The Committee finally desires to announce that all communications addressed to any member thereof, or to the Chairman, containing suggestions for improvements in the Pharmacopoeia, will be thankfully received, carefully considered, and utilized as far as possible. CHARLES RICE, Ph.D., New York, N. Y., elected Chairman, 1900, died May 13, 1901. JOSEPH P. REMINGTON, Ph. M., Philadelphia, Pa., Chairman. C. LEWIS DIEHL, Ph.M., Louisville, Ky., First Vice-Chairman. REYNOLD WEBB WILCOX, M.D., New York, N. Y., Second Vice-Chair man. ALFRED R. L. DонмE, Ph.D., Baltimore, Md., Secretary. JOHN J. ABEL, M.D., Baltimore, Md. CHARLES CASPARI, JR., Ph. G., Baltimore, Md. VIRGIL COBLENTZ, Ph.D., New York, N. Y. HENRY H. RUSBY, M. D., New York, N. Y. (elected October 10, 1901). LUCIUS E. SAYRE, Ph. M., Lawrence, Kan. WILBUR L. SCOVILLE, Ph. G., Boston, Mass. EDWARD H. SQUIBB, M.D., Brooklyn, N. Y. ALVISO B. STEVENS, Ph. C., Ann Arbor, Mich. H. C. WOOD, M.D., Philadelphia, Pa., Ex-officio. Committee of Revision of the Pharmacopoeia of the United States of America. (Eighth Decennial Revision.) INTRODUCTORY NOTICES POWDERS Fineness of Powder. The fineness of powder is expressed, in the Pharmacopoeia, either by descriptive words (generally so in the case of brittle or easily pulverizable substances), or in terms expressing the number of meshes to a linear inch of the sieve through which the powder will pass. The corresponding values, in terms of metric measures of length, are added below in parentheses, but it has not been deemed advisable, in this revision, to substitute them in the text of the Pharmacopoeia for those at present in use. The diameter of the wire (gauge number) used in making sieve cloth has an important influence upon the size of the mesh, and it is necessary to specify in each case the thickness of the wire. These different forms of expression correspond to each other as follows: should pass through a sieve A very fine powder the linear inch (30 to the A fine powder A moderately fine powder A moderately coarse powder Cm.) and should be made should pass through a sieve should pass through a sieve A coarse powder should pass through a sieve = No. 20 powder. In certain cases, powders of a different degree of fineness (e.g., No. 30, No. 12) are directed to be taken. POWDERS Fineness of Powder. The fineness of powder is expressed, in the Pharmacopoeia, either by descriptive words (generally so in the case of brittle or easily pulverizable substances), or in terms expressing the number of meshes to a linear inch of the sieve through which the powder will pass. The corresponding values, in terms of metric measures of length, are added below in parentheses, but it has not been deemed advisable, in this revision, to substitute them in the text of the Pharmacopoeia for those at present in use. The diameter of the wire (gauge number) used in making sieve cloth has an important influence upon the size of the mesh, and it is necessary to specify in each case the thickness of the wire. These different forms of expression correspond to each other as follows: should pass through a sieve A very fine powder the linear inch (30 to the A fine powder A moderately fine powder A moderately coarse powder Cm.) and should be made should pass through a sieve should pass through a sieve A coarse powder should pass through a sieve = No. 20 powder. In certain cases, powders of a different degree of fineness (e.g., No. 30, No. 12) are directed to be taken. |