Familiar letters on chemistry, and its relation to commerce, physiology, and agriculture / by Justus Liebig ; edited by John Gardner.

  • Justus von Liebig
Date:
1843
Catalogue details

Licence: Public Domain Mark

Credit: Familiar letters on chemistry, and its relation to commerce, physiology, and agriculture / by Justus Liebig ; edited by John Gardner. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    In this manner every porous body — rocks, stones, the clods of the fields, &c.—imbibe air, and therefore oxygen ; the smallest solid molecule is thus surrounded by its own atmosphere of con- densed oxygen; and if in their vicinity othez bodies exist which have an affinity for oxygen, a combination is effected. When, for instance, car- bon and hydrogen are thus present, they are converted into nourishment for vegetables—into carbonic acid and water. The development of heat when air is imbibed, and the production of steam when the earth is moistened by rain, are acknowledged to be consequences of this conden- sation by the action of surfaces. But the most remarkable and interesting case of this kind of action is the imbibition of oxygen by metallic platinum. This metal, when massive, is of a lustrous white color, but it may be brought, by separating it from its solutions, into so finely divided a state, that its particles no longer reflect light, and it forms a powder as black as soot. In this condition it absorbs eight hundred times its volume of oxygen gas, and this oxygen must be contained within it in a state of condensation very like that of fluid water. When gases are thus condensed, that is, their particles made to approximate in this extraordinary manner, their properties can be palpably shown.
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