extending the ideas which Bernoulli had applied 
to a perfect gas. Just as in the case of a gas, to account for the transition 
to the liquid state, there must be added to the external pressure an 
internal one due to the mutual attractions between the molecules, so 
in the case of a ferromagnetic substance, as it is cooled in a magnetic 
field from a temperature which has rendered it paramagnetic, the 
transition to the ferromagnetic state is explained by assuming that, due 
to the overlapping of the fields of the individual molecules, there comes 
into existence an internal or molecular field, which added to the external 
field, accounts for the very large intensity characteristic of this state. 

Weiss assumes that the overlapping of the fields of the molecules 
existing in a given region is equivalent to a imif orm field proportional 
to the intensity of magnetization and directed parallel to it. Thus: 

H„-NI, 

! de Phya., 4th Series, Vol. 6, 1907, p. 061. Arch, des Scieneea Phyt. et Nat., 
1.31. 1911, p. 401. 



I 



FERROMAONETISM—INTRINSIC FIELDS: TERRY 117 

where Hm is the molecular field, I the intensity of magnetization and 
N, a constant characteristic of the substance. The molecules con- 
tributing to this internal field are contained in a definite sphere of 
action. He assumes, moreover, that the forces due to the magnetic 
fields are the only ones which act upon the molecules of a ferromagnetic 
substance and, except for them, the molecules are as free to rotate as 
in the case of a perfect gas. 

Spontaneous Magnetization. 

Weiss further supposes that it is not necessary for an external field 
to be acting in order that the individual parts of a body may be mag- 
netized. On the contrary, he assumes that throughout the body the 
molecular field alone maintains the intensity of magnetization of the 
elementary units of volume at a magnitude very near the saturation 
value for the particular temperature at which the body exists in the 
same way that a fluid, by virtue of the internal attractive forces, main- 
tains its liquid state in the absence of an external pressure. The 
volumes throughout which this spontaneous magnetization exists in an 
uninterrupted manner are very small, limited perhaps to the individual 
crystals. In a finite body with resultant intensity zero, the directions 
of magnetization of the individual elements are distributed entirely at 
random, and the fimction of the external field, in giving a resultant 
intensity to the body, is to produce an alignment of the individual 
group intensities, but not to change their magnitudes. In other words, 
if one could examine with sufficient minuteness, he would find an im- 
magnetized body to possess the same intensity as one grossly magnetized 
in the most powerful fields available. 

The magnitude of the spontaneous intensity of magnetization may 
be obtained in the following manner. Equation (1) gives the value of 
the intensity of magnetization at any temperature T in terms of the 
saturation value by means of the auxiliary variable a. It is then 
merely necessary to replace H in Equation (2) by H„ = NI and sub- 
stitute in Equation (1). This may be effected most easily by means 
of a graphical elimination of a between the two equations. In equation 
(6), I is defined as the magnetic moment per unit volume, while a„ is 
the magnetic moment per gram molecule. It is therefore necessary to 

replace I by its value ^ , where D is the density of the substance. 

m 

Accordingly: 

^""o ND 
(7) a'^ ^ p rp Xcr^, and 

m K 1 

^ ^ «^«. <^«*„ N D ^ * 



118 FBRROMAGNBTISM— INTRINSIC FIELDS: TERRY 

The last equation g^ives the straight line of Fig. 1, which intersects 
the former curve in two points. It is easy to show that the intersection 
at corresponds to a state of unstable equilibrium and that the one 
at A is the one concerned. Since the parameter a contains T, the 
spontaneous magnetization as a function of the absolute temperature 
may be readily deduced. 

The Magnitude of the Molecular Field. 

Anticipating for the moment what is to be shown presently, it may 
be stated that the molecular field is very large compared to fields 
available in the laboratory. However, in the temperature interval 
between the ferro- and paramagnetic states, there is a small region in 
which the molecular field is of the same order as realizable fields, and 
by measurements made in this transition region the constant N of 
equation (6) may be determined; and from it the value of H„, the 
molecular field may be computed. 

For this region equation (2) may be written: 

,^, <^m, (He+NI) <^m, (H.+ — O 

(9) a^ rY— = ^-7^—' 

RT 

where He is the external field. At the transformation temperature 0, 

(10) L«_ _ »' and a - ^=^^^^^ 
^ ' "m, 3 IWm 

Eliminating a from these two equations, 

»»« N D. 



(11) 9 = 



3Rm 



(12) 



Combining (11) and (9) and reducing, there results: 

T - ^ He m . 



^ (T^ND 



<^m, 



Letting x^ ^ ^^ where x., is the molecular susceptibility, there 

He 

results: 

An 



(13) (T - «) X« 



ND 



FERROMAGNETISM— INTRINSIC FIELDS: TERRY 119 

This is a modified form of Curie's Law and states that the suscepti- 
bility is inversely proportional to the excess of the temperature above 
the transformation point. This law has been found to hold for this 
region with very good accuracy and from it the value of N has been 
deduced. 

The following values have thus been obtained: 

Substance N Hn 

Iron 3,850 6,6d0,000 

Nickel 12.700 6.360.000 

Magnetite 33.200 14.300.000 

Cobalt 6,180 8.870,000 

Experimental Evidence Regarding the Ebdstence of the Molecular Field. 

1. The law of Corresponding States and the Variation of {he Saturatum 
Intensity with Temperature. — ^As noted above, an unmagnetized body 
consists of minute crystals all magnetized to the saturation value for 
that temperature but having their magnetic axes distributed at randonicic 
The process of magnetization consists in lining them up, and if we could, 
apply an external field sufficient to produce gross saturation, we shou^e^ 
be able to measure the molecular intensity, since it would then be the J 
same as the gross saturation. Further, a study of the variation of tl^. 
saturation intensity with temperature should furnish a direct test ojf 
the concept of the molecular field as given in equations (1 ) and (6) 
This test may be facilitated by a general equation applicable to all 
substances analogous to that for corresponding states in the kinetic 
theory of gases. Such an equation may be obtained in the following 
manner. 

The slope of the straight line of Fig. 1, is proportional to the tempera- 
ture T. Accordingly, by giving successive values to T and determining 
the intersections with the curve C, the law of variation of intensity 
with temperature may be derived. The limiting case is that in which 
the straight line coincides with the tangent to the curve at the origin, 
and corresponds to the temperature 6 at which spontaneous ferro- 
magnetism disappears. This transformation temperature may be ex- 
pressed in terms of the constants of the medium by noting that at $, 
equation (1) may be written with sufficient accuracy by using only the 
first term of the development of equation (3); that is: 

(14) ^ = ?• 

Also equation (8) becomes: 



120 



FBRROMAGNBTISM'-INTRINSIC FIELDS: TERRY 



(16) 



(15) by (14) there reeuks: 



e 



3mR ' 



(16) by (8), and mmplifymg, one obtains: 



(17) 



1* « ? ??L 



This equation, together with equation (1) g;ives the complete law of 
the thermal variation of spontaneous ferromagnetism, and when ex- 

pressed in terms of the variables — and -^, is the same for all substances 

6 ^mo 



(T, 




dm. 




The full line of Fig. 2, taken from the original paper of Weiss shows 
the calculated curve, and the crosses, the values obtained for magnetite. 
The work was carried out in a field of 8300 gauss although previous 
experiments had shown that this material is practically saturated in a 
field of 550 gauss. The agreement is satisfactory except in the low 



FBRBOMAONBTISM'-INTRINSIC FIELDS: TERRY 121 

temperature region where marked departm^ occur. For pyrrhotite 
and the alloy Fes Ni the agreement is more satisfactory than for 
magnetite; but for iron, nickel and cobalt, the agreement is less satis- 
factory in that larger systematic departures are found. 

2. The Dependence of Specific Heat upon Oie Molecular Fidd. — If 
ferromagnetic substances are the seats of molecular fields of the mag- 
nitudes stated above, a considerable amount of energy must be supplied 
as the temperature is raised from absolute zero to the transformation 
point in order to break up the alignment of the molecular magnets 
within the crystals. We should expect, then, that in this region, the 
specific heat would be greater than it would be, if by some means the 
substance could be deprived of its magnetic properties. This effect 
should show itself as an additive term to the true specific heat of a 
corresponding fictitious substance having no magnetic properties. The 
amount of this additional heat may be computed from the theory of 
the molecular field in the following manner. 

The mutual potential energy E of a group of magnets of moment m is 

(18) E = - S M H cos a, 

where H is the resultant field due to the group at the point where an 
individual magnet is located, and a is the angle between H and this 
magnet. When the summation is extended to all the magnets con- 
tained in a centimeter cube, there results: 

(19) E = ^IH„=-^NP, 

where I is the magnetic moment per unit volume, H^y the molecular 
field, and N the constant of equation (6). The negative sign indicates 
that it is necessary to supply heat to demagnetize the substance. The 
intensity decreases in a continuous manner from absolute zero to the 
temperature at which the disappearance of ferromagnetism occurs. 
Accordingly, the amount of additional heat that must be supplied in 
raising a ferromagnetic body from a temperature at which the inten- 
sity is I, to the Curie point 6, is 

(20) Q-^^P-i5=I 
^^^ '^ 2JD* 2JD' 

where J is the mechanical equivalent of heat and D, the density. The 
mean specific heat accordingly, is: 

dq IN dp 1 do* 

^ ^ "^ dT 2J D dT 2J dT 



122 PERROMAGNETISM--INTRINSIC FIELDS: TERRY 

where a is the magnetic moment per imit mass. This quantity is small 
at low temperatures, but increases as the temperature is raised and 
disappears abruptly at 6. At this point, it has the nature, not of a 
latent heat of allotropic transformation, but of a discontinuity in the 
true specific heat. 

The magnitude of this discontinuity has been calculated by H.^A. 
Lorentz.^ Developing in a series the theoretical law of the variation 
of magnetization at saturation as a function of the temperature, he 
found at 6: 

do* 5 (T * 

where <r^ is the saturation value of c. 
Taking into account the relations: 

(23) ^=CND, and 



(24) a, , 



3R^C 

m 



where C is the Curie constant referred to unit mass, R the gas constant 
for a single molecule, and m the molecular mass, he obtained: 

On substitution of the nimierical values for R and J there results: 

(26) aC„ - — . 

m 

Weiss^ and his co-workers have tested this theory in a series of ex- 
periments extending over a period of several years. In the early work, 
equation (21) was used as the form in which to make the test and the 
results seemed to check the theory within the limits of accuracy of the 
experiment. In the later work, however, where greater care was 
taken, the check is less satisfactory. The results in which the Lorents 
equation (26) was used are summed up in the following table: 

> H. A. Lorents, Reoue ScierUifique, 1912, 50 aiin6e« p. 1. 

* Weiaa and Beok, Joum, de Phyt., 4th Series, 7, 1908, p. 249. A. Dumas, Zurich 
Thesis, 1909. Weiss. Piccard and Carrasd, Arth. des Sei. Phyt. et Nat,, 42, 1916, p. 379, 
%l80 43, 1917, p. 113, and 43, 1917, p. 199. 



FERROMAGNETISM— INTRINSIC FIELDS: TERRY 



123 



Table II 



Substance 



Nickel 

Magnetite (Artificial) 
Magnetite (Natural) . 

Iron (Pure) 

Iron (Swedish) 



ACm observed 



0285 

0790 
0736 

120 
124 



ACm computed 



.0282 
.0644 

.089 



Corresponding 
mag. molecule 



Ni, 
H(Fe,04) 

Fe 



3. Magnetic Properties of CrysUda and the Hysteresis Curve. Weiss^ 
and his group have examined a number of iron minerals and found that 
some of them possess marked magneto-Ksrystalline properties. One of 
the best examples is Pyrrhotite, a sulphide of iron. These crystals 
are usually in the form of hexagonal plates bounded at their edges by 
faces of a hexagonal prism and are deeply striated parallel to the base. 
If one examines their magnetic properties in planes parallel to the base, 
he finds that there is one direction in which they are very easily magne- 
tized, while at right angles to this direction it is difficult to produce 
saturation. Further, in the direction normal to the base, saturation 
is still more difficult. Weiss found that the fields necessary for satura- 
tion in these three directions are 15, 7300, and 150,000 gauss respec- 
tively. After an extended examination, he concluded that the complex 
crystalline structure consists of a juxtaposition of elementary crystals 
of which the magnetic planes are parallel, that each crystal possesses 
a direction of easy and difficult magnetization at right angles to each 
other, and that the crystals are grouped in the magnetic plane with 
their axes making angles of 60^ with each other. 

The direction of easy magnetization is further characterized by the 
fact that the intensity of magnetization can be changed in sense but 
not in magnitude. For example, if one acts upon a crystal in this 
direction with a large field, and then gradually reduces it, carrying 
it through zero to negative values, he finds that the intensity remains 
constant down to a value of — 15 gauss when it suddenly reverses and 
takes a negative value of equal magnitude. In other words the h3rste- 
resis curve is a rectangle with lines parallel to the H axis extending 
out from the upper right and lower left hand comers. The magnetic 
properties of Hematite have been studied by Kunz' who found it to 
be similar to pyrrhotite in that it possesses directions of easy and 
difficult magnetization, though the effect is less marked, and that the 
coercive field is somewhat larger. It is ferromagnetic in some direc- 
tions and paramagnetic in others. 



> Weifls, Joum. de Phya., 3rd Series, 8, 1899, p. 642. 
* Kuns, Areft. det Sci„ 23, 1907. 



124 



FERROMAGNBTISM^INTRINSIC FIELDS: TERRY 



Weiss has attempted to explain h3rsteresis phenomena in pure metals 
by assuming that their individual crystals possess properties similar to 
pyrrhotite; that is, directions of easy and difficult magnetization, and 
that each crystal is magnetized by its own intrinsic molecular field to 
the saturation value for its existing temperature. In gross matter, in 
the immagnetized state, the directions of easy magnetization will be 
arranged entirely at random. The process of magnetization in a given 
direction consists then simply in reversing the direction of magnetiza- 
tion of those elementary crystals whose intensities have components 
opposite to the external field. For a given cr3n3tal, this reversal occurs 
when the component of the external field in the direction of its axis 
equals He, the coercive field. 

The form of the hysteresis ciu've to be expected on the basis of this 




Fio. 8 



assumption may be obtained in the following way. Let M be the mag- 
netic moment of each crystal, and N the nimiber of crystals per unit 
volume. Since the distribution of directions is entirely at random, the 
end points of the vectors M will be uniformly distributed over the sur- 
face of a imit sphere. Let the external field H act in the direction OX 
of Fig. 3, and let H^ be the magnitude of the coercive field. Elemen- 



FERROMAQNETISM— INTRINSIC FIELDS: TERRY 125 

taiy magnets having axes l3ring within the cone of semi angle ^ vertioal 
to the one indicated in the figure will be swung into this cone. The 
angle ^ is determined by the expression H cos^—Hg. 

The number of vectors ending in the zone determined by d ^ is given 
by: 

/«^x 2irr*sin*d*^^ N . 

(27) 4irr' ^ ="^«^ * ^ *• 

The magnetic moment of these magnets in the direction OX is: 

N 

(28) M,=Mcos0 — sin0d0. 

The moment due to aU the magnets reversed into the cone is 



f*MN . 



(29) M,= / — — sin cos d 

Jo 2 

MN Im . ,^ 

= — — sm*0=--sm*0. 
4 4 

The total magnetic moment due to the magnets in the cone is then: 

(30) ^''-;^''^-k['-{fJ\ 

In this discussion it has been assumed that the elementary crystals 
can be magnetized, only in the direction of easy magnetization, while 
if they resemble pyrrhotite, they are paramagnetic at right angles to 
this direction. Weiss has computed the appropriate correction and 
has matched a set of h3rsteresi8 curves taken from the results of Ewing 
as shown in Fig. 4. 

The Elementary Magnets of the Ferromagnetic Substances. 

In his original study of a paramagnetic gas, Langevin expressed the 
intensity of magnetization as the magnetic moment per unit volume 
instead of per gram molecule as Weiss has done in his later work. For 
this quantity he used the letter I and his equation was: 

(31) r- * cosh a — , where 

(32) a«^; 
^ ^ RT' 



126 



FBRROMAONBTISM-'INTRINSIC FIELDS: TERRY 




Feq.4 



FEKROMAQNETISM'-INTRINSIC FIELDS: TERRY 127 

fi is the magnetic moment for a single molecule and the other quan- 
tities have the same meaning as before. In the neighborhood of the 
transformation temperature 0, these equations become: 

la mH 

(33) r"~3» *^^ * ~RT' ''^spectively. 

Putting H = N I and eliminating a there results: 

3R 



(34) M = 



NC 



an expression by means of which ^ may be determined for those sub- 
stances for which the quantities 6, N, and Im have been determined. 
This calculation has been carried out by Kunz.^ R is the gas constant 
for a single molecule and may be obtained from the equation: 

(36) p=NiRT, 

where Ni is the nimiber of molecules per cc. Substituting the values 
for the quantities involved, at one atmosphere and Oo C, 

p = 1.01 X 10* dynes per cm^ 
T =273 
andNi=:2.7 XW\ 
there results: R =1.36Xl(ri«. 

Taking, for iron, Im = 1950, the value obtained by extrapolating the 
results of Curie, for N = 3860, the value given by Weiss and Beck,* 
and substituting in equation (34) there results: 

(36) M = 4.445 X l(r*® absolute electromagnetic units. 

As a check on the reasonableness of this result, a calculation of the 
mass of the hydrogen atom was carried out using it and the known 
density and molecular weight for hydrogen. Let No be the number of 
molecular magnets per cc. in iron at absolute zero. Then: 

(37) NoM=1960, 

whence No = — = ^^ = 4.386 X 10". 

° u 4.445 Xl(r*» "^^^^ 



» Kuns, Phy; Rev., 30, No. 3, March, 1910. 

* Weias and Beck, Joum. de Phy:, 7, 1008, p. 249. 



128 



FBRBOMAGNBTISM— INTRINSIC FIELDS: TBRBY 



If it 18 assumed that each molecule possesses one elementary magnet 
of moment m> then this is also the number of molecules per cc. If m 
is the mass of one molecule of iron, and D its density, then: 

Nom = D=7.36, 



(38) 



whence m 



7.36 



4.386X10" 



1.792X10-** grams. 



If Mh is the mass of the hydrogen molecule and it is assumed that 
the molecule of iron has two atoms, then: 



(39) 



Ml 



1.792X10-" 
111.8 



1.603X10-** grams. 



A recent value of this quantity deduced by Rutherford from radio- 
active phenomena is: 

Mh = 1.61 X 10^* grams. 

If the corresponding calculations are carried out for nickel and cobalt 
using the best available data the results given in the following table 
are obtained. 



Substance 



Fc 

Ni, 
Co 



Im 



1950 

570 

1435 



766 

376 

1075 



N 



3,850 

12.700 

6,180 



NI-HM 



6,540,000 
6,350,000 
8.870,000 



mX10»* 



4.445 

3.65 

6.21 



M,xia-«* 



1.603 
1.603 
1.61 



N 



2 

6 

4 



It is to be noted that, in order that the computed mass of the hydrogen 
atom should have the values given, it is necessary to assume that the 
molecule of nickel has six atoms and that of cobalt four. 

The Nature of the Molecular Field. 

The hypothesis of the molecular field as introduced by Weiss is a 
useful concept in the theory of ferromagnetism and has served a num- 
ber of useful purposes. For example, by adding to the external field 
the molecular field it is possible to explain many of the complicated 
phenomena of ferromagnetism by the laws of paramagnetism. It 
gives a theoretical law for the variation of the saturation value of the 
intensity with temperature through the ferromagnetic range, and leads 
to a law for the intensity variation with temperature above the magnetic 
transformation point. By assuming for the molecular field different 



FERBOMAGNETISM—INTRINSIC FIELDS: TERRY 129 

values in different directions it is possible to account for many of the 
complicated phenomena of crystals, and by taking into account the 
energy associated with the molecular field an explanation for the dis- 
continuity in the specific heat at the transformation point is obtained. 
The phenomena of the molecular field, moreover, are' not confined to 
ferromagnetic substances, as there are many instances of its evidence 
in the case of paramagnetic and diamagnetic substances as well. One 
may cite, for example, the work of Kammerliegh Onnes and Perrier^ on 
the magnetic properties of mixtures of liquid oxygen and nitrogen; that 
of KammerUegh Onnes and Oosterhuis' on paramagnetic substances at 
low temperatures; Weiss and Foex on paramagnetism of crystalline 
substances, Foex on concentrated sahne substances, and Oxley on dia- 
magnetic substances, to be discussed later. It is true that in many 
instances, the check is only qualitative and indicates that the theory 
in its simple form is insufficient, and that the molecular field, instead of 
being proportional to the intensity of magnetization should be repre- 
sented by a more comphcated function such as : 

(40) H„ = NiI+N3P+ 



While the hypothesis has thus been useful in explaining many observed 
facts and directing new lines of investigation one is at once struck by 
its enormous magnitude and is led to inquire by what means fields of 
such intensities may be produced. For this purpose one might proceed 
in the manner employed by H. A. Lorentz for dielectrics and describe a 
sphere within which there exists a single molecule while on the outside 
all the other molecules, in their mean effect, play the role of a homo- 
geneous substance. He would then find for the coefficient N of equa- 

4 
tion (6) the value ~ r which falls far short of that experimentally deter- 

mined on the basis of the theory. 

Again, using known data, one might compute on the basis of the 
inverse square law the necessary distance from a molecular magnet at 
which the observed molecular field would occur and see whether it 
leads to values consistent with the known densities of packing of mole- 
cules. Take, for example, the molecule of iron which contains eleven 
magnetons, and suppose that it has a length equal to .2X10~^ cms. the 
diameter of the atom, and let m be the strength of its magnetic pole! 
Then since the magnetic moment of the magneton is 16.4X10"^, there 
results: 

mX.2XlO-' = llXl6.4XlO-«, 
or m=.9XlO-". 

> Kam. Onnes and Perrier, ArM. de Chemie, 4th Series, 26, Sept., 1913. 
* Kam. Onnes and Oosterhuis, Comm. Leiden No. 129, p. 132. 



130 FERBOMAGNBTISM—INTRINSIC FIELDS: TBRRY 

The distance from such a pole at which there would exist a field of 
strength equal to that of the molecular field, 7X10*, is given by: 

m .9X10-" 

---^^ 7X10», 

r* r* 

whence r« 3.6X10"" ; 

a value much less than the measured distances between molecules. It 
thus appears that fields of the required magnitude can be obtained 
neither by superposition of the effects of neighboring molecular magnets 
using the known average values of the intensity of magnetization, nor 
by assuming sufiScient closeness of packing of the individual molecules. 
On the other hand one might enquire whether it is possible to obtain 
such fields by allowing electrons to rotate with very high velocities in 
closed orbits about the positive nucleus. For example, suppose an 
electron having a charge of 1.6 XlO"*^ to rotate in a circular orbit of 
diameter .2X10"^ with a frequency of 10** equal to that of ultra-violet 
light. The magnetic moment of such a circuit would be: 

Moment = 1.6X 10-««X 10"XirX lO"" 

= 5X10-«, 

which is equivalent roughly to three magnetons. The strength of the 
field at the center of the trajectory is: 

„ 2-ir-610-» 10"- ,^ 

^ TIF^ '''' 

which is too small by a factor of 100. 

It thus appears that the molecular field can have neither a magnetic 
nor an electromagnetic origin and must therefore be of a nature differ- 
ent from the ordinary magnetic fields with which we are familiar. 
Weiss* has suggested that the molecular field may be of the same nature 
as the ''magnetizing action of contact" observed by Maurain' and others 
in their study of the magnetic properties of electrolytic iron deposited 
in a magnetic field. This work will be reviewed briefly. Maurain 
showed that iron deposited in a field of a few gauss is much more strongly 
magnetized than that deposited without the field and afterwards sub- 
jected to one; also that when the field in which the deposition occurs ex- 

> AnnaUa de Phy:, 1, 1914, p. 148. 

* Maurain, Joum, de Phyt,, 4th Series, 1, 1002, pp. 00 and 151. 



FERROMAGNBTISM--INTRINSIC FIELDS: TERRY 131 

ceeds ten or twelve gauss the iron is saturated. This iron maintains its 
saturation value, practically independent of the field, but suddenly 
reverses under a coercive force of 20 gauss and the hysteresis curve is 
practically a rectangle similar to that of P3n:rhotite in its direction of 
easy magnetization. The saturation values were rather low, however, 
being only about 840. 

Eaufmann and Meyer^ who repeated the work of Maurain, have con- 
firmed his results regarding the shape of the hysteresis curve and the 
value of intensity for weak fields, but by using stronger fields they 
obtained intensities as large as 1100. Schield^ has also studied iron 
thus deposited and found an intensity of 080. All of these intensities 
are considerably less than those for ordinary iron, i. e., 1700, and one is 
led to suspect that their peculiarities may be due to the presence of a 
hydride of iron. This seems all the more probable from the fact that 
many of these peculiarities disappear with time but may be partially 
restored by making the specimen the cathode of an electrolytic cell. 
Nevertheless the results obtained have an important bearing on the 
molecular field theory. 

Maurain also found that the first layers of the deposit are different 
from the later ones in that they are but weakly magnetic. In fact it 
was only after the deposit had reached a thickness of 80mm that its 
magnetic moment increased in proportion to its thickness. It thus is 
evident that there are two fields acting on the molecules at the instant 
of deposition; first the external field and second, that due to the polarity 
of the iron already deposited. This latter he called the ''magnetic 
field of contact." He tried opposing these two by reversing the external 
field after a suitable thickness of deposit had been obtained. It was 
found that as long as the external field did not exceed the coercive field, 
usually about 20 gauss, the magnetic moment increased in the direction 
of the original field for some time in proportion to the thickness and that 
it was only after the thickness of the new deposit had become com- 
parable to that of the original one that the magnetic moment became 
zero and finally reversed. The reversal of the polarity of the original 
deposit took place slowly and could be observed with the magnetometer. 

He next studied the dependence of the field of contact upon distance 
by depositing upon the magnetized cathode suitable layers of neutral 
metals such as gold, silver, and copper of varying thickness and again 
depositing iron. With the external field reversed, he found that with 
a thickness of 38mm of the neutral metal the new layers of iron behaved 
in the same way as those deposited on an unmagnetized cathode. In 
other words at this distance the contact field just neutralizes the exter- 

iPhy8. Zeitachr,, 22, 1911, p. 513. 

> Shield, Ann, d. Phyt., 4th Series. 25, 1908, p. 612. 



132 PERROMAGNETISM—INTRINSIC FIELDS: TERRY 

nal field. On the other hand, for very thin layers of neutral metal the 
contact field is very large compared to the external field. The char- 
acter of this 'Afield of contact" is as yet unexplained, but it seems 
probable that it is of the same nature as the ''molecular field," and in 
view of the work of Oxley on diamagnetic substances is worthy of fur- 
ther study. 

Theory of Frivold, 

As was pointed out above, Weiss concluded that the large molecular 
fields required by this theory of ferromagnetism could not be of purely 
magnetic origin but must arise from other magnetic forces. In order 
to determine to what extent the fields of the individual atomic magnets 
can ac<;ount for the molecular field of Weiss, an extended calculation 
has bei3n carried out by Frivold.^ For this purpose he assimies that 
the equilibrium of the elementary magnets is determined not only by 
the external field and the thermal agitation, as in the Langevin theory, 
but alfo by the overlapping of fields of the elementary magnets and 
treats the problem from the standpoint of statistical mechanics. The 
calculation is carried out for 2 cases: the unidimensional and the vol- 
ume distribution. 

1. The Unidimensional Problem: Elementary magnets of number N 
are considered to form a long chain and to be free to turn about their 
midpoints. They are in statistical equilibrium under the influence of 
their undirected temperature motions, the external fields, and their own 
mutual field. Let the origin of co-ordinates be located at the middle 
of the chain, and let $ and be the usual polar co-ordinates, and let 
the axis of co-ordinates and the external field coincide with the direction 
of the chain. If the magnetic moment of an individual magnet is fi, 
and if their instantaneous positions are given by ^i^i, dt^^ .... 
^N^N> statistical mechanics gives, for the mean magnetic moment of the 
chain at a temperature T in the direction of the chain, the following 
expression : 



-*/• • ■ h 



V 



(1) Mt=A / . . . / Ai2cos ^^e " dOidOt . . . d^N. 



Here U designates the potential energy of the chain, k the Boltzmann 
constant (k== 1.35X10'^* ergs), and dn the solid angle formed by the 
element of surface sin Odd d^ on a unit sphere. The integration is 
to be taken through the 2N variables, $i ^i, ^s ^s, . . . . ^n ^- 
The constant A is determined from the following consideration : The 
probability of a given condition characterized by the fact that the di- 

> Frivold. Ann. der Phynk, 65. p. 1. 1021. 



FERROMAGNETISM^INTRINSIC FIELDS: TERRY 133 

rection of the axes of the elenentary magnets lie within the solid angles 
dQi, dQs> . . • . dils is 

Ae ""dQidQi . . . . dON- 

Integration of this expression, when the co-ordinates and ^ run 
throughout the values 1 to N, gives for the probabiUty the value imity. 
Therefore: 

kt 
(2) A I ... I e dQidQs . . . dn^^l, 



/•••/' 



and 

. . . / /* 2 cos ^N e ^T d Qj d Qj . , . d 12n 

W iviT= J '' \ _^ 

/ . . . / e kT d 12i d Q, . . . d Qn 

In order to carry out the integrations in equation (3), it is necessary 
first to determine the potential energy U. This consists of two parts, 
that due to the mutual potential energy of the elementary magnets, and 
that due to their positions in the external magnetic field. Calling 
these Ui and Uj, respectively, we have: 

U = Ui+U, 

(4) • =^,^ 2'[(m„ m„+x)-3(m,„?)(m„+i, ?) j-2 (m,,, ff). 

The expression in brackets is an approximation found to be accurate 
within 6 per cent. 

The mean magnetic moment of an elementary magnet, which con- 
sists of such a chain may then be evaluated. Introducing the following 
abbreviations: 

2 fk=0, where fk = f m^, mk+ij-sf m^, ^Vm^+i, ^^ 



(6) 



Sgk=^, where gk=f— , gj; 

1 ^ mH 

-,;ikT = P, and ^ = q; 



,j,_dQ, do, dQN . 

^^~ 4ir ■ 4ir • • • • 4ir ' 



184 



PBRSOMAQNBTISM—INTRINSIC FIELDS: TERRY 



equation (3) becomes: 



(6) 



Mt- 



77—7 



e«*+^dS 



Letting now the integral in the denominator be designated by J, 
there results: 



(7) 



Mt d 
M dq 



J may be expanded in a power series in p^, that is, in pt wers of 



M» , 



a»kT 



and integrated term by term. Thus: 



(8) 



J- 1 .... ye^(l+p*+^p**«+ . . .)dS. 



The approximation, given by the series development, is closer the 
higher the temperature T. To evaluate A it is necessary to determine 
the following mean values : 



W 



D^J* .... Je^dS; 
Di-J .... Je^^p^dS; 



When these integrations have been carried out, neglecting the quad- 
ratic and higher powers in (8), there results for the mean magnetic 
moment of an elementary magnet in terms of its absolute value, the 
following expression: 



= (cothq-^)r] 



(10) ^=lcothq-- jl 1+4' , ^ ^ 
^ Nm \ q/L a»kT dq 



(cothq — )+ . 



PBRSOMAQNETISM—INTRINSIC FIELDS: TERRY 



135 



If the reciprocal action of one magnet on another is not taken into 
account, the second term in the square bracket of (10) is zero, and there 
results the well known Langevin expression. The extent of the devia- 
tions from the Langevin expression, brought about by the introduction 
of the mutual actions, may be seen by substitution of numerical values 
in (10). If we assume that the chain consists of iron atoms, which, 
according to Weiss, possess 11 mangetons, each having a moment equal 
to 16X10-" C. G. S. units, and for "a" assume the value 2XlO-» cm., 
then at a temperature of 300° absolute, since k«1.35XlO-^*i there 
results: 



a'kT 



3.7X10-^ . 



In figure (5), curve (1) represents the original Langevin function, 
while curve (2) is 

-p-lcothq ). 

dq\ q/ 

This last expression for the values assumed above has a maximum of 
^ at a field strength of 10* gauss. The mean magnetic moment, when 



M 


• 


9 ^^^ 


....^r—— 


1 


^ 


■ — 





HxlO 



*6 



Fig. 5 



the mutual actions are taken into account is represented by curve (3). 
Since the mf^-TiTniim value of the departure from the Langevin curve is 
of the order of 10"*, the effect is here greatly exaggerated, and it must 
be concluded that at this temperature the effect of the mutual actions 
is quite negligible, and a magnetic body consisting of a chain of magnets 
with the values given above shows only paramagnetic properties. 

It is to be noted that in the above development, the integration of 
the equation (8) was carried out for the first two terms. If the quadratic 



136 



FBRROMAGNBTISM— INTRINSIC FIELDS: TERRY 



term Ls included, the calculation is much more complicated, but the 
result shows that for external fields of 50,000 gauss, the magnetic mo- 
ment of the chain is a linear function of H. 

At low temperatures, on the other hand, the conclusions are quite 
different. For small values of T, a number of simplifications in equa- 
tion (8) may be introduced and the equation corresponding to (10) is 
found to be: 



(11) 



Ml 



Nm d q 



log J 



-^[ 



1+2 -, + 



•]■ 



where n — — --; 



m*2 



+ 



H 



a'kT 2kT 



The results for four values of T are shown in figure (6). Smoe the 
approximations do not hold for extremely weak fields, the curves are 



Tg.oi 




Fig. 6 



shown dotted in this r^on. The chain shows, therefore, at low tem- 
peratures, properties characteristic of ferromagnetic substances, but it 
goes over into the paramagnetic state for temperatures of a few degrees 
absolute. 



PBRROMAONBTISM— INTRINSIC FIELDS: TERRY 137 

2. The Three Dimensional Problem. The calculation for the case of 
the space lattice is carried out in a manner similar to that of the uni- 
dimensional problem. The elementary magnets are r^arded as lo- 
cated at the comers of a cubical space lattice and turn about their mid- 
points. The expression for J in equation (8) is evaluated as before but 
is complicated by the fact that double summations must be made. If, 
as a first approximation, the expression corresponding to D and Di of 
equation (0) are evaluated, there results the well-known Langevin 
equation: 

M ^ 1 

(12) rr~=icothq 

N/i q 

If, however, the quadratic term of equation (8) is included, an expres- 
sion, in which the mutual actions appear, is obtained. Two cases have 
been studied — the ordinary cubical space lattice and the centered cubic. 
For the former, Frivold obtains: 



+ 



VkT/l 4 \a»kT/ 16^ • • • -J' 



and for the latter: 



<»' i^.-^^?[{'-?tfx)"--} 



+ 



/mHV 3^/_i^Y^lU 1 

VkT/ 4 Va'kT/ 15/"^ . . . • J- 



A comparison of these equations shows that the numerical factors in 
the two cases are of the same order and, consequently, the difference in 
the arrangement of the atoms plays no important role. Accordingly, 
in the following discussion only the former case will be considered. If 
the mutual action is left out of account, equation (13) gives for the 
case, in which the external field is relatively small, the well-known Lange- 
vin equation for small fields: 

M,_l/iH 



138 FBRROMAQNBTISM—JNTRINSJC FIELDS: TBRRY 

and for the initial permeability: 

M, 1 M* N 



(16) 



H 3kT 



If, however, the mutual action is taken into account, equation (16) 
becomes: 

(17) M,_l^ r 6^/^« 1 

^^^^ H 3kT^L 4\a>kT/^- • • • J i 



which indicates that the effect of the mutual action is to reduce 
permeability. 

A study of equation (13) shows that for external fields of such magni- 
tude that q' comes into consideration, a temperature transformaticm 
point is evidenced. For example, the magnetization curve (13) lies 
above, coincides with, or is below the curve of equation (17), according 
as the sign of the coeflScient 



VkT/ 



is positive, zero, or negative, or, in other words, are equal as T is greater 
than, equal to, or less than 



Brk V9M> 



a'k I' 2.66X16 

The magnitude of these departures is, however, very small, as may 
be seen by the substitution of the generally accepted numerical values 
for iron. For example, putting /i = 1.76X10-*® C. G. 8. units, a « 2.86 
X10-« cms., and T=390** absolute, 



\a? k T/ 



^10-^ 



From this it must be concluded that at ordinary temperatures, the 
influence of the mutual actions upon the magnetization curve for the 
case of the hypothetical magnetic substance we have here considered, 
is negligible. The reason for this is the small value for the moment 
of the elementary magnet. It is of interest to consider the case in 
which the atoms contain, in addition to the elementary magnets, dec- 



PBRROMAGNBTJSM^INTRINSIC FIELDS: TERRY 139 

trie dipoleSi the electrie moments of which are of the order of those 
found for SOs e. g. 10~^*; that is, 100 times larger than the magnetic 
moments for iron atoms. The external magnetic field then starts the 
lining up process, whereby the internal electric and magnetic fields 
are brought into play. Frivold has carried through the calculation in 
this case, also, and obtained the following expression: 

ri8A MTlft.Hr/ 6.27/ M.' Y, \ 



^'^jifUiry-hh--] 



where the subscripts m and e refer to magnetic and electric moments, 
respectively. Much larger departiu'es from the case in which mutual 
actions are neglected are thus obtained, for here 



a»kT 

Unfortunately, the integral of equation (8), upon which the entire 
treatment rests, is developed in powers of p ^, i. e. of 



a»kT 



and the series is convergent only when this expression is less than unity. 
The question as to whether ferromagnetism can thus be explained by 
the assumption of electrical dipoles, is still left open, but interesting 
possibilities are here suggested. 

Theory of Gans. 

A theory of ferromagnetism has been developed by Gans in which 
he has attempted to take into account the effect of molecular structure 
upon magnetic properties, and to make more precise the ideas concern- 
ing the nature of the molecular field than was done by Weiss. He sup- 
poses that an elementary magnet or "Magneton" is an electrified body 
of revolution rotating rapidly about its axis of figure. An elementary 
complex consists of a group of such magnetons, distributed according 
to the laws of probability throughout a space which has the form of an 
ellipsoid, the three axes of which are unequal. The magnetons are free 
to move about within the complex in the samemanner as the molecules 
of a gas. A ferromagnetic crystal is built up of such complexes placed 



140 PBRROMAONBTISM— INTRINSIC FIELDS: TERRY 

at the intersections of a space lattice with their corresponding axes 
parallel. 

By applying the laws of statistical mechanics to a system of such 
complexes, relations are obtained between magnetic and thermal quan- 
tities, similar in form to those of Weiss, but which are somewhat more 
comprehensive. From stability considerations, he is able to deduce 
the hysteresis curve to obtain a relation between coercivity and 
temperature, and to determine the number of magnetons per unit 
volume and the magnetic moment per magneton. 

The chief difference between the Weiss theory and that of Gans, 
briefly stated, is as follows: In the former, the exciting field, acting at 
a definite point within a ferromagnetic body, is composed of two parts, 
the external field H, and the molecular field N M, where M is the 
intensity of magnetization and N is a constant characteristic of the 
substance. In the Gans theory, the exciting field consists of three 
parts, the external field H, the "structure field," due to the gross mag- 
netization of the body, which, by a treatment similar to that of Lorents 
for dielectrics, is found to be 

-tM. 

and a molecular field A due solely to the action of the magnetons of the 
particular complex in which the magneton under consideration is lo- 
cated. It is assumed that each direction for the molecular field A is 
equally probable, and that its magnitude is independent of direction. 
The molecular field, on account of the different directions which it 
assumes, has a tendency for disorganization and acts, therefore, in the 
same sense as the thermal agitation. At high temperatures, the action 
of the molecular field may be neglected in comparison to the thermal 
agitation, while at low temperatures, thermal agitation may be neglected 
in comparison to the molecular field. 

The equation for the magnetization curve for a ferromagnetic sub- 
stance may be deduced in the following manner:^ The magnetic moment 
of the magnetons of a particular group has, from symmetry considera- 
tions, the direction of the resultant field F, which is obtained by vec- 
torial addition of E and A, where E is the sum of the external and struc- 
ture fields, and is equal to 

H+^tM 

and A is the molecular field. This is shown in Fig. 3, section III of the 
report on kinetic theories of dia- and paramagnetism by Dr. Wills. 

> cf . p. 46 of this report. 



FERROMAONETISM— INTRINSIC FIELDS: TERRY 141 

When the component of this magnetic moment is taken in the direc- 
tion of the external field and the smnmation extended to all the groups 
included within a unit volume of the substance, its intensity of magneti- 
zation is obtained. It is shown by equation (32) of the above reference, 
that the average value of cos d, where d is the angle between the axis 
of a magneton and the external field, is: 

1 /•• r(A+K) 

(1) cosd=;^J WJA)_dA / (cotha--)(F«+K«-A«)dF. 

Jo A J ±(A-K) * 

where W (A) dA denotes the probability that the molecular field A 
lies between the limits A and A+d A, and 

kT 

In carrying out this integration, the positive sign of the lower limit 
should be used for K<A and the negative for K>A. 

Since it is assumed that the molecular field is constant in magnitude 
and that all directions are equally probable, 'equation (1) reduces to: 



rCA+K) 

(2) ^^d = 7^ / (coth a - -) (F 

4 K« y ^^^_K) a 



i+K*-A*)dF. 



The magnetic moment per unit volume will, therefore, be given by: 



M, 



/(A+K) 
(coth a—-] 
±(A-K) * 



(3) M = NMC0S^=7-r^ / (cotha— )(F«+K*-A«) d F, 



where Mo equals N n. Since 

K=H+|irM, 

this relation, together with equation (3), gives M as a function of H, 
and the magnetization curve may accordingly be deduced. It may be 
shown that for A = 0, equation (3) reduces to that of Langevin. 

To apply this formula to a ferromagnetic body and to see how the 
phenomenon of hysteresis is concluded, let us think of a ferromagnetic 
crystal having a rhombic space lattice such as pyrrhotite, with eUip- 
soidal elementary complexes situated at the intersections with corre- 
sponding axes parallel. Let the magnetization and field strength at 
points within the complexes be designated by M^ and H\ respectively. 



142 FBRROMAGNETISM-'INTRINSIC FIELDS: TERRY 

and let M and H refer to the corresponding quantities at points within 
the crystal but outside the complexes. We may then write : 

H/-H.+N/M„ 

where N/, N't, Ni' are constants depending upon the structure. 
Further: • 

M = nVM' 

where n is the number of elementary complex per unit volume and V is 
the voliune of a single complex. 
The quantity K of equation (3) is defined by: 

K=H'+~tM'; 

but may be expressed in terms of H and M by the following relations: 

K,=H,+NiM., 

K,=Hy+N,M„ 

K.=H.+N,M., 
where 

N.=N.'+3^; N.=N,'+^; N.-W+g^. 

K may be regarded as the directive part of the total force acting on 
the magnetons of a complex and is made up of the external field H within 
the crystal and another field having components Ni M^, Nt M,, Ni M 
which depends essentially upon the form and arrangement of the 
elementary complexes and which may appropriately be named the 
" Structure " field. 

The magnetization curve, i.e. the M, H curve for a crystal in the 
direction of one of the axes of symmetry, e.g. the X axis, may be ob- 
tained from the M K curve by a shearing process as follows: 

Let the dotted curve of Fig. 7 be that given by equation 3, and let 
S S' be the shearing line inclined to the O M axis by an angle such that 
tan a — Ni. 



. FERROMAGNETISM^INTRINSIC FIELDS: TERRY 



143 



If P is a point on the M K cnrvey then P' is the corresponding point 
on the MH curve, where PP'=QR. The shearing angle a depends 
upon the structure constant N. Two cases are to be considered, i.e. 
a <P, and a >P, where p is the angle between the tangent to the M K 




Fig. 7 

curve at the origin and the O M axis. In the first case the M H curve 
lies entirely in the first quadrant; but in the second it follows the path 
O C D of Fig. 8 ^. From stability considerations it may be shown that 



M 



ik 





Fio. 8 



for a </3 the magnetons of the elementary complexes are in stable 
equilibriimi throughout the entire range of field strengths and that the 
substance is paramagnetic. - On the other hand, when a>P, between the 
fields designated by the vertical tangents at the points C C\ the equili- 



144 



PBRROMAGNETISM—INTRINSIC FIELDS: TERRY 



brium is labile. The substance is then ferroniagnetic and exhibits the 
properties of hysteresis, as indicated by the curve. 

By developing the integrand of equation (3) in a power series and 
making certain approximations to simplify the integrations, Gans has 
deduced a number of important relations between magnetic properties 
and temperature. For example, he has deduced equations connecting 
retentivity and temperature, coercive force and temperature, and 
obtained a relation between susceptibility and temperature for a fer- 
romagnetic substance above the Curie point. The first of these is 
substantially the same as obtained by Weiss and is in good agreement 
with the observations of Weiss' and Foex for magnetite but not for iron 
or nickle. The second and third relations are in good agreement with 
the results of Terry' for iron, nickel, and cobalt at high temperatures. 

The Theory of Honda and OkAbo. 

In contrast to the theory of Weiss, in which molecular fields of the 
order of several million gauss are assumed to be acting, an attempt has 




Fig. 



been made by Honda and OkAbo,' following the ideas of Ewing, to 
deduce the curves of magnetization and hysteresis and to explain the 

1 Weifls and Fote, Arch, dea Sei. Phyt. el Nat., 31, p. 4. 1911. 
'Terry, Phyt. Ret. 33, No. 2, 1910 and 60, N. S. No. 6. p. 394. 1917. 
* Science ReporU Tohoku Univ. s, No. 3. p. 153, 1916. 



PERROMAGNETISM^INTRINSIC FIELDS: TERRY 145 

properties of crystals by taking account of the mutual actions of mag- 
netic molecules whose poles act according to the law of inverse squares. 
For this purpose they have considered a Ewing model of nine coplanar 
magnets placed at the comers of a square space lattice as shown in Fig. 9. 
Although the real problem is three dimensional, a study of the two 
dimensional case is sufficient to indicate the degree of success to be 
expected from such a theory. If no external field acts, the elementary 
magnets take positions of stable equilibriiun parallel to one of the sides of 
the space elattice. Under the action of a field, however, the group turn 
as a whole toward the direction of the field and takes an equilibrium 
position determined by it and the mutual actions of the group. 

To make the problem definite, let the origin of coordinates be at the 
center of the magnet P R and let an external field H act in a direction a 
with respect to the Y axis, and suppose the elementary magnets to be 
turned through an angle 6 in consequence. Let 2a, 2r and m be the 

sides of the space lattice, the length of an elementary magnet, and the 

a 
pole strength respectively, and put - = k. 

The position of equilibrium of one of the magnets such as P R may 
be determined by equating the torque due to the external field to that of 
the 16 remaining poles of the group. The restoring torque is obviously 
a function of 40 since the magnets of a square space lattice are in equilib- 
rium when they stand end to end; the equilibrium being stable when 
they are parallel to one of the axes of coordinates, and unstable when 
parallel to the diagonals. The analysis shows that the equilibrium con- 
dition may be written : 

(1) Hsin(a-0) = A8in40, 

where A = -^(K) is a quantity depending upon the strength of the 

elementary magnets and their particular arrangement within the group. 
The intensity of magnetization I in the direction of the applied field is: 

(2) I = 2mrnco8 (a— 0) = I^cos {a— 6), 

where n is the number of elementary magnets and Iq the saturation value 
of the intensity of magnetization. 

I H 

(3) Using r = i> and -=h, 

lo A 

as " reduced " values of the intensity and field respectively, we have 
the relations: 

(4) i= cos (a— 0), 



146 PERROMAONBTISM— INTRINSIC FIELDS: TERRY 

(5) and h sin (a—d) ^ mx4$, 

as the equations defining the magnetization of a simple complex. If 
h and a are given, equation (5) gives the value of tf, and this, when sub- 
stituted in equation (4), gives the value of i. Equation (5) is, however, 
of the eighth degree in sin tf or cos 6 and must therefore be solved by an 
indirect process. It is necessary, first to point out the way in which an 
elementary complex behaves when acted upon by external fields of 
various magnitudes in different directions. As indicated by equation 
(1) the restoring torque on each magnet due to the mutual actions of the 

group is a function of period -. It is a maximum for angles of - with 

the sides, and reverses sign at angles of -. Let us suppose that the 

4 

magnets are originally parallel to Y and that a field h acts at an angle a 

and rotates them through $. Four cases present themselves. 

Com 1. O < a < T. The component magnetization in the direction of h 

4 

starts with the value i » cos$, increases continuously with h and becomes 

unity for h» oo. 

IT W 

Case 2. z<^<^' 1^® magnetization increases continuously with h 

until the deflecting torque exceeds the restoring torque, when the magnets 
jump to a new position of equilibrium between h and X. This new posi- 
tion is the same as though the magnets had remained in their original 

IT 

positions and a were changed to a—-. There results a discontinuous 
increase in i. For angles a in this octant, the jump occurs for values of 

IT 

B in excess of - . With further increase in h, i increases continuously 

to unity as h approaches infinity. 

Case 5. ;;<«<— -. The magnetization increases continuously with h 
2 4 

until the restoring torque is exceeded by the deflecting torque when a 

discontinuity occurs, and the magnetization follows the same course as 

IT 

though a were replaced by a—-. This case is similar to case 2, except 

IT 

that in the new equilibriiun position t is greater than - . 

3t 
Case 4' — <a<T. The magnetization up to the discontinuity is the 
4 

same as in the above cases. The discontinuity, however, may be of 



PERROMAGNETISM^INTRINSIC FIELDS: TERRY 147 

two types. For directions of h somewhat greater than -7 the torque ia 

4 

It 5t 

greater for the Tnaximum near - than for the one near -- ; the magnets 

5t 
jump to a position somewhat less than — and the subsequent magnetiza^ 

o 

tion takes place as though a were replaced by a-* - as in case 3. If, on 

the other hand, a lies in the neighborhood of t, the torque is greater 

5t it 

near -- than r and the magnets jump to a position between h and the 

o o 

negative Y axis, and the subsequent magnetization takes place as though 
a were replaced by a— IT. 

The field h„ at which the discontinuity occurs, may be obtained in 
the following way. Since 

sin4 
sm {a— 6) 

the value of 6 for which h is a maximum is given by: 

dh 5 sin (a+3^)+3 sin (a-5 6) 



(7) 



de 2sin*(a-d) 



CaUing this d^, there results: 

(8) 5 sin (a-3 0+3 sin (a-6 0=0. 

The field h„ is obtained by solving this equation for ^o ^^d substituting^ 
in (6). 

We are now in a position to study the magnetization of a ferromag- 
netic mass consisting of a large number of elementary complexes with 
their space lattices distributed uniformly in all directions in a plane. 
Let N be the number of complexes, and d N the number whose axes 
make with a certain direction an angle between a and a+d a when no 
external field is acting. Then: 

(9) dN=^da. 

Let M be the moment of a complex, a the angle between its initial 
direction and that of the external field h, and let it be turned through. 



148 PERROMAGNBTISM— INTRINSIC FIELDS: TERRY 

an angle 6 by the action of this field. In the direction of the field its 
component is M cos (a— 0). The magnetization due to all the complexes 
is: 

(10) 1 = 2 /^cos(a-d)da=- / cos (a-^) da, 



where Io»MN is the saturation value of the magnetization. The 
reduced magnetization i is given by: 

1 /■• 
<11) i==" / cos (a— 6) d a. 

This, together with equation (80) furnishes the solution to the problem 
of finding the equation for the magnetization curve. That is, for a 
given value of h, 6 may be found from (6) in terms of a, and this value 
when substituted in (11) gives i. Owing to the discontinuities in 6 
discussed above, it is, however, necessary to consider the problem for 
large and small values of h separately. 

When h is small, d is also small, and we may put sin 4 0~4 0. Equa- 
tion (80) then becomes: 

(12) h (sin a—e cos a) =4 6; 

whence 

h sin a 



4+h cos a 



Substituting in equation (11) there results: 



1 /■' 
i = - / (cos a 



i = - / (cos a+d sin a) da 



^ V 1 f'/ h sin* a v , 

(13) =-/ (cos «+-———) d a 

rJo 4+n cos a 

1 /"' h C"" h 

= - / cos a d a+— / sin* a (1+ - cos a) "* d a. 
tJq AtcJq 4 

The first integral vanishes and the second, when expanded in a power 
deries and integrated, gives 



FERROMAGNETISM— INTRINSIC FIELDS: TERRY 149 



(14) 



= .125 h+.00196 h«+.00007 h*+ 



The intensity i is here expressed as an odd function of h and is nearly 
linear in the neighborhood of the origin with an upward concavity which 
increases with h. It approximates well the experimentally determined 
curves. 

The solution for large values of h is complicated by the abrupt changes 
in the value of d. Further, the angle at which these discontinuities 
occur depends upon both the external field and the orientation of the 
complex. It is therefore necessary, in evaluating (11) to divide the 
integration interval into several parts. For a given h, the critical 
angles may be determined from equations (8) and (6), a study of which 
shows that, for reduced fields slightly in excess of unity, there will be 
three such angles, giving four integration intervals. Calling these 
angles ai, as, and at we have : 



"« frn-ftftf. 



«i "^ «« '^ as 



For the complexes l3ning within the intervals of the first and fourth 
integrals, the magnets remain stable since the torque due to the external 
field does not exceed the restoring torque. For the complexes of the 

second integral, the magnets make jumps of - as explained in cases 2 and 

3 above, and the integration limits must be changed from ai and at, 

IT X 

to ai— - and aj— ~, respectively. For the third integral, the magnets 

lie beyond the first and second positions of stable equilibrium, and jump 
by an angle t. The limits accordingly must be changed to as— x and 
at— IT, respectively. 

The integrand of equation (11) contains 6 and the evaluation can be 
effected more easily in terms of this variable than of a. The elimination 
of a may be made as follows: Differentiating (6) with respect to 6, 
there results: 



■-At-^) 



h cos (a— ^) I T-— 1 j"=4 cos 40; 



da 4 cos 4 

whence -r = , ; ^, + 1 . 

d^ h cos (a— 0) 



FBRBOMAONETISM— INTRINSIC FIELDS; TBRRY 



. 1 fjicat*! 1 ;- — r-T—\, 

The new iategratton limits coTresponding to m, a*, and ai for given 
values of b may be obtained by aubetituting theae values successively 
in equation (6) and solving for S. When this has been done, there 
results: 

From equation (90): 



(18) i-l{»m«J±i/;Vl-lrin.«4 
The int^ral in this equation may be written: 

(19) ; j y 1 - k» sin* « dfl- y Vl - k» 8in» « dS, 

where k*<=r,. These are elliptic integrals of the second kind 'with 
modulus k, and may be written: 

^|ECk,4^-E(k,4ff)l. 

Expanding E as a power series in k and determining the appropriate 
limits of in equation (17) from equations (8) and (6), Honda and Okubo 
have computed ihe intensities corresponding to four different values of h. 
The results are given in Table I and plotted in Figure 10 which is seen to 
possess, in a marked degree, the characteristics of the experimentally 
determined magnetization curve for a ferromagnetic substance. 

Table I 



PBRROMAGNETISM^INTRINSIC FIELDS: TERRY 151 

The residual magnetism to be expected on the basis of this theory 
may be obtained as follows : When h has been made infinite the mag- 

nets of all the complexes having orientations between d= 7 and ± -7- take 

4 4 

new positions of equilibrium corresponding to discontinuous rotations 
of - with respect to their initial positions, while those lying between 

d= -r and t jump by t. When the field is reduced to zero, all the 
4 

magnets then behave in the same manner as those l3ning between zero 

and 7 which return reversibly to their original positions. The residual 
4 

magnetism R is then given by: 

w 

(20) R-2f M COB tfdN, where dN-^dtf 



T 



IT J o 



coeSde^ 



-4Io. 



x> 



W2 



and the reduced residual magnetism r is: 

R 
r=--.8927. 

The portion of the hysteresis curve l3ning between the retentivity 
point and maximum induction may be deduced by considering that the 
magnetization process in this interval takes place reversibly and that 

all the complexes have initial orientations lying between ±7 with respect 

to the direction of the field. The law of magnetization is then given by 
the equations : 



4 r* wxAB 

i= ~ / cos (a—d) d a, and h = ": — z r^- 

Tj o sm (a-e) 



(21) For h smaU we have: 



1 r* h . 

i = - / (h+4 cos a) (1+- cos a)"* d 
^y o 4 



= .8927+.047h-.083h«. 



152 



FERROMAONBTISM— INTRINSIC FIELDS: TERRY 



For larger value of h, equation (19) must be used where the proper 
limits of intergation are obtained from equations (8) and (6). The 
portion of the hysteresis curve for negative values of h is obtained by 
assuming that the case is equivalent to the magnetization by a positive 











• 

I 
1/1 










- 








^ 


ID 




J 


^^ 


^ 








4 


a 

3& 




A 


T 




■ 










[_ 


— ^ 


tf 














( 




J^ 


y 








i, 


r 


4 


3 


2 

i- 


« 


1 


i 


3 


4 


S 






-y 


t 


— 4 

— 




t 








# 


^ 


/ 


__ 




W 


f 






' 










u 

































Fig. 10 



field of a group of complexes whose initial magnetic directions are 

3 T 5 T 
uniformly distributed between the angles — and — . 

The results of calculations are shown in Table II and plotted in 
Figure 10. 



FERROMAGNETISM^INTRINSIC FIELDS: TERRY 



153 



Table II 



h 


• 

1 


h 


• 

1 


+0.0 


1.000 


-1.0 


0.815 


3.5 


0.973 


-1.5 


0.015 


3.0 


0.962 


-2.0 


-0.584 


2.5 


0.956 


-2.5 


-0.786 


2.0 


0.944 


-3.0 


-0.847 


1.5 


0.932 


-5.0 


-0.981 


1.0 


0.922 


— « 


-1.000 


0.0 


0.893 







The similarity between these curves and the curves of experiment is 
striking. The most important departm^ is probably the large value of 
the retentivity. For the curves here deduced the remanence is 89 per 
cent, while in practice one seldom finds a value greater than 60 per cent. 
This discrepancy is probably due to the fact that in this theory no ac- 
count is taken of thermal agitation. Hysteresis phenomena are assumed 
to take place only when the molecular magnets turn abruptly through 

angles of x or t, otherwise the processes are reversible. The energy 

losses due to hysteresis must be accounted for by the kinetic energy 
acquired by the magnets during these jumps which is then dissipated by 
friction, radiation or some other process. 

Honda and Okiibo have extended their study to the case of magnetic 
crystals. For this purpose, the only change it is necessary to make for 
those of the rectangular system, such as Magnetitie and Hematite is 
that all the elementary groups are oriented in the same direction instead 
of at random as in the case discussed above. For Pyrrhotite, a hexa- 

gonal space lattice must be used for which F (0) has a period of '. By 

this means they have deduced the results of Weiss, Quittner and Kunz 
on these crystals with the same degree of accuracy as was obtained in 
the case of ordinary ferromagnetic substances. 

The Mean Molecular Field of Diamagnetic Substances. 

In the resume of the Weiss theory it was pointed out that many of 
the phenomena of ferromagnetism may be explained in terms of the 
laws of paramagnetism by the introduction of an internal or molecular 
field due to the presence of surrounding molecules. Langevin has indi- 
cated that the origin of the magnetic properties of both para- and 
diamagnetic substances is to be found in the rotation without damping 
of electrons in closed orbits about the positive nuclei. If the arrange- 
ment of the orbits possesses complete symmetry, the resultant magnetic 
moment and hence the field at distances large compared to molecular 



154 PERROMAGNBTISM^INTRINSIC FIELDS: TERRY 

magnitudes ia lero, and the substance is diamagnetic. If, on the other 
hand, there is a lack of symmetry in the orbital arrangement, the field 
at a distance is not zero, and the substance is paramagnetic. The 
pondermotive action of repulsion exhibited by diamagnetic substances 
when introduced into a magnetic field is accounted for by assuming 
changes in the electronic orbits in accordance with the ordinary laws of 
induced currents in a manner analogous to the explanation of the 
Zeeman effect given by Lorentz. 

In his theory of diamagnetism, Langevin has considered the effect of 
the external field only and has not taken into account the action of 
neighboring molecules when the substance is polarized. The fact that the 
Zeeman effect and the rotation of the plane of polarization, both closely 
related to diamagnetism are, in the case of ferromagnetic substances, 
proportional to the intensity of magnetization and not to the applied 
external field would indicate that in diamagnetism also, the suscepti- 
bility should be a function of the state of polarization. Inasmuch as 
the forces of diamagnetic repulsion are small and the susceptibility is 
in general independent of the temperature, the existence of an internal 
or molecular field would be difiScult to prove. Nevertheless with a 
change in aggregation, such ais accompanies the transition from the 
liquid to the crystalline state, one should expect, if such a field exists, a 
measureable change in susceptibility, due to the distortion of the 
electronic orbits caused by the effects of the magnetic fields resulting 
from the new state of polarization. 

Oxley^ has investigated a large number of diamagnetic substances 
and has found that with few exceptions there is a decrease in diamag- 
netic susceptibility of about 6 per cent, when the substance passes from 
the liquid to the crystalline state. On the theoretical side he has ex 
tended the method of Langevin by the introduction of an internal field 
depending upon the polarization to accoimt for this discontinuity at 
the transition. This extension to the theory is as follows : 

Instead of assuming, as Langevin did, that the force acting on any 
electron of a rotating group, is simply e E, where E is the electric field 
strength and e the charge on the electron, he assumes, with Lorentz, 
that it is given by 

e (E-hf (P)) 

where P is the electric polarization of the mediiun and f (P) a function 
which characterizes the grouping of the molecules for a given substance. 
The crystalline state may be regarded as isotropic to a first approxima- 
tion since the crystab will have all possible orientations. The effect 

I Oxley, PhU. TranB. Roy. Soe., 214, p. 100. 1914; 215, p. 79. 1914; 220, p. 247. 102a 
Proe. Roy- Soe, A,, 95, p. 68, 1918. 



PERROMAGNETISM-'INTRINSIC FIELDS: TERRY 165 

due to the modification of the internal motions of an atom or molecule 
by the process of crystallation will be taken into account by a change in 
the value of f (P). Following the theory of Langevin, let (a, b, c,) be 
the coordinates of the center of gravity of a molecule and (x, y, z,) those 
of a particular electron. Also let (f , 17, f ) = (x-a, y-b, z-c) be the coor- 
dinates of an electron with respect to the center of gravity of the mole- 
cule in which it is situated. Since the medium is homogeneous and 
isotropic, 

(1) 2f=2;i7=2f=2fi7=2i7f=2ff=0. 

The sectorial velocity of an electron with reference to the center of 
gravity of the molecule will have a component along o z given by: 

(2) Q.«-(fA-nf), 

and the component of the magnetic moment of the molecule along this 
axis is then: 

(3) M.=2eQ.. 
From (2) and (3) there results: 

(4) M.=|2(fA-nf). 

Let X, Y, Z, be the components of the internal forces determined by 
the configuration of the molecules which act upon the electron of mass 
m and let E and H be the total electric and magnetic fields respectively. 
If the origin moves with a velocity having components u, v, w, then 
the equations of motion are: 

m f =X+e [E,+f (P,)]+e H. (v+y)-e Hy (w+z)-m i-m li; 
(5) 

m i) = Y+e [Ey+f (Py)l+e H, (w+i)-e H. (u+x)-m b-m v. 

These equations differ from those given by Langevin only in the 
addition of the term f (P). Because of the smaU dimensions of the 
elementary system considered, the electric force and the polarization 
will be nearly constant throughout its extent, and, designating their 



z 



+ 



156 FERROMAQNETI8M— INTRINSIC FIELDS: TERRY 

values at the center of the system by Eo and f (Po) respectively, we may, 
by expanding and neglecting powers higher than the first, write: 

Calciilating M from the above equations, there results: 

«-£[*{(t)r(f)i-4tHt)} 

-Kt).^t).-«-^] 

where ^ =2 p=2 *i7=2 f*. The last term of (8) is zero provided each 

molecule has no initial moment as Langevin's theory requires. Dropn 
ping the subscript and using the electromagnetic field equations: 

(9) curl E=H-, and div H=0, 

their results: 

Intergrating from the time (H>=0) to r (H«H.) their results: 

(11) AM.- -|^H.A+^/;[±f (P,)- Af (P.)]dt. 

where A M. is the magnetic moment produced in the molecule by the 
change in field which occurred during the interval. The second term 
depends upon the molecular configuration of the substance and implies a 
modification of the electron circuits which will change their self induc- 
tance. Any such change of self inductance may be represented by a 
small change in the intensity of the applied magnetic field, and we may 
then write: 

(12) f(P)-aP, 



FBKROMAGNETISM^INTRINSIC FIELDS: TERRY 167 

where "a" characterizes the grouping of the molecules. Accordingly: 

m if(P,,-|f(P.,-a(fi-a)._.|(fflO, 

where a (dH,) is the elementary change in the external field during a 

small interval of time r. 

Therefore: 

(14) AM.- -£H.A-^/;i(aH.) d. 



-^['+^]- 



The term q A H, is the total variation of H. caused by the distortion of 
the electron orbits. If N is the number of molecules per gram, the 
specific susceptibiUty may be written: 

.... NAM, Ne^Ar,. AH,1 

(15) x = -H^ = — 4^Ll+a^J. 

An expression is thus obtained in which the susceptibiUty is shown to 
depend by means of the quantity "a" upon the state of polarization of 
the substance, and the term a AH, is the molecular field produced 
thereby. Ifa=0, (15) reduces to the expression originally obtained by 
Langevin. Calling ai and ae the polarization constants for the liquid 
and crystalline states respectively, the variation of x on crystallization 
may be written: 

(16) «2=(a.-aO^'. 

It has been shown by Larmor^ that ai is of the order ~ for most liquids* 

The value of ac is large but its exact determination in any particular 
case is difficult since it depends upon the actual distribution of the 
molecules about which we know relatively Uttle. It is possible, how- 
ever, to obtain an approximate value of its magnitude from the work of 
Cbaudier' on the change of magnetic rotatory power with change of 
state. He has shown that a^ must be at least of the order 10* and ia 

A TT 

probably larger. * is accordingly of the magnitude of 5x10"^. 



1 



■PAtl. Ttom. Roy, 8oc„ 1897, A, p. 213. 
CampUa, Rend., 156, p. 1008, 1913. 



158 FBRBOUAONETlSM-lNTRIffSlC FIELDS: TERRY 

A comporiBDD o( the molecular field for dianugDetic nibstanoea with 
that of ferromagQetic mibetancce according to the Weiae theory mar ^ 
made as followg: For a aupercooled hquid, we may write: 



(17) 



while i<H cryrtala at the tame temperature x. is given by equation (15). 
Hence: 



.-.(...^-|L-) 



(19) whence H. x,-x, (H.+a, AH,). 

The term a, A H, ia the mean molecular field of the diamagnetic crystals. 
Since in equation (6) of the Weiss theory, the molecular field coDstant, 
which we will here designate as N*, ia taken as the proportionalty factor 
beween molecular field and intensity, while in equation (19), a, dH, is 
itself the molecular field, it is necessary to compare N* with a,' irtioe 
the latter is defined by equation: 

(20) a, AH,- a,' N AM. p 

in which p, the density of the aubetance, is approximately unity fw 
the crystals investigated by Oxiey. By using the first relation <rf 

equation (15) and putting -~— '•-5x10'* there results: 



Assuming x~5 * ^0~^> *od a,- 10*, a,' is found to be ctf the ordo* 10*, 
which is of the same order as the values of N* given by Weiss and Beck. 

The Local Molecular Field. 

In the above discussion of the mean molecular field, it was pcnnted out 

that the change of susceptibihty which accompanies the transition from 

the linuid to the crvHtallme state can be satisfactorily interpreted in 

Id appreciable only in the crystalline state, 

kgnetic&lly by a term a« A H,. The nature 

1 further than to say that it ia of such a 

hin the crystal a distortion or polariiation 



PERROMAGNETISM—INTRINSIC FIELDS: TERRY 169 

equivalent to that actually produced by the molecular forces of the 
molecules of the crystalline structure. 

On the theory of magnetism developed by Langevin a diamagnetic 
molecule contains oppositely spinning systems of electrons which 
counter balance each other at distances large compared to molecular 
dimensions, but which nevertheless produce fields close to the molecules 
which may be very large. Each molecule of a crsrstal is accordingly 
subjected to the intense magnetic fields of its neighbors and the resulting 
distortion in the electron orbits may account for the shifting of an absorp- 
tion band when a liquid crystallizes, and the natural double refraction 
of crystals. The direction of this local field will alternate as we pass 
from molecule to molecule through the space lattice, and is distinguished 
from the mean molecular field in that it exists whether an external field 
is acting or not. The forces, due to these mutual magnetic actions, are 
responsible for the rigidity of cr^rstals and the existence of plane of 
cleavage. 

To obtain an idea of the intensity of the local moleciilar field, we as- 
sume that it is of such a magnitude as to produce a change in suscepti- 
bility of the order of that actually observed in the crystallization experi- 
ments. 

From the theory of Langevin, we have: 

(22) ^"-?^^ 

M 4rm 

where A M is the change in the magnetic moment of an electron orbit 
of moment M by the application of the field H; r, the period of an elec- 

tron, and — the ratio of the charge to its mass. From equation (22) 
m 

we have: 

(23) ^'"f^"' 

Ml 4rm 

and 

AMe_ Hre 

M« 4 T m' 

where the subscript 1 and c refer to the liquid and crystalline states 
respectively. In passing from the Uquid to the cr3rstalline state the 
alteration of (Mi) produced by the local molecular field H, is A M/, 
where: 

(24) ^M/ ^ erHo 

Ml 4 T m' 



160 FERROMAGNETISM— INTRINSIC FIELDS: TERRY 

and 

(25) Me=-Mi±AMi'. 

^though He alternates as we pass from molecule to molecule, the sign 
of A Mi^ will remain the same, for when He' changes sign, Mi reverses 
also so that every molecule suffers the same distortion due to the local 
molecular field. The double sign implies that the arrangement of 
molecules due to their particular kind of packing will be such that in 
some cases hx is positive and in others, negative. From equation (24) 
and (25) we find that : 



m m..m,(i±2l&); 



also that: 



(27) 



AMc-AMi Te/ldberiH 



AM 



LMi_Te/ ld:eTiHe \ ^ 

1 ri\ 4 T m / 



The electrons which give rise to diamagnetism also produce the 
Zeeman effect, a sUght change in frequency being responsible for both 
phenomena. We may, therefore, write Te=Tii:5r, where 5r is the 
change in period produced by the local molecular field H^ when crystal- 
hzation sets in. From equation (15) it follows that 

(28) xc= -gp A Me, xi = ^ A Ml, and 

5x = Xc-X=~(AMe-AMi), 

where n is the number of electrons per molecule and N the number of 
molecules per gram. The change of period dr is defined by: 



(29) 



gr e Ti He 
r 4 T m 



From equations (27), (28), and (29) it follows that: 

(30) »?=(i±«_:i^.)(i±llLl!)_i. 

X \ 4Tm/\ 4Tm/ 

This equation gives the order of magnitude of the local field Ha in toms 



PERROMAGNETISM— INTRINSIC FIELDS: TERRY 161 

of the percentage change in x on crystallization. In all the substances 
investigated this change amounts to a few per cent. Hence: 

1 _ e^r»He' 
100'"l6ir»m«' 

Taking n = 10"" seconds, and — = 2. X 10^ we get: 

m 

He =6X10^ gauss. 

We have no data at present as to how far an absorption line is shifted 
when a substance passes from the liquid to the crystalline state, but such 
evidence would be a direct test of the magnitude of He. On the other 
hand, it is known that the magnetic double refraction induced in a 
liquid is proportional to the square of the external field. If we assume 
that this law holds up to fields of the order 10^, we should expect on the 
basis of the local field idea for a crystal, a double refraction about 
40,000 times as great as the largest values induced in a hquid. This is 
about the ratio of the double refractions of nitrobenzene subjected to a 
field of 3X 10* gausses and the natural double refraction of quartz. The 
fact that most uniaxial crystals have a double refraction comparable 
to that of quartz, and hence, a magnitude much greater than that 
induced in liquids by fields available in the laboratory would support 
the idea that the intrinsic molecular field, if interpreted magnetically, 
must be of an order high compared to 3X10*. These fields are even 
larger than those observed for ferromagnetic substances when inter- 
preted according to the Weiss theory. 

The Stresses and Energy Associated with the Molecular Field. 

If there exists a molecular field of the order deduced in the previous 
sections, then the forces associated with the diamagnetic crystalline 
structure must be very large and the potential energy of the crystallire 
state will be considerable. It should, therefore, be possible to give a 
rough check on the value of the local molecular field from a consideration 
of the latent heat of fusion of crystals. If |i| is the local magnetic 
moment which in conjunction with the local field Ho, binds one molecule 
to another in the crystalline structure, and if all the elementary systems 
are independent, then the energy possessed by one gram of the substance 
in virtue of a particular crystalline grouping, may be written: 



m E- t n 



2po 



162 FERROMAGNETISM—INTRINSIC FIELDS: TERRY 

where n is the number of molecules per cc, p the density, and I = n |i 
the aggregate of the local intensity of magnetization per cc. Here a/ 
IB the constant of the local molecular field as used above. The local 
molecular field H^^h^' I has been shown to be of the order 10^, and 
since a^' is of order 10*, it follows that I is of order 10*. Hence, the 
energy per gram given by equation (31) is of order of 10*, the thermal 
equivalent of which is approximately 25 calories. This represents the 
energy necessary to destroy the crystalline structure, that is, the latent 
heat of fusion. It is of the right order of magnitude since a large 
niunber of diamagnetic crystalline substances have latent heats ranging 
from 21 for aniline to 44 for acetic acid. It is also the order of mag- 
nitude of the latent heat of transformation of iron from the ferro-to 
the paramagnetic state as found by Weiss and Beck. It is obvious that 
until we know the arrangement within the cr3rstalline structure the 
value of ae must necesssarily be merely an approximation; but the fact 
that it agrees even as regards the order of magnitude is good evidence 
for the existence of such local molecular fields and intensities as have 
been assumed. 

Molecular Field and Tensile Strength. 

Whatever may be the nature of the forces which hold the molecules 
of a liquid together, we have in addition to them, on crystallization, 
those of the intrinsic local field. If it is assumed that the only addi- 
tional forces binding molecules together on crystallization are those 
due to their magnetic fields, then it should be possible to predict their 
tensile strengths from considerations of their local fields and intensities 
of magnetization. The potential energy associated with each unit 
volume of a crystalline substance in addition to that when in the liquid 

form wiU be 

1 

2 



^H« I. 



This is then a measure of the mechanical stress which binds the molecules 
together and determines the rigidity of the substance. In a previous 
section it has been shown that for diamagnetic substances I is of the 
order of 10* and since H^ is of order 10' it follows that the tensile strength 
should be of the order .5X 10' dynes per squares centimeter. That this 
is of the order experimentally determined in some cases may be seen by 
comparing with glass Ll-LSXlV, quartz 10X10", lead .16X10*, etc. 
Moreover if one uses the corresponding values of intensity and molecular 
field for ferromagnetic substances as determined by Weiss, he obtains 
the following values for tensile strength: iron, 5.5X10*, nickel 1.4X10* 
and aubalt 4.4 X 10* which compare favorably with the observed values. 



FBRROMAGNETISM—INTRINSIC FIELDS: TERRY 163 

It may then be concluded that the stresses due to the local molecular 
field give a satisfactory interpretation of ultimate tensile strength of 
crystalline media for both dia-and ferromagnetic substances. 

The Change of Density on CrystaUization Interpreted as a 
Magnetostriction EifFect of the Molecular Field. 

It has been shown by Larmor^ that the potential energy per gram of 
a diamagnetic liquid, the molecules of which have a small mutual in* 
fiuence, is 

(32) ^ [Ki W+\ Ki* m , 

where Ki is the susceptibiUty per unit volume and X is a constant approxi- 
mately equal to - * If now a liquid is subjected to a magnetic field a 

change of volume occurs such that the internal pressure is reduced by an 
amount equal to the potential energy per unit volume of the magnetic 
field. Since Ki is of the order of -7X10"^, the second term of (32) is 
negligible compared to the first, and if C is the compressibiUty of the 
liquid, the change in volume due to the field may be written: 

(33) 5V=~CKiff: 

a relation which has been verified by Quincke for fields up to 50,000 
Gauss. If it is assumed that this law holds for fields of the order of 
the local molecular fields, i.e. 10^ gauss, then the change of volume on 
crystallization may be computed by replacing the first term of equation 
(32) by the second expression of equation (31). There results then: 

(34) 5V=^Cae'P. 

From considerations involving the determination of the quantities 
ae' and I from internal stresses accompanying the change of freezing 
point with pressure, Oxley deduced for the substances listed below the 
following values: 

ae' = 2.5X10*, and 1=400. 

Since C for these substances is of the order .8X10"^", there results: 

d V=i .8XlO-*«X2.5X10*X16X10i"«.16 cc. 

> Lsnnor, Proc. Roy. 8oc, A., 52, p. 63, 1802. 



164 FBRROMAONETISM— INTRINSIC FIELDS: TERRY 

The following are observed values of 3 V for a few substances. 



SvbaianeeB (V 

Benxene 10 

Naphthalene 14 

Benxophenone 19 

Formic acid 10 

Di-phenylamine 10 

The calculated values agree as well as could be expected with the 
observed values, since, for a^' and I, we know the orders of magnitude 
only, since they are unknown functions of the molecular structure and 
the space lattice which are different for each substance. 



THEORIES OF MAGNETIC CRYSTALS AND MAGNETON: KUNZ 166 

THEORIES OF MAGNETIC CRYSTAI5 AND THE 

MAGNETON 

Bt J. KUNZ 

AsMciate Profesaor of Mathematical Physics, Uniyersity of Illinois 

The ferromagnetic crystals, which have been investigated so far, are 
pyrhotite Fe? Sg, apparently hexagonal; magnetite Fes O4, of the cubical 
system; iron crystals of the cubical system; and hematite, FcaOs, 
rhombohedric and hemihedric. The majority of investigations are 
due to P. Weiss and his coworkers. 

The simplest phenomena are offered by Pyrhotite, which has first 
been investigated by P. Weiss,^ and whose studies were continued 
by J. Eunz' and by M. Ziegler.' 

The methods of investigation are essentiaUy the same in all measure- 
ments; they have been partly introduced and widely perfected by P. 
Weiss and his students: they are either methods of deflection, or bal- 
listic methods. The three dimensional problem is reduced to a two 
dimensional one by cutting thin plates from a crystal, parallel to a 
certain crystal surface. These plates, in horizontal or vertical position, 
moveable round about a vertical axis, are placed in a magnetic field of 
given direction and magnitude. If the plate is placed horizontally, the 
deviation D gives the component In of magnetization perpendicular to 
the direction of the horizontal magnetic field H, according to the for- 
mula: 

D-VXHXI«, 

where V is the volmne of the plate. If the magnetic field is turned 
round about the crystal plate, we find readily the normal component 
of magnetization for the various directions of the crystal plate. 

In order to determine the component Ip parallel to the field, we 
suspend the same plate in a vertical position, so that the field falls in 
the surface of the plate, which is at rest, R. If we now rotate the field 
by a small angle a to the right or to the left, the plate will be subject 
to a moment of force 

D>=IpV. HBin(a-/3). 

The plate itself rotates by a small angle fi. If, moreover, the plate 
has a component of magnetization Is perpendicular to the plane of the 

> p. Weifls, Lea propii^tte magn^tiques de la pyrrhotine. Journal de phy9%qu€t 1906, 
p. 469. 

> P. Weifls and J. Euns, /. d. Phy., 1905. p. 847. 

* Max Ziegler. Kristall Magnetische Eigenaohaften dea PyrrhotinB. Diasertation 
ZOrich, 1916. 



\ 



166 THEORIES OF MAGNETIC CRYSTALS AND MAGNETON: KUNZ 

plate, it win make a contribution 1$ cos (a—fi) to the moment. In 
order to reduce this part to a minimum, we choee the plates as thin as 
possible. In the case of the normal pyrhotite the magnetic plane facili- 
tates essentially the measurements. Morever, the demagnetizing 
action of the plates can be neglected in many cases, so that the external 
6eld may be used directly as magnetizing field. Because of the correc- 
tions P and Is this method is cumbersome and is often replaced by the 
ballistic method. A primary coil produces a uniform magnetic field in 
which is placed a secondary coil, S, connected with a ballistic galvan- 
ometer. A ballistic deflection arises when the crystalline plate is intro- 
duced or withdrawn from the secondary cofl, expressed by: 

edt-GIp,V, 

where G is a constant, e the induced e.mi. At the same time, with the 
normal component, we can determine the hysteresis of rotation, by turn- 
ing the field first in one, and then in the opposite direction roimd about 
the plate suspended in a horizontal plane. The apparatus required 
has been perfected and described by Weiss and his students (for instance, 
in the thesis of V. Quittner and Earl Beck.) 

We proceed to the results obtained with the various crystals, among 
which the normal pyrhotite is distinguished by the possession of a 
magnetic plane and rather simple magnetic properties. 

PYRHOTITE 

The chemical composition corresponds approximately to FerSi; 
it crystallizes apparently in the hexagonal system, and its magnetic 
properties correspond at most to the rhombic system. 

A. Streng^ made in 1882 the important discovery of the magnetic 
plane of the pyrhotite, at least for the permanent magnetism. These 
measurements were made complete by Abt' and later by the detailed 
measurements of Weiss, and Weiss and Eunz. We must distinguish 
between two t3rpes of pyrhotite: the crystals from Morro-Velho in 
Brazil, without cleavage> and with uneven fracture. The magnetic 
properties are very simple. Weiss calls these crystals normal pyrhotites. 
The abnormal pyrhotites are widely spread; leaf -like; with badly defined 
magnetic properties; and with great thermomagnetic irregularities, 
especially with respect to hysteresis. 

The plane of base of the normal pyrhotite is the magnetic plane, in 
which the crystal is much easier magnetizable than in the perpendicular 
direction. The magnetic properties repeat themselves three times in 

1 A. strong. Neu€9 Jahthuek der Mintraioaie, 1, p. 185. 1882. 
> Abt. ITftfdemann'c AnnaUn, 1896, p. 135. 



THEORIES OF MAGNETIC CRYSTALS AND MAGNETON: KUNZ 167 

angular distances of 60^ in the magnetic plane, but in various magni- 
tudes. It looks as if the crystals were made up of three elementary 
crystals (crystal components) placed side by side so that the magnetic 
planes are parallel to each other and that the directions of easy magneti- 
zation are inclined mutually by 60^. In order to obtain the properties of 
the simple or elementary cr3rstal, we have to correct the measurements 
by a graphical method of successive approximation. We chose such 
samples in which one of the components predominates strongly. For 
the purified crystal a curve arises of rhombic symmetry, where every 
elementary crystal plate shows a distinguished direction, in which 
saturation is reached by very weak fields; while in the perpendicular 
direction up to 13400 Gauss are required for saturation to take place. 

MEASUREMENTS AT ORDINARY TEMPERATURES 

Fig. 1 gives the curves of the couple in the magnetic plane for 5550 
Gauss. I represents the component In of magnetization perpendicular 




1. Principal Component. (100%). 

2. Second Component. (14.1%). 

3. Third ComponeAt (2.5%). 

Fio. 1 

to the field. Fig. 2 gives In for the various directions and dif* 
ferent fields. Fig. 3 gives the corresponding components Ip parallel 
to the field. In passes twice through zero in the interval 
from 0....180°, while Ip in the same interval shows only maxima 
and minima; this is a common property of the two components for all 
plates of all crystals. It is easy to construct the resultant I by means 
of the two components. The result is shown in Fig. 4. If the 
end point of the vector H covers the whole magnetic plane, the end 
point of I, the resultant magnetization, remains within a certain circle 
which Weiss called the circle of magnetization. If the vector H of the 
field rotates with constant velocity round about the point O, then, 



168 THEORIES OP MAGNETIC CRYSTALS AND MAGNETON: KUNZ 




Fio.a 



^^ 


r 


v 


f 


/'H'^/eaacPa^ss 


^-/y* '¥000 


// 


»?-//« 7J/0 


// 


^'N'/Z/^O 


a 



Fio. S 



starting from the direction 
of easy magnetization Ox, 
the vector I of magnetiza- 
tion foUowB at firat veiy 
slowly the field ; its end point 
remains on the circle of mag- 
netization mitil H has nearly 
reached the direction Oy 
of diflScult magnetization. 
Then I leaves the circle of 
magnetization and curves 
rapidly on a flat curve be- 
hind the field, in order to 
reach it in the direction Oy. 
The larger the magnetic 
field, the more the curve of 
magnetization will approach 
the circle of saturation. For 
sufficiently high fields (13400 
Gauss) the circle of satura- 
tion will be described by I 
with sufficient approxima- 



THSORIBS OP MAGNETIC CRYSTALS AND MAGNETON: KUNZi IW 



tion. (Between 30^ and 
60^ deviations of about 
1% occur). P. Weias 
assumes that for an in- 
finitely large, perfectly 
homogeneous crystal 
in the direction of easy 
magnetization Ox satura- 
tion is reached even in 
the weakest magnetic 
fields; in the other two 
principal directions the 
same would occur, if 
there would not exist an 
internal demagnetizing 
field of magnitude N I, 
where N is a constant 
coefficient. 




A-H«<1992 GauBB, B-H«<4000 Gauss 

G-H»7310 Gauss, D-H-10275 Gauss 

£-H» 11140 Gauss 

FiQ.4 



HYPOTHESIS OF WEISS 

Intrinsic Molecular Field Hi 

In order to represent the properties so far described of the normal 
pyrhotite to a first approximation, P. Weiss makes the following assump- 
tion: in the directions of the three principal axes of the crystal there 
exists an intrinsic molecular field proportional to I in that direction 
and proportional to a certain coefficient having a special value for each 
axis. With respect to the sum of the external and the molecular mag- 
netic fields H the crystal behaves like an isotropic medium. Let 
X| Y, Z be the three perpendicular principal axes of the crystal, H, the 
external field, with the components Hx, H„ H., the intensity of magneti- 
zation I with the components I,, I„ lai the constant coefficients of the 
molecular field Ni, Ns, Ns respectively; then the components of the 
molecular field are equal to: 

H,„=NiI,; H^ = N,I^, H^-N,I.. 

In general the molecular field has not the direction of I, except in the 
direction of the three axes. The resultant components of the magnetic 
force are equal to: 



H,+Nil,; H,-hN,Iy, H.-hN,I.. 



170 THEORIES OF MAGNETIC CRYSTALS AND MAGNETON: KUNZ 



If in a certain direction the resultant magnetic force coincides with the 
resultant intensity I of magnetization, the following equations will hold: 



(1) 



H,+Ni I. _ Hy+Nt I, _ H5+ N, I. _ 
. n, 

J.X Xy X, 



where n is the reciprocal value of the susceptibility of the crystal which 
is isotropic with respect to the total field. It foUows immediately: 



(2) 



Ix- 



Hx 



n-Ni 



I, 



H, 



n-Nt 



I.= 



H. 



n-N, 



— — » — ' — ^are the susceptibilities in the direction of the three 

n— Ni n— Nj n— Nj 

axes with respect to the external field alone. Ni, Ni, N« are considered 

as constants, while n must be considered as function of the sum of the 

external and the internal field; for sufficiently weak fields n is constant; 

therefore the curves of magnetization, according to (2), in the direction 

of the 3 axes for small fields, are straight lines through the origin ot the 

system of coordinates; the curve of saturation I=Ia is a line parallel to 

the axis of H, and one straight line goes over into the other by a cotain 

curve. If the magnetization is restricted to the plane xy, then we have: 



'3) 

or, considering Fig. 5: 



H,+Nil, Hy+N« ly 
I« " ly ' 



H cos a+I Ni cos ^ H sin a+Ni I sin ^ 



Icos ^ 



Isin ^ 




or 



Fig. 6 



I H sin (a-^) = (Ni-N,) 
P sin ^ cos ^: 

or 

H sin (a— ^) = N I sin ^ 
cos ^ 

if weputNi-Ni=N. The 
independence of the coeffi- 
cient Ni— Ni of the mag- 



netic field can be tested in the following way according to Weiss. 



THBORIBS OP MAGNETIC CRYSTALS AND MAGNETON: KUNZ 171 

H,=H,-H, tan /3-H,-H.??-I,(l.^-5?^, 

ar, by means of (3): 

H^«(Ni-N,)I^. 

Hence I, aa function of H<| is a straight line, passing through the origin. 
For saturation we have : 

I«(Ni-N,) = 7200. 

In large fields the agreement is good; in weak fields deviations from 
the straight lines occur, which are not yet explained. N^ecting these 
snliall deviations we may state: the crystal destroys a component H^ of 
the field proportional to I,; the remaining component Hj is proportional 
to the magnetization (and parallel) to I. 

If for smallest fields saturation shall be obtained in the direction Ox of 

easy magnetization, then _^ must be equal to oo, or n— Ni=0. 

In the other two principal directions the same would be true, if it were 
not for a demagnetizing field N I. The curve of magnetization in the 
direction x should be a straight line parallel to the axis H; in the 
direction y a straight line inclined toward Hi, and the deviations may 
be explained by a lack of homogeneity of the crystal. This points to 
the necessity in these magnetic measurements of testing at first the 
crystals by the usual crystallQgraphic methods for purity and homo- 
geneity. A physicist and a crystallographer ought to cooperate in 
tiiese investigations. The approximate truth of the theory can be 
tested by the moment of force D. Here also small deviations between 
theory and experiment, amounting to about 3 per cent, occur. 

P. Weiss has given the following interpretation of the law H sin 
(a— «p) — (Ni— NO I sin ^ cos ^. In a state of equilibrium the molecular 
magnets shall be distributed in parallel straight lines within the mag- 
netic plane, so that the crystal presents saturation in the direction x, 
even without an external field. If now under an angle a the field H 
acts, the magnets will turn away from the direction x and assume a 
new position of equilibrium, given through the angle p. We assume 
that the adjacent magnets act in such a way upon each other that 
there results upon a pole in a magnetic force A m cos ^ in a horizontal 
direction, and a force B m sin ^ in a vertical direction. Then the resul- 
tant X component of the magnetizing force will be: 

Hx»H cosa+A^cos <p, 



172 THSORISS OP MAGNETIC CRYSTALS AND MAGNETON: KUNZ 



and: 

H,">H8ina— B^isin ^. 

But the equilibrium requires: 



or: 
or: 
fdien weput: 



H, sin ^""H, ooe ^; 
(H ooe o+A |i ooe ^) sin ^--ooe ^ (H sin a— B /a sin p); 



Hsin (a— ^)BNIsin ^ooe ^ 
(A+B)m-NL (Kg. 6) 




Fig. 6 



HYSTERE