Your National Parks, with Detailed Information for Tourists

by Enos A. Mills; Laurence Frederick Schmeckebier

This is a region worthy of multitudes of visitors, yet it has only a few. Most people do not dream of its existence. Some time throngs will come to these strange island shores in the sky as freely as now they crowd to the beach and the breakers of the sea.

3. THE WORK OF THE ICE KING

With his glaciers the Ice King ground most of the soil in which now stand the forests, the grasses, and the flowers. In producing this soil he sculptured from the solid rock of the earth much of the scenery, shaped many of the flowing landscapes, and formed the excavations in which ten thousand lakes now rest in beauty. Long ice periods have had their sway, then vanished. Most of the earth appears to have been ice-covered a number of times. Then, after ages, the ice has returned. These periods appear to have alternated with others whose climatic conditions were similar to those now holding sway. The remaining glaciers, the world over, are growing smaller and smaller.

A glacier is a slow-moving mass of ice. It may be as small as an average steamship; it may be less than a mile wide and several miles long; or it may cover hundreds of square miles. It may be less than a hundred feet, or a thousand feet or more, in thickness. It may move only an inch or two a day, or it may move several feet. Commonly it moves downward, but occasionally one moves upward. The movement is due to gravity and to the plasticity or rubbery nature of the ice when under sufficient pressure or weight. In a large glacier the weight of the superimposed icy stratum is immense; it is greater than the bottom layers can support. Under the enormous pressure the bottom layers crawl or flow from beneath like pressed dough. This forced mass moves outward in the direction of the least resistance—commonly down the slope.

Glacier ice is formed by snow accumulating at a given point more rapidly than it melts. This is due chiefly to wind, snowslides, and heavy snowfall. The glacier, heavy and powerful, planes, polishes, and reshapes the surface over which it travels, or the walls with which it comes in contact. Most of the lake-basins were gouged out by glaciers. Mountain-ranges have been worn down to hills or plains; cañons and depressions have been filled, and extensive areas overlaid with ground-up rocky material. The gentle snowflake has been the earth's chief maker of scenery and soil. Snowflakes, working en masse and through long periods of time, have formed glaciers and as such have wrought wonders.

A moraine is an embankment or delta of boulders and crushed rock deposited by a glacier or ice river. Though commonly at the end, it may be both along the side and at the end of a glacier, or of the channels which the glacier once filled. All the mountainous National Parks have important glacial records or ruins that almost entirely cover them. These are moraines, soil-deposits, glaciated cañons, and lake-basins.

Vast is the quantity of material picked up and transported by glaciers. Mountains are moved piecemeal, and are ground to boulders, pebbles, and rock-flour in the moving. Besides the material the glacier gathers up and excavates, it carries the wreckage thrown down upon it by landslides, and also the eroded matter poured upon it by streams from the heights. Most of the material that falls upon the top of the upper end of the glacier gradually works its way to the bottom. At last, with the other gathered material, it is pressed against the bottom and sides and used as a cutting, rasping, or grinding tool till worn to pebbles or powder.

A part of the rocky material gathered is carried to the end of the glacier, where the melting of the ice unloads and releases it. This accumulation at the end is called the terminal moraine, and corresponds to the delta of a river. For years the bulk of the ice may melt away at about the same place; thus at this point accumulates an enormous amount of débris. An advance of the ice may plow through this and repile it, or the retreat of the ice, or a changed direction of its flow, may pile débris elsewhere. Many of these terminal moraines are an array of broken embankments with small basin-like holes and smooth, level spaces.

Many of the lakes have been filled with sediment, and in them and on them forests now flourish. The glacier lakes were slowly created. Most of them are being slowly filled. Those most favorably situated may still live on for thousands of years, but an avalanche may extinguish one in a single day. Eventually all must be filled and lost. They come into existence as a part of the work of the glacier. For a period they lie beautiful in the sunlight; then they are gone forever.

The extensive glacial records that show the past triumphs of the Ice King sometimes make the mind restless, and it wants to know: "Will the Ice King come again? Will mountains of white and silent snow again pile upon a lifeless world?"