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the spurs projecting from it. The medial moraine looks black from a distance, but, on traversing it, it was found to be composed mainly of dark-green gabbro and serpentine. The débris is scattered over the surface in a belt several rods wide; but it is not deep, as the ice can almost everywhere be seen between the stones. Where the fragments of rock are most widely separated, there are fine illustrations of the manner in which small, dark stones absorb the heat of the sun and melt the ice beneath more rapidly than the surrounding surface, sinking into the ice so as to form little wells, several inches deep, filled with clear water. Larger stones, which are not warmed through during a day's sunshine, protect the ice beneath while the adjacent surface is melted, and consequently become elevated on pillars or pedestals of ice. The stones thus elevated are frequently large, and form tables which are nearly always inclined southward. In other instances the ice over large areas, especially along the center of the medial moraine, was covered with cones of fine, angular fragments from a few inches to three or four feet in height. These were not really piles of gravel, as they seemed, but consisted of cones of ice, sheeted over with thin layers of small stones. The secret of their formation, long since discovered on the glaciers of Switzerland, is that the gravel is first concentrated in a hole in the ice and, as the general surface melts away, acts like a large stone and protects the ice beneath. It is raised on a pedestal, but the gravel at the borders continually rolls down the sides and a conical form is the result.

Where we crossed the Hayden glacier it is only about a mile broad in a direct line; but to traverse it by the circuitous route rendered necessary by the character of its surface required about three hours of hard tramping, even when unincumbered with packs. From the center of the glacier a magnificent view may be obtained of the snow-covered domes of Mount Cook, from which rugged mountain ridges stretch southward like great arms and enclose the white snow-field from which the glacier flows. At an elevation of 2,500 feet the icy portion disappears beneath the névé on which not a trace of débris is visible. All the higher portions of the mountains are white as snow can make them, except where the pinnacles and precipices are too steep to retain a covering.

On reaching the western side of the glacier we found a bare space on the bordering cliffs, about a hundred feet high, which has been abandoned by the ice so recently that it is not yet grassed over. Above this came the luxuriant and beautiful vegetation covering all the lower mountain slopes.

The mountain spur just west of the glacier, like several of the ridges stretching southward from the higher mountains, ends in a group of hills somewhat separate from the main ridge. The hills are covered with a rank vegetation, and in places support a dense growth of spruce trees. Reaching the grassy summit, we had a fine, far-reaching view of the unexplored region toward the west, and of the vast plateau of ice stretching southward beyond the reach of the vision. West of our station, another great ice-stream, named the Marrin, glacier, in honor of the late A. R. Marvine, flows southward with a breadth exceeding that of any of the icy streams yet crossed. Beyond the Marvine glacier, and forming its western border, there is an exceedingly rugged mountain range trending northeast and southwest. Although this is, topographically, a portion of the mountain mass forming Mount Cook, its prominence and its peculiar geological structure render it important that it should have an independent name. In acknowledgment of the services to science rendered by the first state geologist of Massachusetts, it is designated the Hitchcock range on our maps. Rising above the angular crest line of this mountain mass towers the pyramidal summit of Mount St. Elias, seemingly as distant as when we first beheld it from near Yakutat bay.

About a mile west of the hill on which we stood, and beyond the bed of a lake now drained of its waters by a tunnel leading southward through the ice, rose a steep, rocky island out of the glaciers, its summit overgrown with vegetation and dark with spruce trees. This oasis in a sea of ice, subsequently named Blossom island, we chose as the most favorable site for our next advance-camp.

We then returned to our camp in Floral pass, and a day or two later Kerr and Christie started on a side trip up the Hayden glacier, to be absent five days. During this trip the weather was stormy, and only allowed half an hour for topographical work when a somewhat favorable station was reached. This was of great service, however, in mapping the country, as it gave a station of considerable elevation on the side of Mount Cook. The trip was nearly all above the snow-line, and was relieved by many novel experiences.

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