Then the fleeing hunter ran at his topmost speed toward the river, about a mile distant. Arriving there a little ahead of his pursuers, he plunged into the water and swam as fast as he could. Observing a raft of drift-wood that had lodged against a small island, he dived under the debris, and thrusting his head up between the tree-trunks of the heterogeneous mass succeeded in getting into a position where he could breathe and yet be concealed. No sooner had he hidden himself than the yelling savages appeared on the river's bank. They looked in all directions for their missing captive, but in vain. They even went on the island and climbed over the drift-wood, scanning every possible place of concealment. Seeing no trace of their white prisoner they reluctantly returned to the mainland. Coulter remained under the raft in dreadful suspense until night, when, hearing nothing of his foes, he silently slipped from under the raft and swam down stream a long distance before landing. His situation was now indeed a desperate one; his feet had become filled with thorns from the prickly pear while running across the prairie; he was also naked, hungry, and without means to kill the wild game for food; moreover, the distance to the nearest fort was at least a seven-days' journey. But he was in excellent physical condition and, being inured to hardships and skilled in traversing the pathless wilderness, he at length reached the fort, having subsisted in the meantime chiefly on roots whose nutritious value he had learned from the Indians. John Bridger, a famous hunter, was familiar with the region now known as Yellowstone Park as early as 1830, and he endeavored to have his descriptions of it published, but he could find no periodical or newspaper willing to print his statements. In Bridger's case, however, there was ground for doubt, inasmuch as he had a reputation for exaggeration, and the facts that he related about the wonders of the Yellowstone were considered mere fabrications. One of his most astounding stories concerned an elk. He claimed that while hunting he espied an elk that seemed to be only a short distance away; taking a good aim he fired, but the animal was unmoved by the shot. He again fired with more deliberation, yet with the same result as before. Having fired twice more with no effect he seized his rifle by the barrel and rushed toward the antlered monarch; but all at once he ran up against what seemed to be a high vertical wall. On investigation the wall proved to be a mountain of perfectly transparent glass. And still the elk kept on grazing quietly! The strangest thing about the mountain he said was that its curved form made it a perfect telescopic lens of great power. On going around to the other side of the mountain he caught sight of the elk, which he judged must have been at least twenty-five miles away when he first saw it by the powerful glass-lens mountain!