THE UNIVERSE. OCEANIC DISCOVERIES. 259 



ment from the instruments used by the pilots of Majorca de- 

 scribed by Raymond Lully ( 404 ) in 1295, in his " Arte de 

 Navegar," to that which Martin Behaim made in 1484 at 

 Lisbon, and which was perhaps only a simplification of the 

 meteoroscope of his friend Regiomontanus. When the Infante 

 Henry (Duke of Viseo) the great encourager of navigation, 

 and himself a navigator, founded a school of pilots at Sagres, 

 Maestro Jayme of Majorca was named its director. Martin 

 Behaim was desired by king John II. of Portugal to compute 

 tables for the sun's declination, and to instruct pilots to 

 " navigate by the altitudes of the sun and stars." Whether 

 the log line, which makes it possible to estimate the length 

 of the course passed over, whilst the direction is given by the 

 compass, was known as early as the end of the fifteenth 

 century, cannot be determined, but it is certain that Pigafetta, 

 a companion of Magellan, speaks of the log (la catena a 

 poppa) as of a long known means of measuring the distance 

 passed over. ( 405 ) 



The influence of Arabian civilisation on Spanish and 

 Portuguese navigation, through the astronomical schools of 

 Cordova, Seville, and Granada, is not to be overlooked : the 

 large instruments of Cairo and Bagdad were imitated on a 

 small scale for maritime use. The names were also trans- 

 ferred ; the " astrolabon" which Martin Behaim attached to 

 the main mast belongs originally to Hipparchus. When 

 Yasco de Gama landed on the east coast of Africa, he 

 found the Indian pilots at Melinda acquainted with 

 the use of astrolabes and cross staffs. ( 406 ) Thus, by 

 intercommunication consequent on more extended inter- 

 course between nations, as well as by original inven- 

 tion, and by the mutual aids to advancement furnished by 



