Captain Lewis considered that this method of traveling was too dangerous, and he ordered the rest of the party to wade the river at the foot of the bluff, where the water was only breast-high. This adventure taught them the danger of crossing the slippery heights above the stream, but as the plains were broken by ravines almost as difficult to pass, they kept on down the river, sometimes wading in the mud of the low grounds, sometimes in the water, but when that became too deep, cutting footholds in the river bank with their knives. On that particular day they traveled through rain, mud, and water for eighteen miles, and at night camped in a deserted Indian lodge built of sticks. Here they cooked part of the six deer they had killed in the day's traveling, and slept on willow boughs they piled inside the lodge. Many of the party thought that the north fork was the Missouri River, but Lewis and Clark were both convinced that the south fork was the real Missouri. They therefore hid their heaviest boat and all the supplies they could spare, and prepared to push on with as little burden as possible. A few days later Lewis was proved to be right in his judgment of the south fork, for on June 13th he came to the Great Falls of the Missouri. The grandeur of the falls made a tremendous impression on them all. The river, three hundred yards wide, was shut in by steep cliffs, and for ninety yards from the left cliff the water fell in a smooth sheet over a precipice of eighty feet. The rest of the river shot forward with greater force, and, being broken by projecting rocks, sent clouds of foam into the air. As the water struck the basin below the falls it beat furiously against the ledge of rocks that extended across the river, and Lewis found that for three miles below the stream was one line of rapids and cascades, overhung by bluffs. Five miles above the first falls the whole river was blocked by one straight shelf of rock, over which the water ran in an even sheet, a majestic sight. This part of the Missouri, however, offered great difficulties to their travel. The men had now journeyed constantly for several months, and were in a region of steep falls and rapids. It was clear that they could not carry the boats on their shoulders for long distances. Fortunately they found a small creek at the foot of the falls, and by this they were able to reach the highlands. From there Lieutenant Clark and a few men surveyed the trail they were to follow, while others hunted and prepared stores of dried meat, and the carpenter built a carriage to transport the boats. They found a large cottonwood tree, about twenty-two inches in diameter, which provided them with the carriage wheels. They decided to leave one of their boats behind, and use its mast for two axle-trees.