THE UNIVERSE. OCEANIC DISCOVERIES. 279 



the writings of Columbus, contains views of physical geo- 

 graphy, remarks on the influence of geographical longitude, 

 on the declination of the magnetic needle, on the inflection 

 of the isothermal lines between the west coast of the old 

 and the east coast of the new Continent, on the situation of 

 the great Sargasso bank in the basin of the Atlantic, and on 

 the relations of this part of the ocean to the atmosphere 

 above it. Erroneous observations ( 43 ) in the neighbourhood 

 of the Azores on the position of the Pole star had misled 

 Columbus as early as the period of his first voyage, from the 

 deficiency of his mathematical knowledge, to entertain the 

 belief of an irregularity in the spherical form of the earth. 

 According to his view, the earth was protuberant in the 

 western hemisphere, so that the ships gradually arrived 

 nearer to the sky on approaching the line (raya) where the 

 magnetic needle points to the true north ; and this elevation 

 he supposed to be the cause of the cooler temperature. The 

 solemn reception of the Admiral at Barcelona took place in 

 April 1493, and on the 4th of May of the same year Pope 

 Alexander VI. signed the celebrated bull which " establishes 

 for ever" the demarcation line ( 431 ) between the Spanish and 

 Portuguese possessions at a hundred miles westward of the 

 Azores. If we bear in mind that Columbus, immediately 

 after his return from his first voyage of discovery, purposed 

 to go himself to Rome, in order, as he said, " to report to 

 the Pope all that he had discovered," and if we remember 

 the importance which the cotemporaries of Columbus attached 

 to the line of no variation, it may be admitted that there 

 are grounds for a suggestion first put forward by myself, 

 that at the moment of his highest court favour Columbus 



