Egypt : handbook for travellers / edited by K. Baedeker.

Date:
1885-1892
Catalogue details

Licence: Public Domain Mark

Credit: Egypt : handbook for travellers / edited by K. Baedeker. Source: Wellcome Collection.

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    middle of the Delta, while the Pelusiac and Canopic months, the most important in ancient times, lay at the extreme east and west ends of the coast respectively. The water was afterwards gradually compelled to seek other outlets. The Pelusiac arm found a convenient exit through the Phatnitie near Damietta, while the Canopic was artificially conducted into the Bolbitinic. All the principal arms of ancient times at length en- tirely disappeared, combining to form the modern outlets. These last will in their turn he abandoned, as the river will doubtless again force for itself a more direct passage with a greater fall. Geological Notice (by Prof. Zittel). (1) Egypt Proper. There is no exaggeration in the often repeated saying that Egypt is ‘the gift of the Nile’. But for the bounties dispensed by the river, what is now the most fertile country in N. Africa would be a wilderness of bare rock or sand. With the greatest height attained by the inundation and the extreme length of the irrigation canals corresponds precisely the line which di- vides the Sahara from the cultivated land. The whole of the alluvial soil deposited by the Nile is an entirely foreign element in the geologi- cal structure of N. Africa , and its geological character is uniform and easily determined. The origin, composition, and thickness of the alluvium has already been stated. The perpendicular, black, and furrowed mud-banks, which often rise to a height of 25-35 ft., are composed of distinct parallel strata of somewhat different colours, with thin layers of sand occasionally in- tervening. In Lower Egypt the mud is rather more thinly spread over the whole Delta, in the form of a blackish or reddish-brown laminated mass, a few isolated spots only remaining uncovered. Wherever the ground is denuded of its alluvium, apart from which there is no permanent soil in Egypt, it is absolutely sterile; for in this hot and dry country there is no winter, with its protecting mantle of snow, to retard the decomposition of vegetable matter, and to promote its admixture with disintegrated rock, so as to form fertile soil. Owing to the want of vegetation and moisture, without which the progress of disintegration is reduced to a minimum, the surface of the naked rock in Egypt and the neighbouring deserts retains its character almost un- altered. The huge masses of debris observed at the foot of the rocks in the valley of the Nile, and particularly at the mouths of the wadies, and the curious isolated hills with which every traveller through the desert is struck, could not possibly have been formed during the present state of the Egyptian climate. They prove that at some pre-historic period the now parched and sterile ground must have been overflowed by co- pious volumes of water which produced these and various other effects on the appearance of the earth’s surface. The geologist will find little to attract his attention in the alluvial soil of Egypt; but on the sea-coast, and in that part of the isthmus which is intersected by the canal, there are several points of interest. On entering the harbour of Alexandria the traveller will observe the massive blocks of stone from the quarries of Meks of which the quays are constructed. They consist of recent tertiary, light-coloured, sandy limestone, composed chiefly of innumerable broken fragments of con- ckylia, a kind of rock which extends far to the W. of Alexandria, and probably constitutes the greater part of the lofty Cyreneean plain. This rock forms the building-stone generally used at Alexandria, and is also employed in the harbour-structures of Port Safid. Amidst the desert sand of the isthmus, which even in Lower Egypt forms a substratum underlying the Nile mud, and which in the E. part of the desert is nearly covered with a solid gypseous and saline crust, the rock occasionally crops up , or has been uncovered in the course of the excavation of the canal. Near the Shaluf station (p. 432) a greenish-grey, gypseous marl overlies the solid limestone, which contains the tertiary marine conchylia,. sharks’ teeth, and remains of crocodiles and am- phibious mammalia. The same formation occurs in other places also, and ridges of the early tertiary nummulite limestone likewise occasionally