TERRESTRIAL MAGNETISM — BAUER. 27 I 



The work under this head has been greatly facilitated by the special 

 arrangements made at the instance of the late Secretary of State, Mr. 

 John Hay, respecting free entry of the magnetic instruments in 

 foreign ports and the soliciting of the special cooperation of consular 

 and diplomatic officers. 



In connection with the land and sea work it has become essential 

 to make some experimental investigations at Washington with the 

 special view of ascertaining the cause of outstanding instrumental 

 differences, the reliability in the application of corrections derived 

 by comparison, and the changes in the corrections for any par- 

 ticular set of instruments when used in various magnetic latitudes. 

 These studies have an important bearing upon the inter-comparison 

 and reduction of observatory standards, as well as the standardiza- 

 tion and testing of instruments designed for field use. 



C. Eclipse Work. 



In response to the appeal of the department and in accordance 

 with the program of proposed work published in various journals 

 for simultaneous magnetic and allied observations during the total 

 solar eclipse of August 30 last, cooperative work was conducted at 

 stations distributed over the entire belt of totality, even'- civilized 

 nation participating. 



The supplementary stations finally decided upon by the depart- 

 ment in order to still further provide for the proper distribution and 

 successful study of the subject under investigation were as follows : 



Labrador : Battle Harbor (magnetograph, atmospheric electricity 

 observations, and declination eye-readings, the whole under the direc- 

 tion of Mr. J. E. Burbank, assisted by Messrs. Bowen and Homrig- 

 haus) and Turnavik (magnetic declination eye-readings by Mr. G. L. 

 Hosmer, of the Massachusetts Institute of Technology). Both parties 

 were supplied with full sets of absolute instruments, with which 

 important magnetic secular variation and magnetic distribution data 

 were obtained en route and returning. As the Canadian magnetic 

 expedition, under the direction of Professor Stupart, located its station 

 in Labrador within the belt of totality, the above stations were selected 

 so as to have one immediately south of the belt and the other about 

 the same distance north. Dr. W. G. Cady, of the Wesleyan Uni- 

 versity, also made magnetic observations at Black Point, Nova Scotia, 

 and Dr. L,. A. Bauer, assisted by Prof. W. C. Bauer, of Baker Uni- 

 versity, observed at Missinaibi, Ontario, Canada. 



In addition, Professors Elster, Geitel, and Dr. Harms successfully 

 made special atmospheric electricity observations at Palma, Majorca. 



