FORESTRY AND IRRIGATION 



73 



Their indifference, however, was due 

 to other plans which they considered 

 more practicable, and it was determined 

 to construct an enormous dam at the 

 first cataract near Assuan, which stores 

 all the water that is not needed at the 

 annual inundation and allows it to be re- 

 leased when it is needed later in the sea- 

 son. This dam is now completed. 



It was begun in February, 1898, a 

 contract having been entered into with 

 Messrs. Aird & Co., a Scotch firm, who 

 agreed to build it for $10,000,000, pay- 

 able in thirty semi-annual installments 

 of $400,000 each, including interest; but 

 they do not get a dollar until it is com- 

 pleted. The foundations of the dam 

 rest upon solid granite ledges; it is 6,786 

 feet, or about a mile and a quarter, long, 

 1 20 feet high from the rock bottom, 82 

 feet thick at the base, and 26 feet wide 

 at the top, where there is a roadway 

 guarded by walls which take the place 

 of the bridge which has long been 



needed. The dam contains 1,250,000 

 tons of masonry and about 15,000 tons 

 of steel. The masonry is of rough gran- 

 ite blocks laid in cement, and the mate- 

 rials have been taken from quarries 

 which for 7,000 years supplied stone for 

 the obelisks, pyramids, temples, tombs, 

 and palaces of Egypt. There are 180 

 sluices through which the water can be 

 released when it is needed, and they are 

 fitted with steel gates that can be han- 

 dled by electric machinery. Every con- 

 venience and apparatus known to science 

 has been applied where it is needed, and 

 if this dam had been built a thousand 

 years ago it would have been ranked 

 among the wonders of the world. 



It is one of the greatest engineering 

 triumphs in history. Its construction 

 has been immensely more difficult than 

 the Suez Canal, and it differs from that 

 famous public improvement in the im- 

 portant particular that no money was 

 stolen or wasted. 



NATIVE LABORERS AT WORK ON THE LOCKS. 



