less than nine miles.

The basin filled by the Spring might be called a lake, as its size of
two hundred by three hundred feet gives it that appearance, and the
color is a remarkable deep blue. The volume of water is so nearly
uniform that the height seldom varies more than two or three inches,
but three years ago a storm of unusual violence carried out most of the
native fish, and in restocking from Government supplies, the clear, cold
water suggested an experiment with mountain trout which are found to be
doing well.

Where Mammoth Spring flows out its power is utilized by a flour mill on
one bank and a cotton mill on the other, and the water flowing on forms
Spring River, well known for the charm of its beautiful scenery.

This Spring is described by Dr. David Dale Owen in his First Report of a
Geological Reconnoissance of the northern counties of Arkansas, 1857 and
1858, pp. 60-61.




CHAPTER VIII.

THE BLACK HILLS AND BAD LANDS.


In order to thoroughly appreciate and enjoy the wonderful caves of South
Dakota, which are found within the limits of the Black Hills, it is
necessary to have some knowledge of the geological character and history