132 Book of Engineering 



Britain sent out 80,000 tons of cement, 

 and close upon 10,000 of steel sheet piles 

 were required. The barrage represented 

 over 300,000 tons of rubble masonry and 

 concrete, merely for foundations, and over 

 20,000 concrete blocks, each of which 

 weighed 4^ tons, were placed in the aprons. 



Possibly the work could not have been 

 accomplished in so short a time had it not 

 been for the employment of five electrically 

 driven aerial cableways which were estab- 

 lished on either bank of the Nile. By this 

 means it was possible to bring the heavy 

 concrete blocks into position, and drop 

 them where required. 



Thousands of men were employed, and 

 the work had to go forward at breakneck 

 speed whenever the condition of the river 

 allowed it. 



