The process for this preparation has not retained its place in the London Pharmacopœia, as it is now universally superseded by the Acetic acid distilled from wood. Since however it possesses peculiar chemical habitudes, it claims some notice in this work. The concentrated acid obtained from the decomposition of acetic salts, by the action of sulphuric acid, is pungent, acrid, and volatile, and when heated with free access of air, it takes fire very readily. Its solvent powers are much greater than those of distilled vinegar; it is capable of dissolving camphor, resins, and essential oils[340] copiously, but they are precipitated by dilution; it combines with alcohol, and forms a species of ether; with water it unites in any proportion, heat being evolved by the mixture. Gold, platinum, glass, and earthenware, can alone retain this acid without being corroded. It blisters the skin immediately. I shall conclude this article by the introduction of a Table, which I have constructed with considerable care, for the use of the practical Chemist. The accuracy of the results may be depended upon, since it has been tested by several different modes of enquiry. The Medicinal Dynameter will give the equivalents in any other denomination that may be required. A TABLE EXHIBITING THE ACETOMETER STRENGTHS, SPECIFIC GRAVITIES, PERCENTAGE OF REAL ACID, EQUIVALENT VALUE, AND SATURATING POWER, OF THE MORE IMPORTANT PREPARATIONS OF ACETIC ACID. ┌────────────────┬──────────┬────────┬──────────┬───────────┬─────────┐ │ ACIDS. │ │ │ │ │Grains of│ │ │ │ │ │ │ Sub- │ │ │ │ │ │ │carbonate│ │ │ │ │ │ │ of Soda │ │ │ │ │ │ │saturated│ │ │ │ │Percentage│ │ by 100 │ │ │Acetometer│Specific│ of real │Equivalents│grains of│ │ │strength. │Gravity.│ Acid. │in Minims. │ acid. │ ├────────────────┼──────────┼────────┼──────────┼───────────┼─────────┤ │Acetum │ │ │ │ │ │ │ Destillatum │ 5·9°│ 1·005│ 2·80│ 810│ 8·58│ ├────────────────┼──────────┼────────┼──────────┼───────────┼─────────┤ │ D° │ 6°│ 1·006│ 2·826│ 803│ 8·66│ ├────────────────┼──────────┼────────┼──────────┼───────────┼─────────┤ │ D° │ 7°│ 1·007│ 3·42│ 663│ 10·48│ ├────────────────┼──────────┼────────┼──────────┼───────────┼─────────┤ │ D° │ 10°│ 1·009│ 4·73│ 480│ 14·5│ ├────────────────┼──────────┼────────┼──────────┼───────────┼─────────┤ │Acetum (Proof) │ 10°│ 1·014│ 4·73│ 480│ 14·5│