Description of the High Rock Spring. 343 
may, at any time, make the experiment of its deleterious ef- 
fects on animal life. 
he following dimensions of this singular production of 
nature, are taken from actual measurement: Perpendicular 
height, four feet ; circumference at the base, twenty six feet, 
eight inches ; length of a line drawn over the rock from north 
to south, eleven feet, seven inches ; length of the same from 
east to west,ten feet, nine inches ; from the top of the rock 
to the surface of the water, two feet four inches; depih of 
water in the cavity of the rock, seven feet eight inches ; the 
hole is nearly circular, and measures ten inches across, 
is rock, very properly, belongs to that species of lime- 
stone termed calcareous tufa, being evidently the product of 
the water. Itis composed of the carbonate of lime, magne- 
sia, and the oxide of iron, together with a proportion of sand 
and clay. It likewise exhibits, when broken, the impressions 
of leaves and twigs of trees. It is somewhat undulated on 
its surface, and, about the top, compact and indurated, while 
near its base it is of a more spongy and friable character, 
but every where sufficiently compact to render it impervious 
to water. 
t 
flow upon its surface, is not quite so obvious ; the most prob- 
able conjecture is, that the basis of this mass was commenced 
beneath the surface of the earth, that the water, thus confi- 
ned within the limits of its own sediment, continued to rise, 
and as it escaped over the sides of its prison, constantly ad- 
ded to the dimensions of its walls. In this manner it would 
continue to rise, until the column of water in the rock balan- 
ced the power that forced it up,in which case it would be- 
come stationary, and it is but just to infer, that, in process o 
time, the power so propelling the water might be diminish- 
ed in its force, when the water in the spring would of course 
sink in exact proportion to the loss of that power. 
There was an opinion prevailing among the early settlers, 
that the rock had been fractured by the fall of a tree, and to 
this accident they imputed the failure of the water to run over 
its top, believing that it escaped through a fissure, which, al- 
though invisible, they still imagined must exist. This conjec- 
ture however, does not appear to be well founded ; the spring 
