Page:The Journal of geology (IA journalofgeology11893univ).pdf/236

The south coast of Alaska from Glacier bay on the east to the vicinity of the mouth of Copper river on the west, is bordered by a system of lofty mountains composed of many short ranges, which present steep escarpments to the south and overlook a narrow coastal-plain. At times the plain is wanting as in the vicinity of Mt. Fairweather, and the mountains rise directly from the ocean to great heights. To the north of the uplifts, facing the sea, there is an excessively rugged plateau probably about a hundred miles broad, and with a general elevation of eight or nine thousand feet. On this plateau there are hundreds of short ranges and isolated peaks rising by estimate some five or six thousand feet above the ice-filled valleys, while some of the more prominent summits have a still greater elevation. The northern border of this rugged region has been only partially explored but is known to be less precipitous than its southern face. The elevated region is destitute of both plant and animal life, and is covered with a vast névé field through which many precipitous peaks project. The southern slopes of these islands in the desert of snow are frequently bare in summer and furnish the only relief to the mantle of perpetual white. It is in this region that the ice streams supplying the Malaspina glacier have their sources.

The Tyndall glacier, shown on the accompanying map, is fed by the snow falling on the southwest portion of the Mt. St. Elias range, and flows southward with such a strong current that even after expanding on the plain at the base of the mountains and forming the western lobe of the Malaspina glacier, it continues its southward course and entering the sea forms Icy cape from which thousands of bergs are annually set adrift. Tyndall glacier has important tributaries, especially from the northern side of Robinson hills, but whether it is joined by a glacier from the elevated region to the north of the first range facing the coast, is not known. No break through which a glacier could flow has been observed in the mountain crest to be seen from the ocean, but future explorers may hope to discover such a pass.