compass, or of any instrument by which the bearings of the different headlands could have been determined, they might, having found their latitude, have depended, as mariners in modern times have been often obliged to depend, with some confidence upon their dead-reckoning. The wonder is that they should ever have ceased to hug the land, and that they really ventured on the long voyages they unquestionably accomplished. [Sidenote: Mariner’s compass.] Some writers have attempted to show that the Arabians and the Chinese were acquainted with the mariner’s compass even in those remote ages; but for this idea there does not seem to be any warrant whatever. Certain it is that Marco Polo, who made voyages on the Chinese seas in native boats, nowhere alludes to it; while Niccola de’ Conti, who navigated the Indian waters in an Indian vessel, in 1420, after the properties of the magnet were known in Italy, expressly states that the mariners had no compass, but were guided by the stars of the Southern Pole, the elevation of which they knew how to measure. Nor is there any reason to believe that the Chinese had any greater knowledge, though there may be in some Chinese books a notice of the physical fact that, by constant hammering, an iron rod becomes magnetized—in other words, has imparted to it the property of pointing to the north and to the south. Such a discovery, so important for purposes of navigation, would at once have been recognised, and could not have been kept secret for ten centuries. Moreover, there is really abundant evidence to show that the compass had been long in use among the nations of the West before it was adopted by the Chinese; Dr. Robertson having justly remarked that in Arabic, Turkish, and Persian, there is not only no original word for it, but that the name they give it is the Italian _bossolo_: nay, further, that the Arabians have nowhere recorded any observation by them of the variation of the needle.[53] We may add that Dr. Robertson’s view is completely confirmed by Sir John Chardin, one of the most learned of Eastern travellers, who made special inquiries on this subject. “I have sailed,” says he, “from the Indies to Persia in Indian ships when no European has been on board but myself. The pilots were all Indians, and they used the forestaff and quadrant for their observations. These instruments they have from us, and made by our artists, and they do not in the least vary from ours, except that the characters are Arabic.”[54] [Sidenote: Speed of ancient ships.]