Conservation as a profession faces many conundrums relating to choices about treatment, storage, or intervention. Such was the case recently when the GCI was asked to advise on the storage and handling of a significant collection in Tibet of thangkas—textiles that epitomize Tibetan religious art and that serve as a rich source of Buddhist iconographical information.
Hung in temples and homes or carried by monks in procession, thangkas have an important function in meditation and devotion. Typically they include images of the Buddha, representations of the Buddhist wheel of life, and mandalas, or horoscopes, used for prophecy.
Thangkas first appeared in about the 10th century, some 200 years after Buddhism arrived in Tibet. Traditionally painted on cloth, thangkas are also embroidered, woven, or appliquéd. A fabric border, often of silk brocade, surrounds the cloth panel. There is a small dowel at the top for hanging and a larger dowel at the bottom, the ends of which are usually capped with metal or ivory knobs.
The GCI's guidance was requested on the storage of a collection of thangkas housed in the Potala, the traditional home of the Dalai Lama, in the city of Lhasa. Vast and awe inspiring, the Potala dominates Lhasa, at 12,000 feet the highest capital in the world. Inscribed on the World Heritage List in 1994, the labyrinthine complex houses thousands of religious texts, scrolls, and artifacts.
The thangka collection, one of the many glories of the Potala, includes some 6,000 items. Although a few of the thangkas date to the 12th century, most are from the last 200 to 250 years; many are in good condition, with their colors still vibrant. While significant collections of ancient and historic horoscopes are found elsewhere—notably in China and in museums in the West—the most important collection in the world may be that of the Potala.
The question that faced the GCI staff invited to examine the collection's storage was whether to recommend that the traditional Tibetan wood and leather chests that have been used for storing the thangkas be replaced by modern metal cabinets. The chests, some with exterior decoration, have themselves become part of history. However, the storage method of tightly rolling the thangkas and packing them into these chests is detrimental to long-term preservation. The tight rolling results in some stress on all types of thangkas, but the painted thangkas are most seriously affected; the paint layer is prone to cracking and flaking as a result of repeated rolling.
At present, the rolled thangkas are stacked upon one another in chest after chest. Given the long history of the collection, its high religious and artistic values, and the fact that some representations are not found in other thangka collections, Potala staff anticipate an increasing demand for research access. Exhibition would be limited, although some thangkas are always hung in shrines in the Potala.
Concerns regarding the suitability of using modern steel cabinets instead of the traditional chests centered on several issues: loss of the traditional storage method; the visual intrusion of metal cabinets in a historic building that continues, in some respects, its traditional functions; the trunks as a part of the history of the collection; and the weight of the metal units on an uneven floor of rammed earth.
The recommendation of GCI staff was that the fragile, painted thangkas be stored flat in museum-quality metal cabinets. Ideally, all of the thangkas should be stored this way. However, flat storage is not feasible for the particularly large thangkas, nor is it practical for the remainder of the collection, in view of the sheer numbers of thangkas. GCI staff further recommended that, where practical, flat storage be introduced in stages and also that consideration be given to modifying the traditional chests with removable spacers to prevent contact.
Much needs to be done, including comprehensive documentation, to safeguard the thangka collection and other treasures of the Potala. Fortunately, the dedicated staff are now receiving help and advice from other institutions, such as the Tibet Museum (which itself has a significant thangka collection) and the Palace Museum in Beijing. The GCI was pleased to play an advisory role in one aspect of the effort to preserve Tibetan heritage.