The first explorers constructed a rude raft for the purpose of visiting these islands and exploring the shore-line of the lake, but it was speedily wrecked by the choppy waves beat up by the sudden gusts from the mountains. The Geological Expedition took the precaution to carry from Fort Ellis the framework of a little craft, twelve feet long, three and a half feet wide, and twenty-two inches deep, which, covered with well-tarred canvas, made a very serviceable boat for fair-weather navigation. "Our little bark, whose keel was the first to plow the waters of the most beautiful lake on the continent," says Dr. Hayden, "was named by Mr. Stephenson in compliment to Miss Anna L. Dawes, the amiable daughter of Hon. H. L. Dawes. My whole party," he adds, "were glad to manifest, by this slight tribute, their gratitude to the distinguished statesman, whose generous sympathy and aid had contributed so much toward securing the appropriation which enabled them to explore this marvellous region." [Illustration: THE FIRST BOAT ON YELLOWSTONE LAKE.] The little craft rode the waves well and performed excellent service. Its first voyage was to Stephenson's Island, named after the first assistant of the expedition. CHAPTER XI. AROUND YELLOWSTONE LAKE. The Yellowstone leaves the Lake with an easy flow in a channel a quarter of a mile wide, and deep enough to swim a horse. A mile to the eastward of the outlet is the mouth of Pelican Creek, whose swampy valley is the resort of myriads of waterfowl. On the northern side, three or four miles from the lake, Sulphur Hills stand as monuments of a once magnificent system of boiling springs.