106 EXPERIMENT STATION RECORD. 



years later was irrigating 1,829,000 acres, supporting a population of 

 eight hundred thousand inhabitants, who were brought there from more 

 congested parts of India. The Ganges (anal, opened in 1854, "at a 

 time when there was not a mile of railway and hardly a steam engine 

 within a thousand miles." has a length of nearly ten thousand miles, 

 including distributing canals. Supplemented by the low T er canal, 

 drawn from the same river, it irrigates 1,700,000 acres annually. 



A very bold and successful piece of irrigation engineering in south- 

 ern India, which was completed a few years ago, diverts the waters of 

 the Periyar River through the mountains to the plains on the other 

 side. The river formerly descended to the sea on the west coast, 

 where its waters could not be utilized, and large expenditures were 

 required periodically to control its furious floods. A dam was built 

 across its course and a tunnel made through the mountains, enabling 

 the reservoir to be discharged into a system of canals to the east and 

 applied to the irrigation of a vast area much in need of water. 



In the state of Mysore a reservoir is now under construction which 

 closes a valley containing over two thousand square miles by means of 

 a masonry dam 142 feet high. The reservoir thus formed will contain 

 30,000 million cubic feet of water when filled, which, however, will 

 rarely occur, the reason for the height of the dam being an engineer- 

 ing one rather than the need of ordinarily impounding such an 

 enormous volume of water. 



Perhaps there are no more familiar examples of the wonders 

 wrought l;ry irrigation than those furnished by Egypt, but to the la}'- 

 man Mr. Moncrieff's statement that purel} T agricultural land near 

 Cairo, where the average rainfall is only 1.4 inches, is sold as high 

 as $750 an acre is a revelation of the value which irrigation has placed 

 upon these desert lands. 



Here, it will be remembered, is the great Assuan Dam, six hundred 

 miles below T Cairo. This dam holds up a depth of sixty-six feet of 

 water, forming a lake of more than one hundred miles in length, 

 extending up the Nile Valley, and containing 38,000 million cubic feet 

 of water. The chief object of this great reservoir is to enable peren- 

 nial irrigation to be substituted in upper Egypt in place of the basin 

 system of watering the land through the Nile flood only — that is, to 

 enable two crops to be grown every year instead of one, and cotton 

 and sugar cane to take the place of wheat and barley. It is expected 

 that these works on the Nile will be finished in 1908. There will then 

 have been spent on the great dam at Assuan, the minor one at Assuit, 

 and the new canals of distribution in upper Egypt about £6,500,000, 

 or approximately $31,525,000. 



Not only will this undertaking have a far-reaching effect upon the 

 agriculture of the country, the methods of cropping, and the handling 



