How interesting it must have been to push into the Rocky Mountains, beyond the farthest point previously reached by white men; to see Nature in her wild state, to note the new plants and animals, and to study the Indians before their contact with Europeans had changed their customs! Lewis and Clark were particularly instructed to investigate the sources of the Missouri, to learn how the continental divide could be crossed, and to ascertain the nature of the streams which flowed westward to the Pacific. They were also to study the resources of the country, and to examine into the character and customs of all the Indian tribes that they should meet. The start was made from St. Louis in May, 1804, with two large rowboats and one sail-boat. The latter was to return with news of the party when the farthest outpost upon the Missouri was reached. Through the summer months and late into the fall the boats toiled up the river against the swift current, finally reaching a village of the Mandan Indians in the present state of North Dakota, where the explorers spent the winter. Thus far they were in a region frequently visited by the traders and trappers from St. Louis. [Illustration: FIG. 67.--THE GREAT FALLS OF THE MISSOURI] In the spring they pushed on again in canoes, at length entering an unknown region. The Missouri forked so frequently that it was often difficult to determine which was the main stream. To the surprise of the travellers, the country appeared to be uninhabited, so that they could get no assistance from the Indians. Only a small stock of provisions remained, and as the party numbered about thirty, it was necessary to keep hunters out in advance all the time. As we are carried swiftly through this region to-day in the cars, no signs of wild creatures are to be seen, and it is difficult for us to believe that game was once abundant. The narrative of the expedition abounds with descriptions of various large animals which the explorers met in herds, such as deer, antelope, buffalo, bears, and wolves. The bears, both white and brown, were very numerous and bold. The white bears in particular were so ferocious that the hunters had many serious encounters with them. They would sometimes enter the camp at night, and at one time a herd of buffalo stampeded through it. When undecided at one point which branch of the river to follow, Captain Lewis went some distance in advance and discovered the Great Falls of the Missouri. He was greatly impressed and awed by the magnitude and height of the successive falls, which were twenty-four, forty-seven, and eighty feet high respectively, and were connected by a series of cascades. Many days were spent there in a long and laborious portage, for everything had to be carried a distance of twelve miles before the quiet water above the falls was reached.