Ancient Egypt, an arid waste of desert extending over thou-
THE FERTILE MARGIN sands of square miles, left m a n almost n o w h e r e to live but
along a thin green strip of land w a t e r e d by the N i l e . As the
river flowed f r o m south to n o r t h , f r o m the steep cliffs near
A s w a n to the Delta b e y o n d Cairo, the v e r d a n t strip on each
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