630 COSMOS. 



mariner and a successful propagator of Christianity. In his 

 book entitled Fenix de las maravillas del orbe, and published 

 in 1286, Lully remarks, that the seamen of his time employed 

 " instruments of measurement, sea charts, and the magnetic 

 needle."* The early voyages of the Catalans to the north 

 coast of Scotland and the western shores of tropical Africa 

 (Don Jayme Ferrer reaching the mouth of the Rio de Ouro, in 

 the month of August 1367), and the discovery of the Azores 

 (the Bracir Islands, on the Atlas of Picigano, 1367) by the 

 Northmen, remind us that the open western ocean was navi- 

 gated long before the time of Columbus. The voyages prose- 

 cuted under the Roman dominion in the Indian Ocean, 

 between Ocelis and the coasts of Malabar, in reliance on the 

 regularity of the direction of the winds,f were now conducted 

 by the guidance of the magnetic needle. 



The application of astronomy to navigation was prepared 

 by the influence exercised in Italy, from the thirteenth to the 

 fifteenth centuries, by Andalone del Nero and John Bianchini, 

 the corrector of the Alphonsine tables, and in Germany by 

 Nicolaus de Cusa,;j; George von Peuerbach, and Regiomontanus. 

 Astrolabes designed for the determination of time and of 

 geographical latitudes by meridian altitudes, and capable of 

 being employed at sea, underwent gradual improvement from 

 the time that the astrolabium of the Majorcan pilots was in 

 use, which is described by Raymond Lully, in 1295, in 



* " Tenian los mareantes instrumento, carta, compas y aguja." Sala- 

 zar, Discurso sobre los progresos de la Hydrografia en Espaha, 1809, 

 p. 7. 



t See p. 538. 



J Regarding Cusa (Nicolaus of Cuss, properly of Cues, on the Moselle), 

 see p. 469, and also Clemens' treatise, Ueber Giordano Bruno und 

 Nicolaus de Cusa, s. 97. where there is given an important fragment, 

 written by Cusa's own hand, and discovered only three years since, 

 respecting a threefold movement of the earth. (Compare also Chasles, 

 Aperfu sur Vorigine des methodes en Geometrie, 1807, p. 529.) 



Navarrete, Dissertation historica sobre la parte que tuvieron los 

 Espanoles en las guerrasde Ultramar 6 de las Cruzadas, 1816. p. 100; 

 and Examen crit., t. i. pp. 274-277. An important improvement in 

 observation by the use of the plummet, has been ascribed to George von 

 Peuerbach, the instructor of Regiomontanus. The plummet had, how- 

 ever, long been employed by the Arabs, as we learn from Abul-Hassan- 

 Ali's description of astronomical instruments, written in the thirteenth 

 century. SMillot, Traite des instrumens astronomiques des Arabed r 

 1835, p 379; 1841- p. 205. 



