“From Goz Regeb to a point on the river west of Kassala the country inland consists of, first, a broad strip of cotton soil, sparsely sprinkled with small trees and bushes. To the east of this there occurs a stretch of more or less sandy soil, supporting a coarse grass and a few stunted isolated trees until the fertile soil adjoining the Khor El Gash is reached.
“This khor, after passing the town of Kassala and receiving numerous small khors from the east, conveys its flood water in a more or less defined channel, or in some places channels, as far as Filik. Along its banks, north of Kassala, dom palms are replaced by thick tamarisk or tarfa trees, which continue most of the way to Filik, on nearing which they in turn are replaced by talh and other thick thorn scrub.
“A short distance north of Filik, owing to the extreme flatness of the country, the eastern channel disappears, and the water dissipates itself through the soil to a distance varying according to the volume of the flood water, its direction being roughly N.N.W.
“The opinion, still held by some, that the Gash water flows towards the Langeb seems untenable.
“The Odi plain which receives numerous small khors from the eastern hills is probably about the same level as the Gash plain, but there certainly appears to be sufficiently rising ground between, though hardly noticeable, to preclude the Gash reaching Odi.
“From Filik, following the direction of the Gash, the bushes which define its course gradually decrease until they become as scattered as in the rest of the plain, and all trace of its direction is lost.
“The plain still extends northwards, until at a point, said to be not far from Jebel Safra, it receives the waters from the Angwatiri and Godamaieb khors, which join here, and probably that of other khors flowing in a south-westerly direction from the rocky hills to the north-east. From these hills also many khors start in an easterly and south-easterly direction, which finally reach the Odi or the Langeb.
“From J. Sanai northwards, for some distance the country consists of large ranges of hills, separated by wide valleys, containing very often stretches of cotton soil in the wider parts, but close to the hills the ground becomes rocky and stony.
“From these valleys, the khors, some of which are lined with dom palms, trend in a south-westerly direction, but in nearly every case are hemmed in by sand hills, and are thus prevented from reaching the Atbara. The valleys, or rather basins, where the final exit is stopped, being usually selected by the Arabs to cultivate.
“Of these valleys the principal are Hegerib, Todabanob, and Hambokeb.