478 RUSSIA for the number of its islands. Through the White sea, the Arctic ocean receives the Me- zen, the Dwina, and the Onega. On the de- clivity of the Baltic are the Tornea and the Kerai, which fall into the gulf of Bothnia; the Neva and the Narva, which fall into the gulf of Finland ; the Duna and the Aa, which flow into the gulf of Riga; and the Niemen, which rises in the government of Minsk, and before terminating its course enters Prussia under the name of the Memel. The Vistula, whose source and mouth belong to Austria and Prussia respectively, traverses Poland, and receives several tributaries, among which the Bug, rising in Galicia, Austria, is most impor- tant. To the basin .of the Black sea belong the Pruth and the Dniester, both rising in Ga- licia; the Bog, rising in Podolia; the Dnieper, which rises in the government of Smolensk, receives a considerable number of affluents, among them the Beresina, and falls into the Black sea near Kherson ; the Don, originating in the government of Tula, intersecting the Cossack country, and discharging into the sea of Azov; and the Kuban, which descends from the Caucasus, forms part of the boundary be- tween Asia and Europe, and near its mouth separates into two branches, one of which falls into the sea of Azov and the other into the Black sea. The basin of the Caspian sea re- ceives the Volga, the largest river of Europe, which rises in the government of Tver and dis- charges into the Caspian near Astrakhan, and the Ural, which descends from the eastern de- clivity of the mountains, traces out for some distance the frontier of Europe, and falls into the Caspian near Guriev. Most of the lakes of European Russia belong to the northern basins, as Lake Ladoga, the largest lake of Europe, and Lakes Onega, Peipus, and Ilmen. The government of Olonetz alone contains hundreds of smull lakes, and a still larger num- ber is found in Finland. European Russia in general forms part of an immense plain, be- ginning in Holland, and extending over the north of Germany and the whole east of Eu- rope. Only occasionally small table lands oc- cur, as the Valdai hills in the governments of Novgorod and Tver, the loftiest summit of which is about 1,150 ft. high. To the north- west some branches of the Scandinavian moun- tains enter the Russian territory. In the south- west the Carpathian mountains send forth slight ramifications. To the south, in the peninsula of the Crimea, is the insulated chain of the Yaila mountains, which in one place attain an elevation of about 5,000 ft. To the east the Ural mountains, and to the southeast the Caucasus, form in great part the natu- ral frontier between Europe and Asia. The plains are here and there covered with swamps, more frequently with forests; while in the southern parts of the empire they consist of dry and woodless tracts called steppes. The steppe region extends from the river Pruth, across the lower watercourses of the Dniester, Bog, Dnieper, and Don, as far as the Volga and Caspian sea. It is only in the western and middle parts of this region that rich mead- ow land is met with ; the rest is poorly wa- tered, thinly populated, and, notwithstanding the occasional fertility of the soil, but little favorable to agriculture. What the steppes are to the south and east of Russia, the tun- dras in the governments of Olonetz and Arch- angel, mostly toward the shores of the Arc- tic ocean, are to the north. They are tree- less wastes, bearing a scanty vegetation of low shrubs on a moss or turf surface. The geo- logical structure of European Russia is char- acterized by vastness and simplicity. Single formations are found to extend over entire provinces. In the northern part the granite and the Permian formation, composed of grits, marls, conglomerates, and limestones, prevail ; Esthonia and Ingria (government of St. Pe- tersburg) present the Silurian formation, rest- ing on schistose rocks. Along the chain of the Ural mountains, besides the eruptive for- mations of the most ancient period, the Silu- rian group prevails. Lithuania and Poland belong almost wholly to the tertiary group ; they also contain cretaceous rocks. The south- ern portion of European Russia belongs to the tertiary and granitic groups. The south- ern coast of the Crimea is of Jurassic forma- tion. In the Caucasian countries cretaceous and Jurassic rocks prevail, mixed with gran- ite. The quality of the soil differs very great- ly in the different provinces. Some consist mostly of sandy barren plains or vast morass- es. The most valuable portion of the empire is that south of the Valdai hills and of Mos- cow, extending on the east to the Volga, and including the country of the Don almost as far as the sea of Azov, and on the west to the frontier of Galicia. All this region is rich wheat land, exporting wheat to Asia and Eu- rope, through Odessa, Nikolayev, Taganrog, and Kertch. Almost the whole of European and three fourths of Asiatic Russia lie within the temperate zone. The southern border of the empire approaches to within 15 of the tropic zone, while the northern border extends 11 beyond the arctic circle. In general the climate is severe. The mean temperature of winter passes the freezing point even in the most southern districts. South of lat. 58 the mean temperature is between 40 and 55 F. ; the winters are long and severe, and the sum- mers short and hot. With lat. 58 the cold region begins, and with lat. 65 the arctic re- gion. At St. Petersburg, which is within the former space, the thermometer in December and January sinks to 20 or 30 below zero, and exceptionally much lower, while in the summer it rises to 85 or 90. Among the most common atmospheric phenomena, in the steppes as well as in the northern provinces and in Siberia, is the luran, a vehement wind accompanied by heavy falls of snow. The central part is also subject to violent snow
