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.[1] 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."[2]
Speed of ancient ships. A few notices remain to us of the time occupied in the performance of different voyages by ancient vessels, from which we may deduce the general fact, that though owing to their construction—being generally from three to four times as long as they were broad, with shallow keels, and rarely other than square sails—they could not have made much way
