806 EXPEBIMEXT STATIOI^ KECOED. 



Eeport of the session of the International Commission for Chemical Soil 

 Analysis; Munich, April 23 and 24, 1914 (Intermit. Mitt. Jiodenk., 5 (1915), 

 Nos. 1, pp. 25-52; 2, pp. 121-153). — This is an account of tlie proceedings of 

 the commission, including discussions of chemical methods for soil analysis. 



The application of potassium permanganate for the determination of 

 humus in soils, P. Grigokikff (Zhur. Opytn. Ayron., 16 (1915), .Vo. 3, pp. 217- 

 222). — The probable nature of the oxidation of the humus in soil by potassium 

 permanganate is considered. The results obtained by the oxidation method do 

 not agree with those obtained by Gustavsohn's method, the former method 

 yielding too high results. For this reason it is concluded that the oxidation 

 method, although simple and rapid, is not to be preferred to the combustion 

 method. 



On the distribution and composition of the humus of the loess soils of 

 the transition region, M. J. Blish (Univ. [Xcbr.] Studies, l.'f (1914), Xo. 2, pp. 

 lll-Ut-'f). — From a long series of experiments on Nebraska soils the author 

 concludes that the Rather method (E. S. R., 26, p. 406) for humus determina- 

 tions is the most practical of all gravimetric methods tried. I'or the determina- 

 tion of humus nitrogen the Alway-Bishop procedure was found to be the most 

 satisfactory, both in point of accuracy and economy of time. 



Soil color may be associated fairly closely with humus content when the 

 soils under inspection are from the same locality. A reliable comparison, 

 however, can not be made with soils from different localities on account of 

 the presence of substances other than humus, such as lime and iron. The 

 photometric determination was not found to give satisfactory results with soils 

 containing less than 0.1 per cent of humus. Great variation in the humus 

 content of the soils was found with respect to both locality and depth from 

 which the samples were taken. 



A comparison of methods for the determ.ination of soil phosphorus, W. Cs. 

 Robinson (Jovr. Indus, and Engin. Chcm., 8 (1916), A'o. 2, pp. 148-151). — The 

 results of the author's investigation indicate that accurate determinations can 

 be obtained by the fusion, Washington, and Fischer methods of treating the 

 soil for phosphorus determinations. Vanadium interferes with the volumetric 

 phosphorus determinations in soils, but the diflicultj' was overcome by reducing 

 the vanadium with ferrous sulphate and precipitating the phosphorus at a 

 low temperature by agitation. Tungsten and titanium were not found to 

 interfere with the phosphorus determinations by the gravimetric method when 

 proper precautions for complete precipitation were exercised. 



A limestone tester. C. G. Hopkins (Illinois Sta. Circ. 185 (1916), pp. 2-12, 

 figs. 2). — This circular describes in detail a simple apparatus and method for 

 the determination of calcium carbonate in limestones used for agricultural pur- 

 poses, similar to and based on the same principle as the " calcimeter " pre- 

 viously noted (E. S. R., 34, p. .'lOS). 



The final result can not be ascertained by direct reading hut involves a simple 

 calculation. Tables of the weight of carbon dioxid in milligrams per cubic 

 centimeter at various temperatures and pressures are included. 



The apparatus may also be used for determining the limestone content of 

 soils. 



Some new methods for the analysis of lime-sulphur solutions, R. M. 

 Chapin (Jour. huJns. and En-gin. Chrm., 8 (1910), No. 2, pp. 151-156). — ^>'ew 

 methods based on definite reactions are described in fletail. Some of the pro- 

 redures are applicable to polluted dipping baths through which sheep and cattle 

 have passed. 



On the detection and determination of halogens in organic compounds, 

 I. Drogin and M. A. Rosakoff (Jour. Amer. Chem. Soc, 38 (1916), Xo. 3, pp. 



