the earliest settlements in Egypt, but without success. The infiltration
of water had made excavation impossible and had no doubt destroyed
everything belonging to the most ancient settlement. It is not going too
far to predict that exactly the same thing will be found by any explorer
who tries to discover a Neolithic stratum beneath a city-mound of
Babylonia. There is little hope that prehistoric Chaldæa will ever be
known to us. But in Egypt the conditions are different. The Delta is
like Babylonia, it is true; but in the Upper Nile valley the river flows
down with but a thin border of alluvial land on either side, through the
rocky and hilly desert, the dry Sahara, where rain falls but once in two
or three years. Antiquities buried in this soil in the most remote
ages are preserved intact as they were first interred, until the modern
investigator comes along to look for them. And it is on the desert
margin of the valley that the remains of prehistoric Egypt have been
found. That is the reason for their perfect preservation till our own
day, and why we know prehistoric Egypt so well.

The chief work of Egyptian civilization was the proper irrigation of
the alluvial soil, the turning of marsh into cultivated fields, and the
reclamation of land from the desert for the purposes of agriculture.
Owing to the rainless character of the country, the only means
of obtaining water for the crops is by irrigation, and where the
fertilizing Nile water cannot be taken by means of canals, there
cultivation ends and the desert begins. Before Egyptian civilization,
properly so called, began, the valley was a great marsh through which
the Nile found its way north to the sea. The half-savage, stone-using
ancestors of the civilized Egyptians hunted wild fowl, crocodiles,
and hippopotami in the marshy valley; but except in a few isolated
settlements on convenient mounds here and there (the forerunners of the
later villages), they did not live there. Their settlements were on