Page:Popular Science Monthly Volume 14.djvu/109

Rh mountains, ruggedly advances, carrying limestone bowlders, and terminating three miles from the head of the pass in a steep precipice one hundred feet high, where its final burdens are discharged down the mountain. Snow-beds or small glaciers are of constant occurrence at the heads of the ravines, and the cool water-brooks which traverse the slopes spring from their melting edges. In Butna Valley the traveler passes for two miles among huge bowlders, then crosses a moraine, and finally reaches a plain encircled by lofty mountains, some of which reveal resplendent pyramids of snow which "bind" into a glacier, filling the head of the valley. Its Surface is obscured by masses of rock and gravel, and beyond its present limits similar proofs of its ravages lie in bewildering confusion. From the valley of Nubbra the traveler beholds the encircling peaks brilliant and luminous in the blaze of countless snow-fields, while icy currents, confluent in larger glaciers, stream from the distant heights. One of these, approached through avenues of bowlders, is half a mile wide, and black with a coverlid of stones and dirt. Neighboring ravines conceal kindred masses whose extremities retire from terminal heaps of bowlders, landmarks of their former expansion. The magnificent glaciers north of Sassar are conspicuous and famous. The large glacier passes down the mountain-side, ploughing a deep furrow through an alluvial plain and plunging into the Shayuk River, whose waters eddy and boil from underneath it. Two moraines accompany it, one of enormous blocks and sixty feet high, outside of its present shrunken area, formed in the glacier's former strength, and a smaller one upon it. In furrows, fifteen and twenty feet deep, upon its surface are sunk strings of rocks imbedded in the icy matrix, and released in occasional showers from its terminal cliffs upon a talus of fragments thus accumulated. In the Shigri Valley and at Zanskar, enormous glaciers are gathered together in companies. Some are literally buried beneath the extraordinary heaps of rocks and detached slabs which are caught upon them from shattered cliff and stony avalanche. They work their way underground, while grass and flowers decorate the desolate covering which conceals them. The valleys of Thibet show unmistakably the past presence of extensive glaciers. Moraines and traveled blocks reach low down into them, often three thousand feet lower than the existing termini of the glaciers.

If, leaving the inhospitable terraces of Thibet and the sublime and unrivaled summits of the Himalayas, we traverse the ice-covered tableland of Greenland, we shall encounter the same phenomena as those we have examined in the Alps, in Norway, and in India, but so magnified in extent as to become continental, and in a measure reconstruct the picture of a world hidden beneath a universal mer de glace. Greenland stretches down from those vast and unexplored regions, whose limits encircle the pole, in a broad wedge-like peninsula, deeply fissured by fiords and bays, its margins abruptly rising in mural precipices, and bearing upon its bosom the oppression of an illimitable glacier. From