1917] AGEICULTURAL CHEMISTRY ^AGEOTECHNY. 807 



presence of appreciable amounts of nitrogenous reducing substances (glutamin 

 and asparagin) is pointed out. The newer methods of inversion by double 

 fermentation with " top " and " bottom " yeast are considered to yield excellent 

 results and to be entirely reliable. Some analytical data are submitted. 



The estimation of pentose or pentosans by means of Fehling's solution, 

 J. L. Bakeb and H. F. E. Hulton (Analyst, J^l (1916), No. 487, pp. 294-297).— 

 The authors have used the method of Flohil as improved by Eynon and Lane 

 (E. S. R., 27, p. 113), and indicate as decided improvements in the procedure 

 the use of a much larger volume of Fehling's solution, in order that a con- 

 siderably larger fraction of the total distillate may be treated, thus increasing 

 the weight of CuO obtained, and, instead of boiling the solution, heating by 

 immersion in a boiling water bath. 



The values for the CuO equivalent of pure furfural found by Eynon and Lane 

 were confirmed. The figures for the CuO yielded from 20 cc. of Fehling's 

 solution with sodium chlorid alone were not in agreement. This discrepancy 

 in results, as well as the procedure in general, is briefly discussed. 



Determination of sugar in hay and turnips, R. K. Kristexsen (Tidsskr. 

 Planteavl, 23 (1916), No. 2, pp. 23S-250) .—Bet&iled tabular analytical data of 

 the sugar content of hay and turnips are submitted. From the data it is con- 

 cluded that the use of lead acetate with Fehling's solution for the determina- 

 tion of sugar introduces errors in the results. 



Control analyses were made with a solution of pure sucrose. 



The determination of fat in cacao products, W. Lange (Arb. K. Gsndhtsamt., 

 50 (1915), No. 1, pp. 149-157, fig. 1). — The author discusses the incomplete ex- 

 traction of cacao fat obtained with a Soxhlet apparatus, and describes a new 

 procedure for the determination. The procedure consists of extracting the 

 sample on a Witte plate with an asbestos filter by suction with small portions 

 of ether. The ether is then evaporated and the fat weighed in the usual 

 manner. The procedure requires considerably less time than the older method 

 of extraction and is deemed to be as satisfactory in every respect. 



Some experimental data are submitted. 



The alcohol test in milk, I. M. Kolthoff (Pharm. Weekbl., 5S (1916), No. 

 47, pp. 1589-1600). — The alcohol test in milk is considered to depend on the 

 calcium ions present. In normal milk the alcohol test (with 70 per cent 

 alcohol) appears when the acidity is equivalent to 7.8. In abnormal milk 

 there is no relation between the alcohol test and the acidity, but the test also 

 appears here with a comparatively low acidity. 



For the practical examination of milk, as well as from a hygienic and 

 pathological-chemical standpoint, the test is considered to be of great impor- 

 tance. If no flocculation appears the double test (using twice the amount of 

 alcohol) should be used. Flocculation in a sample of normal acidity probably 

 indicates an abnormal milk. As a check on the result the catalase index and 

 leucocyte content should be determined. 



The detection of added water in milk, H. Durand (Jour. Indus, and Engin. 

 Chem., 9 (1917), No. 1, pp. 44< 45)- — This is a brief review of the methods which 

 have been proposed for determining added water, namely, by the refractive 

 index of the serum, the freezing point of the whole milk, and the specific 

 gravity of the whole milk and serum. Some experimental data on the freezing 

 point method are included and discussed. 



The action of various animal charcoals on pure and impure sug'ar solu- 

 tions and their influence in the analysis of sug'ar refinery products, H. 

 Pellet (BuI. Assoc. CMm. Suet: et Distill., 3S (1916), No. 10-12, pp. 220-227).— 

 The results of experiments in which a number of charcoals were used in the 

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