22C) EXPERIMENT STATION RECORD. 



method of Gustavson. The author having adopted a number of modifications intro- 

 duced by various chemists, carries mil the chromic method as follows: 2.5 to 5 or 



more grams of the soil arc treated with a 5 to 1(1 per cent solution of phosphoric 

 acid, dried at UK! to 105° C, and then transferred to a flask of 250 cc. capacity by 

 the aid of a mixture of 30 cc. of concentrated sulphuric acid and L'(t cc. of water. 

 Instead of potassium bichromate crystallized chromic acid (CrO s ) is used to t lie 

 amount of 7 to 9 gm. 



It is quite necessary to regulate the oxidation. In Hi seconds is to 20 gas bubbles 

 should pass through the potash bulbs tilled with concentrated sulphuric acid for the 

 absorption of the water. The product of the oxidation and the water vapor pa- 

 first through a Classen cooling apparatus ami then, in order to retain the vapor of 

 hydrofluoric and hydrochloric acid, through a U containing a bright fine iron wire 

 spiral. The carbon dioxid is absorbed in the usual way. 



The results obtained by this method were somewhat lower than those obtained 

 by < iustavson's method. This difference is due, according to the author, to the fact 

 that there is in the soils ready-formed carbon dioxid which Gustavson does not 

 remove by treatment with phosphoric acid before the combustion. By using chromic 

 acid in place of potassium bichromate the author avoids some sources of error con- 

 nected with the formation of chrome alum in the latter case. — p. fireman. 



On the question of the acetic-acid extract of soils, IX N. I'm amsiinikov 

 (Zhur. Opuitn. Agron. [Jour. Expt. Landw.], 5 (1904)-, No. .'. j>/>. 197-200; abs. in 

 Chem. Centbl., 1904, II, No. 6, p. 554). — The author believes that the results obtained 

 by extracting soils with acetic acid does not furnish a reliahle means of judging of 

 their fertilizer requirements, Account must be taken of the insolubility of the 

 reverted phosphoric acid in the solvent. Moreover, the iron phosphate which is 

 insoluble in acetic acid furnishes a fairly assimilable source of phosphoric acid for 

 plants as Gedroitz has shown (E. 8. R., 15, p. 549) and the author has confirmed in 

 sand cultures with oats, millet, and lupines in 1900 and 1903. 



On the reaction of lard from cottonseed meal-fed hogs, with Halyhen's 

 reagent, E. Fulmer (lour. Anier. Cltem. Soc, 26 ( 1904), No. 7, pp. 887-851). — The 

 effect of cotton-seed oil upon the character of lard was studied. The minimum amount 

 consumed during the experimental period was l.S lbs. per 100 lbs. of weight, and 

 the maximum amount 75 lbs. Samples of fat were in every case taken from the 

 kidney, jowl, back, and intestines, and in many eases from the belly also. 



"All lard samples gave a distinct and, in some cases, a very strong coloration when 

 treated with Halphen's reagent. The coloration equivalent, expressed in percentages 

 of cotton-seed oil, ranged from 0.4 to 15 per cent. In general, the greatest degree of 

 coloration was found in kidney fat lard, and the least in intestinal fat lard. . . . 



"If the degree of coloration with Halphen's reagent is to be expressed in terms of 

 percentage of cotton-seed oil, the kind of oil used for comparison, and the conditions 

 under which the comparison is made should be stated, because different oils respond 

 with unequal intensity, and the depth of color increases after cooling. When the 

 color-producing substance is once deposited in the fat of hogs, it is exceedingly 

 persistent. . . . 



"While the evidence is somewhat conflicting we are rather unwillingly led to 

 the conclusion that probably the color-prod ucing principles are separated from the 

 cotton-seed oil by metabolic processes, and that the effects of metabolism are so pro- 

 found that its final products, if they find their way into the fat, do not modify it 

 in any important degree." 



Identification of boric acid in meat, A. Reinsch (Ber. Untersuch . , Altona, 1903, 

 pp. 10, 11; abs. in Ztschr. Untersuch. Nahr. u. Genussmtt., 7 (1904), No. 9, \i. 555). 



Concerning a new method of estimating sugar in chocolate, A. Steinm \nn 

 {Ztschr. Oeffentl. Chem.., 9 (1903), pp. 239-249, 261-269; abs. in Ztschr. Untersuch. Nahr. 

 u. Genussmtt., 7 (1904), No. 9, pp. 560-562). 



