CH. V] DRAINAGE AND IRRIGATION 23 



at a great cost, an irrigation rate is charged upon all the 

 land watered by it, and in many parts of India the irrigation 

 works pay a good dividend through these rates. Thus in 

 parts of Madras, the rate is Rs. 7 (105.) an acre a year, and 

 for this a certain fixed amount of water is allowed. In the 

 south of Ceylon, on the other hand, where the work of making 

 the irrigation dams, etc., is simple and cheap, and is done by 

 the people themselves, there is a terrible waste of water, though 

 luckily there is so much rain that this very rarely matters. 



One of the most wonderful systems of irrigation that ever 

 existed is that which was put into practice in the north of 

 Ceylon in the early days of the Sinhalese monarchy, 2000 years 

 ago, which fell into entire ruin during the Tamil invasions from 

 700 to 1300 A.D., and which is now, at great cost, being slowly 

 restored by the Ceylon Government. The north of Ceylon is a 

 " dry " country, i.e. it only gets rain for about four months in 

 the year, and must have irrigation. Almost every valley was 

 dammed up, the country being gently rolling, by an earthwork 

 or " bund " within 20 or 30 miles of its head, and other bunds, 

 gradually getting longer and longer, and less and less high as 

 the sea was approached, were made across the valley at intervals 

 of a few miles, lower down. During the rainy season these 

 reservoirs became filled. The overflow from the first "tank" 

 (to give the reservoirs the name by which they are known in 

 Ceylon), together with the waste water from the rice fields 

 below it, was of course caught in the second tank, and so on. 

 Not only so, but from the uppermost tank a canal was taken at 

 the highest possible level, winding round the side valleys at as 

 gentle a slope as possible, and feeding the tanks that were also 

 made in these valleys. In this way almost the whole of every 

 valley was made irrigable, and there was practically no water 

 allowed to reach the sea until it had done the maximum of 

 work. Some of the tanks were of enormous size ; Kalawewa, 

 for example, now restored, has a bund about 6 miles long, and 

 60 feet high at the centre of the valley, while the tank is about 

 5 miles by 2, and in the old days, when the water was retained 

 at a higher level, was about three times that size, while other 

 tanks are even larger. The canal on the north side of Kalawewa 



