with the exception of the lowest,
which is named Lokoli, where faint eddies mark the place of the more
dangerous reefs; and were it not that the fall here is rather more
pronounced and the current somewhat stronger, few would suspect the
existence of a cataract at the spot. As the waters go down, however, the
channels gradually reappear. When the river is at its lowest, the three
westernmost channels dry up almost completely, leaving nothing but a
series of shallow pools; those on the east still maintain their flow,
but only one of them, that between the islands of Tombos and Abadin,
remains navigable. Here Thutmosis built, under invocation of the gods of
Heliopolis, one of those brickwork citadels, with its rectangular keep,
which set at nought all the efforts and all the military science of the
Ethiopians: attached to it was a harbour, where each vessel on its way
downstream put in for the purpose of hiring a pilot.*

The monarchs of the XIIth and XIIIth dynasties had raised fortifications
at the approaches to Wady Haifa, and their engineers skilfully chose the
sites so as completely to protect from the ravages of the Nubian pirates
that part of the Nile which lay between Wady Haifa and Philse.*

* The foundation of this fortress is indicated in an
emphatic manner in the Tombos inscription: "The masters of
the Great Castle (the gods of Heliopolis) have made a
fortress for the soldiers of the king, which the nine
peoples of Nubia combined could not carry by storm, for,
like a young panther before a bull which lowers its head,
the souls of his Majesty have blinded them with
fear." Quarries of considerable size, where Cailliaud
imagined he could distinguish an overturned colossus, show
the importance which the establishment had attained in
ancient times; the ruins of the town cover a fairly large
area near the modern village of Kerman.

Henceforward the garrison at Tombos was able to defend the mighty curve
described by the river through the desert of Mahas, together with the
island of Argo, and the confines of Dongola. The distance between Thebes
and this southern frontier was a long one, and communication was slow
during the winter months, when the subsidence of the waters had rendered
the task of navigation difficult for the Egyptian ships. The king
was obliged, besides, to concentrate his attention mainly on Asiatic
affairs, and was no longer able to watc