The occasion of its having been erected, is thus stated[357]:--A king of Egypt having turned the course of the Nile, which diffused itself over the sands of Lybia, and the Delta being formed from the mud of its waters, canals were cut to drain Lower Egypt. The monarchs, who till then had resided at Thebes, removed nearer the mouth of the river, to enjoy an air more temperate, and be more ready to defend the entrance of their empire. They founded the city of Memphis, and endeavoured to render it equal to the ancient capital; decorating it with many temples, among which that of Vulcan drew the attention of travellers: its grandeur and sumptuousness of rich ornaments, each excited admiration. Another temple beside the barren plain was dedicated to Serapis, the principal entrance to which had a sphinx avenue. Egypt has always been oppressed with sands, which, accumulating here, half buried some of the sphinxes, and others up to the neck, in the time of Strabo; at present they have disappeared. To prevent this disaster, they built a large mound on the south side, which also served as a barrier against the inundations of the river, and the encroachments of the enemy. The palace of the kings and a fortress built on the mountain, defended it on the west; the Nile on the east; and to the north were the lakes, beyond which were the plain of mummies, and the causeway which led from Busiris to the great pyramids. Thus situated, Memphis commanded the valley of Egypt, and communicated by canals with the lakes Moeris and Mareotis. Its citizens might traverse the kingdom in boats; and it therefore became the centre of wealth, commerce, and arts; where geometry, invented by the Egyptians, flourished. Hither the Greeks came to obtain knowledge, which, carrying into their own country, they brought to perfection. Thebes, and her hundred gates, lay forgotten, and on the hill near Memphis, rose those proud monuments, those superb mausoleums, which alone, of all the Wonders of the World, have braved destructive time, and men still more destructive.