Amenemha II. and Sesurtesen II. carried on the campaigns of the first Sesurtesen in the south of Egypt. A monument in the valley of Hamamat exhibits battles with the Punt, _i.e._ with the tribes of the Arabians and the negroes.[160] Sesurtesen III., who succeeded Sesurtesen II., completed the subjugation of Lower Nubia. To protect the new border of the kingdom, he caused fortresses to be erected a little above the falls of the Wadi Halfa, at Semne and Kumne, about 250 miles south of Syene. A pillar discovered in this district has the following inscription:--"Southern border; erected in the eighth year, under the rule of his holiness King Sesurtesen III., who gives life for all eternity. No negro shall pass over it on his way, except the boats laden with the oxen, goats, and asses of the negroes."[161]
The third Sesurtesen was followed by the third Amenemha (2221 to 2179 B.C.). Inscriptions in the Wadi Maghara, in the peninsula of Sinai, tell us that Amenemha III. caused the copper to be conveyed from the mines there by 734 soldiers, in the second year of his reign; and inscriptions in the valley of Hamamat show that the quarries there were frequently used by this king.[162] Near the fortifications of his predecessor, on the rocks of Semne and Kumne, are found numerous records of the height reached by the Nile in the reign of Amenemha III. Here we read--"Level of Hapi (the Nile) in the fourteenth, sixteenth, thirtieth years, &c., under his holiness King Amenemha III., who lives for ever." From these observations we find that the average height of the inundations at that time was more than twenty-four feet higher than at present; and the greatest height reached under Amenemha III. was twenty-seven feet above the greatest height of modern times.[163]
Herodotus tells us the following story;--Among the successors of Menes, Moeris carried out some remarkable works; he built the north gateway in the temple of Hephaestus, excavated a great lake, and erected pyramids in it. "The priests told me that under the rule of Moeris, the Nile overflowed the land below Memphis, although it had only risen to the height of eight cubits, but now the water does not cover the land unless it reaches a height of sixteen or at least fifteen cubits; and it seems to me that if the land were raised again in the same proportion, the Egyptians who live in the Delta below the lake of Moeris would be in distress. The circuit of the lake of Moeris is about 3,600 stades, or sixty schoenes, and the depth in the deepest place about fifty fathoms. The lake extends from north to south. That it was the work of human hands, is clear from the nature of it. About the middle are two pyramids, each of which rises about fifty fathoms out of the water, and on each is a stone colossus seated on a throne. The water of the lake does not arise from springs, for the whole district there is entirely without water, it is introduced by a canal from the Nile. For six months the water flows from the Nile into the lake, and again for six months from the lake into the Nile. While it runs out the fishery brings in a talent of silver a day for the King's treasury; but when the water flows into the lake the product is a third of a talent only.[164]"