518 Reviews — BeadneWs Geology of the Fatjum, Egypt. 



lake (Birket el Qurun), also sands blown from the desert, and 

 alluvial deposits. 



" In a thickness of 700 metres (2,266 feet) these beds include 

 every kind of sedimentary deposit — limestones, marls, clays, sand- 

 stones, sands, and gravels, forming an ever-changing succession 

 of rocks, varying considerably in hardness and capacity for with- 

 standing the agents of denudation. It is not too much to say 

 that the coming into existence of the Fayum, with its plains, low- 

 lying depressions, precipitous cliffs and escarpments, was largely 

 dependent on the nature of this variable series of deposits " (p. 15), 

 out of which this hollow has been carved. 



In reference to the origin of the Fayilm, Dr. Blanckenhorn 

 describes it as a triangular depression hounded on all sides by faults, 

 the position of which he shows on a map accompanying his paper.' 

 "As these fault-lines lie for the most part within the area covered by 

 the alluvial deposits and the waters of the lake, it is not easy, for 

 want of exposures, to disprove their existence. But the fault along 

 the east side follows the junction-line between the desert and the 

 cultivated lands. Along this line everywhere the marls and lime- 

 stones of the Ravine-beds pass regularly from the desert under the 

 cultivated lands without any sort of break or dislocation, whilst an 

 exairiination of the desert ridge to the east disproves the existence of 

 any faulting on the desert side." " A few kilometres to the west the 

 same beds appear in the ravine of El Bats, proving their continuity 

 under the cnltivnted alluvium in this direction." The author deals 

 with all the other faults propounded by Dr. Blanckenhorn, and con- 

 cludes, after careful examination, that no evidence in favour of the 

 existence of such faults was met with, and that everywhere the 

 strata occupy their normal undisturbed level stratigraphical position 

 (pp. 30 and 31). 



" No evidence has as yet been met with," says Mr. Beadnell, 

 " which would suggest that earth-movements have played any 

 important part in the formation of the Fayum depression. In fact, 

 an examination of the desert margin conclusively proves that the 

 depression has been cut out through the action of ordinary subasrial 

 denuding agents" (p. 29). 



The author pictures the condition of the Fayum in Eocene times, 

 and suggests that a great river flowed in a north-easterly direction 

 along the line of the Baharia Oasis from a well-wooded continental 

 area hundreds of miles to the south, carrying along with it in flood- 

 time vast masses of matted rafts of forest trees, and bearing seawards 

 the carcases of those curious Eocene animals the remains of which 

 are so abundant in the Fayum of to-day. 



The memoir is distinctl}' in advance of its predecessors both in the 

 printing and in the quality of its illustrations, which have been very 

 carefully executed; the frontispiece, representing the Bahr Yusef 

 at Lahun, before entering the Fayinn, is an excellent picture, and the 

 plate (x) of the El Qatrani range, showing the magnificent basalt- 

 capped cliffs, is also very good. The plate of the isolated sand-dune 



' Blanckenhorn, " Geologie Aegyptens," Berlin, 1901, pt. iv, pp. 339-344. 



