102 THE INTELLECTUAL RISE IN ELECTRICITY. 



sight of shore. They were built 1 of wood of so hard a 

 quality that it was liable to split or crack like earthenware, 

 so that nails, even if they had been available, could not be 

 driven into it. The planks, after being bored, were 

 fastened to the stem and stern posts by wooden pins, and 

 were then bound together with ropes made from the 

 fibrous husk of the cocoanut, the cocoa fiber or coir of the 

 present time. Marco Polo, 2 after describing these boats, 

 says that they u are of the worst kind and dangerous for 

 navigation, exposing the merchants and others who make 

 use of them to great hazards." Being unfit to venture 

 upon the open sea, these vessels were of necessity kept near 

 land. Hence they were constantly exposed to danger from 

 reefs and shoals, and especially from such currents as the 

 Arabian Nights story-teller mentions, w 7 hich swept them 

 irresistibly upon the rocks, so that it might easily seem 

 that the ships were dragged to the latter by some myster- 

 ious attractive force. A few tales of shipwreck of that sort 

 were easily elucidated by simply picking out from Pliny's 

 Natural History (which the world implicitly relied upon 

 for centuries) a convenient explanation. The story of 

 Magnes furnished one which fitted neatly to the facts, 

 and the tropical imagination of the Orient needed no ac- 

 cess of fervor to add the flying forth of the nails like birds, 

 and the breaking of the ill-fated ship into a thousand 

 pieces. 3 



We have now to return to the study of the world's pro- 

 gress in knowledge of magnetic polarity. We have exam- 

 ined, briefly, the reasons which render the claim of origi- 

 nation of the mariner's compass by the Chinese as one to 



J The Three Voyages of Vasco da Gama. Hakluyt. Soc. London, 1869, 

 240. 



2 Travels of Marco Polo. London, 1854, 20-21. 



'See Thevet: Cosmog. Univ., p. 445. Azuni : Dissert, sur la Boussole 

 (cit. sup.) 



