Page:Popular Science Monthly Volume 12.djvu/721

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times fester for months. Stoats are tough as leather; though severely nipped by the iron fangs of the gin, struck on the head with the butt of the gun, and seemingly quite lifeless, yet, if thrown on the grass and left, you will often find on returning to the place in a few hours time that the animal is gone. Warned by experiences of this kind, the keeper never picks up a stoat till "settled" with a stick or shot, and never leaves him till he is nailed to the shed. Stoats sometimes emit a disgusting odor when caught in a trap. The keeper has no mercy for such vermin, though he thinks some other of his enemies are even more destructive.—Pall Mall Budget.



SCARCELY had the grand truth been well demonstrated, some thirty years ago, that force can neither be created nor annihilated, when it served as a basis for one of the boldest theories ever conceived in the history of science. Prof. William Thomson (now Prof. Sir William Thomson) in 1853 first broached the theory of the dissipation of energy, and since that time many other eminent men have enlarged it and speculated upon it.

The theory points out, in the first place, that different phases of energy are not transformable into one another with equal ease and completeness. Heat is the only form into which any other can be totally converted. When electricity, mechanical motion, or any kind of energy but heat is sought, an undesired production of thermal effect is unavoidable in the most favorable conditions for efficient conversion known to science. Therefore, in the catalogue of terrestrial forces heat is continually gaining in amount at the expense of every other mode of motion.

Further, not only is it impossible, by any known method, to regain from heat more than one-fourth its theoretical value in useful work, but, as the tendency of all heat is ever to become of uniform temperature, by radiation and conduction, the differences of degree wherein its value as a source of other motion solely lies are being continually abolished. The tendency of energy to appear more and more as uniformly diffused heat is further shown to be true not only on earth but in the heavens. With respect to the solar system, our present information, it is held, indicates that it is gradually drifting toward an utterly lifeless state. The sun is parting with its stores of force most lavishly, and must, at however distant a period, become as cold as its planets are now. The planets are little by little losing their force of axial rotation from the friction of their tides, which transmute it into heat;