"Tuesday, June 4, 1805.--This morning, Capt. Lewis and Capt. Clarke set out, each with a small party, by land, to explore the two rivers. Capt. Lewis traced the course of the north fork for fifty-nine miles, and found, that, for all that distance, its direction was northward; and, as the latitude we were now in was 47° 24´, it was highly improbable, that, by going farther north, we should find between this and the Saskatchawan any stream which can, as the Indians assure us the Missouri does, possess a navigable current for some distance within the Rocky Mountains. "These considerations, with others drawn from the observations of Capt. Clarke upon the south branch, satisfied the chiefs that the South River was the true Missouri; but the men generally were of a contrary opinion, and much of their belief depended upon Crusatte, an experienced waterman on the Missouri, who gave it as his opinion that the north fork was the main river. In order that nothing might be omitted which could prevent our falling into error, it was agreed that one of us should ascend the southern branch by land until he reached either the falls or the mountains. In the mean time, in order to lighten our burdens as much as possible, we determined to deposit here all the heavy baggage which we could possibly spare, as well as some provisions, salt, powder, and tools. The weather being fair, we dried all our baggage and merchandise, and made our deposit, or cache. Our cache is made in this manner: In the high plain on the side of the river, we choose a dry situation, and, drawing a small circle of about twenty inches diameter, remove the sod as carefully as possible. The hole is then sunk perpendicularly a foot deep, or more if the ground be not firm. It is now worked gradually wider as it deepens, till at length it becomes six or seven feet deep, shaped nearly like a kettle, or the lower part of a large still, with the bottom somewhat sunk at the centre. As the earth is dug, it is carefully laid on a skin or cloth, in which it is carried away, and thrown into the river, so as to leave no trace of it. A floor to the cache is then made of dry sticks, on which is thrown hay, or a hide perfectly dry. The goods, being well aired and dried, are laid on this floor, and prevented from touching the sides by other dried sticks, as the baggage is stowed away. When the hole is nearly full, a skin is laid over the goods; and, on this, earth is thrown, and beaten down, until, with the addition of the sod, the whole is on a level with the ground, and there remains no appearance of an excavation. Careful measurements are taken to secure the ready recovery of the cache on the return; and the deposit is left in perfect confidence of finding every thing safe and sound after the lapse of months, or even years." THE FALLS OF THE MISSOURI.