DEPARTMENT OF TERRESTRIAL MAGNETISM. 299 



December 31, 1913, being about 100,000 miles. A specially designed 

 office and laboratory building, containing 44 rooms, was erected during 

 the period May 1913 to February 1914. Seven new instruments, for 

 use in magnetic surveys at sea and on land, have been designed and 

 chiefly constructed in the Department's own instrument shop; with 

 the methods and appliances introduced, an accuracy has been achieved 

 in ocean work almost comparable with that on land; about 125 articles 

 and publications by various members of the investigational staff have 

 appeared; the magnetic data of interest and importance to mariners 

 have been made known with a promptness heretofore impossible; in 

 fact, the data have usually been available to the leading hydrographic 

 establishments within two to four months after the observations were 

 made at sea.^ A variety of investigations (theoretical, observational, 

 and experimental) have been made, the chief results of which either 

 have already been published, or can be within the next two years; 

 last, but not least, a number of men have now received the requisite 

 training and experience to assure continued successful progress of the 

 work of the Department. 



To bring the preceding summary of work to the date October 31, 

 1914, there should be included the chief operations and results described 

 in the following pages. It must be a matter of congratulation that 

 so much of the magnetic survey work could be completed before 

 the intervening of such serious interruptions as must necessarily follow 

 with a continuance of the inter-European war. 



MAGNETIC SURVEY OF THE OCEANS. 



The circumnavigation cruise of the Carnegie, as already stated in the 

 previous report, was successfully completed with the return of the vessel 

 to Brooklyn on December 19, 1913. During the period February to 

 June 1914, all necessary repairs were made. On June 8, 1914, the 

 Carnegie sailed away again from Brooklyn, on her third cruise, this 

 time in the North Atlantic, and under command of Mr. J. P. Ault^ 

 Mr. Peters having been placed in charge of the important expedition 

 to Hudson Bay mentioned below. 



The Carnegie arrived at Hammerfest, Norway, on July 3, after a 

 very successful trip. The shore and harbor work having been com- 

 pleted, she left Hammerfest on July 25, bound for Reykjavik, Iceland, 

 reaching, during the trip, under sail alone, the remarkably high latitude 

 of 79° 52' north, in the East Greenland Sea and off the northwest coast 



^For example, the values of the magnetic declination observed aboard the Carnegie from Long 

 Island Sound to Hammerfest, June 10 to July 2, 1914, were printed in the issue of the Journal 

 Terrestrial Magnetism, which appeared on September 1, 1914. The values on the portion of the 

 cruise, Hammerfest, Spitzbergen, Iceland, July 26 to August 23, 1914, were received at Wash- 

 ington on September 21, ready to be sent to the printer. 



