The dam has been constructed of granite ashlar taken from quarries near Aswan. These quarries are the very same from which the ancient obelisks were hewn. The amount of rock used was about one million tons in weight. In building the dam it was found to be very difficult to lay the foundation, since the bottom of the river proved to be unsound, although in the preliminary reports it had been declared to be of solid granite. In some instances it was found necessary to dig down for forty feet, in order to lay a perfectly secure foundation on which the heavy wall could be superimposed. This required much additional labour, and great risk and damage was encountered during the progress of the work at the date of the impending rise of the waters of the Nile. Rubble dams were raised to ward off the waters from the point where it was necessary to excavate. The holes were gradually filled with solid blocks of granite; then the base of the structure, one hundred feet in width, was laid, and the massive piers, capable of resisting the immense pressure of the water during the height of the floods, were raised, and the whole edifice was at length completed with great rapidity by the aid of many thousand workmen, just before the rise in the Nile occurred. The official opening of the dam took place on the 10th of December, 1902. The dam at Aswan is the greatest irrigation project ever yet undertaken, but is by no means the last one likely to be executed in relation to the waters of the Nile. A smaller dam is to be constructed at Assiut, in order to supply a system of irrigation in the neighbourhood of that city, and also to carry water across to thousands of acres between this region and Cairo. This project is planned somewhat after the design of the barrage which is below Cairo. It is impossible to forecast what engineering skill may have in store for the future of Egypt. One may hope, at least, that the most prosperous days of the Pharaohs, the Ptolemies, and the Romans will be reproduced once more for the modern Egyptians, as an outcome of the wise administration which has originated through the occupation of the country by the English, as an international trust held for civilisation. By aid of British initiative, Egypt now controls a vast empire in equatorial Africa and the Sudan, and the great water ways of this immense territory are being gradually brought under such control that the maximum advantage to all the population will be the necessary result. The whole Nile is now opened to commerce. The British have guaranteed equal rights, and what has been called the policy of the "open door," for the commerce of all nations.