OBJECT OF BOSS'S VOYAGE 49 



tion, undergoing local and transitory as well as periodical 

 changes. Observations, moreover, must extend over a long 

 period. 



The many explorers within the Arctic Circle had recorded 

 much information. Boss himself had found the Northern 

 Magnetic Pole and seen the compass dip vertically to 90°, and 

 Gauss had calculated the Southern Magnetic Pole to lie in 

 72° 35' S., 152° 30' E. But as his materials were imperfect 

 and the position he had calculated for the Northern Pole was 

 3° wrong, he inferred the Southern Pole to be in 66° S. and 

 160° E. His inference required verification. Permanent sta- 

 tions should be established at suitable spots in the Southern 

 hemisphere, where simultaneous observations might be main- 

 tained in connection with the European stations, while the 

 Erehus and Terror acted as floating observatories on their 

 voyage. Besides the hourly records of the three variables 

 every day for three years, on the four * term days * of the 

 European Magnetic Association simultaneous records were 

 to be kept at intervals of not more than five minutes during 

 the twenty-four hours : in fact, on the term day which fell 

 in Tasmania, Eoss and his colleagues took these observations 

 at intervals of two and a half minutes. 



These considerations took shape in a series of resolutions 

 passed by the British Association for the Advancement of 

 Science in 1888. They were pressed upon Lord Melbourne's 

 Government by an influential Committee and strongly supported 

 by the President and Council of the Eoyal Society, to whom 

 they were referred as the acknowledged advisers of Government 

 in matters of science. But it was not till the foreign scientific 

 institutions, led by Humboldt himself at Sabine's suggestion, 

 threw their weight into the scale, pleading for national co- 

 operation in magnetic work where private enterprise was out 

 of the question, and urging the superiority of the British Navy 

 and the unequalled experience of its officers in polar work, that 

 the Government early in 1S39 agreed to fit out the expedition 

 at a cost of £100,000. 



As a result two exploring ships, each with a crew of sixty- 

 four men, were carefully fitted out under the experienced Arctic 



