In 1874-75, the Russian government sent a research and trading mission to China to seek out new overland routes to the Chinese market, report on prospects for increased commerce and locations for consulates and factories, and gather information about the Dungan Revolt then raging in parts of western China. Led by Lieutenant Colonel Iulian A. Sosnovskii of the army General Staff, the nine-man mission included a topographer, Captain Matusovskii; a scientific officer, Dr. Pavel Iakovlevich Piasetskii; Chinese and Russian interpreters; three non-commissioned Cossack soldiers; and the mission photographer, Adolf Erazmovich Boiarskii. The mission proceeded from Saint Petersburg to Shanghai via Ulan Bator (Mongolia), Beijing, and Tianjin, and then followed a route along the Yangtze River, along the Great Silk Road through the Hami oasis, to Lake Zaysan, back to Russia. Boiarskii took some 200 photographs, which constitute a unique resource for the study of China in this period. Most of the photographs are included in this album, which later became part of the Thereza Christina Maria Collection assembled by Emperor Pedro II of Brazil and given by him to the National Library of Brazil. Armillary spheres; Astronomical instruments; Astronomical observatories; Memory of the World