The dwelling places . . . had, no doubt, before the last desert sand finally buried them, been cleared by their inhabitants and others of everything that possessed intrinsic value. But much of what they left behind, though it could never tempt the treasure-seekers of succeeding ages, has acquired for us exceptional value . . . the shreds of silks and other woven fabrics; the tatters of antique rugs; the fragments of glass, metal and potteryware; the broken pieces of domestic and agricultural implements . . . which had safely rested in the sand-buried dwellings and their deposits of rubbish -these all help to bring vividly before our eyes details of ancient civilizations that without the preserving force of the desert would have been lost for ever.

Stein's enormous collections of finds furnish most of the material displayed and discussed in this book -objects as humble as a broken mousetrap and a preserved ball of still-blue wool, and as epoch-making as the earliest extant star chart and the Dunhuang Diamond Sutra, the oldest known printed book. It would be tempting to describe the course that made Stein the great pioneer of Asian Silk Road archaeology as one of the serendipities that the British Empire was apt to throw up. A Hungarian, he entered the employ of the India Office after studying Old Persian and Indology at Tubingen and ancient coins at the British Museum; he was to add other languages, although he never, to his enduring chagrin, mastered Chinese. But it was no accident, rather tenacity coupled with great physical courage and a formidable talent for logistics, that took the indefatigable Stein first to the long-abandoned ruined cities of the Taklamakan Desert, and eventually to Dunhuang and the "infinite riches in a little room" holed up in the Library Cave at Mogao.

Stein's expeditions were authorized and largely financed by the colonial Government of India and, later, the British Museum; but as the essay on "Aurel Stein, the British Museum and the India Office" makes entertainingly plain, his sponsors were generally several steps, if not many leagues, behind him. On December 20, 1907, for example, Maunde Thompson, then Director of the British Museum, reported to the Treasury that, bearing in mind the great success of Stein's first expedition to what was then known as Eastern Turkestan, the museum trustees were to invest in his second expedition to the tune of Pounds

2,000 - two-fifths of the cost -in return for a pro rata share of the finds. By the time the British Museum had finished deciding what would come out of whose departmental pocket, however, Stein -who had asked for the money back in February 1905 -had left for Khotan more than eighteen months previously. He was by this time halfway through the journey that would lead to the Library Cave.

The story of Stein's acquisition of thousands of manuscripts and paintings from the Daoist monk Wang Yuanlu has been well told -both by him, and more recently in Peter Hopkirk's Foreign Devils on the Silk Road. Stein's return to London in

1909, bringing a hundred crateloads to be stored and sifted in the British Museum, was a major scholarly event. Although the purchase was not Stein's first coup -his earlier exploration of the southern Taklamakan had unearthed tens of thousands of objects, all meticulously marked with their precise location and accompanied by detailed site maps and Stein's wonderful photographs -it was his most theatrical and most significant. The Dunhuang cache contained some of the earliest surviving Chinese paintings and complete books, so well preserved that the scrolls even retained their original silk ties. It was to transform Western understanding of Tang and pre-Tang China and make him, for a time, a celebrity among European archaeologists and Sinologists.

More durably, the Dunhuang purchase made Stein an officially designated villain in China, and Western archaeologists continued to be distrusted as pillagers; even as late as the 1980s, Deng Xiaoping refused to countenance international involvement in the protection of China's enormous cultural heritage. The resentment is understandable; yet, had it not been for Stein, and for the great French Sinologist Paul Pelliot, who arrived hard on his heels in Dunhuang and carried off more bundles of scrolls, much of this unique archive would no longer exist. Wang, the trove's self-styled guardian, sold Stein great bundles of scrolls for what Stein himself considered a trivial sum. But Wang, for whom much of the cave's content was a closed book, had already given away some objects to win favour with local officials; and, some time after the Chinese had been alerted to the immense value of the cache by Pelliot and finally ordered the transfer of what was left to Beijing, he still had material to sell to expeditions from Japan and Russia. Nor was Beijing in that turbulent period a safe repository; many documents quietly disappeared, some turning up in the collection of the education minister's father-in-law.

At a conference of conservators at Mogao earlier this year jointly sponsored by the Dunhuang Academy and the Getty Conservation Institute, I detected a notable softening of hostility, which is reflected also in the extensive Chinese collaboration in the British Library's Silk Road exhibition and accompanying catalogue. The Chinese may not be quite ready to admit it openly, but their leading scholars know that Stein saved -and, by depositing every item with British and Indian museums, preserved for scholarship -a priceless store of knowledge that would otherwise have been dispersed and, perhaps, destroyed.

In a fascinating essay in this volume, Mark Barnard and Frances Wood acknowledge that early British handling of the Dunhuang archive also fell short of perfection.