FORMIC ACID, a monobasic organic acid having the formula or H.COOH, the final H in the last of these formula being the one that is replaced when the acid combines with bases to form its salts (which are known as “formatesp). It is an important substance in organic chemistry, and may be obtained by the oxidation of methyl alcohol, as well as of starch, sugar and other organic substances. The most convenient method of preparing the acid is by heating anhydrous glycerin with crystallized ox alic acid. The reaction is not a simple one, monoformin being one of the intermediate prod ucts; but the obvious part of the reaction is that the oxalic acid is converted into formic acid with liberation of carbon dioxide. Pure anhy drous formic acid is a pungent, colorless liquid, boiling at about 212° F. at ordinary atmospheric pressure (its vapor burning with a bluish flame), and freezing at about 47° F. into a white
crystalline mass. Formic acid is completely resolved by strong sulphuric acid into water and carbon monoxide, H.COOH H20 + CO. It reduces Fehling's solution (q.v.), and also re duces gold and platinum to the metallic state, from their solutions. When boiled with the nitrates of rilver and mercury, formic acid pre cipitates these metals in the form of grayish metallic powders. Formic acid is a strong re ducing agent and a powerful antiseptic; both the acid and its salts are used as disinfectants and preservatives. It is also used in dyeing. The acid takes its name from the fact that it exists, in the free state, in the bodies of red ants (Formica rata), from which it may be obtained by crushing the ants and distilling the mass with water.