THE GIFT OF THE NILE Egypt is readily recognizable on the map today as an angular wedge of northeastern Africa and a chunk of southwestern Asia. It covers slightly more than a million square kilometers, and at the beginning of the twenty-first century it was inhabited by approximately seventy-five million people. The capital of Egypt, Cairo, with its population of more than sixteen million, is the largest city on the African continent. But to envision Egypt historically, and to understand its geographical essence, one must think first about the Nile, the longest river in the world, and a river that flows through the Sahara, the largest desert in the world. When the Greek traveler Herodotus described Egypt as the gift of the Nile in the fifth century BC, he was probably just repeating what was already a well-worn phrase, but one true since long before historical memory and no less so now. Rainfall is insignificant in the valley of the Nile, and not abundant in the Delta, so that virtually all of Egypt's water comes from the Nile, and even with the amazing development during the past few decades of the Mediterranean and Red Sea coasts, 95 percent of the population of Egypt still live within a few miles of the river. Almost all of Egypt's arable land, about 34,000 square kilometers, lies in the river valley and the Delta. The Egyptian Nile has three major sources. The longest is the White Nile. The sources of this river, until the mid-nineteenth century one of the world's great geographical mysteries, lie deep within Africa, especially in the lake region, where Lake Victoria in Uganda and Tanzania makes the largest contribution. As it flows for more than 6,400 kilometers to the Mediterranean, the White Nile passes through ten modern nations amid changing geography. In southern Sudan, it becomes mired in the Sudd, a vast swamp that slows it and causes heavy water loss through evaporation, although the Sudd also mediates the river's flow, releasing it over a longer period of time. Because of the Sudd and the fact that Lake Victoria's catchment area is fed by rainfall throughout the year, the Egyptian Nile's flow never fails entirely. The other main sources of the Egyptian Nile are the Blue Nile, which joins the White Nile in Sudan at Khartoum, and the Atbara, which flows into the Nile farther north in Sudan. They account for the annual inundation of the Nile, the central geographical feature of Egyptian history. Their tributaries are rooted in the Ethiopian highlands, where the summer monsoon dumps vast amounts of water that runs off quickly, laden with silt and clay washed away from Ethiopia's volcanic mountains. Although popular imagination tends to associate the sources of the Nile with the White Nile and the lake region of central Africa, 84 percent of the river's water that reaches Egypt comes from Ethiopia. In perfect harmony with the solar year, the Nile began to rise in Egypt at the midsummer solstice and peaked at the autumnal equinox, rising from a low of less than fifty million cubic meters per day in early June to over seven hundred at the inundation's height in September. When the swollen river reached the broad flood plains of Egypt, it spilled over its banks, soaking the rich alluvial soil and washing away the harmful salts that were the long-term bane of other ancient hydraulic civilizations such as Mesopotamia. As it receded, the river left behind pools of water and a fine layer of sediments and minerals. The drying earth would crack open, aerating the soil and thus completing the cycle of renewal. The shift to the past tense is because the construction of the Aswan High Dam ended the inundations in Egypt during the 1960s. The inundation was the pulsing life force of Egypt. Everything depended on it--and that it be at the correct level. If the inundation was too low, or if it failed entirely, the fields could not be irrigated adequately. A succession of low Niles was catast Excerpted from A History of Egypt: From Earliest Times to the Present by Jason Thompson All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.