In comparison with the vast epochs of which we treat how near to us are Nineveh, Babylon, and Carthage! Yet the very sites of the former two have become uncertain, and of the last we only know by the presence of the few scattered ruins on the shores of the Mediterranean Sea. Tyre, the vast entrepôt of commerce in the days of Solomon, was stated, rightly or wrongly, by Benjamin of Tudela, to be but barely discernible (in 1173) in ruins beneath the waves; and the glory of the world, the temple of King Solomon, was represented at the same date by two copper columns which had been carried off and preserved in Rome. It is needless to quote the cases of Persia, Greece, and Rome, and of many once famous cities, which have dissolved in ruin; except as assisting to point the moral that conquest, which is always recurring, means to a great extent obliteration, the victor having no sympathy with the preservation of the time-honoured relics of the vanquished. When decay and neglect are once initiated, the hand of man largely assists the ravages of time. The peasant carts the marbles of an emperor's palace to his lime-kiln,[90] or an Egyptian monarch strips the casing of a pyramid[91] to furnish the material for a royal residence. Nor is it beyond the limits of possibility that the arrogant caprice of some, perhaps Mongol, invader in the future, may level the imperishable pyramids themselves for the purpose of constructing some defensive work, or the gratification of an inordinate vanity. In later dates how many comfortable modern residences have been erected from the pillage of mediæval abbey, keep, or castle? and how many fair cities[92] must have fallen to decay, in Central and Eastern Asia, and how many numerous populations dwindled to insignificance since the days when Ghenghis and Timour led forth their conquering hordes, and Nadun could raise four hundred thousand horsemen[93] to contest the victory with Kublai Khan. The unconscious ploughman in Britain has for centuries guided his share above the remains of Roman villas, and the inhabitants of the later city of Hissarlik were probably as ignorant that a series of lost and buried cities lay below them, as they would have been incredulous that within a thousand years their own existence would have passed from the memory of man, and their re-discovery been due only to the tentative researches of an enthusiastic admirer of Homer. Men live by books and bards longer than by the works of their hands, and impalpable tradition often survives the material vehicle which was destined to perpetuate it. The name of Priam was still a household word when the site of his palace had been long forgotten. The vaster a city is, the more likely is it to be constructed upon the site of its own grave, or, in other words, to occupy the broad valley of some important river beneath whose gravels it is destined to be buried.