THE 
GHOLOGICAL MAGAZINE. 
NENV SERIES. DECADE NV. "VOIR. Vill. 
No. IX.—SEPTEMBER, 1910. 
ORIGINAL ARTICLIEHS. 
I.—Txe Orticin or tHE Nite VaLiey In Ecyrt. 
By W. F. Hume, D.Sc., F.R.S.E., A.R.S.M., F.G.S., Director of the Geological 
Survey of Egypt. 
f{\HE article which appeared by Dr. Ball in the Februarynumber of the 
GuorocicaL Macazine (pp. 71-6), strongly urging the origin of the 
Eeyptian Nile Valley as due to erosion rather than faulting, is the first 
public expression of a widespread feeling that the familiar rift theory 
is based on comparatively feeble foundations, and either requires 
strengthening or withdrawal. It must be remembered that when 
the Geological Survey of Egypt commenced its operations in 1896 the 
relation of deep African depressions to rifts was an accepted theory 
which had been found applicable in a number of striking instances. 
As one who has studied portions of the Nile Valley and the 
neighbouring deserts of Egypt for some years, I submit these few 
remarks, adopting a somewhat more personal point of view than is 
usual in papers of this nature, not from a desire for controversy, but 
because the subject is one worthy of discussion. 
During 1896 I was in frequent correspondence with Mr. Barron 
regarding Egyptian geology, and from his letters it was evident that 
two points had impressed him, viz. the absence of sand-deposits in 
the Eastern Desert and the abundant evidence of faulting. The 
widespread nature of these fractures seemed to me open to some 
doubt, but the first year’s work in the Eastern Desert (1897-8) led 
me in the main to adopt Mr. Barron’s views. The magnificent 
dislocations in the hills opposite Qena, and gigantic slip-faulting of 
Arras and Abu Had, north-east of that town, were too apparent to 
escape even superficial observation, and the discovery of the faulted 
areas described by Fraas, Barron, and myself near Qosseir, helped 
materially to strengthen the view that faults played an important 
part in the structure of the country. 
The investigations of 1898-9 in Sinai only tended to enhance their 
significance, and in a paper on the ‘‘ Rift Valleys of Eastern Sinai” 
I pointed out that a series of parallel valleys with the younger strata 
faulted between the older formations could only be explained as due 
to fractures arranged on some systematic basis. An attempt was also 
made to widen this conception so as to embrace the Gulf of Suez, 
Nile Valley, etc. 
DECADE V.—VOL. VII.—NO. IX. 25 
