712 EXPERIMENT STATION RECORD. 



sulphate takes place in a few minuter, the color gradually diffusing through the 

 liquid. If no formaldehyde is present, the liquid at once becomes brown, rapidly 

 changing to black. The test is sensitive to 1 part formaldehyde in 250,000 parts of 

 milk. 



The preservation and analysis of milk samples, M. A. Dubois {Rer. Internal. 

 Fnlsif., 14 {1001), No. 2, pp. 42, 43). — A discussion of preservatives and methods of 

 analysis. 



Quantitative estimation of the fat in milk by means of water-free sodium 

 sulphate, O. Le Comte {Jour. Pharrii. et Chim., 6. ser., 13 {1901), No. 2, pp. oS-fJO; 

 ah. in Ztschr. Unlersuch. Nahr. n. Genussmtl., 4 {1901), No. 19, p. 897). 



The estimation of volatile fatty acids in butter by the Lieffmann-Beam 

 method, H. LtJHRiG {Molk. Ztg., 15 {1901), No. 30, pp. 535-527).— Vvom a study of 

 tiie method the author found that the variations in the amount of sulphuric acid 

 added had but little influence upon the Reichert-Meissl nunil)er obtained. 



The detection of cocoanut oil in oleomargarin and in butter, W. G. Indemans 

 {Rev. Internal. Falsi/., 14 {1901), No. 2, pp. 39-41). 



The adulteration of fatty oils with mineral oils and its detection, E. Gold- 

 berg {Farmaz. Gotmi., 40 {1901), p. 375; abs. in Cliem. 7Ag., 25 {1901), No. 50, pp. 

 191, 192). — The author quotes a series of analyses of 101 olive oils of which only 19 

 were unadulterated. To 10 there had been added foreign vegetable oils and to 72 

 mineral oils. Of 130 samples examined by the author in 1900, 22 were a<lulterated 

 with vegetable oils and 54 with mineral oils. With the latter, some contained as 

 much as 30 to 50 per cent of mineral oil. The adulterant was generally a Russian 

 Baku naphtha of 300°. The determination of the adulteration in this case depends 

 upon the fact that this mineral oil is not saponified with alkali. 



Modification of Milliau's reaction for sesame oil, G. Armani {Ann. Lab. Chim. 

 Gabelle, 4 {1900), pp. 237-248; abs. in Ztschr. Untersvrh. Nahr. u Genussmtl, 4 {1901), 

 No. 10, p. 4<il)- — The following modification is given for showing the presence of 

 cotton-seed oil in mixtures without giving a coloration with certain kinds of olive 

 and crucifer oils: Ten gni. of the oil is saponified with alcoholic potash, the alcohol 

 evaporated, the soap dissolved in water and shaken in a separating funnel with 100 cc. 

 ether and 30 cc. of 10 per cent hydrochloric acid. The ethereal solution is washed, 

 the ether evaporated, and the resi<lue dissolved in alcohol which lias been purified by 

 treating with potassium hydroxid and redistilling. The alcoholic solution is treated 

 with 1 cc. of 5 per cent silver nitrate solution and immersed in a water ]>ath at 80°. 



The Hiibl iodin solution, INI. Kirr {Chetn. Ztg., 25 {1901), No. 50, p. 540).— A 

 study of the Hiibl iodin number by the Wijs method. 



Results of the heating of vegetable oils and methods of determining the 

 admixture of other oils, M. Tortelli and R. RrooERi {Monit. Sci., 4- ser., 15 

 {1901), pp. 865-37 5; abx. in Chem. Centbl., 1901, II, No. 1, ])p. 59,60).— Uesults of 

 trials of various methods. 



The use of the refractometer in the analysis of waxes, P. Prosio {Staz. Sper. 

 Agr. Ital, 34 {1901), p. 122; abs. in Chem. Ztg., 25 {1901), No. 60, p. ^^i).— The author 

 employed the Zeiss refractometer in the examination of pure and adulterated waxes, 

 both white and yellow. The temperature of 64° C. was used in all caseF. The refrac- 

 tometer number of the pure waxes fell between 30 and 32, mostly between 30.5 and 

 31.5, while waxes adulterated with stearin or paraffin fell below 30. The addition 

 of 5 per cent of steai-in may be detected, but ceresin only when above 15 per cent \t 

 present. With the addition of rosin or carnauba the refractometer number ranged 

 above 32. 



Comparative analysis of beets by hot-water digestion and instantaneous 

 diffusion methods. L. S. Marsh {Beet Sugar Gaz., 3 {1901), No. 7, p. 158).— The 

 comparison of results with 20 samples showed an average 0.43 per cent higher for 

 hot-water digestion. 



