416 EXPEETMENT STATION EECORD. 



For the actual soda content the limits set are as follows: First class, not more 

 than 0.05 per cent ; second class, 0.05 to 0.1 per cent ; third class, 0.1 to 0.2 per 

 cent ; and fourth class, 0.2 per cent and over. 



The modern understandings of ■weathering in the light of colloid chemistry, 

 F. CoRNu (Vonipt. Rend. Coiif. Intcinat. Af/m[/eol. [BudaiKst]. 1 {t!)U9), i)i>. 

 123-130). — The heterogeneous processes involved in weathering are briefly ex- 

 plained in the light of colloid chemistry. 



The unification of chemical soil analysis, E. W. Hilgard (Compt. Rend. 

 Conf. Internal. A(jro[/eoI. [Bndaije.st], 1 {1909). pp. 30.3-311). — A discussion of, 

 and a plea for, the unification of soil analysis. 



Methods of chemical soil analysis, K. Emszt {Compt. Rend. Conf. Internat. 

 Agrogeol. [Budapest], 1 (1909), pp. 219-223).^A description of the official 

 methods of the Association of Official Agricultural Chemists. 



Methods of soil analysis of the Royal Prussian Geological " Landesanstalt," 

 F. ScHUCHT {Compt. Rend. Conf. Internet. A(/ro(ieol. \Bitdapest\, I (1909). pp. 

 189-192). — A description of methods. 



Accuracy in taking and preparing mixed fertilizer samples, F. B. Porter 

 {Jour. Indus, and Engin. Cliem., 2 {1910), No. J,, pp. 1'/S-J.13, figs. 2).— The 

 author shows that much inaccuracy exists in the present methods of sampling 

 and preparing fertilizers for analysis, and that this ultimately results in dis- 

 crepancies which are much greater than those usually obtained in the laboratory 

 under noniial conditions. 



[Determination of ammonia by aeration], P. A. Korer {Jour. Amer. CJiem. 

 Soc., 32 {1910). No. 5, pp. 689-691). — It is stated that no ground exists for the 

 assertion of Grindley and Gill (E. S.R., 22, p. 303). that where relatively large 

 amounts of phosphorus and magnesium are present there is a retention of am- 

 monia. The error lies in the fact that too little allvali is used in liberating the 

 ammonia. 



The identification of fat from domestic animals used as food, poultry, and 

 game, by means of examination by physical methods, G. Kramer {Feststel- 

 lung der Untersuefiungsnterkmale der Fette der Heldaehtiiere. des Wildes und 

 Gefliigels durch rergleieJiendc pliysikaJische Untersuchungen. Inaug. Diss., 

 Univ. Gicssen, 1909. pp. 76; rev. in Zenthl. (lesrnn. Physiol, ii. I'dtli. Stoffweeh- 

 sels, n. ser., .'/ {1909), No. 23, p. 890).— As a result of his studies with the re- 

 fractometer. the author concludes that by the usual physical methods it is pos- 

 sible to determine definitely the origin of a given fat. 



About making an absolute extract estimation in barley, R. Seibriger 

 (Wehnsehr. Brau.. 27 {1910). No. 27, pp. 321-323. fig. 7).— The author describes 

 a modified method of absolute extract estimation, utilizing an apparatus termed 

 the •' barley disintegrator." 



Twenty -five gm. of the ground barley (fiour) is doughed in with 100 oc. of 

 water and 40 cc. of malt infusion (1 part malt -|- 4 parts water) and allowed 

 to stand in the disintegrator until the next morning, when the mixture is 

 broiight to a temperature of 110° C. and allowed to remain at this temperature 

 for 1 hour. The flame is then turned off, the temperature allowed to fall to 

 100°, and the blow-off valve carefully opened. The top of the apparatus is 

 unscrewed, the beaker taken out and cooled to 55°, and to this is added 60 cc. 

 of the malt diastase solution. The substance is then brought into the mashing 

 apparatus, the temperature raised in 10 minutes to 60°. allowed to remain at 

 this temperature for J of an hour (agitating during this time), heated to 70°. 

 allowed to stand at rest at this teni])erature for 15 minutes, and then stirred 

 for i hour until the saccharification is complete. After cooling, the contents are 

 made up to 225 gm. with distilled water and the specific gravity of the filtrate 

 taken with the pycnometer. 



An example for calculating the results is given. 



