There is no _à priori_ improbability that the Dravidian races of the south of India, or the indigenous races of the north, may not have erected temples or other buildings at a very early date, but if so, all that can be said is that all trace of them is lost. When we first meet the Buddhist style it is in its infancy--a wooden style painfully struggling into lithic forms--and we have no reason to suppose that the other styles were then more advanced. When, however, we first meet them, some six or seven centuries afterwards, they are so complete in all their details, and so truly lithic in their forms, that they have hitherto baffled all attempts to trace them back to their original types, either in the wood or brick work, from which they may have been derived. So completely, indeed, have all the earlier examples been obliterated, that it is now doubtful whether the missing links can ever be replaced. Still, as one single example of a Hindu temple dating before the Christian Era might solve the difficulty, we ought not to despair of such being found, while the central provinces of India remain so utterly unexplored as they now are. Where, under ordinary circumstances, we ought to look for them, would be among the ruins of the ancient cities which once crowded the valley of the Ganges; but there the ruthless Moslem or the careless Hindu have thoroughly obliterated all traces of any that may ever have existed. In the remote valleys of the Himalaya, or of Central India, there may, however, exist remains which will render the origin and progress of Hindu architecture as clear and as certain as that of the Buddhist; but till these are discovered, it is with the architecture of the Buddhist that our history naturally begins. Besides this, however, from the happy accident of the Buddhists very early adopting the mode of excavating their temples in the living rock, their remains are imperishably preserved to us, while it is only too probable that those of the Hindu, being in less durable forms, may have disappeared. The former, therefore, are easily classified and dated, while the origin of the latter, for the present, seems lost in the mist of the early ages of Indian arts. Meanwhile, the knowledge that the architectural history of India commences B.C. 250, and that all the monuments now known to us are Buddhist for at least five or six centuries after that time, are cardinal facts that cannot be too strongly insisted upon by those who wish to clear away a great deal of what has hitherto tended to render the subject obscure and unintelligible. CLASSIFICATION. For convenience of description it will probably be found expedient to classify the various objects of Buddhist art under the five following groups, though of course it is at times impossible to separate them entirely from one another, and sometimes two or more of them must be taken together as parts of one monument.