246 Invention of the Marinefs Cofnpass. 



ferrum est ad zoron, hoc est septentrionalem, et hoc utuntur naut^. 

 Anguhis vero ahus magnetis illi oppositus trahit ad aphron, id est 

 meridionalem : et si approximes ferrum versus angulum zoron, 

 convertit se ferrum ad zoron, et si ad oppositum angulum ap- 

 proximes, convertit se directe ad aphron." Vincent de Beauvais, 

 a cotemporary of Albertus Magnus, has left a similar passage, 

 likewise quoting Aristotle, in his '■^ Speculum Naturale :'''' "An- 

 gulus quidem ejus cui virtus est attrahendi ferrum, est ad zaron, 

 i. e. septentrionalem, angulus autem oppositus, ad aphron^ i. e. 

 meridiem. Itaque proprietatem habet magnes, quod si approximes 

 ei ferrum ad angulum ipsius qui zaron, i. e. septentrionern respicit, 

 ad septentrionern se convertit, si vero ad angulum oppositum 

 ferrum admoveris, ad aphron, i. e. meridiem se movebit." The 

 names given in these two passages to the north and south pole, 



5<J S Sot 



zoron or zaron, and aphron, are the Arabic ^ — north, and \ — 



south. As to the work here attributed to Aristotle, under the title 

 of a " treatise concerning stones," we have no such Greek text 

 of this author, and it is doubtful if ever he wrote such a book. 

 There is an Arabic treatise entitled l.^g^,^,L.,l i''^^ — the Book of 

 Stones, composed by a certain Lucas, son of Serapion, but pur- 

 porting to be a translation from Aristotle, which Baron De Sacy 

 has shown to be the true source of citations under the name of 

 Aristotle, in the writings of Teifachi and Beilak Kibdjaki ; and 

 very probably Albert and Vincent have quoted this same work 

 in their account of the polarity of the magnet. However, the 

 names zo7'0}i and aphron, applied by these authors to the two 

 magnetic poles, are sufficient to prove that they derived their 

 knowledge of the magnet's polarity from an oriental source. 



But there is no evidence that the Arabs were the inventors of 

 the magnetic needle. It may, indeed, have been in use among 

 the Arabian navigators, before it was noticed by men of science ; 

 but we have in no Arabic work any I'hention of it which goes 

 back beyond the year 1243. In this year, Beilak Kibdjaki made 

 a voyage from Tripoli to Alexandria, and in his treatise entitled 

 __,Lsx=snJ\ Mj.x.^ ^i _jLs\X]^ y^ t_.U:^5 — the Treasure of Mer- 

 chants, touching the knowledge of stones, he has recorded his ob- 

 servations on that occasion, respecting the magnetic needle. " As 

 to the properties of the magnetic needle," he writes, " it is to be 

 observed, that the captains who navigate the sea of Syria, when 

 the night is so obscure that they can see no star by which to steer 



