The very district of Goshen in which they settled was occupied again, shortly after their desertion of it, by nomads from Edom who had besought the Pharaoh for meadow-land on which to feed their flocks.

The need of pasturage from time immemorial has urged the pastoral tribes of the desert towards the fertile land of the Nile.

When want of rain has brought drought upon Canaan, parching the grass and destroying the corn, the nomad has invariably set his face toward the country which is dependent for its fertility, not upon the rains of heaven, but upon the annual overflow of its river.

It was a famine in Canaan, produced by the absence of rain, which made Jacob and his sons "go down into Egypt." But besides this immediate cause there was yet another.

They were assured of a welcome in the kingdom of the Nile and the gift of a district in which they might live.