[Illustration:  Fig. 48.—­Section of dike at Wady Gerraweh.]

In order to reach the diorite and grey granite quarries of the Hammamat Valley, the Pharaohs caused a series of rock-cut cisterns to be constructed along the line of route.  Some few insignificant springs, skilfully conducted into these reservoirs, made it possible to plant workmen’s villages in the neighbourhood of the quarries, and also near the emerald mines on the borders of the Red Sea.  Hundreds of hired labourers, slaves, and condemned criminals here led a wretched existence under the rule of some eight or ten overseers, and the brutal surveillance of a company of Libyan or negro mercenary troops.  The least political disturbance in Egypt, an unsuccessful campaign, or any untoward incident of a troubled reign, sufficed to break up the precarious stability of these remote establishments.  The Bedawin at once attacked the colony; the workmen deserted; the guards, weary of exile, hastened back to the valley of the Nile, and all was at a standstill.

The choicest materials, as diorite, basalt, black granite, porphyry, and red and yellow breccia, which are only found in the desert, were rarely used for architectural purposes.  In order to procure them, it was necessary to organise regular expeditions of soldiers and workmen; therefore they were reserved for sarcophagi and important works of art.  Those quarries which supplied building materials for temples and funerary monuments, such as limestone, sandstone, alabaster, and red granite, were all found in the Nile valley, and were, therefore, easy of access.  When the vein which it was intended to work traversed the lower strata of the rock, the miners excavated chambers and passages, which were often prolonged to a considerable distance.  Square pillars, left standing at intervals, supported the superincumbent mass, while tablets sculptured in the most conspicuous places commemorated the kings and engineers who began or continued the work.  Several exhausted or abandoned quarries have been transformed into votive chapels; as, for instance, the Speos Artemidos, which was consecrated by Hatshepsut, Thothmes III. and Seti I. to the local goddess Pakhet.[9]

[Illustration:  Fig. 49.—­Quarries of Silsilis.]

[Illustration:  Fig. 50.—­Draught of Hathor capital in quarry of Gebel Abufeydeh.]

The most important limestone quarries are at Turah and Massarah, nearly opposite Memphis.  This stone lends itself admirably to the most delicate touches of the chisel, hardens when exposed to the air, and acquires a creamy tone most restful to the eye.  Hence it was much in request by architects and sculptors.  The most extensive sandstone formations are at Silsilis (fig. 49).  Here the cliffs were quarried from above, and under the open sky.  Clean cut and absolutely vertical, they rise to a height of from forty to fifty feet, sometimes presenting a smooth surface from top to bottom, and sometimes cut in stages