Dr. John Ball— The Gulf of Suez. 7 



but my point is that they have no direct genetic connexion with the 

 Gulf of Suez as we now know it, having taken place at a prior epoch 

 to that of the erosion and submergence of the gulf. The rift-valleys 

 of Eastern Sinai, observed by Dr. Hume, 1 are all parallel to the Gulf 

 of Akaba, which is admittedly a trough-subsidence, and therefore show 

 a true relationship with that gulf. But no undoubted trough-fault 

 has ever been observed parallel to the Gulf of Suez, and there is no 

 evidence for the existence of a second system of rifts inclined at 

 a considerable angle to those of the great Dead Sea system, except the 

 Red Sea itself. In his exploration of Western Sinai Mr. Barron 2 

 regarded only one line of valleys as safely attributable to ' rift ', and 

 the chief factor on which he based his judgment was parallelism with 

 the Gulf of Suez. But to use this as any support in regarding the 

 Gulf of Suez itself as a trough would be to argue in a circle. 



The view of an erosive origin for the Gulf of Suez is, I think, now 

 supported by strong evidence. As to its being an anticline, the 

 evidence is but little less conclusive. The strata of the Galala 

 mountains on the one side and those of Gebel Hammam on the other 

 dip away from the gulf, so that in the north at least the gulf possesses 

 an anticlinal structure. In the south part we have at present less 

 complete data, and it is quite likely that the anticlinal structure there 

 may be less simple and less pronounced than it appears to be in the 

 north. But such observations as have been made are all in the 

 direction of a general similarity of structure right down the gulf. 

 Thus the beds forming the long coast-ranges north of Tor all dip away 

 from the gulf, exactly as do those of Gebel Hammam, and the Nubian 

 sandstones at the north end of Gebel Zeit likewise dip inland ; 

 while such scanty information as we possess from the islands near the 

 Strait of Jubal all tend to indicate that an anticlinal structure is 

 present there. The numerous borings now being made by prospecting 

 companies on the islands will, we may hope, soon lead to more complete 

 knowledge of the structure and nature of the rocks composing them. 



It is interesting to see how easily we may trace the later geological 

 history of North-Eastern Egypt on the view of the erosive origin of 

 the Nile Valley and Gulf of Suez, together with those secular 

 oscillations of the earth's crust in the district of which we have 

 equally strong evidence in the numerous observations of Beyrich, 

 T. Euchs, Schweinfurth, Hull, and others. Any attempt at the 

 reconstruction of the geological history of this part of Egypt must 

 take account of the following facts, 3 in addition to those which 

 I have brought forward to prove the erosive origin of the Nile Valley 

 and the Gulf of Suez : — 



1. The great depth of the bed-rock channel of the Nile in Lower 

 Egypt, as proved by numerous trial borings ; these borings all show 

 a great thickness of sands and gravels to intervene between the present 

 bed of the Nile and the bed-rock of its channel. 



1 ' ' The Eift Valleys of Eastern Sinai ' ' : International Geological Congress, 

 Paris, 1900. 



2 Western Sinai, p. 180. 



s Most of these observed facts will he found summarized in Suess' Face of the 

 Earth, English translation, vol. i, p. 380, 1904. 



