Engineering Wonders of the World
Volume I

THE NILE DAMS AND THE ASSOUAN RESERVOIR. 403 before the end of that season. Sudds were therefore constructed to enclose the central portion, together with the ends of the masonry floors just built. Before completing these cen- tral sudds, provision for the passage of the river was made by cutting the sudds on either side, and allowing the water to flow between the newly-built piers. As the bed of the river within the sudds was nearly always alive with springs, great pumping power was required to keep down the water. At one time during the second season twenty-eight centrifugal steam pumps, capable of removing 73 million gallons of water per day, were at work ; and these, with their boilers, distributed over the work- ings, gave to that distant part of the Nile valley the appearance of a smoky industrial Euro- pean town. Towards the end of the season, when the closing length of the floor was near completion, work was terminated suddenly by the rising Nile, which broke through the sudd early one morning before the day’s labour had begun. The third season opened with attempts to enclose the uncompleted portion of the floor- ing. It was not, however, until sudds, extending all the way from the east bank, and enclosing this gap, had been formed, that success came, and the task of joining up the two ends could be taken in hand. This operation proved very troublesome, owing to the number of springs concentrated in the bed of the river at that part. The junction was eventually made by building in steel rails with the concrete and masonry. Spaces formed by springs washing out the sand from beneath Fig.- 24.—WATER PASSING THROUGH SLUICES OF ASSOUAN DAM.