File:Six Strongmen In Traditional Dress, China.jpg
William Purdom (1880-1921) was another explorer botanist that surveyed and collected northern Chinese flora along the Yellow River for three years, from 1909-1911; and in Tibet and Gansu, from 1914-1915.
The original non-restored picture was discovered in Harvard University's Library Collection using their VIA (Visual Information Access) Search engine. It can be found with Record Identifier: olvwork270371. Other information included stated:
"...Strong men at August games (Mongol). Photo by Wm. Purdom, 1909-1911. Weichang Xian, Hebei Sheng, China" (Note: located in today's 围场满族蒙古族自治县, a ethnic autonomous county in Hebei bordering Inner Mongolia)