RECENT WORK IN AGRICULTURAL SCIENCE 



CHEMISTRY. 



Manual of agricultural chemistry, II. Ingle {London: Scott, Greenwood it- Co., 

 1902, pp. 388, fiys. 11) . — This volume " ih based upon lectures delivered annually, for 

 several years past, by the author, to classes of agricultural students, many of whom 

 iiad already acquired some knowledge of general chemistry. . . . In all cases the 

 w riter has endeavored to avoid empiric statements, and to give, as far as possible, an 

 explanation of the facts or phenomena described." The introductory chapter deals 

 with the distribution and relative abundance of the elements. Other chapters dis- 

 cuss the composition of the atmosphere, the materials from which soils are formed, 

 the agencies active in soil formation, the constituents of soils as related to their 

 chemical and physical properties, and the classification of soils; the reactions occur- 

 ring in soils (chemical, physical, and biological nitrification, denitrification, action of 

 gases and water, and electrolytic dissociation); analysis of soils (physical and chem- 

 ical); natural manures and commercial fertilizers; analysis and valuation of manures 

 and fertilizers; the constituents of the plant and the chemistry of the development 

 of its different parts, including explanations of the assimilation of carbon dioxid 

 through the stomata of the leaves based upon the generally accepted kinetic theory 

 of gases, and of the essential differences between osmoses and diffusion as related to 

 plant growth; the proximate composition of the principal farm crops (with methods 

 of analysis) ; the chemistry of the animal organism and of its functions; foods and 

 feeding; milk and its products (including analysis); miscellaneous products used in 

 agriculture, including arsenic, mercuric chlorid and various plant poisons, bleaching 

 powder, copper salts, iron sulphate, disinfectants, fungicides, and insecticides; and 

 an appendix of useful tables. 



Rapid volumetric m^ethod for determ.ining- phosphoric acid in fertilizers, 

 A. L. Emery {Jour. Amer. Chem. Soc, 34 {1902), No. 9, pp. 895-897).— A modifica- 

 tion of the volumetric method adopted by the Association of Official Agricultural 

 Chemists is described. The most important change proposed consists in shaking the 

 solution vigorously by hand after adding the ammonium molybdate. 



The determination of phosphoric acid by titration of ammonium phos- 

 phomolybdate, J. Cezar (Hnl. J.wor. Beige Chun., 16 {1902), pp. 247-253; aU. in 

 Chem. Centhl., 1902, II, No. 12, p. 820). — The author reports tests of Nyssens' method 

 (E. S. R., 13, p. 614) and describes slight modifications of certain details of it. 



On the determination of total phosphoric acid in Thomas slag, C. Aschman 

 {Chem. Zlg., 26 {1902), No. 71, p. <S"^'5).— The author describes a modification of his 

 method (E. S. E,., 11, p. 507), which consists in proceeding with the determination 

 immediately after obtaining the filtered solution of the slag, instead of allowing the 

 solution to stand 12 hours. 



On the influence of potassium ferrocyanid on the precipitation of phos- 

 phoric acid by ammonium nitromolybdate, A. F. Leuba (.1/;/;. Chhn. Analyt., 

 7 {1902), No. 7, p. 257). — It is shown that potassium ferrocyanid interferes with the 

 precipitation of phosphoric acid by ammonium molybdate, due to the fact that it 



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