The name River Bed is given to the entire breadth of the hollow which holds the river, and which varies in width according to the stage of the water, especially in large streams like the great rivers of America. The Mississippi is a mile wide at Natchez at low water, at high water almost thirty. The Orinoco, at St. Thomas, is three miles wide at low water, at high water it is over seventy. In the Volga and the Danube the stage of water makes great differences in the width of the river bed. In summer the depth and breadth are, as a rule, less than in winter. The Channel differs from the river bed; it is the part of the river bed which gives life and motion to the whole current. In the upper course the channel and the river bed generally coincide; in the middle and lower courses, on the contrary, the channel occupies but a very small share of the whole bed, but yet it determines the direction, amount of fall, and the rapidity of the stream. It lies usually not in the middle of the river bed, but on one side; it passes, however, from bank to bank; it is indicated by the movement of ships, which always follow it, and it lies uniformly adjacent to the boldest shore. It widens the whole river bed toward one side, and not toward both; and so streams which traverse great plains, like the great Hungarian one, for instance, do not now run through the middle, but course along at the base of the marginal bluffs. In all such cases, it will be found that the channel hugs the boldest side of the bed. All the four Carpathian rivers, as they wind out between the main range and the subordinate ranges, have their steepest shore, not on the side of the loftiest, but on the side of the boldest mountains, and these are the ones of the subordinate range. So, in the plains which lie between the Swiss Alps and the Jura, the bold sides of the river bed lie on the side of the bolder though less important chain, and not on the side of the Alpine meadows. The bold banks of the Ebro are not on the side of the Pyrenees and their plains, but on the south side. All the streams of South and Middle Russia have, therefore, on the east side, their low banks, on the west the bold ones; and this, because the most extensive plains lie on the eastern side.