Page:Popular Science Monthly Volume 50.djvu/42

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POPULAR SCIENCE MONTHLY.

glass. The crater was extinct, no signs of steam or of recent eruptions meeting the eye. We were told that on the summit of the cone there is a hot-steam vent, the last dying embers of past volcanic action. Mr. Sissons, while guiding a traveler to the summit, was once belated and had to spend the night there, and saved the lives of himself and his companion by lying close to the steam vent, the steam passing up through the snow. On their descent they slid down over the snow fields of the summit to the lava beds below.

The outlet of the crater, or point of overflow at the last eruption, was on the western side, where small masses of black obsidian and white incrustations of lime were observed.

Turning away from this wonderful view, we walked over the snow and down the loose rocky sides to a rock overlooking the Whitney Glacier. This ice stream, which stretched uphill past the crater to its source, is about three miles long, and on the north side of the mountain, at a point about 13,500 feet high, it heads in a snow field, or mer-de-glace, which is continuous with the head of the McCloud Glacier. Toward the top a large mass of lava projects above the surface of the ice, which is white and very clear near the top; but below this point the glacier is much discolored, more so than any Alpine glacier I have seen. Owing to the steep and uneven pitch of the rocky bed, the surface of the ice, especially near the upper end of the glacier "cascades," or breaks into needles, being rent by numerous crevasses. On each side is a well-marked lateral moraine, with its steepest side next to the overhanging wall of lava; the moraine on the western side begins much lower down. The one on the east side ends in three ridges of dirt and rock, the two uniting to form the great terminal moraine, and, looking far down the glacial stream, this moraine was seen to pass under the ice, or rather the ice overrode it, since the glacier was seen here and there to project above it. Large bowlders or blocks of lava were scattered over it, and its surface was very uneven, with irregular mounds of débris and deep pit-holelike hollows or basins between them. The terminal moraine was overlooked by a small volcano or monticule perhaps a thousand feet high, with nine or ten crater cones rising from its sides—a beautiful example, and reminding me, as I remember them, of the monticules on the flanks of Mount Etna.

At and beyond the end of the present terminal moraine stretches away in the distance a number of old moraines, naked and bare as when they were born, forming plains and overlooked by well-wooded hills. A rapid stream with a white bed runs from the end of the glacier in a northerly direction into Shasta Valley, and at night it is not frozen.

On the northeastern side near the end of the glacier are three