Be this as it may, any one who will compare the plan of the chaitya at Sanchi (Woodcut No. 40), which is certainly Buddhist, with that of this temple at Aiwulli, which is either Jaina or Vaishnava, can hardly fail to perceive how nearly identical they must have been when complete. In both instances, it will be observed, the apse is solid, and it appears that this always was the case in structural free-standing chaityas. At least, in all the rock-cut examples, so far as is known, the pillars round the apse are different from those that separate the nave from the aisles; they never have capitals or bases, and are mere plain makeshifts. From the nature of their situation in the rock, light could not be admitted to the aisle behind the apse from the outside, but must be borrowed from the front, and a solid apse was consequently inadmissible; but in free-standing examples, as at Aiwulli, it was easy to introduce windows there or anywhere. Another change was necessary when, from an apse sheltering a relic-shrine, it became a cell containing an image of a god; a door was then indispensable, and also a thickening of the wall when it was necessary it should bear a tower or sikra to mark the position of the cella on the outside. Omitting the verandah, the other changes introduced between the erection of these two examples are only such as were required to adapt the points of support in the temple to carry a heavy stone roof, instead of the light wooden superstructure of the Buddhist chaitya. (Woodcut No. 121.) [Illustration: 121. Temple at Aiwulli. (From a Photograph.)] It may be a question, and one not easy to settle in the present state of our knowledge, whether the Buddhist chaityas had or had not verandahs, like the Aiwulli example. The rock-cut examples naturally give us no information on this subject, but the presumption certainly is, looking at their extreme appropriateness in that climate, that they had this appendage, sometimes at least, if not always. If from this temple at Aiwulli we pass to the neighbouring one at Pittadkul, built probably a couple of centuries later, we find that we have passed the boundary line that separates the ancient from the mediæval architecture of India, in so far at least as plans are concerned (Woodcut No. 122). The circular forms of the Buddhists have entirely disappeared, and the cell has become the base of a square tower, as it remained ever afterwards. The nave of the chaitya has become a well defined mantapa or porch in front of, but distinct from, the cell, and these two features in an infinite variety of forms, and with various subordinate adjuncts, are the essential elements of the plans of the Jaina and Hindu temples of all the subsequent ages. [Illustration: 122. Plan of Temple at Pittadkul. (From a Plan by Mr. Burgess.) Scale 50 ft. to 1 in.]