Page:Popular Science Monthly Volume 61.djvu/538

532 This 'cave' was probably the place where Baron Müller, who climbed the mountain in 1856, stopped, and where nearly all the mountaineers who have attempted the, ascent since have passed the night. Müller speaks of the 'granite' walls of the cave and other tourists use the same term. But there is no granite here nor elsewhere in the region. The rock masses forming the mountain are singularly uniform. They are eruptive rocks of prevailing dark grayish or brownish color composed of crystals of augite and plagioclase in a fine ground mass and are called andesite. In places glassy masses of obsidian appear, and in others volcanic tuffs and ashes, but in no place is there granite or gneiss.

The following morning at six o'clock, after a hurried breakfast, one guide and I started for the summit. In a few minutes we were above the timber line. Two hours of walking brought us to the snow line, that day at about fifteen thousand feet.

At the lower levels the snow is finely crystalline, very compact and of the variety known as 'firn' or 'névé.' It affords excellent footing to the properly shod climber. Toward the top of the mountain it is softer, though the individual flakes are never large, and the feet sink in to the shoe tops. The beauty of the snow furnishes one of the great rewards to the tourist. The spike of an alpine stock leaves after each thrust a hole of wondrous green in the glittering white mass. The snow fills the chasms of the mountain, smoothes out its ridges, softens