On February 20,1898, the khedive approved of a contract with Messrs. John Aird and Company, which settled the much-debated question of the Nile reservoir and the scheme for the great dam at Aswan. The government was able to start the undertaking without any preliminary outlay. It was agreed that the company should receive the sum of $800,000 a year for a period of thirty years. Aswan, six hundred miles south of Cairo, was selected as an advantageous site because the Nile at that place flows over a granite bed, and is shut in on either side by granite rocks, which, when the course of the river is barred, would form the shores of the artificial irrigation lake. Before this work started, there had been a long controversy as to the effect produced by the rising waters upon the renowned temple on the Isle of Philae. Lord Leighton, the president of the Royal Academy, had vigorously protested against allowing the destruction of this famous ancient ruin. In the modification of the plans caused by this protest, it was hoped that no serious harm would result to this well-preserved relic of ancient Egyptian religion and art. [Illustration: 269.jpg APPROACH TO PHILAE] The enterprise was put through with great rapidity, the project fully realising the designs of its inaugurators. By aid of this great structure, 2,500 square miles have been added to the area of the 10,500 miles hitherto subject to cultivation. Its value to the country is at the least worth $100,000,000. The dam extends for one and a quarter miles, and possesses 180 openings, each of which is twenty-three feet high, and will altogether allow the outpour of fifteen thousand tons of water per second. Navigation up and down the Nile has not been impeded, since, by a chain of four locks, vessels are able to pass up and down the river. Each lock is 260 feet long and thirty-two feet wide. During flood-time the gates of the dam are open; while the flood is subsiding the gates are gradually closed, and thus, in a long season of low water, the reservoir is gradually filled up for use through a system of canals, whereby the waters can be drawn off for irrigation and the main flow of the Nile can be increased. The lake thus formed is nearly three times the superficial area of Lake Geneva in Switzerland, and the waters are held back for a distance of 140 miles up the course of the river. The reservoir is filled during the months of January and February, and from April to the end of August the water is let out for irrigation purposes from the bottom of the reservoir, thus enabling the sediment, which is of such value, to be carried out through the sluices. Four or five waterings are allowed to percolate from it to the various regions which are thus brought under cultivation, and besides this the main supply of the river itself is artificially increased at the same time.