Taking stock of the past

Some slips are actually contracts, recording debits and credits. According to Xiao, people often wrote the details two times on a slip, witnessed by a third person. Then they carved a symbol representing the amount of money mentioned in the contract on the slip (at that time there were different symbols denoting numbers), and cut the slip into two halves, dividing the symbol as well. The debtor and creditor each possessed a half respectively. In this way, when conflicts occurred, they could match the two parts to check the complete agreement, and the carving ensured no one could change the amount of money written in the contract.

Juyan is not the only place in Gansu where such slips have been found. The Gansu Jiandu Museum also collects a large number of slips found in other places like Xuanquanzhi, which used to be a postal station in the Han Dynasty.

According to Xiao, the slips have been preserved to this day because of the dry and unchanging climate in Gansu. "They are not easy to preserve for such a long time unless in a stable environment, either very dry or very moist," says Xiao, who also mentions that the Gansu slips are now preserved in vacuum-sealed glass tubes in the museum.

Chinese philologists Wang Guowei and Luo Zhenyu published Liusha Zhuijian (Fallen Slips Buried in the Flowing Sands) in 1914, a book on the wooden slips found by British explorer Marc Aurel Stein in Northwest China. Since then, bamboo and wooden slips have become an increasing object of focus for Chinese and international scholars.

Juyan slips have been regarded as one of the four great discoveries in ancient literature of the early 20th century in China. Study on Juyan slips has been carried out for decades.

"At first, scholars focused on categorizing them, taking photos of them and identifying the words on them. Later, a document management perspective was introduced to study them, which focused on the nature and function of the slips," Xiao says. "In recent years, studies on the calligraphy of the slips, and the evolution of Chinese characters in them have also been popular."