In the last thirty years a remarkable and quite the most important feature of Indian history has been the rapid growth and extension of Hinduism. Yet, so easy and natural has it been, it has passed almost unnoticed. There are many in Europe who believe that Indian castes are fixed, immanent, and immutable. And this belief is upheld with conviction by almost every Indian. Yet nothing could be more erroneous. The concept of caste is no doubt ancient and of a strength so confirmed that it can almost with propriety be called permanent. Yet the actual castes--the things that _are_--are fluid in the extreme and are in constant movement, while the boundaries of the system have recently had vast extensions. The ease of communication given by railways has brought the central Brahman influences home to every hamlet in the continent, till whole tribes that were formerly hostile have been persuaded to adopt the name and many of the customs of the Hindu. At the same time new thoughts of Indian nationality and solidarity, born of English education, have roused in the higher and educated classes a real desire to comprise within the Hindu fold peoples from whom their fathers would have shrunk as from foreign and debased savages. But the idea round which the whole caste system revolves is that of marriage. Far above the maintenance of ceremonial purity, far above mere restrictions on food and water, stands, as the one essential rule of caste, the limitation of lawful marriage to a fixed circle of descent, real or fanciful. And with this limitation, which is of the very essence of Hinduism, goes a certain view of marriage as magical, sacramental. Thus each additional conversion of a strange tribe to the Hindu system brings fresh adherents in great numbers to what, more or less clearly adumbrated, is at least a reflection of the Brahman ideal of womanhood. To coarser minds and to tribes not much advanced beyond the savage, only a thin ray of the ideal can penetrate. Among such tribes the woman may remain free for some long time from the trammels of the higher law. [Illustration: CAMBAY TYPE] For that law can be tolerable only when it is fully comprehended. But as they advance in civilization and the conversion to Hinduism is solidified, as it were, by developing education, so the ideal, more and more clearly grasped, begins to be followed in practice. It is at this stage that child-marriage and the unrelieved doom of widowhood are introduced. New India therefore presents the paradox that while in the upper class a few, gained to the cause of rationalism, allow widows to remarry, discarding almost with violence the old sanctions and the old beliefs, side by side in the great mass of the people the prejudice daily grows and millions now forbid remarriage who thirty years ago would never have dreamt of the restriction.