PROCEEDINGS, 
ETC. 
POSTPONED PAPERS. 
On the Geology of Ecyrt. By Lieut. NewBoip, Madras Army, 
FBS. 
[Read June 29, 1842.—Communicated by the President. ] 
I wAveE deemed it advisable to preface this paper with a brief notice 
of the geographical position, extent, and more prominent physical 
features of Egypt, remarking at the same time that although much 
still remains to be done in this most interesting, and comparatively 
unexplored field for the geologist, yet it may not be wholly useless to 
lay before the Society a summary of what has already been effected. 
Geographical Position and Extent.—Kgypt, with its desert tracts, 
embraces an area of about 100,000 square miles, having somewhat 
the shape of a parallelogram, the longest axis of which runs north 
and south. It is situated between 24° and 32° N. lat., and 27° and 
31° E. long., and is bounded on the north by the Mediterranean, on 
the south by the mountaims of Nubia, on the west by the Libyan 
desert, and on the east by the Red Sea and the Isthmus of Suez. It 
possesses a coast-lme on the Mediterranean upwards of 200 miles 
long, and on the Red Sea of more than double that extent. 
Physical Divisions.—Egypt consists of three great physical divi- 
sions: first, the mountamous region, extendmg between the Red 
Sea and the Nile; second, the desert tracts east and west of the Nile; 
third, the fertile valley of the Nile and its delta. 
Aspect.—The general aspect of Egypt varies according to the 
divisions just laid down, and presents perhaps more striking contrasts 
of sterility and fertility than any other country in the world. The 
mountainous region exhibits, from deficiency of springs, rain, and 
dew, all the naked, dreary appearance of Arabia Petreea—an assem- 
blage of bare or sand-covered rocks, intersected by deep ravines” 
offen obstructed by rocky debris, and the drifted sands of the desert, 
which frequently mvade the sides and summits of lofty hills. The 
peculiarly flat, tabular aspect of Central, and part of Upper Egypt, is 
owing to the almost horizontal character of the stratification of the 
limestone rocks that for the most part prevail, supporting the desert 
tracts on each side of the Nile, and terminating near its banks in 
mural escarpments, which flank its course with some irregularity, from 
the vicinity of Esneh to Cairo. Between Kossier on the Red Sea and 
Ghennah on the Nile, where plutonic and hypogene rocks prevail, 
