A few miles farther, as they passed a precipice a hundred and twenty feet high, they saw evidence of the cunning and wasteful methods of hunting by Indians, for the remains of over a hundred buffalo were scattered around, though the stream must have washed many away. Lewis adds: "These buffaloes had been chased down the precipice in a way very common on the Missouri, and by which vast herds are destroyed in a moment. The mode of hunting is to select one of the most active and fleet young men, who is disguised in a buffalo skin round his body. The skin of the head, with the ears and horns, are fastened on his own head in such a way as to deceive the buffalo. Thus dressed he fixes himself at a convenient distance between a herd of buffalo and any of the river precipices, which sometimes extend for several miles. His companions, in the meantime, get in the rear and side of the herd, and at a given signal show themselves and advance toward the buffalo. They instantly take the alarm, and finding the hunters beside them they run toward the disguised Indian or decoy, who leads them on at full speed toward the river, when suddenly securing himself in some crevice of the cliff, which he had previously fixed on, the herd is left on the brink of the precipice. It is then in vain for the foremost to retreat or even to stop; they are pressed on by the hindmost ranks, who, seeing no danger but from the hunters, goad on those before them till the whole are precipitated and the shore is strewed with their dead bodies. Sometimes in this perilous seduction the Indian himself is either trodden under foot or, missing his footing in the cliff, is urged down the precipice by the falling herd." The river now took the form of frequent rapids, which made the work of dragging the heavy canoes very painful, and the narrative runs: "The banks are so slippery in some places, and the mud so adhesive, that the men are unable to wear moccasins. One-fourth of the time they are obliged to be up to their arm-pits in the cold water, and sometimes walk for yards over sharp fragments of rocks." On June 3d they came to where the river divided into two large streams, and it became of vital importance to the expedition to determine which was the Missouri or Ahmateahza, as the Minnetarees called it, and which they said approached very near to the Columbia. The success of the expedition depended on the right decision, so Captain Lewis concluded to encamp until reconnoitering columns could examine the two forks. Lewis following up the north branch, two days' march, decided that it was not the Missouri, and named it Maria's River. In returning he narrowly escaped slipping over a precipice some ninety feet high. Lewis had just reached a spot of safety when, says the narrative,