MISSISSIPPI RIVER (ante). The sources of this great river are lakes Itasca, Travers or Petnidgi, Cass, Winnehigoshish, Fishing, Leech, and Mud, lying among hills of drift and bowlders, in the'midst of pine forests and marshes. From lake Itasca to Travers the stream is about 12 ft. wide and 2 ft. deep. It issues from the latter 120 ft. wide to Cass lake, which it leaves with a width of 172 ft., contracting and deepening below as it flows through marshes till it comes to a junction with Leech river, where it has rapids of 20 ft., called the falls of Pecagama, 270 m. from the source. To this point small steamers navigate. The total descent to this point is 324 feet. Thence to the mouth of Pine river, about 200 m., the river falls 165 ft.; thence to Crow-wing river 47 m., one ft. per mile. The river is narrow through this distance and winds through oak and maple forests, marshes, and sandy hills, where the natural formation of rock is overlaid with the gravel and bowlders of the drift period. Below, the river passes through a prairie country down to Elk river. and is stained slightly with the brownish color given by piney and marshy vegetation; 133 m. below the Crow-wing are the Sauk rapids one m. long, Where the first regular formation of rock is seen on its banks. This is of the Potsdam sandstone, which extends from that point down to Dubuque and Rock Island. The falls of St. Anthony at 3Iinneapolis are only 1S ft., with a breadth of 1200. Up to this point the river is navigable for commercial purposes, widening below from what is called lake Pepin, ninny islands: From above the falls of St Anthony to the junction with therlrissouti, the river flows through a valley of great beauty and fertility. Cliffs and rocky bluffs, from 200 to 300 ft. high, give a picturesque character to that part of the valley below Rock Island, where its strikes the carboniferous strata, the geological formation of the valley, to about 100 in. below the Missouri. At Rock Island, 350 in. below St. Anthony, there is,a fall of 22 ft., and the Des Moines rapids, 475 in. below St, Anthony's, have a tall of 24 ft. The government has constructed ship canals around these rapids, so that the navigation of the upper Mississippi is uninterrupted below the falls of St. Anthony. The junction of the Missouri is like the marriage of a rough impetuous uncouth man with a refined and graceful woman. The surging, muddy, eddying waters of the greater stream, the Missouri, for a long distance flow side by side with the clear waters. of the Mississippi, joining but not blending, ,till tin own together by many a crook and turn and eddy between the bluffs of the great valley. Before the Ohio river joins, the union is complete; but the waters remain turbid to their junction with the sea, and, where joined by the currents of the Arkansas and Red rivers, take a more reddish color. Three m. above cape Girardean and about al m. above the mouth of the Ohio, the river begins to have a surface above much of the adjacent land; and for 1300 us. to the sea it flows over a vast alluvial deposit of its own creation, below
the surface of which its tortuous bed is deeply cut, while the top of ils current is higher than the land.
The mean annual velocity of the current below the junction of the Missouri is 3.29 ft. per second—about 24 m. an hour. The average annual rain-fall in its basin is estimated at 30.4 iu.; and the yearly discharge of water into the gulf of Mexico at 145 cubic miles. The depth of the channel below the mouth of the Ohio is from 75 to upward of 100 feet. The variation from lowest to highest water at Natchez. Vicksburg, and Cairo was formerly 52 ft., but is supposed to have been reduced to 46 ft. by new channels and levees. The sediment contained in the water below the Missouri is .0035 of its volume. The area of the delta of the river is estimated at 38,600 sq. miles. The entire valley of the river is margined by deltas, and considerable parts of Louisiana, Mississippi, and Arkansas are all delta. The bottom-lands above.cape Girardeau, which are occasionally overflowed, but which are clearly above the level of the river at ordinary stages, are to be distinguished from those large tracts adjoining the lower part which lie below the surface of the river at all seasons.. The former are almost continuous on ene side of the river or the other, and generally on both sides, from the falls of St. Anthony to three in. below cape Girardeau, where the surface is so low as to be subject to over flow in all seasons, save where defended by levees. These bottom-lands, both high and low, are of the highest order of fertility; those farthest north being used for corn (maize) principally, and tor tobacco and pasturage. Some of the largest have been reclaimed from liability to overflow by dikes across the water-channels by which they were inundated. any island in Pike co., Illinois, so reclaimed, is 40 m. in length. The American bottom extends from the mouth of the Missouri 90 m. down the river, with an average breadth of 6 miles. Below cape Girardeau (about 30 m. above the mouth of the Ohio), on the w. side, the whole country down to the gulf is mostly delta for an average width of 50 m.; and in high floods the river formerly overflowed nearly all the surface between the mouth of the Ohio and the St. Francis rivers in s.e. Miesouri and eastern Arkansas, filling the lakes and lagoons of that region, and then flowing by numberless channels to the White river and Arkansas valleys, the bayou Macon, "Washita, Red and Atchafalaya rivers into the gulf. This region is made safe from floods and habitable only by levees. The Louisiana delta has been for a hundred tears to a. considerable extent reclaimed by levees. The great delta on the cast side, embracing the whole area between the Mississippi and the Yazoo, about CO in. in width, has been partially protected for about 50 years, while the protection of the upper portion above Memphis is a more recent undertaking.