ordinary care the errors can be kept inside of limits which allow the use of the method for nearly all practical purposes" he did not "see any reason why the same should not be given a place alongside of the molybdic method."

B. B. Ross reported the results of comparisons of the direct and dif ference method for reverted phosphoric acid. The direct method has given good results in his laboratory, but has not proved altogether satisfactory in the hands of other chemists.

H. A. Huston stated that it was almost impossible to obtain chemically pure phosphates for check tests. The phosphates of silver and of zinc were apparently the purest with which he had experimented. He reported that he was endeavoring to work out a volumetric method, using sulphuric acid throughout instead of nitric acid. He displayed a number of charts showing the influence of variation in the amount of solvent, temperature, etc., on the amount of citrate-soluble phosphoric acid.

B. B. Ross displayed a model of a mechanical stirrer driven by an electric motor for use in determining phosphoric acid, stating that it had been successfully employed in his laboratory.

Very slight changes, chiefly of a verbal character, were made in the methods for phosphoric acid, the principal modification being a provision for the washing of the final precipitate with 24 per cent of ammonia. until free of chlorids, and igniting the precipitate until white or grayish white before weighing. It was directed that Kilgore's volumetric method be published, and that the various chemists be given an opportunity to test it during the coming year with a view to its adoption at the next convention of the Association. The reporters were also requested to further investigate the citrate method of phosphoric acid determination.

(3) Nitrogen.-A report of tests by 11 chemists of the official and Fassbender methods for total nitrogen and of the Ulsch and zinc-iron methods for nitric nitrogen was presented by J. M. Bartlett. With very few exceptions the results were concordant and furnish strong evidence of the reliability of the methods.

In the discussion following the report J. B. Lindsey stated that an error may be introduced into the Ulsch method by not using enough. magnesium oxid and not distilling long enough. He also spoke of the difficulty of preventing alkali from being carried over into the distillate in the zinc-iron method.

H. C Sherman presented a paper on the determination of nitric nitrogen, in which he reported results highly favorable to the Ulsch method.

A paper by S. H. T. Hays, on the availability of nitrogen in mixed fertilizers, was read, giving at some length the results of tests of pepsin digestion, putrefaction, and distillation with permanganate of potash as in water analysis. The last method appeared to give the most promising results.

The Ulsch, Fassbender, and zinc-iron methods were referred to the reporters for further investigations. The only action taken with regard to the methods for nitrogen was the addition of the method of distillation with magnesium oxid for determining ainmonia.

Soils and ash.-The report on this subject was presented by A. M. Peter. This report gave data of chemical analyses of the ash of corn stover and of mechanical and chemical analyses by 14 chemists of samples of soil of known history, especial attention being given to methods of determining the availability of plant food in the soil. The latter included digestion of the soil in 1 per cent citric acid for 5 hours with frequent thorough shaking; digestion for the same length of time in a solution of 6.3 gm. of oxalic acid in 1 liter of water; and digestion in the same manner in a solution containing 20 gm. of crystallized oxalate of ammonia and 2.15 gm. of anhydrous acetic acid. Goss's method, as well as present official methods for determining the amount of soil constituents soluble in strong acids, were also tested. Goss's method gave as a rule more satisfactory results than the ordinary methods, and it was adopted by the convention as an optional method of soil analysis. The results obtained in digestion with the weak acids were of such a character as to encourage the hope that a method may be developed along this line which will be fairly indicative of the actual conditions of soil fertility. A few changes of minor importance only were made in the methods of soil analysis.

A. Goss read a paper reporting the results of determinations of phosphoric acid and potash in soils, including studies of methods of preparing soil solutions and of quick precipitation of phosphoric acid at high temperatures. The data obtained in examinations of a number of different soils indicated that 1 hour's digestion with sulphuric acid, with the addition of mercuric oxid, gives the maximum solvent effect; and that 15 minutes at 80° C. is sufficient to precipitate all phosphoric acid from the soil solution.

H. J. Wheeler read a paper on the necessity for tests for acidity on upland or naturally well-drained soils, in which he called attention to the fact that well-drained soils which are unproductive on account of an excess of acidity are widely distributed and that lime is the corrective of this condition.

B. W. Kilgore reported the results obtained by himself and C. B. Williams in the determination of phosphoric acid in soils by double precipitation with molybdic solution (1) at 40° C. in a water bath with 30 cc. of official molybdic solution, and (2) at 35° C. in a water bath with concentrated nitric acid and 2 cc. of molybdic solution, the phospho-molybdate being titrated with standard alkali.

A paper by H. Snyder on the determination of total insoluble matter, phosphoric acid, lime, and potash in soils, which described in detail methods used by the author in soil analysis, was read by A. M. Peter, as well as a paper by H. Snyder and J. Thompson on the effect of the

presence of a small amount of nitric acid in the acid digestion of soils, which showed that the addition of a few drops of this acid resulted in a slight but constant increase in the amount of matter dissolved.

A paper by E. W. Hilgard on the recognition of "nitrogen hungriness" in soils was read by H. W. Wiley, which discussed present methods of determining the humus in soils as well as investigations of the nitrogen content of humus, the conclusion being drawn that soils containing humus in which the percentage of nitrogen was less than 2.5 are likely to need applications of nitrogenous fertilizers regardless of the total amount of nitrogen present.

M. Whitney discussed the importance of physical examination of soils. W. C. Stubbs called attention to the importance of the study of the physical properties of soils, especially on soils such as those occurring in some parts of Louisiana where fertilizer experiments have been practically barren of results. W. G. Brown questioned the utility of soil analysis as at present conducted.

Sugar.-E. E. Ewell reported on tests of methods of sugar analysis, especial attention having been given to the determination of moisture. Drying on pumice stone gave good results, but, as shown by R. C. Kedzie, the results vary with the amount of sample taken.

Numerous and extensive changes, many, however, of a verbal character, in methods of sugar analysis were recommended, and the recommendations of the reporter were adopted as a whole, the methods of sugar analysis being referred to the reporter and the secretary of the Association to be rewritten.

A paper giving the results of determinations of moisture in viscous organic solutions by drying on pumice stone, by O. Carr and T. F. Sanborn, was read.

Fermented and distilled liquors.-W. D. Bigelow reported on tests of methods for fermented and distilled liquors by 11 analysts. The principal change in method recommended was the discontinuance of the use of the mercury valve in the distilling apparatus and the determination and the subtraction of the ash in the method for glycerol. The rewriting of several paragraphs of the present methods was directed.

Feeding stuffs.-The report on this subject was submitted by H. J. Patterson. Attention was devoted during the past year principally to methods for crude fiber and for determining the constituents of nitrogenfree extract-dextrose, sucrose, starch, and pentosans. Sachsse's, Märcker's, and Stone's methods for starch were studied. Six analysts, including 2 foreign chemists, furnished reports, but in some cases these were only partial or contained results obtained by methods not originally outlined by the reporter. The data obtained in different laboratories were very discordant and generally unsatisfactory. It was decided that the present methods remain unaltered; that methods for dextrose and sucrose be further investigated; and that Sachsse's method for starch be official only for potatoes. Tollens and Flint's method for pentosans as modified by Krug is to be studied during the coming year.

J. B. Lindsey pointed out that little progress has been made in the improvements of methods of analysis of feeding stuffs and advocated abandonment of the attempt to improve the method for crude fiber, believing it better to attempt the separation of the various constituents of crude fiber along the same line as that followed in the study of nitrogen-free extract.

H. A. Huston reported briefly the results of a comparison of the action of various solvents on hay with the action of the digestive fluids of the animal.

A. S. Mitchell recommended that a committee be appointed to investigate the extent of adulteration of foods and the means taken to prevent it in different States with a view to formulating legislation on the subject. The recommendation was adopted by the Association, and a committee was appointed to investigate this subject and report at the next convention.

Dairy products.-No formal report on this subject was submitted. H. W. Wiley read a paper prepared by S. M. Babcock, discussing formulas for calculating solids-not-fat in milk, and by C. G. Hopkins and W. A. Powers on the determination of the acidity of milk and cream. The method proposed for the latter purpose was as follows: Dilute 25 cc. of milk to 250 cc. with boiling water, boil 1 to 2 minutes, add 2 cc. of 1 per cent phenolphthalein, and titrate with standard alkali.

Tannin.-W. H. Krug reported the results of comparisons by 8 chemists of the methods of determining the tanning power of a tannin extract. These results showed that the present hide-powder method is unreliable. The mercuric-oxid method is recommended for investigation during the coming year.

Report of committee on editing methods.-The committee on editing methods reported in detail a comprehensive and consistent plan of revision of methods.

Report of abstract committee.-A brief verbal report from the abstract committee was submitted by W. Frear, outlining the work accomplished by this committee and recommending current reports of abstracts.

Officers of the Association.-The officers of the Association elected for the coming year were as follows: President, B. B. Ross; vice-president, W. Frear; secretary, H. W. Wiley; executive committee, H. J. Wheeler and F. W. Traphagen.

The associate reporters in each case were advanced to the position of reporters, and the following associates were appointed: Phosphoric acid, L. H. Merrill; nitrogen, R. J. Davidson; potash, W. L. Hutchinson; soils and ash, W. G. Brown; dairy products, C. L. Penny; foods and feeding stuffs, F. W. Morse; fermented liquors, W. C. Blaisdell; sugar, L. W. Wilkinson; tannin, B. D. Westenfelder.

The abstract committee is as follows: E. W. Allen, chairman; C. L. Parsons, W. D. Bigelow, A. M. Peter, H. J. Patterson, W. H. Krug, B. W. Kilgore, F. W. Woll, and J. L. Beeson.

RECENT WORK IN AGRICULTURAL SCIENCE.

CHEMISTRY.

On the chemical determination of the agricultural value of phosphatic fertilizers, G. PATUREL (Ann. Agron., 21 (1895), No. 7, pp. 325–342).—This is the second paper by the author on this subject and reports results of determinations of solubility in 1 per cent citric acid of the phosphoric acid in various natural phosphates, including apatite, Somme phosphate, Navassa phosphate, coprolites, etc., and in such commercial products as bone ash, phosphatic slag, and precipitated phosphate. For purposes of comparison the results obtained by Grandeau, Petermann, and others in culture experiments with some of these phosphates are briefly summarized.

The conclusion is reached that the assimilability of the different phosphates by plants may be accurately measured by treatment with citric acid in the following manner: One gram of the finely ground phosphate is placed in a flask and 500 cc. of a solution containing 5 gm. of crystallized citric acid is added. After 24 hours, during which the mixture is shaken as frequently as possible, a portion of the solution is filtered off and phosphoric acid determined. At the same time a determination of total phosphoric acid is made. In case of phosphatic slags the citric acid solution is added little by little and allowed to filter through the finely powdered slag in order to remove at the beginning the larger part of free lime and silicate of lime.

On the determination of nitric nitrogen in presence of organic nitrogen, T. PFEIFFER and H. THURMANN (Landw. Vers. Stat., 46 (1895), pp. 1–20; abs. in Jour. Chem. Soc. London, 1895, Sept., p. 369; and Chem. Ztg., 19 (1895), No. 62, Repert., p. 214).—Schlössing's method (reduction with ferrous chlorid) and the method of reduction with zinc dust in alkaline solution gave unsatisfactory results when tested on samples of manure or urine to which known amounts of nitric nitrogen had been added. The method finally adopted after numerous experiments was as follows: To the solution1 in a Lintner pressure flask add about 10 gm. of caustic soda and heat at 120 to 130° C. for about 8 hours. Allow the contents of the flask to cool and decant the solution into a distilling flask, the solid residue being washed on a filter and dried. Add a further quantity of soda to the solution and boil until no more ammonia

1 Fifty cubic centimeters of solution was used in the test reported.