Almost on the banks of the river Bug, which used partly to separate Poland from Russia, between 51° 30' and 53° N. lat., there is a flat plain, the watercourses on which have too little fall to carry off the accumulated water. The whole plain is nearly a continuous swamp, and covered with fir-trees. It contains the sources of several effluents of the Dnieper and Vistula. On both sides of 52° N. lat. it extends from 24° to 30° E. long., a distance of 240 miles, and renders the country on both sides of the river Pripecz almost impassable. This portion of the Nvathrslied is called the Swamps of Pinsk and Ratner.
The swampy ground extends farther north, between the affluents of the Niemen and Dnieper, to 53° 30' N. lat., and terminates on the banks of the Dana between Polotak and Drooya. In these pnrta how ever the swamps are only from 100 to 50 miles in width, and are frequently interrupted by tracts of drier and more elevated land. East of the northern extremity of these swamps, between 54° 30' and 55' 30' N. lat., there is a more elevated country with a very broken surface, and containing numerous rocky hills, between which many lakes occur. From this elevated tract, which separates the upper courses of the riven Dnieper and Dena, the watershed extends northward over the eastern portions of the governments of Vitepsk and Pakow, where it descends in low ridges to the lakes of Peipus and Ilmen. The most elevated part of it probably attains 000 feet above the sea, as the town of Mojaisk on the Moskwa is more than 700 feet above it. The watershed hitherto noticed divides the rivers that flow into the Baltic from those which run into the Black Sea. At this point however it divides, and forms two watersheds, of which one runs noath-east between the waterconrses that fall into the White Sea and those which run into the Caspian Sea, and the other rune south-east between the rivers which flow to the Caspian and those which fall into the Black Sea.
The north-eastern watershed begins in the hilly region of Valdai, which contains the source of the Volga, the largest river of Europe. It lies contiguous to the region just described, beginning on the west between the sources of the river Pole, which falls into Lake Ilmen, and extending north-east to the river Mete. In this direction it occu pies hardly more than 90 miles, but extends from north-west to south east, between Novgorod and Vischnei-Volotshok, more than 120 miles. The country rimer from the north-west and sonth-east with a gradual elope, and at the town of Valdai attains an elevation of about S70 feet. On the moat elevated portion of It there are steep and rocky bilk, but of little elevation above their base; the highest of them, the Popowa Oora, according to Humboldt, does not exceed 934 feet above the sea.leveL As this region was formerly covered with a continuous forest, it Is also known by the name of the fond of Volkhonsk. From the banks of the river }iota the watershed extends northward towards the isthmus which divides the great lakes of Ladoga and Onega, but it does not reach it, as it turns again to the north-east, and remains about 20 or 25 miles from the southern extremity of Lake Onega, running between its banks and the Lake of halo (hero. Having
reused between these lakes, It sneldenly turns to the south, and approaches the banks of the Volga (40' F.. long.) within about 60 miles. Between the river 3Ista and 40' E. lame the watershed seems to be much lower than on the hilly region of Valdai, as is proved by the facility with which canals have been made across it to unite the rivers which fall into the Lake of Onega or into the Dwina with the affluents of the Volga. The more elevated tract, with its very gradual slopes, does not seem to exceed 20 miles in width, and Is entirely covered with forests. From 40' E. long. the watershed extends eastward near 59" N. lat., between the affluent.. of the Dwina and those of the Volga, to 50' F.. long., whence it declines to the north-east and reaches the Ural }fountains in 61' 30' N. let., 59' E. long., between the sources of the rivers Petechors and Kolva; the latter is a branch of the Kama, an affluent of the Volga. The whole region east of 40' E. long. is covered with interminable forests of pines and firs, and nearly uninhabited. This large tract of country is called by some geographers • uwelli: The south-eastern watershed begins likewise in the elevated hilly region which separates the upper counsel of the Dena and Dnieper, and rune for some distance close to the banks of the last-mentioned river, so that the river Moskwa, which originates in these parts, runs eastward to the Oka, an affluent of the Volga. It continues in • nearly southern course from 55' to 52' 30', and up to 53' 30' N. lat., seems to consist of a broad-backed swell, which is covered with forests. Between 53' 30' and 52' 30' N. lat, it expands in wide and nearly level plaina'which occupy perhaps 100 miles in breadth, and extend over the central provinces of Russia eastward up to the banks of the Volga, between 52' and 53' 30' N. lat. These plains do not probably rise more than 800 feet above the sea-level, and are chiefly woodiest, though in some of the numerous depressions trees of stunted growth are frequent. Where the watershed approaches the banks of the Volga, in the southern districts of the government of Simblrek, it forms an elevated ridge, but small In width, which rune eastward, and compels the river to make a bend at Samara (near 53' N. lat.). On the metals' bank of the river a similar ridge rises, which Indoors the river Sock, and continues in an eastern direction until it joins the Obstsbei Sirt, or western branch of the Ural Mountains, near 56' E. long. That portion of the ridge which lies east of the Volga con eiets of sandy hills almost without vegetation, and partaken largely of the nature of the steppes wbloh lie south of it. This watershed ineloses the wide basin of the upper course of the Volga on the south, and divides' it from the rivers which run southward and unite with the Dnieper and the Don.