'River Nile at High Flood', Egypt, 1926.
© Science Museum / Science & Society Picture Library
One of a series of three maps showing the Aswan Dam acros the Nile in Egypt. Built between 1898 and 1902, the Aswan Dam was designed to better control the masive annual Nile floods for irrigation as well as providing the posibility of hydro-electric power for industry. After the dam was completed, it became clear that its height and the size of the reservoir behind it were insufficient. As a result, the dam's height was further raised in 1907-1912 and again in 1929-1934. Even after this the dam ultimately proved inadequate for its purpose, leading to the building of the much larger Aswan High Dam between 1960 and 1970.