60 NORTH-EAST APEICA. 



chief commercial outlet of all Upper Egypt. Over fifty years ago the English 

 already sank wells at intervals along this gorge, with the view of utilising it for 

 the overland route to India. 



After flowing westwards below the great bend of Keneh, the Nile trends north- 

 west and north ; but in this part of its course it bifurcates, one arm branching 

 off and flowing parallel with it on the west side at a mean distance of seven 

 miles. This is the Bahr-Yusef, or " River of Joseph," so called in memory of 

 Pharaoh's minister mentioned in the Jewish traditions, or rather of a certain Joseph, 

 minister of the Fatimites in the twelfth century. But it does not appear to have 

 been excavated by the hand of man, although it has been frequently embanked, 

 deflected, and directed into lateral channels, like all the running waters of the 

 valley. Recently the point of derivation has been displaced, and the canal named 

 Ibrahimieh has been raised to the level of the high banks in order more easily to 

 regulate the discharge of the flood waters. In the part where it has not been 

 canalised the Bahr-Yusef, skirted along its left bank by the dunes drifting before 

 the desert wind, is a winding stream like the Nile, having, like it, its islands, sand- 

 banks, eroded cliffs, and network of watercourses and false rivers. Its mean breadth 

 is about 330 feet, but through it very little of the Nile waters are distributed. 

 Feeders from the main stream, in traversing the intermediate plain, replenish the 

 River of Joseph at intervals, thus making good the losses caused by evaporation. 

 This phenomenon, of two parallel streams in one and the same valley, one the 

 main stream discharging nearly the whole liquid mass, the other a small current 

 winding through an ancient river bed, recurs in nearly all those valleys whose 

 hydrographie system has not yet been completely changed by canalisation and 

 drainage works. Several rivers skirted by embankments have also their Bahr- 

 Yusef, like the Nile. Such in France is the Loire, skirted by the Cisse, by the 

 waters derived from the Cher, the Indre, and the Vienne; lastly by the river 

 Authion, with its numerous ramifications. 



The Fayum Depression. 



About 300 miles from the point of bifurcation, the Bahr-Yusef penetrates into 

 a lateral valley, where it ramifies in its turn. The eastern branch, which con- 

 tinues the river properly so-called, penetrates north-eastwards through a breach 

 in the Libyan range, beyond which it rejoins the Nile above its delta. But the 

 western branch trends abruptly north-westwards to a rocky gorge, at the entrance 

 of which its course is regulated by a three-arched bridge built in the thirteenth 

 century, and furnished with flood-gates allowing the stream to pass, or diverting 

 it to the surrounding plains. Beyond the barrage the canal winds through a 

 ravine about 6 miles long in the Libyan range, at the outlet of which it suddenly 

 debouches in a valley of amphitheatral form, and nearly 110 miles in circum- 

 ference. This is the Fayum depression, which is watered by an intricate system of 

 canals, rills, and rivulets, ramifying like the veins and arteries in a living organism. 

 At its lowest point this hill- encircled basin is estimated at from 86 to 116 feet 



