This natural system was transformed into a highly elaborate man-made
system of basins, dykes, outlets and canals in Pharaonic times. The technology
developed allowed the water to remain in the basins for forty to fifty days
and then to flow back into the Nile or into other basins situated downstream
(see Figure 6.2). The fellaheen sowed into the still-wet soil, and for most of
the crops they cultivated no further irrigation was needed. In certain areas
they applied additional methods of water-lifting with the help of the sakya, a
water wheel (see Illustration 11), the shaduf, a lever, and the tambur, a spiral
pump (Archimedean water screw; see Illustration 10).