The greatest care is necessary to keep spirituous liquors away from the aborigines, a craving for which is beyond their control where there is a possibility of its being obtained. When they fall under its influence they seem to utterly lose their senses, and become dangerous both to themselves and to the whites. As has been intimated, the only means of locomotion is afforded by the watercourses, and the natives, being excellent canoeists, find ample employment of this nature, both in traversing the rivers and along the shore of the islands. The waters of the Yukon, like those of the Neva at St. Petersburg, freeze to a depth of five or six feet in winter. ------------------------------------------------------------------------ CHAPTER XIII. Sailing Northward.—Chinese Labor.—Unexplored Islands.—The Alexander Archipelago.—Rich Virgin Soil.—Fish Canning.—Myriads of Salmon.—Native Villages.—Reckless Habits.—Awkward Fashions and their Origin.— Tattooing Young Girls.—Peculiar Effect of Inland Passages.—Mountain Echoes.—Moonlight and Midnight on the Sea. Let us observe more order in these notes, and resume the course of our experiences in consecutive form. As we speed on our sinuous course northward, inhaling with delight the pure and balmy atmosphere, bearing always a little westerly, winding through narrow channels which divide the richly wooded wilderness of islands, avoiding here and there the ambuscaded reefs, the pleasurable sensation is intense. The scenery, while in some respects similar to that of the St. Lawrence River and the Hudson of New York, is yet infinitely superior to either. After having reached latitude 54° 40′ we come upon Dixon Entrance, a reach of the sea which separates Alaska from British Columbia, and from this point we are sailing exclusively in the purple shadow of our own shore, and in the waters of the United States. At times we pass islands as large as the State of Massachusetts, whose picturesque and irregular mountainous surfaces are covered with immemorial trees, and whose unknown interiors are believed to be rich in coal, iron, silver, and other metals. The axe has never echoed in the deep shade of these dense plantations of nature; they form a pathless wilderness, solemn and silent, save for the stealthy tread of wild beasts, the mournful music of waving pines, and the occasional notes of wandering seabirds. The migratory flocks of the tropics as a rule go farther north to raise their broods, but a few, weary of wing, shorten their aerial journey and build nests on these islands. For many centuries past the great columnar trees have grown to mammoth size, and have then fallen only by the weight of years, enriching the ground with their decayed substance and giving place to another similar growth, which, in its turn, has also flourished and passed away. How like the course of human races! This process has been going on perhaps for twice ten thousand years.