Its width, so far as eye can judge, does not greatly exceed that of the Thames at Gravesend, but it is always the same from the bridge at Twer above Moscow to the only other bridge, one mile in length, between Syzran and Samara; everywhere the same "full bumper" for a run of 2,000 English miles. Though the Volga is numbered among the European rivers, and has its sources on the Valdai hills between the European cities, St. Petersburg and Moscow, it is a frontier stream, and seemed intended to form the natural line of demarcation between two parts of the world--between two worlds. Up to the middle of the Sixteenth Century, Kasan was the advanced guard of the Tartar hordes. These wandering tribes, which, profiting by dissensions among the Russian princes, overcame and overran all Russia, weakened in their turn by division, fell back from the main part of the invaded territory, but still held for some time their own on the Volga, from Kasan to Astrakhan, till they were utterly routed and brought under Russian sway by Ivan the Terrible. Even then, however, though their strength was broken, their spirit was untamed. The men of high warrior caste who survived their defeat sought a refuge among their kindred tribes further east, at Samarkand, Bokhara, and Khiva, where the Russians have now overtaken them; but a large part of the mere multitude laid aside without giving up their arms, passively accepted without formally acknowledging the Tsar's sway, and abided in their tents,--swallowed at once, but very leisurely digested, by the all-absorbing Russian civilization. Large bodies of the nation, however, migrated _en masse_ from time to time, the lands they left vacant being rapidly filled up by bands of Cossacks, and by foreign (chiefly German), colonists. For more than three centuries, though already mistress of Siberia and victorious in remote Asia, Russia proper might be considered as ending at the Volga; so that most of the older and most important towns south of Kasan and north of Astrakhan, such as Simbirsk, Syzran, Volsk, Saratof, Kamyshin, and Tsaritzin, lie on the right, or Russo-European bank of the stream. Tsaritzin is at the head of the Delta of the Volga, and it lies 580 versts above Astrakhan, which is said to be at the river's mouth, but which is still 150 versts from the roadstead or anchorage, called the Nine Feet Station; the spot on the Caspian where sea navigation really begins. At Tsaritzin we might have fancied ourselves in some brand-new town in one of the remote backwoods of America. It was nothing of a place before the railway reached it. No one can foretell what it may become before the locomotive travels past it. For under present circumstances all the postal service, the light goods and time-saving passenger traffic from all parts of Russia to Astrakhan, the Caspian and the Trans-Caspian region, or _vice versa_, must pass between the Tsaritzin pier on the Volga and the platforms of the Tsaritzin railway station.