pioneer is again found, having pushed his way southward from the last village colony. As the country rises on to the plateau, so the steppes give place to open forest, and open forest to dense jungle of conifer, or to park-like stretches of larch forest, accompanied by vegetation of great beauty.[1] Here rivers run in all directions among an intricate maze of mountain masses and ranges. Some of these streams drain into the great Siberian rivers, while others sink away and dry up in the plateau districts to the south. It is along some 2000 miles of this type of country, from the upper waters of the Amur River in the Far East to the high plateaus of the Siberian Altai, that the political frontier between the Russian and Chinese empires has been roughly fixed in the past. It was along this artificial line that Siberian Cossack colonization in the north found a natural barrier against the Mongol tribes and the outposts of Chinese civilization in Asia. In the wild secluded spots of this frontier region one can still see the relics of a still more ancient civilization, which was compelled to retreat before the invasion of both Cossack and Mongol. Here in dense forest and on plateau steppe live the scattered tribes of nomad Finns and so-called Altai Tartars. Here, too, the Siberian frontiersmen have penetrated, as they have also done in the sub-Arctic forests and toundras of Northern Siberia. Some of them live for most of the year in the last communal villages on the Siberian side of the frontier, and from these, during autumn and early winter, they trek southward into the frontier country, where Siberia and Mongolia meet. Like their brethren in the north they spend the early
- ↑ See Map of Vegetation Zones of Western and Central Siberia.
