It was a fixed habit with the great buffalo herds to move southward from 200 to 400 miles at the approach of winter. Sometimes this movement was accomplished quietly and without any excitement, but at other times it was done with a rush, in which considerable distances would be gone over on the double quick. The advance of a herd was often very much like that of a big army, in a straggling line, from four to ten animals abreast. Sometimes the herd moved forward in a dense mass, and in consequence often came to grief in quicksands, alkali bogs, muddy crossings, and on treacherous ice. In such places thousands of buffaloes lost their lives, through those in the lead being forced into danger by pressure of the mass coming behind. In this manner, in the summer of 1867, over two thousand buffaloes, out of a herd of about four thousand, lost their lives in the quicksands of the Platte River, near Plum Creek, while attempting to cross. One winter, a herd of nearly a hundred buffaloes attempted to cross a lake called Lac-qui-parle, in Minnesota, upon the ice, which gave way, and drowned the entire herd. During the days of the buffalo it was a common thing for voyagers on the Missouri River to see buffaloes hopelessly mired in the quicksands or mud along the shore, either dead or dying, and to find their dead bodies floating down the river, or lodged on the upper ends of the islands and sand-bars. Such accidents as these: it may be repeated, were due to the great number of animals and the momentum of the moving mass. The forced marches of the great herds were like the flight of a routed army, in which helpless individuals were thrust into mortal peril by the irresistible force of the mass coming behind, which rushes blindly on after their leaders. In this way it was possible to decoy a herd toward a precipice and cause it to plunge over en masse, the leaders being thrust over by their followers, and all the rest following of their own free will, like the sheep who cheerfully leaped, one after another, through a hole in the side of a high bridge because their bell-wether did so.