So far as our manuscripts are concerned, the first half of the ninth s century yields an almost complete blank. To judge by the absence of any dated text during forty-five years, the Tibetan rulers were not favourable either to orthodox Buddhism or to any form of literary activity. At any rate, a remarkable revival took place immediately after the revolution of Chang I-ch’ao, and the number of dated documents for the second half of the century is actually larger than for any previous period of the same length. It is true that the proportion of sutras and other Buddhist texts has now shrunk considerably. In their place we find miscellaneous documents of many kinds—letters and reports, circulars and account notes, calendars and didactic treatises, mostly in a fragmentary state. The most important feature, however, is the first appearance of printing, of which there are three specimens, dating from 868, 877, and 882 respectively. The first of these is the world-famous copy of the Diamond Sutra with its well-designed frontispiece, printed from blocks in so masterly a fashion as to make it evident that the art of printing must already have been practised in China for a considerable time.