HARVARD COLLEGE LIBRARY FROM THE LIBRARY OF WILLIAM ROBINSON LAMAR SEPT. 22, 1930 CHEMICAL LABORATORY THE AMERICAN JOURNAL OF PHARMACY JANUARY, 1900. ON ACETIC ACID AS A SUBSTITUTE FOR ETHYL ALCOHOL IN EXTRACTING THE ACTIVE PRINCIPLES OF SOME OFFICINAL DRUGS. BY EDWARD R. SQUIBB, M.D., Of Brooklyn, N. Y. (Third Paper, Belladonna Root.) In continuing this subject for a third paper-see AMERICAN JOURNAL OF PHARMACY for January, 1899, Vol. 71, No. 1, and Vol. 71, No. 7, for July, 1899, and Ephemeris, Vol. V, No. 3, for July, 1899, for the two preceding papers-the writer refers to without repeating the introductory matter of the first paper where the therapeutic and pharmaceutic bearings of the subject are discussed, and passes on to the farther work which is to be depended upon to support or oppose the proposed substitution, or ascertain the limits of its applicability. The experimental trials and the actual use chiefly in veterinary practice of extracts and fluid extracts made with acetic acid have continued since the date of the last paper, until now the list embraces some sixty drugs and spices. This increasing experience tends to support two generalizations. First, that a menstruum of 10 per cent. acetic acid is about the weakest that will surely extract, protect and preserve the active principles of many drugs, and that such a menstruum leaves not less than 6 nor more than 8 per cent. of free acid in the finished fluid extract, and is about equivalent as a menstruum to the officinal alcohol dilutum, or 41 per cent. alcohol. Second, that from one-fourth to one-third of the fluid extracts |