FOREWORD 



The Carnegie — the world's only sea-going non-magnetic ob- 

 servatory — was constructed by the Carnegie Institution of Wash- 

 ington to obtain geophysical data over the oceans. This vessel 

 was part of the equipment of the Institution's Department of 

 Terrestrial Magnetism, founded April 1, 1904, realizing a plan 

 for an international magnetic bureau submitted by Dr. Louis A. 

 Bauer, the Department's director from 1904 and its director 

 emeritus from 1930. The purpose of the Department, set forth 

 in the plan, is "to investigate such problems of world-wide interest 

 as relate to the magnetic and electric condition of the Earth and 

 its atmosphere, not specifically the subject of inquiry of any one 

 country, but of international concern and benefit." Among the 

 problems proposed was the magnetic survey of ocean-areas and 

 magnetically unexplored regions, so that more accurate and 

 comprehensive charts might be constructed. It was in the 

 realization of this part of the plan that the Carnegie did such useful 

 service during 1909 to 1929. The first six cruises were made 

 almost exclusively for the surveys of the Earth's magnetism and 

 electricity for which she was designed. The seventh cruise was 

 to be unique in the vessel's history, as its program contemplated 

 besides these survey-operations extensive researches in oceanog- 

 raphy, including the exploration of the ocean-depths for the 

 physical, chemical, and biological conditions found there. 



In May 1928 the Carnegie left the United States for a three- 

 year cruise of all oceans — the seventh since her launching in 1909 

 — to further increase the store of geophysical data. Captain 

 James Percy Ault, and the staff under his command, had com- 

 pleted one year and a half of this voyage when disaster struck 

 suddenly. The ship and its unique equipment — evolved in 

 twenty-five years of active endeavor of the Department — were 

 totally destroyed, and the Captain lost his life together with the 

 Cabin-Boy. The tragedy took place November 29, 1929, at 



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