The map presented here is centered on Lake Baikal and the major rivers that flow into or out of its watershed, including the Lena, Argun, Selenga, and Angara. It also shows the adjoining parts of eastern Siberia through which these rivers flow, and indicates tributaries, mountains, and vegetation. The map covers the Ust-Ilimsk, Irkutsk, Selenga, Yakutsk, and Nerchinsk Districts, all shown with yellow shading and delineated by yellow boundary lines. The largest regional cities and towns are indicated. Olkhon Island, the largest island in Lake Baikal, is also visible. Northern parts of Imperial China are shown at the bottom of the map and are set off from Siberia by a conjoined yellow-and-green line. Russian areas to the west, such as parts of the Krasnoyarsk and Yeniseysk Districts, are distinguished by pink shading and a pink boundary line. The map was compiled by Johann Treskot (1719–86), a cartographer of British descent, and engraved by A. Medvedev. Treskot was a talented geodesist who was affiliated with the Geographical Department of the Russian Academy of Sciences. The scale of the map is 42 kilometers per centimeter. It indicates distance in versts, a tsarist-era unit of length equal to 1.07 kilometers. An inset in the upper-right-hand corner lists Lake Baikal and the Lena, Argun, Selenga, and Angara Rivers as the main regions shown on the map and gives the name of the compiler.