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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1809 Excerpt:...shall try it on this piece of wood) it will combine with one or more of the constituents of that substance, and occasion a decomposition. Emily. It has changed the colour of the wood to black. How is that? Mrs. B. The oxygen deposited by the acid has burnt it; you know that wood in burning becomes black before it is reduced to ashes. Whether it derives the oxygen which burns it from the atmosphere, or from any other source, the chemical effect on the wood is the same. In the case of real combustion, wood becomes black because it is reduced to the state of charcoal by the evaporation of its other constituents. But can you tell me the reason why wood turns black when burnt by the application of an acid? Caroline. First, tell me what are the ingredients of wood? Mrs. B. Hydrogen and carbone are the chief constituents of wood, as of all other vegetable substances. Caroline. Well, then, I suppose that the oxygen of the acid combines with the hydrogen of the wood, to form water; and that the carbone of the wood, remaining alone, appears of its usual black colour. Mrs. B. Very well, indeed, my dear; that is certainly the most plausible explanation. Emily. Would not this be a good method of making charcoal? Mrs. B. It would be an extremely expensive, and I believe, very imperfect method; for the action of the acid on the wood, and the heat produced by it, are far from sufficient to deprive the wood of all its evaporable parts. Caroline. What is the reason that vinegar, lemon, and the acids of fruits, do not produce this effect on wood? Mrs. B. They are vegetable acids whose bases are composed of hydrogen and carbone; the oxygen, therefore, will not be disposed to quit this radical, where it is already united with hydrogen. The strongest of these may, perhaps, yield...