38 ■ 



yards b}' partially closino^ the head gates of the main canal during 

 high water and supplying it through the smaller canal already referred 

 to, di\erting water -i^ miles north of Cairo. Considerable work is 

 required each year at the head gate of the supply canal. It is over a 

 quarter of a mile from the bank of the river. The channel leading to 

 this head gate tills Avith back water from the river during high Nile 

 and immense quantities of mud are deposited. 



Many of the canals in the delta are ancient river channels. Those 

 taking water from the Nile at the barrage are artificial. Among these 

 latter is the Manutia Canal (frontispiece). M'hich is one of the most 

 cele])rated in Egypt. It furnishes water for the irrigation of nearly 

 all the land in the delta lying between the two branches of the Nile. 

 The head gate of the canal is similar in design to the barrage itself. 

 (PI. XI, lig. 2.) A lock has been provided at the head gate, and the 

 canal furnishes an important waterway for the internal commerce of 

 the delta. The canal is from 160 to 175 feet wide on the bottom, and 

 at high water carries nearly 3<> feet of water in depth. Its summer 

 discharge is nearly 4.(MK) cubic feet per second. 



The Tewtiki Canal diverts water from the Damietta branch of the 

 Nile at the eastern extremity of the barrage. It was l^egun many 

 years ago. but was not finished until after the occupation by the 

 English. It furnishes water for a large area Wing east of the Dami- 

 etta branch, and its construction has added greatlv to the value of this 

 region through the introduction of perennial irrigation. The Behera 

 Canal leaves the Rosetta branch of the Nile at the western extremity 

 of the barrage. It is about Gi» feet wide on the bottom, with slopes of 

 2 to 1. It runs for a considerable distance along the margin of the 

 desert, hence receives large volumes of sand which, with the silt 

 deposited during high Nile, have to be cleaned from the channel each 

 year. Until recently nearly 1,000,000 cubic yards had to be removed 

 annually, and, in spite of the enormous amount of work performed, 

 the canal carried less than 600 cubic feet of water per second. The 

 Behera Canal is about 25 miles long. At its lower extremity the 

 Katatl>eh Canal 1)egins. It has about the same dimensions as the' 

 Behera Canal. It supplies all the smaller canals to the north and 

 west. The surplus water from the drainage of the land it serves flows 

 into Lake jNIareotis. The Mahmoudia Canal begins 34 miles from the 

 barrage of the Rosetta ])ranch of the Nile. This canal runs for about 

 •15 miles to the northwest and ends at Alexandria. It supplies fresh 

 water for that city besides furnishing water for irrigating a large 

 area. The Mahmoudia Canal has for a long time been supplied with 

 water b}' means of immense pumps located at Atfeh. Since the repair 

 of the barrage the pumps of Katatbeh have been removed to Mex, 

 which station keeps down the level of Lake Mareotis, 



