Abstract: The preserved heritage of al-Jabin, a town located in Yemen’s western highlands, offers a unique opportunity to document traditional water engineering principles. There are no springs in the immediate vicinity, because the town is perched at the edge of the mountain escarpment. Even today, water is provided by open cisterns that collect surface run-off following a rain. But as the rains needed to feed the system are highly unpredictable, the water supply is never secure. The perimeter wall of one of the cisterns bears a group of seven signs, a detailed description of which is given in Kitab Shams al-Ma`arif wa-Lata’if al-`Awarif, awork attributed to Ahmad ibn `Ali al-Buni (d. 1225), awell-known prolific writer on magic. Al-Buni explains that the signs symbolize God’s supreme name and thus display great magical power of a protective and well-wishing nature. Generally speaking, magical practices attempt to influence the course of natural events by calling upon a superhuman force. In the case of the cistern, God’s supreme name was inscribed in the hopes that this would lead to a guaranteed water supply. While it is easy to dismiss al-Buni’s text and the observed practice in al-Jabin as superstitious frailty, one needs to bear in mind that under life-threatening circumstances, even people in the modern West easily resort to magical procedures.
The town of al-Jabin is positioned on the western escarpment of the Yemeni highlands at an altitude of 2,400 meters (see map, Figure 1). Two rainy seasons occur in spring (between March and April) and in late summer (between July and September); however, these reflect long-term averages and the spatial and temporal variability of rainfall is high from year to year.1 Localized out-of-season rains are nothing unusual, nor are dry years – to the point of no precipitation at all.
The steepness of the mountainsides limits arable farming to human-made terraces. TonyWilkinson, who has studied terraced agriculture in the Yemeni highlands in detail, concluded that its origins go back to at least the third millennium BCE.2 Today, in the area of al-Jabin, the cultivation of perennial coffee bushes produces a valuable cash crop on the western slopes, which face the Red Sea and receive most of the precipitation.
There is a distinct difference between the crops grown on the western mountainsides and those on the terraces of the drier eastern terrain lying in the rain-shadow. Here, sorghum is cultivated as a subsistence crop and provides both cereal grain and animal fodder. Where direct rainfall is not sufficient for terraced agriculture, the farmers harvest rainwater from the adjacent slopes serving as mini-catchments. Diversions are created either by digging ditches (where possible) or, more commonly, by heaping up gravel and stones on the open surface. As soon as it rains, the surface run-off is funnelled by the human-made berms into broader channels that direct the water from the hillsides onto the lower-lying fields.3 In many parts of Yemen, the term used for such human-made diversions is sawaqi (sg. saqiyah), which is why the aforementioned authors refer to rainwater harvesting as “sawaqi supplementary irrigation.”
Since al-Jabin is perched at the escarpment’s edge, with the ground falling away sharply to the west, there are no springs in the immediate vicinity. Spring water for drinking is found only at levels considerably lower down the mountain, and using it involves the labor-intensive task of hauling it in small containers on the backs of people or draught animals. The solution to providing the town with domestic water was to construct open cisterns (birak, sg. birkah) that collect surface run-off following a rain, based on the principles of rainwater harvesting. Al-Jabin has two large public cisterns, one on its north side and one on its south side (Figure 2). The southern one, situated below the military fort, developed a crack years ago and, despite an attempt to mend it, remains largely empty; the northern one is fully functional. Both cisterns are roughly oval in shape and have several rows of high ledges and a broad staircase leading to the bottom. Many steps have between one and three small raised pods at roughly half a step in height. This provides easy access for water collection at all times, no matter what the depth of the water level during the course of a year. The cisterns were lined with qadad, the traditional Yemeni lime plaster applied to a building’s external and internal facades predominantly as a protective coating for waterproofing.
The Bayt al-Shaykh Cistern and the Group of Seven Signs
Bayt al-Shaykh is a cluster of dwellings located in al-Jabin’s southern part, next to the Grand Mosque. The buildings are centered around a small cistern that is exclusive to the settlement (Figure 3). Access to it is provided by an underground passage that also connects the houses to each other. Such tight clusters of dwellings, often built wall-to-wall to give a fortress-like impression, are typical of the al-Jabin area.4 The houses usually share a mosque and a cistern. In the example of Bayt al-Shaykh, part of the Grand Mosque’s roofs actually serve as collection surfaces for rainwater to feed the settlement’s cistern. In turn, any overflow from that cistern is used in a small pool that is part of the mosque complex.
On the plaster surface of the Bayt al-Shaykh cistern’s perimeter wall, which is partly formed by the immediately adjacent houses, is an inscription together with a group of seven signs (Figure 4, below). Ahmad ibn `Ali al-Buni (d. 1225), a prolific writer on magic, described these signs. The main work attributed to him is Kitab Shams al-Ma`arif wa-Lata’if al-`Awarif. It is assumed, however, that major parts of the book were only written at the beginning of the fourteenth century by a group of authors, for which stylistic reasons can be cited, as well as the fact that the textmentions individuals who lived after al-Buni’s death.5 For the purposes of this article, the question of authorship and exact date are not significant. The work and al-Buni, both of which enjoy great popularity in the Middle East even today, are considered authoritative on magic, and the fact that students would add to a great scholar’s writings under his name, instead of their own, has a long tradition in the Islamic world.
This work appears in three redactions: Shams al-Ma`arif, a short one that is the earliest version; Shams al-Ma`arif al-Wusta, one of medium length; and Shams al-Ma`arif al-Kubra, a long version that is the most recent and remains very popular in the Middle East.6 In the short redaction, Shams al-Ma`arif, al-Buni describes the seven signs as follows7:
… three sticks lined up after a seal; at their head, something that is like the bent head of a lance; a mim squashed and amputated; then a ladder
which leads to every hoped-for object but which is nonetheless not a ladder; four objects resembling fingers have been lined up, pointing towards good things but [they are] without a fist; a ha’ in half; then a waw bent over like a tube of a cupper, but which is not a cupping glass.
He then sums up their meaning:
…this is the name which is supreme in its power, and if you did not know this before, know it [now] ... Here is the name ofAllah, may His glory be exalted ...
The signs found on the Bayt al-Shaykh cistern follow al-Buni’s description closely, but with the three vertical lines lacking the wavy horizontal line on top, the letter waw resembling more closely a mim, and the order of the waw and the ha’ reversed. Of course, Arabic inscriptions in general are known for their rather liberal use of letter shapes and even the order of whole words. As for the seven signs in particular, differences of shape and order were a familiar phenomenon until al-Buni’s time, after which only minor variations occur.8