As the climate is exceedingly dry, irrigation became as early as the
second dynasty (about 4514 B. C.) an object of national importance. All
through the ages can be marked the tireless persistence and mechanical
ingenuity employed in the problems of irrigation. During the nineteenth
century, Mehemet Ali Pasha began a gigantic system of canals and locks
and weirs. A French engineer of great ability, Mougel Bey, was employed
to carry out this difficult task; his great barrage across the Nile, at
the apex of the delta, is still a very impressive work; unfortunately
the system was a failure. Later British engineers undertook the
management of irrigation, and in 1902 the Nile dam, at the head of the
first cataract above Assuan, was completed. The dam is such a height
that the beautiful temples on the islet of Philæ are partially
submerged; and during several months of the year the ruins are no longer
visible.