PHYSICAL FEATURES. xxm 
part of its extent, in the month of May, practically destitute of vegetation ; but Grant 
saw a few birds and two kinds of lizards, and from the circumstance that the ground 
was full of burrows of small rodents, the probability is that this plain after rain is 
not the absolute atmur that Grant supposed it to be. 
After the route has surmounted the escarpments, it traverses the elevated plateau of 
Nubian sandstone, and crosses a succession of rocky ridges running parallel with 
others rising from 122 to 304 metres above the valley, traverses khors, some of them 
covered with drifted sands, and finally over rocky ground to the wells of Murat in the 
crystalline mountain known as Jebel Raft, the plateau at this part having an elevation 
of about 517 metres above the sea. This mountain, as originally pointed out by 
Linant de Bellefonds, is the site of ancient gold-workings. It is cut up by many 
ravines, the drainage from which passes through the valley in which the wells are found, 
and empties itself into the Wadi Kabkaba, which, in its turn, joins the Wadi Allaki. 
In all of these ravines water is found after rain, and, in the Wadi Suffur, the last- 
mentioned traveller, in the month of September, met with beautiful green mimosas in 
flower. Like other mountains to the east, Jebel Raft has not a few natural reservoirs of 
water in its ravines. There is also a valley distinguished by the presence of some dhum- 
palms, distinct from the true dhum-palm of Upper Nubia, and seemingly characteristic 
of other depressions of the Nubian desert ; and associated with these in the bottom of 
the valley there are a few acacias. It is thus evident that whenever there are groups 
of mountains of crystalline rocks in this desert, their raviDes and wadis always contain 
a certain amount of vegetation dependent on the rare rainfall, the water of which 
percolates clown into the beds of the valleys and into the wells, and fills the natural 
reservoirs, which are evidently as numerous in the crystalline mountains of this part of 
the desert as they are in those to the east. The mountains, however, being lower, and 
far removed from the influence of the Red Sea, the rainfall is much less. Major 
Lyons 1 mentions that from November 1891 to August 1896 only a few showers fell, 
but that on these two dates the amount of rain was sufficient to fill the wells in the 
neighbourhood of Murat. Beyond these wells, wadis and rocky ridges are crossed, 
and that remarkable expanse of desert sand, the Bahr-Hud-Ab, strewn with spheroidal 
stones of all sizes up to the size of shot, is traversed, after which the sandy Bahr 
Belaama, with its isolated conical rocks about 76 metres in height, and its old well 
in the bed of the valley, conducts the traveller to a gap in the escarpment of the 
high plateau of Nubian sandstone, through which a gradual descent is made to 
Korosko. A few acacias are passed on the way, but vegetation throughout is 
extremely scant. 
Linant de Bellefonds's 2 detailed account of the region intervening between Assuan 
and the Elba group of mountains is of extreme interest. Some distance beyond 
1 Quart. Journ. Geo]. Soc. liii. 1S97, p. 360. 
2 L'Etbaye, 1828. 
