had been accustomed to steer a direct course instead of following the coast line, or if they had been acquainted with the properties of the 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.
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
