716 EXPEEIMElsrT STATION RECOED. [Vol.35 



the soil which will only grow scrub shows more magnesia than lime by both 

 methods, as, similarly, does the soil which will not grow anything." It is 

 indicated that " it may be ultimately found . . . that the 1 per cent citric-acid 

 method . . . may prove a means of diagnosing an injurious excess of mag- 

 nesia in soils." 



A rapid method for the estimation of calcium oxid in peat soils, R. A. 

 GoETNER {Soil Sci., 1 (1916), No. 5, pp. 505-508). — In connection with some 

 work on peat soils at the Minnesota Experiment Station the author devised 

 the following procedure for the determination of calcium in peat : 



Five gm. of peat is incinerated in a quartz dish, the ash digested with aqua 

 regia, evaporated to dryness to dehydrate the silica, the residue taken up with 

 dilute acid, filtered into a 500 cc. flask, and made to volume. To 100 cc. of 

 this solution enough ammonia is added to make the liquid smell strongly 

 and to precipitate the iron and aluminum. The liquid is brought to a boil, 

 and while boiling 10 cc. of a saturated solution of ammonium oxalate is added. 

 The calcium oxalate is thus precipitated over the surface of the iron hydroxid, 

 making the latter more or less granular, and greatly aiding filtration and 

 washing. The boiling is cautiously continued for a few minutes and the 

 solution allowed to cool. 



After at least three hours, or preferably overnight, the solution is filtered 

 and well washed with warm water. When the precipitate is completely 

 washed, the beaker in which the precipitation was made is placed under the 

 funnel, a hole punched in the filter paper, and the precipitate washed into 

 the beaker with a stream of warm water. The filter is then well washed 

 with a hot 1.5 per cent sulphuric acid solution, 10 cc. of concentrated sul- 

 phuric acid is added to the washings, the solution brought nearly to a boil, 

 and the oxalate titrated with a standard potassium permanganate solution 

 of such strength that each cubic centimeter is equivalent to 0.001 gm. of 

 calcium oxid. 



Analytical data submitted indicate the accuracy of the procedure. The 

 method is not applicable to mineral soils, the results being consistently high. 



A rapid method for the estimation of fat in powders, S. B. Phillips 

 (Analyst, 41 (1916), No. 1/82, pp. 122, 123, fig. i).— The author describes a spe- 

 cially devised apparatus for use in the estimation of fat in powders, using 

 trichlorethylene as a solvent. The method is similar in principle to the pro- 

 cedure described by Neumann (E. S. R., 26, p. 507) and is claimed to yield ex- 

 cellent results. 



The determination of sucrose in cane products by direct polarization, 

 using a new method for the destruction of the reducing sugars, C. Muller 

 (Internat. Sugar Jour., 18 (1916), No. 210, pp. 27^, 275).— For the destruction of 

 reducing sugars in the determination of sucrose in cane products by direct 

 polarization the author describes the following procedure : 



A reagent is prepared by dissolving 25 gm. of Rochelle salt and 32 gm. of 

 sodium hydroxid in 400 cc. of distilled water. To this, after heating slightly to 

 effect solution, is added 11 gm. of bismuth subnitrate, heating being continued 

 to dissolve the salt, after which the solution is cooled, made up to 500 cc, 

 mixed, and filtered. 



To use this reagent for the destruction of reducing sugars in the case of a 

 cane molasses 20 gm. is diluted with 40 cc. of boiling water, 10 cc. portions of 

 this dilution being poured on the weighed sample at a time, or 50 cc. of a 

 solution containing 20 gm. of the molasses may be used. The liquid is placed 

 in a 300 cc. flask, 15 cc. of the bismuth reagent added, and the mixture heated 

 in a boiling water bath for 15 minutes. The liquid is then cooled, 150 cc. of 

 cold water and the equivalent of 60 cc. of basic lead acetate of the density of 



