DEPARTMENT OF TERRESTRIAL MAGNETISM. 325 



SOUTH AMERICA, 



Field work in Brazil was carried on by Observer D. W. Berky. 

 Leaving Washington on March 5, he arrived at Rio de Janeiro on 

 March 23. Several days were spent in comparing his instruments with 

 those of the magnetic observatory at Vassoiiras, near Rio de Janeiro. 

 In addition, the Department's station of 1912 at Rio de Janeiro was 

 reoccupied. Preparations were then made for an extensive trip of about 

 2,500 miles through Central Brazil. Starting from Rio de Janeiro on 

 April 8, the first stage of the journey was by rail to Catalao, then by 

 mule caravan to Goyaz and Leopoldina, the party arriving at the latter 

 place on May 25. Eight magnetic stations were established on the 

 way. Four additional stations were made during a short trip up 

 the Araguaya River in a small boat as far as Registro, which was 

 reached June 8. On the next day the descent of the Araguaya River 

 was begun. Leopoldina was again reached on June 12 and on June 14 

 the descent was resumed to Concessao, where the party arrived on 

 July 8. Leaving again on July 14, in company with Mr. Luis Antonio 

 do Cruz, a rubber trader, who had a well-manned barge, Alcobaca was 

 reached on August 18, after encountering numerous rapids, shoalings, 

 and portages. Travel was resumed on August 22 by steamer down 

 the Tocantins River to Para, which was reached on August 30. Upon 

 completion of observations at our previous station, Pinheiro, Mr. Berky 

 returned to Washington on September 22. The magnetic elements 

 were determined at 41 stations in all, and valuable geographical data 

 were obtained in a comparatively little known part of Brazil. 



MISCELLANEOUS. 



Observer E. Kidson, from August to October 31, 1915, was engaged 

 on comparisons of our magnetic standards with those in use at the 

 magnetic observatories in Great Britain. 



The Director made a preUminary examination on July 27-28 of the 

 suitability of the region around Pikes Peak, Colorado, for investigating 

 the important question as to change of magnetic elements with altitude 

 and the suitability of Pikes Peak for a mountain magnetic observatory. 



DETAILS OF INVESTIGATIONAL WORK. 



A general account is given on pages 315-317 of the various researches 

 under this head. A fuller statement respecting some of the chief 

 investigations is contained in the following abstracts of published 

 articles and papers presented before scientific societies, and reports of 

 progress : 



Magnetic declinations and chart corrections obtained by the Carnegie from Brooklj-^n, New 

 York, to Colon, Panama, March 1915, and from Balboa, Canal Zone, to Honolulu, 

 Hawaii, March-May 1915. J. P. Ault. Terr. Mag., vol. 20, 69-70 (June 1915). 



Magnetic declinations and chart corrections obtained by the Carnegie from Honolulu, 

 Hawaii, to Dutch Harbor, Alaska, June-July 1915. J. P. Ault. Terr. Mag., 

 vol. 20, 104 (September 1915). 



