granite, limestone,—­in spite of their enormous size, or of the strengthening of their foundations by a bed of sand and by three or four courses of carefully adjusted blocks to form a substructure, the Nile was ever threatening them, and secretly working at their destruction.  Its waters, filtering through the soil, were perpetually in contact with the lower courses of these buildings, and kept the foundations of the walls and the bases of the columns constantly damp:  the saltpetre which the waters had dissolved in their passage, crystallising on the limestone, would corrode and undermine everything, if precautions were not taken.  When the inundation was over, the subsidence of the water which impregnated the subsoil caused in course of time settlements in the most solid foundations:  the walls, disturbed by the unequal sinking of the ground, got out of the perpendicular and cracked; this shifting displaced the architraves which held the columns together, and the stone slabs which formed the roof.  These disturbances, aggravated from year to year, were sufficient, if not at once remedied, to entail the fall of the portions attacked; in addition to this, the Nile, having threatened the part below with destruction, often hastened by direct attacks the work of ruin, which otherwise proceeded slowly.  A breach in the embankments protecting the town or the temple allowed its waters to rush violently through, and thus to effect large gaps in the decaying walls, completing the overthrow of the columns and wrecking the entrance halls and secret chambers by the fall of the roofs.  At the time when Egypt came under the rule of the XIIth dynasty there were but few cities which did not contain some ruined or dilapidated sanctuary.  Amenemhait I., although fully occupied in reducing the power of the feudal lords, restored; the temples as far as he was able, and his successors pushed forward the work vigorously for nearly two centuries.

The Delta profited greatly by this activity in building.  The monuments there had suffered more than anywhere else:  fated to bear the first shock of foreign invasion, and transformed into fortresses while the towns in which they were situated were besieged, they have been captured again and again by assault, broken down by attacking engines, and dismantled by all the conquerors of Egypt, from the Assyrians to the Arabs and the Turks.  The fellahin in their neighbourhood have for centuries come to them to obtain limestone to burn in their kilns, or to use them as a quarry for sandstone or granite for the doorways of their houses, or for the thresholds of their mosques.  Not only have they been ruined, but the remains of their ruins have, as it were, melted away and almost entirely disappeared in the course of ages.  And yet, wherever excavations have been made among these remains which have suffered such deplorable ill-treatment, colossi and inscriptions commemorating the Pharaohs of the XIIth dynasty have been brought to light.