74 Dr. John Ball—The Nile Valley and Gulf of Sues. 
It will of course be remarked that an immense amount of erosion 
must have gone on in the gulf to remove the folded-up strata, while 
the trough-fault theory would not demand this. But one has to 
remember that in the case of the Wadi Araba there can be no doubt 
of erosion on this immense scale having taken place; for it is 
impossible to doubt the original continuity of the Eocene over the 
Wadi Araba, and the Carboniferous beds in the wadi-floor show that 
the Eocene has not been faulted down, so that it must have been 
eroded out. Vast ages must have been occupied in this erosion, even 
if it took place part passu with the folding of the anticline. But with 
the greater space of time which physicists now allow us for the earth’s 
evolution since the discovery of radio-active minerals, geologists will 
not feel that the time demanded for the erosion is any obstacle to 
believing it to have taken place. 
The conviction that the Gulf of Suez is an eroded anticline and not 
a trough fault at once removes an important support from the ‘rift 
theory’ of the Nile Valley. For both the Nile Valley and the Gulf 
of Suez have on this theory been regarded as due to carth-movements 
of similar type acting about the same time, and if we show the 
movements postulated to have been non-existent in the one case, 
a doubt at once arises about the other. 
I have made a search through the various publications to find out 
the history of the ‘rift theory’ as applied to the Nile Valley and the 
evidence relied on for its support. The earliest reference published 
appears to be in a paper read by my friend and former colleague 
Mr. Beadnell at the International Geological Congress at Paris in 
1900, an abstract of which appeared in the Gronoeican Macazinn 
of January, 1901 (p. 23). Though Mr. Beadnell informs me that he 
no longer considers the trough-faulting of the Nile Valley to be 
a necessary conclusion from his observations, he has set out so clearly 
in his paper the only grounds on which the ‘rift theory’ rests, that it 
is advisable to quote them here as affording a definite basis for 
discussion. The facts which led Mr. Beadnell to the view that the 
Nile Valley had its origin in carth-movements and was not the result 
of erosion are as follows :— 
(1) The general north and south direction of the Nile Valley in 
Egypt. 
(2) The remarkable high, lofty, wall-like cliffs by which it is 
hemmed in. 
(3) The absence of any true river-deposits at any considerable height 
above the river. 
(4) The almost entire absence of hills or outliers of the plateau 
within the valley. 
(5) The proved existence of bounding faults throughout a long 
stretch of the valley. 
The whole weight of the evidence lies in the last fact given, the 
first four having but little significance in themselves. As regards the 
general direction of the valley, it is by no means straight; the greater 
part of it is approximately parallel with the Gulf of Suez, but if that 
gulf is not a trough there is no argument by analogy of direction. 
