144 Travels in Nortftern Africa and Western Asia. 



is one of the largest of these branches. From Bir-el, Ghorallant 

 to the S. W., they traversed an undulated plain, covered with a 

 thin layer of sand and limestone debris, and reached the foot of 

 the Katabathmus Major, or El Akaba el Kebire. This plain is 

 the boundary of Egypt and the country of Cyrene ; it is 800 feet 

 above the sea, extends to the west and south to a great distance, 

 and is composed of strata of the same whitish secondary lime- 

 stone. In passing from thence to Siwa, they had opportunities 

 of examining the sand, which covers the plain, but is not deep, 

 and is sometimes replaced by remains of silicified shells, among 

 which, however, they did not find nummulites. The descent 

 from the plain to the basis of Siwa is over seven terraces, and 

 among grotesque rocks. 



The slopes of this plain present specimens of siliceous woods 

 near the plain of El Gatara, and in the part called Gebel Scha- 

 tar, the ground is covered with a saline crust in an oasis not far 

 from this. At Bir-Haie, there are also fossil Avoods and aetiles 

 with quartz crystals at the foot of the slope of the plain. They 

 followed the route from Siwa to Alexandria, where the ground 

 is saline as far as Wadi Lebuk, where the sandy or rocky ground 

 recommences. Farther on, the author found many petrified 

 trunks of palms and of dicotyledonous plants, some of then^ 

 from five to six feet long. The bark was preserved in the dico- 

 tyledones, but not in the palms. A coloured geological map 

 gives an idea of the geological constitution of the country tra- 

 versed. There are first seen the alluvia of the Delta of the 

 Nile between Alexandria, Cairo, and Damietta. To the east, 

 between the two last cities, the Delta is bordered with sandy 

 and pebbly hillocks. Between the pyramids of Cairo and the 

 Lake Mareotis, they point out to the south the dried up bed- 

 of ancient streams. , 



Farther to the south, between Lake Moeris and Karb-Scha- 

 raamel el Scharkie, the lower desert is covered with an alluvial 

 formation, characterized by pebbles of Egyptian jasper, siliceous 

 woods,, and nummulites, which liave come from the higher lime- 

 stone mountains of Egypt, and perhaps even from Mokattam. 

 The high plain of the desert, between Bii'-Lebuk, Katabathmus 

 Parvus, the other promontory called by the ancients Catabath- 

 mus Magnus or Kasreschdacbi, Siwa and Bir-Haie, is tertiary. 



