16. An Untouched Source of Energy.
The applications of steam and electricity have so far astonished and gratified the rebel Man, that he is sometimes disposed to conclude that he has come to the end of his power of relieving himself from the use of his own muscles for anything but refined movements and well-considered health-giving exercises. One of the greatest of chemical discoverers at this time living, M. Berthelot, has, however, recently pressed on our attention the question of the possibility of tapping the central heat of the earth and making use of it as a perennial source of energy. Many competent physicists have expressed the opinion that the mechanical difficulties of such a boring, as would be necessary, are insuperable. No one, however, would venture to prophesy, in such a matter as this, that what is prevented by insuperable obstacles to-day may not be within our powers in the course of a few years.