190 EGYPTIAN AGRICULTURE. 



9 J kilometres in width, north to south. The bed of the 

 lake was nearly a dead level, one metre below sea, rising 

 by a gentle slope to R.L. 0*50 on the west and east margins. 

 Aboukir was not a permanent lake. Drainage from 

 adjoining cultivated land on the east, and winter rainfall 

 averaging 20 centimetres per annum caused an accumulation 

 of water in the lower parts to a depth of 30 centimetres 

 in winter, but this was evaporated during summer leaving 

 a crust of white salt, nearly pure sodium chloride, a few 

 centimetres thick. Clearly marked traces of old water 

 channels and remains of foundations of houses confirm 

 historical proof that Aboukir was cultivated, probably till 

 the middle of the eighteenth century when an irruption 

 of the sea destroyed the cultivation. 



Voslcker's analyses of two samples of soil from the bed 

 of the lake taken at different points give the following 

 results: 



A iK.)I~ K IK SALT SOIL. 



Containing nitrogen 0*035 0*070 



: Ammonia .. 0'042 0'079 



