(Not official.) - Ch2o=29.93. Synonyms. - Formal. Formic Aldehyde. A gas soluble in water. The solution known as Formalin contains about 40 per cent. of the gas.


It is obtained by the oxidation of methylic alcohol at a moderately high temperature or by passing the vapor over red-hot metal.


The solution of Formaldehyde is colorless, having a peculiar odor and an irritative taste. Solubility. - Readily in water and in Alcohol.

Action and Therapeutics of Formaldehyde

Formaldehyde is a powerful disinfectant. It hardens the skin and is irritant to the respiratory raucous membranes. It is used diluted with twenty-five times its bulk of water as a preservative for anatomical specimens, which do not shrink in it, and, in 1 to 60 aqueous solution, as a hardening agent in histological work. As a germicide it is about equal to corrosive mercuric chloride, but is not much used in surgery as it retards healing. As a powerful disinfectant it can be employed for large rooms, when volatilized in a special lamp. It does not bleach colored fabrics. The penetrating power of the gas depends largely upon the conditions of moisture, although under favorable circumstances it may be considerable. If the micro-organisms are exposed they will be destroyed within a half hour by a quart; 960 c.c., volatilized in a room fifteen feet square, and ten feet in height; if protected, within an hour and a half. Small animals accidentally confined in rooms undergoing this process rarely survive, when it is properly carried out (Harrington).