Their great interest, therefore, from a historical point of view, consists in their being almost unique specimens of the architecture and arts of India during the great Gupta period, when Theodosius II. was emperor of the East, and at a time when Bahram Gaur, the Sassanian, is said to have visited India. He reigned 420 to 440; if he did visit India, it must have been while they were in course of being excavated.[192] Nos. 18, 19, and 20 succeed this group, both in position and in style, and probably occupied the remaining half of the 5th century in construction, bringing down our history to about A.D. 500. Before proceeding further in this direction, the cave-diggers seem to have turned back and excavated Nos. 8, 7, and 6. The last named is the only two-storeyed cave at Ajunta, and would be very interesting if it were not so fearfully ruined by damp and decay, owing to the faulty nature of the rock in which it is excavated. No. 7 has a singularly elegant verandah, broken by two projecting pavilions.[193] Internally, it is small, and occupied by a whole pantheon of Buddhas. It resembles, in fact, in almost every respect, No. 17 at Nassick, with which it is, no doubt, contemporary. There still remain the five first caves at the northern end, and the six last at the southern: one of these is a chaitya, the other ten are viharas of greater or less dimensions. Some are only commenced, and two, Nos. 4 and 24, which were intended to have been the finest of the series, are left in a very incomplete state: interesting, however, as showing the whole process of an excavation from its commencement to its completion. Both these were intended to be 28-pillared caves, and the hall of No. 4 measures 84 ft. by 89 ft. Caves Nos. 1 and 2 are among the most richly-sculptured of the caves. The façade, indeed, of No. 1 is the most elaborate and beautiful of its class at Ajunta, and with the corresponding caves at the opposite end conveys a higher idea of the perfection to which decorative sculpture had attained at that age than anything else at Ajunta. With the last chaitya, which belongs to this group, these caves carry our history down certainly into the 7th century. The work in the unfinished caves, I fancy, must have been arrested by the troubles which took place in Central India about the year 650, or shortly afterwards, when, I fancy, the persecution of the Buddhists commenced, and after which it is hardly probable that any community of that faith would have leisure or means to carry out any works, on such a scale at least, as these Ajunta viharas. * * * * *