Egypt was the scene of the earliest of all advances in engineering science.  The system of irrigation, which originated in the days of the oldest Egyptian dynasties, has remained practically the same through all the intervening centuries until very recent times.  During every period of vigorous government the rulers of Egypt paid special attention to irrigation canals and sluices, through which the flood waters could be brought to some hitherto uncultivated area.  The famous barrage, projected early in the nineteenth century and only rendered efficient for what it was intended since the British occupation, made very little alteration in the actual supply of water during the seasons of low water in the Nile.  The most serious problem is how to ward off the periodical famine years, of which there has been record from the earliest ages, and of which the Book of Genesis has left an account in the history of Joseph and the seven years of plenty and seven years of famine.  Without creating such a vast reservoir in the upper waters of the Nile, that the storage there retained can be available in years of low water to fill the river to its accustomed level, it is impossible to prevent the calamity occasioned by leaving many districts of Egypt without cultivation for one or more seasons.  With the desire of accomplishing this, Sir Benjamin Baker, the leading authority on engineering works in Egypt, prepared a scheme for reserving a vast storage of water in Upper Egypt at Aswan.  It was also decided to follow up the enterprise with another to be undertaken at Assiut.

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]