Published Monthly. Price $6.00 per Annum. THE JOURNAL OF THE AMERICAN CHEMICAL SOCIETY. SEPTEMBER, 1902. WILLIAM A. NOYES, Editor, EDWARD HART, W. F. HILLE- Studies in Denitrification. By E. B. Voorhees.... On the Composition of the Ferrocyanides of Zinc. By Edmund H. Mil- On Standard Tartar Emetic and Its Structural Formula. By F. E. Hale 828 Photometric Determination of Iron. By J. I. D. Hinds and Myrtis On the Determination of Sulphur in Coal. By Charles W. Stoddart.... 852 On a Method for the Determination of Very Small Vapor-Tensions in Certain Circumstances. By Launcelot W. Andrews.... Contributions to the Study of Starch Iodide. By Launcelot W. Andrews A Thermochemical Constant. By F. W. Clarke A New Glass of Low Solubility. By G. E. Barton NOTES: Rapid Volumetric Method for Determining Phosphoric Acid in Entered at the Post-office, Easton, Pa., as Second-class Matter. Everything intended for insertion in the Journal should be addressed to the Editor, William A. Noyes, Terre Haute, Ind. Orders for back numbers of the Journal should be addressed to the Librarian, E. G. Love, 108 West 55th Street, New York City, Changes of address should be sent to the Secretary, A. C. Hale, 352 A Hancock Street, President: Ira Remsen, Johns Hopkins University, Baltimore, Md. Librarian: E. G. Love, 108 W. 55th St., New York City. Committee on Papers and Publications: William A. Ñoyes, Editor; Edward Hart, W. Hillebrand, J. H. Long, Wm. McMurtrie, Arthur A. Noyes, Edgar F. Smith, H. Stokes, H. P. Talbot, H. W. Wiley. Committee on Membership: Wm. McMurtrie; C. L. Reese; E. G. Love. Finance Committee: J. H. Wainwright; Durand Woodman; C. S. McKenna. Council. Members ex-officio: Ira Remsen, Pres.; Albert C. Hale, Sec.; Albert P. Hallock Councilors from Local Sectio Rhode Island Section: Charles A. Catlin. Cincinna w York Section: Leo Baekeland, A. A. Breneman, C. Doremus, T. J. Parker, G. C. Stone. Washington Section: W. F. Hillebrand, H Stokes. Lehigh Valley Section: P. W. Shimer. Chicago Section: J. H. Long. Nebra Section: H. H. Nicholson. North Carolina Section: B. W. Kilgore. Colum Section: Wm. McPherson. North Eastern Section: W. L. Jennings, A. D. Little H. P. Talbot. Philadelphia Section: H. W. Jayne, John Marshall. Michigan Sectio E. D. Campbell. Kansas City Section: J. Robt. Moechel. California Section: J. ). Stillman. Local Sections. Rhode Island Section: Walter M. Saunders, Pres.; Walter E. Smith, Sec. 158 Doyle Ave., Providence, R. I. Cincinnati Section: R. W. Hochstetter, Pres.; J. F Snell, Sec., University of Cincinnati, Cincinnati, O. New York Section: Thomas Parker, Pres.; Francis D. Dodge, 360 Washington Avenue, Brooklyn, N. Y. Washing ton Section: W. F. Hillebrand, Pres.; L. S. Munson, Sec., Dept. of Agr., Washington D. C. Lehigh Valley Section: Joseph W. Richards, Pres.; R. K. Meade, Sec., Lafayet: College, Easton, Pa. Chicago Section: Edward Gudeman, Pres.; W. A. Converse, Sec 27-34 Rialto Bldg., Chicago. Nebraska Section: H. H. Nicholson, Pres.; R. S. Hiltner Sec., University of Nebraska, Lincoln, Neb. North Carolina Section: C. E. Brewer Pres.; C. B. Williams, Sec., North Carolina Dept. of Agr., Raleigh, N. C. Columbs Section: H. A. Weber, Pres.; W. E. Henderson, Sec., Ohio State University, Columbus O. North Eastern Section: L. P. Kinnicutt, Pres.; Henry Fay, Sec., Massachusetts Inst. Tech., Boston, Mass. Philadelphia Section: Henry Leffmann, Pres.; F. E Dodge, Sec., Works of Barrett Mfg. Co., Frankford, Philadelphia. Michigan Section E. D. Campbell, Pres.; Alfred H. White, Sec., 1003 E. University Ave., Ann Arbor, Mich Kansas City Section: E. H. S. Bailey, Pres.; Armand R. Miller, Sec., M. T. High Scho Kansas City, Mo. California Section: Edmond O'Neill, Pres.; Harry East Miller Sec., 331 Pine St., San Francisco, Cal. PAPERS ACCEPTED FOR PUBLICATION. On the Manganese Ferrocyanides. By A. E. Dickie. Note on the Preparation of Metallic Lithium. By Samuel A. Tucker. Note: An Adulteration of Lavender Oil with Salicylic Acid. By Everhard Weber. A Thermochemical Constant; Preliminary Notice. By F. W. Clarke. The Retention of Arsenic by Iron in the March-Berzelius Method. By C. L. Parsons and Mon A. Stewart. Note: A Novel Constant High Temperature Bath. By Charles Baskerville. On the Constitution of Certain Organic Salts of Nickel and Cobalt as they Exist in Solution By O. F. Tower. On the Quantitative Separation of Maltose and Lactose. By Charles I. Boyden. Observations on the Electrolytic Precipitation of Zinc and Copper. By Edgar F. Smith. Copyright, 1902, by William A. Noyes, Chairman of the Committee on Papers and Publications of the SINCE the beginning of these experiments in the early summer of 1898, many contributions have been made toward the better understanding of the various problems of plant nutrition. Among these, the nitrogen question has been receiving the attention of many investigators, and it has been examined from the different standpoints of the soil chemist, the soil physicist, and the soil bacteriologist. Much time and ingenuity have been devoted to the clearing-up of that phase of the nitrogen question known as "denitrification"-the destruction of the nitrates and the setting free of gaseous nitrogen. That deoxidation of combined nitrogen is liable to take place, and actually does take place in anaerobic fermentation, has been known for years, but the question assumed more than a mere scientific interest, since the emphatic declaration of Wagner1 that applications of cow or horse manure to the soil are often not only unprofitable, but harmful; that, when applied together with the nitrates, they cause, by virtue of the microorganisms contained in them, the destruction of the nitrates. More than that, the baneful effects do not stop here, for the nitrates as they are gradually formed from the organic matter of the soil are also attacked by the denitrifying bacteria, and their nitrogen is set free. In a word, then, the animal manure applied is not only useless of itself, but is harmful because of its destructive effects on the oxidized nitrogen derived from other sources. It is quite apparent that the interests involved are of great moment, that Wagner's theory if it be borne out by practical experience vitally concerns the man of science, the practical farmer, and the world at large. It was in the hope of contributing something to the knowledge of the subject that these experiments were planned. The scope of the work included the study of: I. The composition of the solid and liquid portions of cow manure, fresh. II. The composition of the solid and of the solid and liquid portions of cow manure, leached. III. The availability of the nitrogen in the solid and in the solid and liquid portions of cow manure, fresh. IV. The availability of the nitrogen in the solid and in the solid and liquid portions of cow manure, leached. V. The relative availability of the nitrogen in the form of nitrate, of ammonia and of organic matter in dried blood. VI. The effect of the use of the solid and of the solid and liquid portions of cow manure, fresh and leached, with nitrogen in the form of nitrate, of ammonia, and of organic matter. DESCRIPTION OF THE EXPERIMENTAL PLANT. In order that the conditions of the experiment might conform as nearly as possible to those in actual practice, what is known as the "cylinder method" was adopted. The cylinders were made of galvanized iron, 23.5 inches in diameter and 4 feet long, and were painted inside and out, to retard corrosion. The area of soil surface thus exposed was, therefore, 3 square feet, and its depth was such that the roots of the crop would be practically prevented from obtaining food other than that contained within the cylinders. In order that the conditions for each cylinder might be uniform, the surface soil was first removed entirely, and the subsoil, a mixture of clay and sand, |