Not only is Mount Mazama with its wonderful lake one of the most unique natural features of North America, but it has its full share of the artistic details of lake and mountain scenery which appeal so forcibly to the finer instincts within us. The outer slopes of the mountain are clothed with the all-embracing coniferous forests which cover the Cascades as with a mantle throughout their entire extent, while the precipitous inner slopes are for the most part bare precipices of angular and extremely rugged rock. The lake itself is of the most marvellous blue, in which the encircling cliffs, the crater-island, and the sky above are reflected. [Illustration: FIG. 22.--Mount Rainier, Washington.] Other peaks along the crest-line of the Cascades to be numbered by the score, although with less romantic histories than Mount Mazama, have instructive answers to give when properly questioned. Among the remarkably picturesque summits rising above the dark coniferous forests of western Oregon are the following, with their respective heights above the sea expressed in feet: Mount Pitt, 9,760; Mount Mazama, 8,228; Mount Union, 7,881; Mount Scott, 7,123; Three Sisters, Mount Jefferson, 10,200; and Mount Hood, 11,225. Of these peaks, the best known, on account of its proximity to the city of Portland, and at the same time one of the most picturesque and beautiful, is Mount Hood, situated about 25 miles south of the Columbia River. The concave slopes so characteristic of volcanic cones are no longer conspicuous on the sides of this once symmetrical mountain, and only remnants of its crater remain. The part it played as a safety-valve for the pent-up energy beneath was long since finished, although heated vapours still escape from an opening near the summit. Similar manifestations of heat have also been observed about several other ancient craters in the Cascades, but these occurrences are not considered as indicating that actual connections still exist with reservoirs or bodies of molten rocks below the surface: they are evidently due to the residual heat of the once molten rock in the conduits of the now extinct or dormant volcanoes. The lava-flows and volcanic mountains typically displayed in the Cascades throughout the breadth of Oregon continue northward and form at least the surface portion of the same range in Washington as far as the Northern Pacific Railroad, or about 100 miles north of the Columbia. The more important volcanic mountains in western Washington are, in their order from south to north; as follows, the height of each being given in feet: Mount Adams, 9,570; Mount St. Helens, 9,750; Mount Rainier, 14,525; Glacier Peak, 10,436; and Mount Baker, 10,877. Only two of these ancient volcanoes, namely, Mount Adams and Glacier Peak, are situated on the crest-line of the Cascade Mountains; the others are to the westward and more or less completely detached from the main range.