684 



grains lactic acid per kilogram live weight) was accompanied by an 

 increased storage of albuminoid materials in the body, assumed by the 

 author to be due to its decreasing the nitrogen metabolism of the boily. 



Increasing the lactic acid to 120 and 180 grams per day did not 

 increase the amount of nitrogen stored in the body. 



To study the action of acetic acid the same sheep was fed the same 

 basal ration as before, to which GO grams of acetic acid in the form of 

 sodium acetate were added daily. After this the feeding was continued 

 with the basal ration. The average daily excretion of nitrogen in the 

 urine was 16.54 grams previous to the feeding of acetic acid, 17.04 grams 

 during the acid feeding, and 10.50 grams after. 



The effects of the addition of like quantities of lactic acid in the 

 form of calcium lactate, and acetic acid in the form of sodium acetate 

 to the same normal ration were very different. Wliile the former (lac- 

 tic acid) diminished the nitrogen metabolism and increased the storage 

 of nitrogen, the latter was diuretic in its action and increased the nitro- 

 gen metabolism of the body. 



The determination of free fatty acids in feeding stuffs, G. Loges and C. 

 Claessen {Landiv. Versuchs-Stationen, 38, ^>. 314-316). — This is a com- 

 parison of four methods of determining the free fatty acids in feeding 

 stuffs, on 12 samples of rice meal, cotton-seed meal, wheat bran, rye bran, 

 and pea-nut, rape, linseed, sesame, cocoa, palm nut, hemp, and sunflower 

 cakes. 



The methods of treatment were as follows : 



(1) Saniole dried for 3 hours, extracted with ether, the ether extract dried at 100° C. 

 for 2 hours, the residue dissolved in 25 c. c. ether, 25 c. c. alcohol added, aud the solu- 

 tion titrated with tenth-normal soda solution. 



(2) Sample dried for 3 hours, extracted with ether, 25 c. c. of alcohol added to the 

 ether extract, without previous drying, and the solution titrated with soda soluiioa 

 as above. 



(3) Sample extracted without previous drying, and the ether extract treated as in 2. 



(4) Sample digested with ether at ordinary temperature (10 grams substance and 

 100 c. c. ether) for 3 hours with frequent shaking, and an aliquot part of the filtrate 

 treated as in 2. 



Alcoholic soda solution and phenolphthalein were used for all the 

 titrations, and the results were calculated for oleic acid. 



The tables of results show: (a) Method No. 1 in almost all cases 

 gave too low results; in extreme cases it indicated only about one half 

 of the acid really present. (&) In some materials the low results seemed 

 to be due to the volatilization of part of the acids by drying the sub- 

 stance previous to extraction with ether (indicated by comparison of 

 results by 2 aud 3). In other materials no loss seemed to be traceable to 

 this cause, but loss seemed to come from the volatilization of the acids 

 in drying the ether extract (indicated by comparing results by methods 

 1 and 2). This variation in the behavior of different materials is 

 believed to be due to differences in their cellular constitution, one sub- 

 stance allowing the acids to escape from its cells in drying much more 

 readily than another, (c) The results by methods 3 and 4 agreed quite 



