DEPARTMENT OF TERRESTRIAL MAGNETISM. 279 



necessary by the system of Helmholtz-Gaugain coils installed in the observa- 

 tory. The final standardization in intensity for the magnetometers returned 

 by Messrs. Brown and Parkinson included comparisons with C. I. W. sine 

 galvanometer No. 1, thus giving indirectly, through the comparison work at 

 Teddington, England, and at Kakioka, Japan, the relations between the 

 types of electromagnetic instruments of Great Britain, of the Magnetic Survey 

 of Japan, and of the Carnegie Institution of Washington. 



The experimental observatory on the deck of the Laboratory at Washington was 

 continued in operation throughout the year, photographic records of the 

 electric potential-gradient and of the conductivity of the atmosphere being 

 obtained (see p. 273). 



Miscellaneous. — Besides the extensive series of observatory comparisons 

 with the adopted standards of the Department obtained by Mr. Parkinson 

 (see p. 276), comparisons of observatory standards were obtained during 

 the year by other observers of the Department staff at Christchurch, New 

 Zealand; Huancayo, Peru; Melbourne, Australia, and Kakioka, Japan. 



Magnetic and allied observations during the solar eclipse of September 21, 

 1922. — In addition to the special program of observations to be made in 

 connection with this eclipse, which was prepared by Messrs. Bauer and Flem- 

 ing and supplied to expeditions and observatories, the following final arrange- 

 ments were made during the Director's visit to Australia: 



(1) A detailed program of special observations pertaining to terrestrial 

 magnetism and atmospheric electricity at the Department's magnetic obser- 

 vatory, Watheroo, Western Australia, this station being south of the belt 

 of totality. 



(2) Special magnetic observations, chiefly of the magnetic declination, at 

 stations within the belt of totality, namely, at Wallal, Western Australia, by 

 Mr. Hargreaves from England, who will be stationed at the same place where 

 the Lick Observatory party, under the direction of Dr. Campbell, will be 

 located; at Cordillo Downs, South Australia, by Professor Kerr Grant of the 

 University of Adelaide, and by Mr. A. L. Kennedy, chief assistant of the 

 Adelaide Observatory (this station will be where Professor Dodwell, govern- 

 ment astronomer of South Australia, will be making his astronomical observa- 

 tions); at Coongoola, Queensland, Australia, by Observer D. G. Coleman, 

 of the Department of Terrestrial Magnetism. It is expected that the astro- 

 nomical party of Victoria under the direction of Dr. J. M. Baldwin, and that 

 of New South Wales under the direction of Professor Cooke, will be located 

 at Goondiwindi, Queensland, and that, time and personnel permitting, special 

 magnetic observations will be made. 



Information has been received that other institutions and observatories 

 will arrange for special observations in accordance with our published program. 



INSTRUMENT WORK AND BUILDINGS. 1 



Classification of work. — The larger part of the work done in the instrument- 

 shop during the year was devoted to the design and construction of new 

 instruments and apparatus. About one-quarter of the time was given to 

 the design and development of experimental apparatus for the different 

 divisions and sections. The remaining time was about equally divided 

 between improvements and repairs of instruments and buildings, and mis- 

 cellaneous work and stock. 



» From the reports of the assistant director, J. A. Fleming, and of the foreman of the instrument- 

 shop, C. Huff. 



