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Rh out with a view to the economical use of coal, but the two to which we have alluded give up to the present time the best results. Still, with these we allow more than one-half of the heat latent in the coal to escape us. The subtle element eludes our grasp—our charms are powerless to chain the sprite; he will not be bound to labor for us, but passes off into space, regardless of the human Prospero whose wand of science he derides.

In conclusion, our philosophy has enabled us to determine the heat-value of our coal-fields, and to prove that all this heat has a solar origin. Our science has shown us that, although we can eliminate all this heat, we cannot use it. There is an immense quantity constantly passing into space as radiant heat which we cannot retain.

The circle of action between the vegetable and the animal world is a beautiful and a remarkable provision. The animal burns carbon, and sends into the air carbonic acid (a compound of carbon and oxygen); the vegetable breathes that carbonic acid and decomposes it; the carbon is retained and the oxygen liberated in purity, to maintain the life and fire-supporting principle of the atmosphere. Changes similar to these may be constantly going forward in the sun, and producing those radiations which are poured forth in volumes, far beyond the requirements of all the planets of our system. Although there is probably some circle of action analogous to that which exists upon this earth, maintaining the permanency of the vegetable and animal world, still there must be a waste of energy, which must be resupplied to the sun.

May it not be that Sir Isaac Newton's—idea that the comets traversing space gather up the waste heat of the solar system, and eventually, falling into the sun, restore its power—is nearer the truth than the more modern hypothesis, that meteorites are incessantly raining an iron shower upon the solar surface, and by their mechanical impact reproducing the energy as constantly as it is expended?—Popular Science Review.



ILLIAM BENJAMIN CARPENTER was born in Exeter, October 29, 1813. His father, Dr. Lant Carpenter, was a dissenting minister, favorably known as a writer on theological subjects. More widely known, however, as a zealous worker in the cause of juvenile reformation, is his sister, Miss Mary Carpenter. Only his earliest childhood was spent in Exeter, for in 1817 the family removed to 