This great National Park is a volcanic plateau some 10,000 feet above sea level, and embraces a territory fifty-five by sixty-five miles, or 3,575 square miles. It was first visited by John Colter, an attaché of the Lewis and Clarke exploring expedition in 1806, but it was not until nearly fifty years later that stories told of the region by old trappers and hunters were verified by a visit of members of the Geologic Survey. In 1880 it was made a National Park, since which time it has been under the immediate control of the Secretary of the Interior, who appoints a superintendent with headquarters at the Mammoth Hot Springs, and polices the park with a company of cavalry, whose principal care is the protection of game. So faithfully has this duty been executed that the park now abounds with deer, buffalo, elk, bear, and a few mountain lions, besides a great abundance of small game and water-fowl. Upon alighting from the stage at Mammoth Hot Springs Hotel, the first objects that attract the interest of visitors are the pink terraced springs and Cap of Liberty, which are in the front-yard, so to speak. The springs, fifty in number, cover an area of 170 acres and by a constant deposition of carbonate of lime have built up, terrace upon terrace, a mound fully 200 feet high. ------------------------------------------------------------------------ [Illustration: LITTLE JUPITER TERRACE.—The different terraces of the Yellowstone Park cover an area about two miles square. They have the appearance of a frozen cascade, so beautifully scalloped and adorned with a kind of bead work, that the beholder stands amazed and filled with inexpressible admiration. The water flowing over these terraces is so transparent that it is like glass, and the pools below hold the reflection of the sky while mirroring the white crystalline formations, surpassing all art, and more beautiful than anything which can be conceived. ] ------------------------------------------------------------------------ [Illustration: SLUICE-BOX CAÑON, NEAR GREAT FALLS, MONTANA.] The springs have their source somewhere within an active volcanic belt, and thus heated by internal fires they pour out their waters at a temperature of 112° to 163° Fahrenheit, which, acting upon the soft limestone, dissolves and converts it into what geologists call _travertine_, a semi-crystalline deposit that quickly hardens upon coming in contact with the air. When first observed, the terraces resemble a snow-bank, but by other writers they have been compared to the terminal front of a glacier, and again like a foaming cascade suddenly turned into stone. Streaks and patches of red, yellow and green seen upon the white slopes mark the course of overflowing water, while clouds of steam float lightly upward from the many springs, but only to quickly disappear.