Page:Walcott A Geologists Paradise.djvu/1

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Vol. XXII, No. 6
WASHINGTON
June, 1911
THE
NATIONAL
GEOGRAPHIC
MAGAZINE
   

A GEOLOGIST'S PARADISE

By Charles D. Walcott
Secretary of the Smithsonian Institution

NATURE has a habit of placing some of her most attractive treasures in places where the average man hesitates to look for them. Twenty-five years ago rumors came of a wonderful find of glaciers, forests, mountain peaks, and lakes along the line of the rugged pass through which the Canadian Pacific Railway was building.

A geological reconnaissance by Sir George M. Dawson, of the Canadian Geological Survey, outlined some of the broader geological features, and a somewhat closer study by Mr. R. G. McConnell in 1886 resulted in a more accurate description of the thousands of feet in thickness of sandstone, shale, and limestone that had been arched and broken before being dissected and laid to view by the agents of erosion which formed the canyons, cliffs, and mountains by removing grain by gain or by chemical solution the material that formerly occupied or surrounded them.

A young American, Walter Wilcox, taking his surveying instruments and camera, spent summer after summer sketching maps and photographing the scenery, and in 1869 he published the first of several beautiful volumes on "Camping in the Canadian Rockies." Later, with the development of the kodak, thousands of pictures were taken by tourists who had little thought of the geological treasures lying all about.

The study of the glaciers was begun early by an American, George Vaux, of Philadelphia, assisted by his sister Mary, and later an expedition sent out by the Smithsonian Institution under the leadership of William H. Sherzer, of the University of Michigan, resulted in the publication in 1907 of a memoir describing and illustrating many of the glaciers.

During the past three years an expedition from the Smithsonian has been making an examination of the four miles or more in thickness of bedded rocks forming the main range of the Rocky Mountains that has been pushed eastward by the great mass of the Selkirk ranges to the west. It is a curious and instructive feature of the geology that the strata of the Rockies, although crowded eastward and thrust out over the later rocks of the plains of Alberta, have not suffered nearly as much dislocation, injury, and alteration as the apparently more massive bedded rocks of the Selkirks. The latter are crumpled, broken, and altered in about the same manner as large blocks of brittle paper would be if subjected to side pressure in a hydraulic press.