Until quite recently, one of the perennial problems of life in the Middle East was the lifting of water from rivers and wells for irrigation. Near the Nile and other large rivers, annual floods naturally watered a thin strip of land along sloping banks. Using a seed drill known as a seluka, the inhabitants of the Nile valley were able to farm the inundated areas. But these narrow bands of fertility, often only a few yards wide, could not sustain even a sparse population. Hence, in ancient times, numerous irrigation methods were developed to extend cultivation.
No doubt one of the first of these practices was the carrying of earthen jars or animal skins, filled with water, from the source to the place of use. But even with draft animals and slave labor, such a method could hardly have been expected to water a field regularly and properly. Therefore, a seesaw-like contrivance called the shadoof was invented. Operated by one man with the benefit of a counterweight, it could lift twenty to thirty cubic meters of water a day, enough to irrigate about one acre. Backbreaking though it was, the shadoof was the only major water-lifting machine for centuries. Then, during the Hellenistic era, two new devices were developed. One of them was the cylindrical Archimedean screw, which saved labor but also could not irrigate much more than an acre. The other was the saqiya.
Although some history books record the saqiya as the Persian waterwheel, and its origins have been linked with Mesopotamia, its principal area of use was and is the Nile Valley. Conducting a survey in the rural northern region of the Sudan, I was able to find only a handful of the eleven thousand wheels registered there forty years ago. But seeing these few was like unearthing a lost world; they were exactly like those known by the Ptolemies.
In its oldest and simplest form, the saqiya consists of a huge wooden wheel with wooden cogs on its outer rim, a similar but smaller wheel, and a large open-spoked wheel with a wide, open periphery. The large wheel is fastened onto a vertical wooden axle. An arm is mounted on the upper part of this shaft, so that the wheel can be turned by a cow, a pair of donkeys, or even a camel. Some of the bigger wheels require a pair of bulls or water buffaloes. Usually a seat is attached to the arm so that a small child can sit and drive the animals. As the larger wheel is turned, the smaller wheel, which is mounted on a horizontal axle, is driven as a gear. This second axle runs under the platform on which the saqiya is erected so that it does not interfere with the circular path of the draft animals. On the end of the horizontal axle opposite the smaller wheel is the open-spoked wheel on which large earthenware jars known as zears or qadus are attached. If the river level is high, these jars may lashed directly onto the wheel. On the other hand, if the water is low, the jars may be tied to two parallel loops of rope that are jointed together by spacing bars. This rig works like a pulley; the jars fill as they drop into the water and the endless ropes go around the bottom of their reach. When they are lifted over the open-spoked wheel, they spill the water through the open periphery into a trough that leads to the field channels.
The music of the saqiya
No description of the saqiya would be complete without relating the sounds that emanate from the device. The mechanism itself has a creaking groan that is
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