232 CARNEGIE INSTITUTION OF WASHINGTON. 



previously studied, it has been possible, through the kindness of the Western 

 Electric Company and the Bureau of Standards, to investigate the behavior 

 of the iron-nickel alloy known as permalloy, remarkable for its great sus- 

 ceptibility in weak fields, and the iron-cobalt alloy introduced by Preuss, 

 remarkable for its great induction in intense fields. In both substances the 

 elementary magnets have, at least approximately, the same ratio of angular 

 momentum to magnetic moment as those of the other ferromagnetic sub- 

 stances investigated. The kindness of the Bureau of Standards and the 

 Westinghouse Electric and Manufacturing Company has also made it possible 

 to prepare rotors of the purest iron, of a cobalt-nickel alloy, and of an addi- 

 tional alloy of nickel and iron. It is expected that observations on these 

 substances will be made soon. The work has been very greatly facilitated 

 by the kindness of the Capital Traction Company, which in February sub- 

 stituted bus service for the part of its night street-car service inaugurated in 

 December on the Chevy Chase line. 



Miscellaneous Laboratory Work. — Mr, Kotterman has devoted most of his 

 time to assistance in the work on magnetization by rotation. He further 

 developed for the Division of Observational and Administrative Work the 

 technique and apparatus for making fine quartz fibers and prepared, as the 

 result of his experience in the past few years, notes on the production of 

 quartz fibers (see abstract on pp. 260-261). He also designed several appli- 

 ances for special photographic work at the laboratory and installed them 

 after they were constructed in the shop; these have improved greatly the 

 facilities for preparing illustrations for reports on investigations. Detailed 

 memoranda and instructions for the use of the new photographic equipment 

 were prepared by him. 



Publications. — In the Philosophical Magazine for December 1922, Dr. 

 Barnett published a paper on "Electric fields due to the motion of constant 

 electromagnetic systems," containing the greater part of the material on 

 electromagnetic induction abstracted on pages 285 to 289 of last year's 

 report. He also published a paper on "Magnetization, rotation, and atomic 

 structure" in the Physikalische Zeitschrift for January 1, 1923 (see abstract, 

 pp. 247-248). Mr. Kotterman prepared a description of an automatic 

 focusing enlarger, designed and constructed by him, which was published 

 in Photo-Miniature for May 1923 (see abstract, p, 260). 



EXPERIMENTAL WORK IN TERRESTRIAL ELECTRICITY,^ 



Atmospheric-electric apparatus and instructions for observatories and special 

 expeditions. — Conductivity recording apparatus No, 7 for the Huancayo 

 Magnetic Observatory was assembled and tested in the Laboratory at Wash- 

 ington prior to its shipment to the observatory. The details of this work were 

 attended to chiefly by Mr. W. C. Parkinson (who later installed the apparatus 

 at Huancayo) and by Mr. H. F. Johnston. 



Equipment and instructions were prepared for the atmospheric-electric 

 work of the MacMillan North Greenland expedition of 1923 to 1924. The 

 same equipment was provided as used in the MacMillan Baffin Land expe- 

 dition of 1921 to 1922, but both the apparatus and the procedure were 

 somewhat modified in accordance with experience gained on the previous 

 expedition. Similarly, in the matter of equipment and procedure for the 



^ From the report of the chief of the section, S. J. Mauchly. 



