THE GANGES PLAIN.—Throughout the whole of the Ganges plain there is a dense population, and agriculture is the chief occupation of the people, but the conditions under which it is pursued, and the crops grown, vary from one division to another. In the western section of the old alluvium, where the rainfall is generally less than 40 inches per year, irrigation on an extensive scale has been found necessary. The Upper Ganges Canal waters about 1,000,000 acres in the Upper Doab, while the Lower Ganges Canal is designed to water about 800,000 acres in the Lower Doab. In addition to these and other canals, there are hundreds of thousands of wells, and the natural depressions in the alluvial plain have also been utilised for the purpose of storing water. As a result, the population, amounting to 410 per square mile, is much larger than might have been expected. The principal food grains of the region are rice, which is grown with the aid of irrigation during the rains, on the heaviest soils ; wheat, which is a winter crop ; and bajra and juar, varieties of millet, which form the staple food of the people. Gram or chick pea and various oilseeds are also raised. Cotton is the most important fibre and covers about 3 per cent. of the cropped land, and sugar-cane occupies a like area. In the United Provinces, which may be taken as typical of the region under consideration, 66 per cent. of the population are dependent upon agriculture for their livelihood.
In the eastern section of the old alluvium, where the rainfall is greater, rice becomes the staple food of the population, and occupies about one-half of the cropped area. The rainfall has to be supple mented by irrigation, which is easy, as the broken surface of the land permits of the storage of water obtained by damming the smaller streams. The population of this region, which is about 490 to the square mile, is chiefly engaged in agriculture. Food crops (rice and the cereals of the previous region) are almost exclusively raised, but there is little or no surplus supply for export, and the people are, as a rule, poor.
In the third region—the recent alluvium—the surface of the land is generally level, the rainfall is great, and a considerable part of the country does not require artificial irrigation. Hence rice and jute constitute the staple crops, the two together occupying not less than 75 per cent. of the cropped area. Of these, jute is commercially the more important, as it provides the Bengal agri culturist with a surplus crop which he is able to sell, and his economic position is accordingly somewhat better than in the districts previously discussed. The density of population is greater than in any other part of the Ganges plain, being over 550 per square mile, and, outside of the towns, agriculture engages between 70 and 80 per cent. of the people.
The Brahmaputra valley north of the delta (along with which may be taken the upper part of its tributary, the Surma, and the intervening hills) has generally a rainfall of over 75 inches, and in the hill regions of over 100 inches. Rice is still the staple food of the people, but tea is the most important commercial product of the region. Formerly, it was grown mainly on the lower slopes of the hills, which were believed to be particularly adapted to it, but many of these situations have been abandoned in favour of reclaimed swamp lands, so that it is in the Brahmaputra and Surma valleys that the tea plantations of Assam and Eastern Bengal (covering about 700 square miles, or 85 per cent. of the Indian tea area) are now chiefly found. The heavy rainfall of these districts constitutes their chief advantage for the cultivation of the tea plant which grows best with an annual precipitation approaching 100 inches. The density of population in the Brahmaputra valley is low and does not exceed 100 to the square mile. This is due, partly to historical conditions, and partly to the fact that the land is not so suitable for the cultivation of rice as it is in the delta of Bengal. Agricultural operations are practically the only pursuit of the inhabitants.