A structure similar in nature to the Devil's Postpile, but vastly greater in size and sensational quality, forms one of the most striking natural spectacles east of the Rocky Mountains. The Devil's Tower is unique. It rises with extreme abruptness from the rough Wyoming levels just west of the Black Hills. It is on the banks of the Belle Fourche River, which later, encircling the Black Hills around the north, finds its way into the Big Cheyenne and the Missouri.
This extraordinary tower emerges from a rounded forested hill of sedimentary rock which rises six hundred feet above the plain; from the top of that the tower rises six hundred feet still higher. It is visible for a hundred miles or more in every direction. Before the coming of the white man it was the landmark of the Indians. Later it served a useful purpose in guiding the early explorers.
To-day it is the point which draws the eye for many miles. The visitor approaching by automobile sees it hours away, and its growth upon the horizon as he approaches is not his least memorable experience. It has the effect at a distance of an enormous up-pointing finger which has been amputated just below the middle joint. When near enough to enable one to distinguish the upright flutings formed by its closely joined pentagonal basaltic prisms, the illusion vanishes. These, bending inward from a flaring base, straighten and become nearly perpendicular as they rise. Now, one may fancy it the stump of a tree more than a hundred feet in diameter whose top imagination sees piercing the low clouds. But close by, all similes become futile; then the Devil's Tower can be likened to nothing but itself.
This column is the core of a volcanic formation which doubtless once had a considerably larger circumference. At its base lies an immense talus of broken columns which the loosening frosts and the winter gales are constantly increasing; the process has been going on for untold thousands of years, during which the softer rock of the surrounding plains has been eroded to its present level.
One may climb the hill and the talus. The column itself cannot be climbed except by means of special apparatus. Its top is nearly flat and elliptical, with a diameter varying from sixty to a hundred feet.
From a photograph by Tibbitts
