254 



Selections. 



[NO. 6, NEW SERIES, 



alluvial land fertilized by the sediment from the annual inunda- 

 tion must have "been cultivated in the returning seasons. The 

 next following flood softens the hardened mud of the preceding 

 year, and it is considered that this softening of the soil is one of 

 the most fertilizing effects of the inundation. The very primitive 

 and simple system of cultivation at the present day is, most pro- 

 bably, the same which has been followed for unknown ages, for it 

 is said that in Egypt nothing changes. As the subsiding inunda- 

 tion level continues to expose to air and light the surface on 

 which the sediment has been deposited in insulated patches of the 

 uneven ground, the Fellah, wading in mud begins to throw seed 

 upon them in contour lines, his light boat bringing to him his seed 

 corn. As the retreating waters expose more land, as soon as it is 

 sufficiently drained another zone of ground is sown, and so on until 

 the lowest parts have received the seed, which must be cast be- 

 fore the surface begins to crack, and after it has been cast it is 

 beaten down into the mud with a flat piece of wood attached to 

 the end of a pole. During the dry season, when vegetation withers, 

 and the underground water has subsided, the ground cracks in 

 to numerous and deep fissures, forming the usual polygonal figures 

 we see in dry mud or clay, affording receptacles for the flying sand. 

 For three or four months in every year the surface of the valley 

 stript of vegetation, in the state of a dry powder* is swept by violent 

 winds, raising clouds of dust. By these combined causes, there- 

 fore, every trace of the deposited layer must be effaced. Instances 

 of lamination and alternation of clay and sand, such as those 

 mentioned by Captain Newbold, are not unfrequently met with 

 on the banks of the river and at the entrances of canals, but 

 they are local occurrences, caused by eddies and currents. 



A further result of these researches is, that there are occasional 

 accumulations of soil, the materials of which are only remotely 

 derived from the inundation water and the storms of desert sand. 

 In the neighbourhood of old buildings and on the sites of earlier 

 buildings, where these have been constructed of crude bricks, the 

 soil, to a considerable depth, may have been derived from the dis- 

 integration of these bricks. The soil thus derived would have 



