RECENT WORK IN AGRICULTURAL SCIENCE. 



AGRICULTURAL CHEMISTRY— AGROTECHNY. 



The relation of agricultural chemistry to agriculture and biology, F. 

 ScuRTi (Ann. R. Staz. Chim. Agr. Sper. Roma, 2. set:, 3 (1909), pp. 309-337).— 

 A paper read at the Rome meeting of the Italian Chemical Society in February, 

 1910. 



Yearly report on the progress in chemistry of foods and condiments, 

 H. KUTTENKEULER (CJiem. Ztg., 3J, (1910), Nos. .',S, pp. ■'/26-428; 49, pp. 437- 

 440). — A retrospect of the advances made in the chemistry of foods and related 

 branches during 1909. 



Innovations in analytical chemistry, C. Beger (Ztschr. Analyt. Chem., 

 49 (1910), No. 7, pp. 427-436, figs. 4)- — The author describes and presents illus- 

 trations of handy Innovations for preventing losses and other discrepancies in 

 the process of estimating nitrogen iu milk and feces, also a modified Kipp appa- 

 ratus, and a description of the use of the Ostwald thermoregulator for artificial 

 digestion tests. 



The uses of trichlorethylene in analytical chemistry, L. Gowing-Scopes 

 (Analyst, 35 (1910), No. 411, pp. 23S-245).—A description of the chemical, 

 physical, and solvent properties of trichlorethylene, specific gravity 1.47, boil- 

 ing point 88° C. It is a colorless and noninflammable liquid. The article con- 

 siders its use for fat extraction in milk and foodstuffs analysis, etc. 



A comparison of Pozzi-Escot's and Devarda's method for the estimation 

 of nitrates, E. Cahen (Analyst, 35 (1910), No. 412, pp. 307, 308).— In the 

 Devarda method " the solution of the nitrate in water is introduced into a Jena 

 glass bulb flask together with 2 to 3 gm. of the alloy (Al 45, Cu 50, Zn 5) and 

 5 cc. of alcohol. The alloy must be sufficiently finely powdered to pass through 

 a 60 mm. sieve. Fifty cc. of concentrated alkali are added, and the flask quickly 

 connected to the Kjeldahl distilling apparatus and allowed to stand for 30 

 minutes, when the vigorous reaction will be complete. The contents of the flask 

 are then slowly raised to the boiling temperature, and steam is passed for 30 

 minutes, when all the ammonia will have distilled over into the receiver con- 

 taining the acid." The indicator employed was methyl-red. 



The method is considered superior to that of Pozzi-Escot (E. S. R., 22, p. 706). 



Determination of ammonia nitrogen in water in the presence of hydro- 

 gen sulphid, E. Bartow and B. H. Harrison (Jour. Amer. Chem. Soc, 32 

 (1910), No. 10, pp. 1256-1259).— The authors find that by adding sulphuric 

 acid to the water to be examined the ammonia is fixed, while the hydrogen 

 sulphid may be distilled off. The ammonia is then liberated with sodium 

 hydrate. This procedure has no influence on the other analytical results. 



The principles involved in the preparation of soil solutions for chemical 

 analysis, A. von 'Sigmond (//. Conf. Agrogeol. Tnternat. Stockhohn, 1910, 

 Resume [i], pp. 25-30). — According to the author, the methods of preparing the 

 soil solution constitute the nucleus of every soil analysis. He finds it imperative 



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