RECENT WORK IN AGRICULTURAL SCIENCE. 



AGRICULTURAL CHEMISTRY. 



A revision of the atomic weight of potassium, T. W. Richards, A. Staehler, 

 and E. Mueller (Jour. Amer. Chem. Soc, 29 (1901), No. 5, pp. 623-656).— 

 Ueterminations based upon the analysis of potassium clilorid and bromid are 

 reported. These agree in showing that the atomic weight of potassium is 

 :}0.1U. 



A new method of determining the alkalinity of ashes, K. Farnsteiner 

 {Zisrhr. Untersuch. Nahr. u. Genussmtl.. 13 (1907), pp. 305-338; ahs. in Analyst, 

 32 (1907), No. 37. 'i, p. 181). — In the method proposed the ash is dissolved in a 

 known volume of standard acid, phosphates are precipitated by the addition of 

 calcium chliirid and a kntnvn quantity of ammonia, and the excess of annnonia 

 is then titrated back. The results obtained by this method are usually much 

 lower than those yielded by direct titration. 



Methods of examining milk and milk products, C. Barthel (Die Mcthodeii 

 :.iir r)itri:suchuiii/ roii Milch mid Molkercipl-oduJden. Leipsic: M. Heinfiius, 1907, 

 PI). ] 11+271. litis. 59: ahs. in Rev. Q6n. Lait, 6 (1907), No. 8, pp. 185-187).— 

 This is a complete treatise on the analysis of milk and its products. The chap- 

 ters deal successively with the examination of milk, butter, cheese, milk products, 

 and tlie decomposition i)roducts of milk, butter, and cheese. 



On the methods of determining fat in milk, M. Beau (Lait. et Indus. Fcrme 

 [Paris], 17 (1907), No. 8, pp. 57-60).— The relative values of the practical and 

 more technical laboratory methods of determining fat in milk are discussed, 

 rreffrcnco is exitressed for the Rose-Gottlieb method. 



Tests of the salt method, K. Jaross (Milch tr. Zcntbl., 3 (1907), No. 5, pp. 

 185-199). — The (Jerber salt or alkali method for determining milk fat was com- 

 I)ared with the Gerber acid method and also with the Gottlieb method and the 

 (lata so obtained are used as a basis for a discussion of the various advantages 

 and disadvantages of the salt method. 



Notes on the determination of total solids in milk and on formulas used 

 in milk control, I'. Gobert and M. Bouin (Rev. Gen. Lait. 6 (1907), Nos. 9, 

 pp. 193-2011: 10, pp. 22.'i-230). — The various methods of determining or of cal- 

 culating by means of fornuilas the solids in milk are discussed, emphasis being 

 laid upon the importance for purposes of milk inspection of determining the fat 

 rre(» extract or the ratio of fat to total solids. 



The detection of cocoanut oil in butter, E. Hinks (Analyst, 32 (1907), No. 

 37.}, pp. 160-162). — The method described depends upon the formation of needle- 

 shaped crystals by cocoanut oil. It is as follows: The melted and filtered fat is 

 dissolved in ether and the solution cooled. The solid glycerids separate out in 

 about one-half hour, leaving a clear ethereal solution which is filtered and 



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