The Mechanical Theory of Earth-Heat

Abstract

NOTICING the assertion made in NATURE, vol. xx. p. 22, in reference to Prof. Church's article in Silliman's Journal on the Comstock Lode, that “the rock in the lower levels seems to have a pretty uniform temperature of 130° F.,” and remembering what Prof. G. F. Barker, of the University of Pennsylvania, told me, that on a recent visit to those mines he found that there was no uniform temperature, but on the contrary, the most remarkable differences, some of the higher levels being much hotter than some of the lower levels—so that he came to two conclusions:—(1) That the heat was a hot water heat, and (2) that the hot waters were heated mechanically by those continuous movements of the country, so plainly shown both in the mines and at the surface;—it occurs to me to ask the following question:—