CHEMISTRY. 941 



Analysis of milk and dairy products {Xord. Mejeri Tidu., IS {190J), Xn. 11, 

 p. 142). — Official methods of analysis adopted by the Agricultural Department of 

 Sweden for the State and County Chemical Control Station. — v. w. woll. 



The determination of the percentage of water in butter {Jour. Dept. Agr. 

 and Tech. Instr. Ireland, S {1902), No. l,pp. <9~'-9,^).— This discusses different methods 

 of sampling and analysis and gives the results of comparative tests. The most satis- 

 factory method of sampling was the use of a large trier thrust vertically through the 

 bulk of the butter, the core so obtained being placed in a glass-stoppered bottle, 

 melted, shaken, and afterwards cooled. Of the ordinary analytical methods for 

 determining moisture the use of a flat-bottomed porcelain dish and pumice stone is 

 considered the most accurate, the details of mani])ulation as recommended for 

 creamery and factory managers being given. 



The application of Wollny's refractometer to the determination of the fat 

 content of skim milk, C. Bartiiel {Nord. Mejeri Tkln., 18 {1903), No. 6, p. 71). — 

 Comparisons of determinations of the fat content of 184 samples of separator skim 

 milk liy the refractometer and Gottlieb's methods led to the conclusion that the for- 

 mer method is well adapted for use where a large nundicr of determinations are to 

 be made. The average difference of the determinations by the two methods was 

 0.01 per cent, a difference of 0.05 per cent occurring in 2 cases, 0.04 jm r cent in 5 

 cases, and 0.03 per cent in 17 cases. Thirty-eight comparative dctcrniiiiations were 

 alike. — f. w. woll. 



Methods of incineration for determining chlorin in animal solutions and 

 organs as well as in foods, C. Strzyzowski {Oc^terr. Chem. Ztg., 6 {1903), ^jp. 

 25-28; ahs. in Chem. Centbl., 1903, I, No. 10, p. 601).— In the method proposed the 

 substance is dried and carefully incinerated in presence of magnesium oxid (1 gm. to 

 20 cc. of solution or 10 gm. of the solid substance moistened with 10 to 15 cc. of 

 water). The product thus obtained is dissolved in the exact amount of sulphuric 

 acid required for complete solution and the chlorin is determined by titration accord- 

 ing to the Mohr method. 



The chemistry of plant and animal life, H. Snyder {Ea.Mon, Pa.: Clieniical 

 Pub. Co. P/T.S.S, 1903, pp. XVJI + 406,fgii. i05').— This volume, which is designed as 

 a text-book suitable for the instruction in chemistry of students in agricultural col- 

 leges, contains chapters on the foundation princi2:)les of chemistry, the chemistry of 

 plant growth, the composition of plants, feeding value of different crops, rational 

 feeding of animals, and related topics. In every case the explanations are full and 

 clear, and the volume should i5rc)ve a useful handbook, especially since the subjects 

 presented and the methods of treatment are such that the relations of chemistry to 

 everyday life are emphasized. 



Text-book of agricultural chemistry, A. Mayer {Lehrbuch der Agrikultur- 

 chemie. Heidelberg: Carl Winter, 1902, 5. rev. ed., vol. 2, pt. 2, pp. VI+253, figs. 3).— 

 This is the second and concluding part of the second volume of the fifth revised 

 edition of this work (E. S. R., 13, p. 913). The first part of this second volume 

 deals with soils; the second part is devoted to fertilizers. The third and last volume 

 of this work, which is now in course of preparation, deals with the chemistry of 

 fermentation. 



The application of the equilibrium law to the separation of crystals from 

 complex solutions and to the formation of oceanic salt deposits, I"-. F. Arm- 

 strong {Bpt. British J.s.soc. Adr. Sci. 1901, i)p. 262-282, figs. ,5).— This is a i)aper com- 

 piled from a series of 23 papers by van't Hoff and his pupils (E. S. R., 14, p. 430), 

 published since the year 1897 in the proceedings of the Berlin Academy of Sciences. 

 The author states that "apart from these and the information given by van't Hoff in 

 his text-books, there are only two other papers bearing on the subject— one by van 

 der Heide,« the other by Lowenherz."& 



«Ztschr. Physikal. Chem., 12 (1893), p. 416. 

 ftZtschr. Physikal. Chem., 13 (1894), p. 459. 



