54 TERRESTRIAL MAGNETISM. 



Marco Polo began his travels in 127 1, and returned in 

 ] 295, the evidence of Guyot de Prcvins and Jaques de 

 Yitry shows that the compass was used in European naviga- 

 tion at least sixty or seventy years before the commencement 

 of his travels. The names of Aphron and Zohron, given to 

 the north and south poles of the needle by Vicentius of 

 Beauvais in his "Mirror of Nature" (1254), indicate that 

 Arab pilots were the channel through which the nations of 

 Europe received the Chinese compass, being obviously 

 derived from that learned, ingenious, and active race, 

 traces of whose language are so frequent in our star-maps, 

 though appearing there too often in a mutilated form. 



Prom all these circumstances, there can be no doubt that 

 the general employment of the magnetic needle in ocean 

 navigation by the Europeans from the 12th century, (and 

 in a limited degree probably still earlier), proceeded from 

 the Mediterranean and its shores, and took place chiefly 

 through the agency of Moors, Genoese, Venetians, Major- 

 cans, and Catalans. Catalan sailors, under the conduct of 

 the celebrated navigator, Don Jaime Perrer, advanced in 

 1346 to the mouth of the Bio de Ouro, 23 40' N. latitude, 

 on the west coast of Africa; and from the evidence of 

 Eaymund Lully (in his nautical work, Penix de las Mara- 

 villas del Orbe, 1286), it appears that long before Jaime 

 Perrer, the Barcelonese used sea-charts, astrolabes, and sea- 

 compasses. 



The knowledge of the existence of a greater or less 

 amount of magnetic declination (its early name was simply 

 " variation," without any adjunct) had naturally been 

 also diffused over the Mediterranean, by report from China, 

 through the medium of Indian, Malay, and Arab mariners. 



