Fig. 43—A glacial gorge on the northeastern face of Mt. Shasta, California, below Hotlum Glacier (see Fig. 42), the lower end of which is to be seen in the upper part of the photograph. At the left are two ridges, one the edge of a sheet of flow lava, the other, in part at least, a lateral moraine. In the center, at the bottom of the gorge, between the two white lines which represent glacial streams, is a system of concentric ridges which are probably recessional moraines. At the right is the western slope of the gorge. (This figure is the lower overlapping continuation of Fig. 42.)
Fig. 44—Yosemite Valley, California, a typical ice-shaped gorge, showing at the left the granite face of El Capitan, about 3,000 feet above the bottom of the famous gorge, and, at the right, the pinnacle of Sentinel Rock and the well-known form of Half Dome. At the sky line in the center of the picture is Clouds Rest, and well down in the gorge Washington Column and the Royal Arches can be distinguished.
These photographs have the advantage of appealing to the mind through the sense of vision and will serve the same purpose as plaster models. Thus, in Figure 52, a variety of topographic forms are to be distinguished, including slightly dissected highlands with sharply incised gorges; maturely dissected highlands made up now of canyons and ridges; a mountain valley broadening out toward an intermontane plain; several arroyos; and many minor features.