Guidebook of the Western United States: Part A. The Northern Pacific Route with a Side Trip to Yellowstone Park

Campbell, M; Et Al.

If his journey to the Pacific coast begins at one of the great cities on the Atlantic seaboard, the traveler, when he reaches St. Paul, the eastern terminus of the Northern Pacific Railway, will have gone nearly halfway across North America. He will have traversed or perhaps gone around the Appalachian Mountain region and then crossed the prairie States, which, in wealth and population, form in themselves an empire. St. Paul is in the prairie region, but the boundary between the prairies and the Great Plains is vague and undefined, and the traveler will at no place perceive the change from prairie to plain or from the East to the West. On leaving St. Paul he first passes across rolling prairies, interspersed with forests of pine and hardwood trees, and within a short distance these prairies give place to the vast treeless plains which, stretching a thousand miles west of the Mississippi, rise almost imperceptibly to the foothills of the Rocky Mountains. The annual rainfall diminishes in the same direction from 28 inches at St. Paul to only half that amount in central Montana, and the traveler, as he goes Westward, will note more and more of the features that he has habitually associated with the West. Prairie dogs and jack rabbits are seen; one by one the flowers and shrubs of the Mississippi Valley disappear and are replaced by those of a semiarid country; trees grow only on the moist bottom lands along the streams; intensive cultivation is possible only in the valleys, though the uplands are being brought into use by dry farming and are yielding fair crops of the more hardy grains. Throughout much of the region traversed the face of the country has been greatly modified by the vast ice sheets of the glacial period which covered the northern part of the continent and left immense deposits of loose material on the surface of hard rock in the northern part of the United States. The history and the phenomena of this glaciation are considered in detail at several places in this book. The general features of the country west of the Mississippi are represented on Plate I. When, after crossing the Great Plains, the traveler reaches the foothills of the Rocky Mountains he will have attained a height of 4,000 feet above the sea, a height reached by few peaks in the Eastern States outside of the Adirondacks and the White Mountains. The Rocky Mountains form a great, irregular, rough-hewn "backbone" for the continent. They comprise many groups of ranges, in which some peaks in Montana and Idaho reach a height of 12,000 feet above sea level and some in Colorado rise more than 14,000 feet.