Through the press and lecture-platform, the Washburn-Doane expedition spread the knowledge of its discoveries broadcast over the country. The direct result of its work was that the United States Government sent an official expedition to the Park the next year. This was a joint expedition made up from the Engineering Corps of the Army and from the United States Geological Survey of the Territories. The official United States Government expedition of 1871 officially put it on the map, with official scientific notes and photographs. Thus the sixth discovery of this wondrous region, after two generations of unbelief, convinced the people that it existed! During these two generations the unexplored wilderness of the Louisiana Purchase had been formed into seven new States of the Union, containing more than five million people. And "Colter's Hell," when its existence had been finally and officially established, was within two hundred and fifty miles of a transcontinental railroad. 3. THE GEYSERS, LAKES, AND STREAMS Water in numberless pleasing forms is one of the attractive features of the Yellowstone Park. There are snowy waterfalls that leap in glory. There are geysers--transient, towering, fluted--with white columns draped with steam. Both the geysers and the waterfalls bring the rainbow to them; or, the prismatic springs go to the rainbow for their colors. The cascades have all the excitement of ocean breakers. The lakes mirror the clouds, and their placid bosoms reflect the stars that are "in the quiet skies." There are streams that wind and linger, and brooks that go on forever. There are hot springs and cold, large springs and small, each with its own attractive setting. Many burst through the roofs of caves; others gush from grottoes; still others pour forth from mounds and columns. The quiescent springs and prismatic pools have a delicate, exquisite, gemlike beauty unlike anything else in the world of nature or of art. The waters are soft blue. Changing lights tinge the water with iridescence; touch its surface with soft luminosity; give to moulded and sculptured basins a refinement of coloring that transcends belief. Dr. Ferdinand V. Hayden gives this glowing description:-- The wonderful transparency of the water surpasses anything of the kind I have ever seen in any other portion of the world. The sky, with the smallest cloud that flits across it, is reflected in its clear depths, and the ultramarine colors, more vivid than the sea, are greatly heightened by constant, gentle vibrations. One can look down into the clear depths and see with perfect distinctness the minutest ornament on the inner sides of the basin; and the exquisite beauty of the coloring and the variety of forms baffle any attempt to portray them either with pen or pencil.