A fourth stage was reached in that shown in the next woodcut (No. 32), from a representation of a rail in the Gautamiputra cave at Nassick, A.D. 312 to 333, where there are three full discs on the pillars as well as on the rails, and no doubt other variations may yet be found; but these are sufficient to show how the discs were multiplied till the pillars almost become evanescent quantities in the composition. The greatest innovation, however, that took place, was the substitution of figure-sculpture for the lotus or water leaves of the discs, if that can be called an innovation, which certainly took place in the wooden age of architecture, before it was thought of translating these things into stone. The earliest rails we know, those at Buddh Gaya and Bharhut, show these changes already completed in the manner above described. The plainness of the rail, or the absence of figure-sculpture, is consequently no test of its greater or less antiquity, though the extreme multiplication of discs, as shown in the last example, seems only to have taken place just before their discontinuance. * * * * * To return, however, from this digression. The rail that surrounds the great tope at Sanchi was probably commenced immediately after its erection, which, as explained above, was probably in Asoka’s time, B.C. 250; but as each rail, as shown by the inscription on it, was the gift of a different individual,[124] it may have taken 100 or 150 years to erect. The age of the torans is more easily ascertained. There is an inscription on the south gateway, which is certainly integral, which states that the gateway was erected during the reign of a Sat Karni king, and it is nearly certain that this applies to a king of that name who reigned A.D. 10 to 28. As this gateway is certainly the oldest of the four, it gives us a starting-point from which to determine the age of the others. The next that was erected was the northern. That was followed by the eastern--the one of which there is a cast at South Kensington--and the last erected was the western. The style and details of all those show a succession and a progress that could hardly have taken place in less than a century, and, with other reasons, enable us to assert without much hesitation, that the four gateways were added to the rail of the great tope during the first century of the Christian Era, and their execution spread pretty evenly over that period.[125] The northern gateway is shown in the general view of the building (Woodcut No. 10), but more in detail in the cut (No. 33) on the following page.