CH. VIII. FOVAGES ROUND THE WORLD. 57 



had long been known that the needle did not point due 

 north, but a little to the east of the north. Columbus, how- 

 ever, found that, as he went westward, the needle gradually 

 lost its eastward direction, and pointed due north, and then 

 gradually went a little way to the west. It remained like 

 this till, on his return, he came back to the same place where 

 it had changed, and then it passed gradually back to its first 

 position. From this he learnt that, although the magnetic 

 needle always points towards the north, it varies a little in 

 different parts of the world. The reason of this is not even 

 now clearly understood, and we must content ourselves here 

 with knowing that it is so. 



The next grand voyage of discovery was made by Vasco 

 de Gama, a Portuguese, who set sail July 9, 1497, to try 

 whether it was possible to sail round the south of Africa. 

 He succeeded, and during the voyage he could not help 

 remarking the new constellations or groups of stars, never 

 seen in Portugal, which appeared in the heavens. This 

 proved to him that the earth must certainly be a globe, for if 

 you were to sail for ever round a flat surface, you would 

 always have the same stars above your head. 



At last there came a third discoverer, Ferdinand Magellan 

 (or Magalhaens), of Spain, who set off August 10, 15 19, deter- 

 mined to sail right round the world. He steered westward 

 to South America, and discovered the Straits which separate 

 Terra del Fuego from the mainland, and which were called 

 after him the Straits of Magellan. Then he sailed north- 

 wards, across the equator again, till he came to the Ladrone 

 Islands, where he was killed fighting a battle to help the 

 native king. Sebastian del Cano, his lieutenant, then took 

 the command of the ship, which arrived safely back in the 

 port of St Lucar, near Seville in Spain, on September 7, 



