For millennia, Egypt has depended upon the waters of the Nile. Its annual floods fertilize the land. By the time Britain extends its dominion over Egypt, the Cairo Barrage is the key to control, its name taken from the French term meaning a dam or irrigation channel designed to increase a river's depth or to divert its flow. An attempt to blow up the Manufiyah regulator in the Barrage is not a petty matter. Gareth Owen, The Mamur Zapt, Chief...