SOILS — FERTILIZERS. 415 



Chem. 8oc. [London'i, 106 (1914), No. 617, II, p. 169).— This is a modified form 

 of Beckmami apparatus. "The cooling batli is large, and consists of two con- 

 centric glass cylinders, the inner one 17 by 27 cm., and the outer 23 by 30.5 cm. 

 The copper cover is replaced bj' a thick plate of ebonite. The freezing tube is 

 round at the closed end, and is sui'rounded by a two-walled Dewar vacuum tube. 

 The part projecting above the ebonite cover is protected by a wooden air cham- 

 ber to prevent change of temperature." Cooling is promoted by immersing in 

 a wide test tube containing mercury coolod to a suitable temperature. 



The results of a series of experiments on a sample of milk are given. 



The influence of am.inonium sulphate upon the specific rotation of lactose, 

 R. RosEMANN (Hoppe-Scijler's Ztschr. Physiol. Chcm., 89 {1914), No. 1-2, pp. 

 133-l-'f0). — The results show that the specific rotation of lactose is reduced when 

 ammonium sulphate is present and that the reduction increases with a corre- 

 sponding increase of ammonium sulphate to the solution. In a solution satu- 

 rated with ammonium sulphate the rotation is reduced from 52.53 to 50.47°, 

 and in the Salkowski method (E. S. R., 27, p. 506), which employs a solution 

 with 40 per cent ammonium sulphate, from 52.53 to 51.55°. With a solution 

 containing from 4 to 6 per cent of lactose the results will consequently appear 

 from 0.07 to 0.11 per cent too low, which corresponds to the figures found by 

 Jahnson-Blohm, i. e., 0.08 to 0.14. As Kretschmer found values which were 

 generally higher with the Salkowski method it seems advisable to make no 

 corrections at all. 



On the estimation of fat in feces, F. C. Gephaet and F. A. Csonka (Jour. 

 Biol. Chem., 19 (1914), No. 4, pp. 521-531, fig. J')-— The proposed method is said 

 to be time saving and to yield good results with feces for fat or cholesterol 

 ester determinations. 



" Weigh out finely powdered or well mixed moist sample. Saponify with 



KOH in alcohol (4 gm. of stick KOH and 20 cc. of 95 per cent alcohol). Dilute 



with 50 cc. of water and acidify with HCl (20 cc. of 20 per cent in 5 cc. 



portions). Shake out with ether and wash ether extract. Distil oft ether and 



N 

 dry fatty acids. Take up with petroleum ether, filter, and titrate with 



alcoholic KOH. Calculation : 



CC.^X0.0296 



X100=per cent tristearin. 



10 



Weight of substance taken 



" By the Liebermann-Szekely method one determines a small amount of 

 cholesterol with the fatty acids. The Kumagawa-Suto method is laborious 

 and difficult of manipulation, and does not yield good results with pure fats 

 or cholesterol esters." 



A volumetric method for the estimation of total sulphur In urine, G. W. 

 Raiziss and H. Dubin (Jour. Biol. Chem., 18 (1914), No. 2. pp. 297-^03) .—This 

 volumetric method has for its basis the estimation of the precipitate of benzidin 

 sulphate rather than of sulphuric acid. Benzidin in an acid medium reduces 

 potassium permanganate quantitatively with the instant production of a canary- 

 yellow product which on further oxidation is converted into a colorless sub- 

 stance. With the method very small amounts of sulphate may be accurately 

 determined in a short time. 



SOILS— FERTILIZERS. 



Lake County soils, C. G. Hopkins, J. G. Mosiee, E. Van Alstine, and F. W. 

 Garrett (Illinois Sta. Soil Rpt. 9 (1915), pp. 52, pi. 1. figs. 9).— This is the 

 ninth of the series of the Illinois county soil reports and deals briefly with the 



