(7) _Castes formed by changes of custom._ This is a fruitful cause of new divisions of Hindu society. It is, for the moment, more than usually operative, owing to the spread of education, and often represents a difference of social opinion which corresponds, more or less closely, to Conservative and Radical ideas among ourselves. It evidently was always a cause of fissiparous tendencies. The most notable instance is the distinction between Jāts and Rājputs, both apparently sprung from the same stock, but separated socially, amongst other causes, by the fact that the former practise and the latter abjure infant marriages. * * * * * This is a very rapid and highly summarised account of the races and castes of India. There are many obvious omissions. Nothing has been said of the Sikhs, little or nothing about the numerous races of the north-eastern frontier. But enough has been said to give a fair general impression of what the physical characters of the Indian peoples are, and what kind of institution caste is in its practical working. More might have been said about totemistic clans, but on this subject those who would pursue their studies further have only to turn to Dr J. G. Frazer's work on the subject. In the next chapter, I have to borrow my materials from Sir G. A. Grierson, and show how the peoples of India are divided by differences of language. On the whole, those linguistic divisions correspond with remarkable accuracy to the orographical and climatic structure of the country and the racial divisions which we owe to the learning and ingenuity of Sir H. H. Risley. Where there are great open plains, watered and fertilised by mighty rivers, we get large populations speaking the great literary languages of India. In the rugged recesses of the mountains we find small communities, divided from one another by physical obstacles which have produced rigid local patriotisms and enmities, and a wonderful variety of savage speeches. The linguist has usually worked independently of the ethnologist, and has come to his own unprejudiced conclusions. It is interesting to find how closely the results of their separate enquiries agree. _Postscript._