BIISK (Bnrsic), a town in the Siberian area of the Russian Socialist Federal Soviet Republic, situated at the point where the Ob river is formed by the junction of the Biya and the Katun. Lat. 52° 4o' N., long. 85° 4o' E. Pop. (1926) 45,574. It has stor age plant for butter and eggs and is the terminus of a caravan route from Kobdo in Mongolia. The Ob river is navigable to Biisk, and Siberian merchants dispatch their wool and skins by steamer as soon as the ice melts and in spring form caravans to go to Mongolia, taking with them manufactured goods and lump silver. Chinese brick tea is sometimes used as currency. The rate of ex change of silver and brick tea at Biisk is an interesting index of the relative prosperity of the Siberian area and Mongolia.