Bearing a collector's seal: Pin Fang Shan Fang Qian Yin
The frontispiece signed: Chen, Liu Wengao Jincheng
Liu Wengao was a native of Zaoqiang who passed the Imperial examination in the gengxu eighth year of the Kangxi era (1730), having gained an examination position of two hundred and sixty-fourth with third class honours. (see Mingqing Jinshi timing Beilu Suoyin, Shanghai Guji Chubanshe, 1979, vol.3, pp.1960, 2701)
Jinshajiang is the upper reaches of the Yangzi River, running from Yunan through to Sichuan. It was proposed in the fourth year of the Qianlong era (1739) that this river be excavated to ease transportation, such that copper can be mined in Yunnan and transported by water to Sichuan. In 1740, the Emperor Qianlong ordered for reconnaissance along the river. When Governor General of Yunan, Qingfu, was transferred, he was succeeded by Zhang Yunsui, who carried out the investigatory reconnaissance along the entire length of Jinshajiang. In 1742, Zhang reported to the Emperor Qianlong with his findings, and was commanded to proceed with the dredging project.
It is no coincidence that for all the good intention of easing transportation, there had for many year been small revolts in Yunnan and Sichuan from ethnic minorities and religious cults. An efficient waterway would obviously afford the military easy access to different areas previously difficult to reach.
In 1746, Zhang reported to court that on completion of the project, the transportation of copper from Yunan to Sichuan reached some six million five hundred thousand catties, and the journey is efficient and smooth. While the project was reputed to have cost over one hundred thousand taels of gold, the ease in transporting some eight or nine million catties of copper saves around five million taels of gold between the fourth and eleventh year of the Qianlong era. (see Qingshi Biannian, Zhongguo Renmin Daxue Chubanshe, 1991, vol.5, pp.38, 73, 98, 114, 145, 237)
The present scroll is a detailed map of the entire length of Jinshajiang, specifically pointing out the way of the river and where dangerous points are located. Small inscriptions in the scroll explain where each bay is, and the work proposed. Suggestions include the building of copper warehouses. This scroll must have been painted as a result of the reconnaissanse carried out by Zhang Yunsui in 1742. Liu Wengao was an official of the same period. While it is very likely that he would have been on the expedition with Zhang, whether he actually painted the scroll is still to be investigated.
While the scroll is a geological survey, the painting is extremely fine. The depictions of water alone varies greatly along the scroll, and it can be seen that great effort has been made in not only rendering this geographically accurate but also that aesthetics was also taken into consideration by the artist. The scroll is some seventy-two metres (over two hundred and thirty feet) long and must rank as one of the foremost surviving masterpiece commissioned by Imperial command.
For brief biography of Zhang Yunsui, see Zhongguo Lidai Renming Dacidian, Shanghai Guji Chubanshe, 1999, p.1256
For brief biography of Gu Ao, see Zhongguo Jinxiandai Renwu Minghao Dacidian, Zhejiang Guji Chubanshe, 1993, .p.729