AGRICULTURAL CHEMISTRY. 9 



The commercial analysis of cane molasses. I, Optical methods, II I . 

 Sawyeb (Jour. Amer. Chem. Soc, 21 (1905), No. 6, pp. 691 713, dgm. 1). In the 

 method previously proposed by the author Eor dark materials the normal weighl of 

 molasses 26.048 gm. is made up to a volume of 500 cc. instead of LOO cc, a~ cus- 



t ary. This method has been tested by the nut Inn- for 4 years, and while no claim 



is made thai precision is attainable, it is believed to be very suitable for practical 

 purposes. 



Different methods of fat determinations in milk, K. Fhiis, E. Holm, and 

 A. Y. Khakii' (Ber. K. Vet. <><j Landbohbjskolea l.<0>. Landbkonom. Fors'dg [Copen- 

 hagen], 56 I 1905), />/'. l 28). The report gives the results ei' an investigation of the 

 reliability ami comparative value <>t' the extraction method of milk analysis and the 



Gottlieb-Rose method. The errors of analysis found in the case of the former 

 method are of especial importance in the analysis of skim milk and buttermilk, in 

 the ease of which it may give from 0. 1 to 0.2 per cent too low results. 



Tin- "sin-acid" method of fat determination in milk was also studied, the results 

 showing that ordinary mixed milk containing formalin in the proportion of 1:2,000, 

 if left for BOme time ( 14 days), will give too low results; also that the method is not 

 applicable to analysis of skim milk and buttermilk. A- the "sin-acid" method 

 has. however, been modified since this work was done, it is felt that the method 

 must still be considered in the experimental stage. — v. w. woll. 



The new method of determining- fat in milk, Sichler's kt sin-acid" butyro- 

 metry, G. Cornalba (Staz. Sper. Agr. It<i/., 38 (1905), No. 3, pp. 227-240). — Com- 

 parative determinations by the Sichler and Gerber methods are reported. The 

 results agreed very closely. The advantages and disadvantages of the new method 

 are pointed out. 



Detection of added water in milk, Utz (Milchw. Zentbl., I (1905), No. • <, pp. 

 909-211 ). — The author discusses the detection of water in milk by means of tests for 

 nitrates and by the index of refraction. The disappearance of nitrates in milk when 

 added in water was believed to he associated with the development of lactic-acid 

 bacteria, which could of course he lessened by pasteurization. It is believed that 

 heating milk has no effect on the index of refraction. 



Table for computing the total solids and the solids-not-fat in milk from 

 the specific gravity and the fat content according to the Fleischmann for- 

 mula, Ki'-iTNKK and Ulrich [Milch. Ztg., 34 (1905), No. 18, pp. 214, 215). 



Contributions to the examination of butter, M. Siegpeld (Milchw. Zentbl., I 

 I 1905), No. 4, />/>■ 155-171 ). — The author reviews recent investigations relating to the 

 methods of butter analysis and reports determinations of the Eteichert-Meissl, Po- 

 lenske, saponification, and iodin numbers and the mean molecular weighl of the 

 volatile and nonvolatile fatty acids in a number of samples of butter from 2 large 

 dairies. 



The results are discussed at some length as regards the value of the different deter- 

 minations in detecting adulteration. While the addition of cocoanul fat to butter 

 may be detected by means of the methods of Juckenack, Polenske, and Bomer, it is 

 not believed that there is at present a satisfactory method for the positive detection 

 of the addition of animal fats. 



The extraction of tanning materials with various extractors, F. P. Veit it 

 (Jour. Am,,-. Chem. Soc, 21 (1905), No. 6, pp. 724-729,fig. 1).— This paper, which 

 was presented before the Association of Official Agricultural Chemists at its meeting 

 in 1904 ( K. S. R., 1(1, p. ",2s t, L dves the comparative results ohtained on different 

 materials with 3 extractors. 



The determination of ash in plant substances, E. Gutzeit (Chem. Ztg., 29 

 {1906), Xo. 40, p. 556). — The method of incineration with hasic calcium phosphate 

 first proposed by Ritthausen is described. 



