De Lussac had explained to O’Connelly, in detail, how his theory was built around the existence of a system of huge underground cisterns in the bedrock beneath the Haram esh-Sharif in Jerusalem, the site of the most holy of Muslim mosques. The only detailed study ever carried out had been made in the 19th century by the British Palestinian Survey Fund. De Lussac had studied the topographical contours and elevations of the bedrock traced by the 19th century engineers observing the Temple Mount sloped from north to south, between two enclosed valleys, the Kedron Valley to the east, and the Tyropean Valley to the west.
At its summit, to the north, at a height of 743 metres, stands the Masjid Qubbat As-Sakhrah - the Dome of the Rock. The hill was thus protected to the east, west and south by steep slopes. To the north of the Dome of the Rock was a relatively deep transversal depression. These feature therefore formed a natural defence.
It was on this spot that the Citadel of the Hasmoneans was built, which much later became the Citadel of Antonia, built by Herod, and finally the Haram esh-Sharif, where the Jews believe their Temple had once stood.
The City of David stood on a small hill just to the south of the Temple Mount and was supplied with water from the Gihon Spring that was diverted by a tunnel to flow into the Siloam Pool, providing the city with water in the case of siege.
As the city grew an additional supply of water, both for the population and its animals, was necessary and reservoirs were built to the north, the Struthon Pool and the Sheep’s Pool connected to the city by aqueducts. However, water could not be brought up to the ancient citadel.
Today the citadel is the Haram, a rectangular platform, partly natural and partly man-made, built around the hill that served as its foundation. The walls that can be seen surround the hill and the space inside, between the sloping surface of the natural rock and the vertical ramparts, was filled in with earth and rubble to form a horizontal platform, level with the summit of the now hidden hill. Therefore the upper layer of the Haram was made up of earth, rubble and mezzeh – a kind of fossilised clay that is not impermeable and could not have been used for cisterns or conduits.
Beneath the upper layer is an intermediary bed of rock, called Malachite, this is impermeable and is between twenty and thirty metres thick, descending from the summit with a slope of 15° to a depth of about forty metres relative to the Haram’s surface, reappearing downhill and outside of the ramparts. Below this is another impermeable layer of rock, called Dolomite. The cisterns were mostly built in the Malachite layer of rock. These cisterns were rediscovered and explored by the 19th century archaeologists and the engineers of the Palestinian Survey Fund, who recorded their details and measurements together with those of the different interconnecting channels and conduits.
The most ancient cisterns were built in the form of an amphora and later, in Roman times, the form of became more rectilinear. Openings situated at ground level could be used as well shafts or channels to collect rainwater whilst others were used as water supply conduits or access for maintenance. In the same manner stairways were progressively built into the rock to facilitate access for workers during the construction of the cistern. These stairways could later constitute passage ways for drawing water or for the adjustment of weirs and other arrangements installed to control the flow of water as well as for maintenance of the installations. Certain older cisterns were later enlarged and transformed by masonry works.
The aqueduct supplying water from the Etam Spring was directly connected into five underground cisterns situated at the southern extremity of the bedrock. These five cisterns held a total of almost thirty million litres of water.
De Lussac therefore concluded that the Temple must have been situated downstream of the underground cisterns on the principal that the water could not have been brought up to the level of the Haram in sufficient quantities by hand – noting that the pulley was invented by Archytas between 460 and 365BC, half a millennium after Solomon – thus positioning the site below the Triple Gate beneath the southern rampart of the Haram, where he theorised water could gush out at the greatest possible pressure onto the Temple’s platform.
During Herod’s reign and the reconstruction of the second Temple, the whole of the city’s water supply system was reorganised and improved with the help of Roman technology and Marcus Vipsanius Agrippa the son-in-law of the Roman Emperor.
5
An Outline
then even a piglet shines and even a sow wears silk