12 EXPEBIMENT STATION RECORD. 



digested, preferably in a platinum dish, with hot water until it is resolved into 

 a loose condition. 



The residue, insoluble in water, is removed by filtration, and the calcium 

 in the filtrate is precipitated with ammonium hydroxid and ammonium car- 

 bonate. As the precipitate occupies a comparatively large space, it is redissolved 

 in dilute hot hydrochloric acid and reprecipitated with ammonium hydroxid and 

 ammonium carbonate. The combined filtrates are evaporated to dryness, and 

 after driving off the ammonium salts with the aid of heat, the residue is dis- 

 solved in the smallest possible amount of water. The last traces of calcium are 

 precipitated from this solution in a platinum dish with ammonium hydroxid 

 and ammonium carbonate, allowed to stand for several hours, and filtered into 

 a small tared platinum dish in which the alkalis, after removing the ammonium 

 salts, are weighed. The potassium is then determined as potassium platinic 

 chlorid, and from the difference the sodium is calculated. 



Tests were made for the purpose of determining the amount of potassium and 

 sodium in calcium chlorid, and some other tests to determine whether the alkali 

 chlorid contained calcium, magnesium, or sulphuric acid. 



The J. Lawrence Smith method gave lower results, but the author's method 

 was easy to conduct. 



New methods for the examination and judg-ment of soils, J. Konig {Abs. 

 in Ztschr. Angeiv. Chem., 25 {1912), No. 39, pp. 2001, 2002).— The methods men- 

 tioned are chiefly those already noted in the literature, namely, the determina- 

 tion of the catalytic power of soils and the nutrients made soluble by treatment 

 with steam under pressure (E. S. R., 17, p. 1138) ; determination of the inor- 

 ganic nutrient substances which can be liberated as a result of oxidizing humus 

 (E. S. R., 19, p. 718) ; influence of a strong constant electric current upon the 

 soil; determination of the osmotic pressure (E. S. R., 21, p. 409; 26, p. 217), 

 and the electrical conductivity of the soil (E. S. R., 24, pp. 521, 522; estimation 

 of the amount of colloids in soils (E. S. R.,' 26, p. 519) ; the use of dialysis in 

 the examination of soils ; and determination of the oxidizing capacity of the soil. 

 At present the author is engaged in separating the components of the soil 

 with solutions of various specific gravities, i. e., mixtures of bromoform and 

 benzol, specific gravity 2.65, 2.5, 2.4, 2.3, etc. These results will be reported upon 

 later. See also a previous note by May and Gile (E. S. R., 21, p. 220). 



The determination of lime in cow feces, R. A. Dutcher (Jour. Indus, and 

 Engin. Chem., 5 (1913), No. 1, pp. 37, 38). — It is maintained that methods of 

 ash analysis are very lax with reference to the acid treatment of the ash. The 

 author was unable to find anything in the literature in regard to the analysis 

 of the ash in cow feces. He suggests that " the ash be boiled at least 3 hours 

 with concentrated nitric or hydrochloric acid, and that the acid-insoluble resi- 

 due be evaporated to dryness with dilute sodium hydroxid to break up all 

 silicates. This alkaline residue should then be taken up with dilute acid and 

 added to the original solution for analysis." 



Water analysis for sanitary and technical purposes, H. S. Stocks (London, 

 1912, pp. VIII+136, figs. 8). — This book deals with the physical, organoleptic, 

 and chemical (qualitative and quantitative) analysis of water. Among the 

 topics discussed are deleterious metals; gases contained in solution; standards 

 of purity recommended by the Rivers Pollution Commissioners; tabular view 

 of the standards for effluents adopted by various authorities; average compo- 

 sition of unpolluted water ; tension of aqueous vapor ; loss of nitrogen by evapo- 

 ration of NH4HSO3 and NH4H2PO4 ; Warington's method of estimating nitrates ; 

 and preparation of reagents required for water analysis. Several conversion 

 tables are included. 



