Engineering Wonders of the World
Volume III

THE GREAT IRRIGATION WORKS OF INDIA. 233 MAP y A & SHOWING ANNUAL RAINFALL OF INDIA. The figures and lines indicate the number of inches in the various districts. £ i BOMB COON 30 - A y A S C?”K s factory has been the social effect of the works upon the people to whose needs they minister. The Swat River Canal, which lies in a district on the borders of the Punjab, for- merly the home of very turbulent frontier tribes, did more in ten years to still that tur- bulence and settle the people quietly in the villages than could have been effected by all the police of the Province in half a century. The rulers of India see in the great irrigation works, not only a sound financial investment, but, what is far more important, a political force and a powerful and beneficent means of convincing the agricultural classes—far the most numerous and important in the country — that Britain rules India primarily and emphatically for the good of the silent and persevering races which people it. The Indian Irrigation Commission of 1901— 1903 estimated that of the gross Indian rain- fall 35 per cent, was carried by the rivers direct to the sea, 59 per cent. was either evaporated from or °* absorbed by the soil or uti- lized in sustaining plant life, and only 6 per cent, was used for artificial irrigation. It is not possible, for many reasons, to utilize the whole of the 33 per cent, which now flows use- lessly to the sea, as a large proportion of the whole surface flow of India runs off the West- ern Ghauts, which slope steeply to the Arabian Sea, south of Bombay. But as time goes on more and more of it will be entrapped and turned to good account. For centuries before the British occupation irrigation had been practised in India, the same systems being used then as now — namely, perennial irrigation with water led through channels tapping a river far above the district watered, or from storage reser- Irrigated Areas.