THE LOWER NILE. 67 



over a lofty granite ledge. The desert east of the rapids is intersected by an old 

 branch of the river running at several yards above the present high-water level. 

 Even the most superficial observer of natural phenomena cannot fail to perceive 

 that he is travelling in a now abandoned watercourse. He still perceives the 

 windings of the stream between rocks covered with hieroglyphic inscriptions; 

 he observes its old cliffs and banks, and here and there the alluvia are still revealed 

 under the billows of sand drifting before the winds from the desert. The records 

 deciphered by archaeologists describe the march of armies along this old river bed, 

 from the times of Thotmes and Eameses down to the present day. According to 

 the observations made by Lepsius at Semne above the second cataract, it is probable 

 that, from the beginning of Egyptian history, this dried-up channel was once 

 flooded by a branch of the Nile. During the reign of Amenemha III., some 

 4,700 years ago, the watermarks engraved on the rocks at this place show that the 

 flood level exceeded by many yards that of the present time : the highest water- 

 mark exceeds by 25 feet, the lowest by 13 feet, the corresponding levels of 

 modern days. On the right bank of the Hannek cataract also M. de Gottberg 

 has found alluvial deposits 10 feet above the level of the highest modern floods. 

 May not the waters have been thus arrested by the cataracts, and forced to flow 

 into the now dried-up valley which serves as a highway between Eg3rpt and 

 Nubia ? Above the Batn-el-Hagar rapids are to be seen many tracts formerly 

 cultivated but now quite sterile, since the waters of the floods no longer reach 

 them. Like all river valleys whose beds are regulated by the action of running 

 waters, that of the Nile establishes its equilibrium by falling in Nubia and again 

 rising in Lower Egypt. M. de Gottberg accounts for the lowering of the water- 

 level in Nubia through the disappearance of cataracts formerly existing between 

 Wadi-Halfa and Asuau, traces of which are still visible. The rocks forming these 

 cataracts consist of schists, which, unlike the crystalline reefs, yielded to the 

 destructive force of the stream. The granite rocks themselves also yield to the 

 same action, but much more gradually. 



The Lower Nile, 



Below the granite ledge washed by the waters of the first cataract, the cliffs 

 lining the river bank are composed of layers of sandstone, succeeded farther on by 

 limestone rocks. Historic Egypt begins at the foot of this rocky barrier, which is 

 covered on either side by tertiary deposits. North of Asuan the banks of the river 

 are at first separated only by a space of from two to three miles. The fields and 

 plants henuned in between the escarpments and the stream present on either side 

 nothing but a narrow strip of verdure winding along the foot of the grey or yellow 

 rocks, which glitter like burnished gold in the sun. The cultivated zone lies chiefly 

 to the west, along the so-called " Libyan " bank, which is most exposed to the solar 

 rays. Like most other rivers of the northern hemisphere, the Nile bears chiefly 

 towards its right bank, the current skirting the foot of the rocks, which at some 

 points rise sheer above the stream. The towns stand mostly on the left bank, 



