Page:The Atlantic Monthly, Volume 17.djvu/346

338 Red hermatite, iron ore, traces of copper, and plumbago are found along the main Bitter Root. Cinnabar is said to exist along the Hell Gate. Coal is found along the Upper Missouri, and a deposit of cannel coal near the Three Butts, northwest of Fort Benton, is also said to exist. Iron ore has been found on Thompson's farms on the Clark's Fork. Sulphur is found on the Loo Loo Fork, and on the tributaries of the Yellow Stone, and coal oil is said to exist on the Big Horn These great mineral deposits must have an ultimate bearing upon the location of the Pacific Railroad, adding, as they will, trade, travel, and wealth to its every mile when built

"The great depots for building material exist principally in the mountain sections, but the plains on either side are not destitute in that particular. All through the Bitter Root and Rocky Mountains, the finest white and red cedar, white pine, and red fir that I ever have seen are found."

The geological formation of the heart of the continent promises to open a rich field for scientific exploration and investigation. The Wind River Mountain, which divides the Yellow Stone from the Great Basin, is a marked and distinct geological boundary. From the northern slope flow the tributaries of the Yellow Stone, fed by springs of boiling water, which perceptibly affect the temperature of the region, clothing the valleys with verdure, and making them the winter home of the buffalo,—the favorite hunting-grounds of the Indians,—while the streams which flow from the southern slope of the mountains are alkaline, and, instead of luxuriant vegetation, there are vast regions covered with wild sage and cactus. They run into the Great Salt Lake, and have no outlet to the ocean. A late writer, describing the geological features of that section, says:—

"Upon the great interior desert streams and fuel are almost unknown. Wells must be very deep, and no simple and cheap machinery adequate to drawing up the water is yet invented. Cultivation, to a great extent, must be carried on by irrigation."

Such are the slopes of the mountains which form the rim of the Great Basin, while the valley of the Yellow Stone is literally the land which buds and blossoms like the rose. The Rosebud River is so named because the valley through which it meanders is a garden of roses.

And here, along the head-waters of the Yellow Stone and its tributaries, at the northern deflection of the Wind River chain of mountains, flows a river of hot wind, which is not only one of the most remarkable features of the climatology of the continent, but which is destined to have a great bearing upon the civilization of this portion of the continent. St. Joseph in Missouri, in latitude 40°, has the same mean temperature as that at the base of the Rocky Mountains in latitude 47°! The high temperature of the hot boiling springs warms the air which flows northwest along the base of the mountains, sweeping through the Big Hole Pass, the Deer Lodge, Little Blackfoot, and Mullan Pass, giving a delightful winter climate to the valley of the St. Mary's, or Bitter Root. It flows like the Gulf Stream of the Atlantic. Says Captain Mullan: "On its either side, north and south, are walls of cold air, and which are so clearly perceptible that you always detect the river when you are on its shores."

This great river of heat always flowing is sufficient to account for the slight depth of snow in the passes at the head-waters of the Missouri, which have an altitude of six thousand feet. The South Pass has an altitude of seven thousand eight hundred and eighty-nine feet. The passes of the Wasatch Range, on the route to California, are higher by three thousand feet than those at the