AGEICULTTJRAL CHEAnSTKY AGEOTECHNY. 109 



For extracting the total ammoniacal and soluble (assimilable) organic nitro- 

 gen, good results were obtained for high rooor soils with decinormal sodium 

 chlorid solutions used in the proportion of 20 or 40 : 1, for low moor soils fifth- 

 uormal sodium chlorid in the proportion of 10 : 1, and for mineral soils a one- 

 half-normal sodium chlorid in the proportion of 2 : 1 of solution to soil. 



In these extracts the ammoniacal nitrogen was first determined by distillation 

 with magnesium oxid, and the soluble nitrogen by the Kjeldahl method. Ni- 

 trate nitrogen was determined in the same extract by adding magnesium oxid 

 and some powdered alloy (prepared by fusing 60 parts of aluminum with 37 

 parts of copper and 3 parts of zinc) and heating. By this process the nitrate 

 is reduced to ammonia. Whore a lai-ge amount of organic matter was present 

 a small amount of sodium hydroxid was added for the purpose of stimulating 

 the reduction process. 



The organic nitrogen compounds present in the soils examined, which came 

 from Germany and Finland, consisted mainly of substances of a protein nature, 

 and for the most part nucleins. The solution of these bodies is brought about 

 by hydrolysis which results in the formation of amino acids and a mm onia from 

 the true proteins and from the nucleins certain nitrogenous compounds which 

 belong to other groups are formed. Some of the organic matter was found to 

 be hydrolyzed when the soil was merely boiled with water. 



It is further noted that considerable amounts of organic nitrogenous com- 

 pounds can be extracted from the soil by alkali solutions in the cold. The 

 hydrolysis of the nitrogenous compounds was found to decrease with the ex- 

 tent of the decomposition of the soil. The solubility of nitrogenous compounds 

 in diluted alkali solutions was higher for the more fertile soils. The nitro- 

 genous compounds present in the more decomposed moor soils were more stable 

 than those of the less decomposed moors. Those strongly decomposed contained 

 larger amounts of readily soluble nitrogenous compounds than the less decom- 

 posed soil. Since this can not be ascribed to the greater solubility or decom- 

 posability of the organic nitrogen compounds, it is apparent that the factors 

 which are active in stimulating the mobilization of the nitrogenous compounds, 

 namely, the micro-organisms, act more favorably in* the strongly decomposed 

 soils. 



At the beginning of this paper a historical sketch and a critical review are 

 given of the work reported by previous investigators. 



The chemistry cf honey, O. Haenle (Die Chemie des Honigs. Strassburg, 

 1911, 4. ed., rev., pp. 80. fig. 1). — A fourth edition of this work, which has for 

 its purpose the differentiation of real honeys from those adulterated with invert 

 sugar, glucose, or saccharose. 



Chemical changes produced in cows' milk by pasteurization, P. Rupp 

 (U. S. Dept. Agr., Bur. Amm. Indus. Bui. 166, pp. 15, fig. 1). — This investiga- 

 tion was undertaken because of the objections advanced from time to time 

 against pasteurization as injurious to milk from a digestive and nutritive 

 standpoint, especially as a food for infants. The points considered were (1) 

 the changes in the phosphates, in order to show to what extent the soluble 

 phosphate of lime becomes insoluble, (2) the extent to which the albumin was 

 precipitated and the casein changed in its characteristic property of coagulating 

 with reunin, and (3) the acidity of the milk.- 



For obtaining the milk serum, a clay filter prepared according to Soxhlet's 

 method was used. In order to note whether the serum remained constant in 

 composition during filtration, and for what length of time milk can be filtered 

 at temperatures of 5 to 8° C. (41 to 46.4° F.) without bringing about a change 

 in composition, some tests with skim milk were made. At the beginning of 



