Page:A History of the Pacific Northwest.djvu/55

 "Notes on Virginia." In this book he shows considerable knowledge of those portions of the trans-Allegheny region which had been previously explored. He discusses the plants and animals native to those regions, the lead and coal deposits, and calls especial attention to certain extraordinary deposits near the Ohio River of the bones of huge, extinct animals. Our chief interest, however, is to learn what Jefferson at that time knew about those features of western geography which condition the discovery of an overland route to the Pacific, especially the river systems.

Jefferson justifies a special treatment of far western rivers, although they are not within the boundaries of Virginia, on the ground that they open to the people of Virginia "channels of extensive communication with the Western and Northwestern country." . . . His description of the Missouri is most interesting, "The Missouri [he says] is in fact the principal river, contributing more to the common stream than does the Mississippi, even after its junction with the Illinois. It is remarkably cold, muddy, and rapid. Its overflowings are considerable. They happen in the months of June and July. Their commencement being so much later than those of the Mississippi, would induce a belief that the sources of the Missouri are northward of those of the Mississippi, unless we suppose that the cold increases again with the ascent of the land from the Mississippi westwardly. That the ascent is great, is