SOME GEOGRAPHICAL ASPECTS OF THE NILE.« 



[With 5 plates.] 



By Capt. H. G. Lyons, F. R. S., F. R. G. S., 

 Director-general of the Survey Department of Egypt. 



The geographical exploration of the basin of the upper Nile "was 

 actively prosecuted during the second half of the last century, but the 

 Mahdist rebellion closed this region to travelers in 188-i, and for the 

 next fifteen years but little could be done. In 1899 the capture of 

 Omdurman and the defeat and dispersal of the Dervish forces once 

 more opened the southern Sudan to European activity. In the mean- 

 time Egypt, under a stable government and an efficient organization, 

 had increased marvelously in economic prosperity. Improvements in 

 the irrigation system enabled the cultivator to receive regularly the 

 water which he required, and the construction of the Aswan reservoir 

 furnished a supply of water which sufficed, with strict economy, to 

 meet the most pressing needs of the country and its rapidly increasing 

 cultivation during the low stage of the river. But more water was 

 necessary if the waste lands on the northern margin of the delta were 

 to be reclaimed and cultivated. The Blue Nile, which falls rapidly in 

 the autumn months, was obviously useless for this purpose, so that the 

 study of the A\niite Nile and its tributaries was the first step toward 

 the solution of the problem. 



During the past nine years much has been done in this direction, 

 and now the main characteristics of the various portions of the river 

 system have been ascertained. It may be of interest, therefore, briefly 

 to la}^ the results before the society. 



In Egypt, from the earliest period of antiquity, the annual flood 

 of the Nile was recognized as the most important phenomenon of the 

 year, and it attracted the attention of the dwellers in the valley both 

 on account of its importance to them and from its occurrence in a 

 region where the climate is practically rainless. According to Herod- 

 otus, the ancient Egyptians considered the river as flowing from two 



'^ Read before the Royal Geographical Society, June 29, 190S. Reprinted, by 

 permission, with author's corrections, fx'om The Geographical Journal, London, 

 Vol. XXXII, No. 5, November, 1908. Plates 1 to 4, photographs by E. M. 

 Dowson ; plate 5, photograph by Doctor Borchardt. 



481 



