10 EXPEKIMENT STATION EECOED. 



mately deeinormal), is run in, amid shaking, until the solution is pink to 

 phenolphthalein. A final adjustment is made with deeinormal sodium hydrate 

 or suljihuric acid. To the solution thus prepared is added 2 cc. of a deeinormal 

 sulphurie solution, then made up to 150 ec., mixed thoroughly, filtered, and the 

 residual silver in 100 ce. of the filtrate determined according to the Volhard 

 method. The results obtained in the presence or absence of nitrates, calcium 

 salts, sulphuric acid, etc., were excellent. Chlorids, if present, must be allowed 

 for. 



The volumetric estimation of potash in organic liquids, W. A. Drushel 

 (Ztschr. Anorgan. Chem., 61 (J 909), A^o. 1, pp. tSl-l'iG; abs. in Bui. Soc. CJiim. 

 France, 4- set\, 8 {1910), No. 4, P- 27S). — The oxidizing material was a mixture 

 consisting of 9 parts of nitric acid and 1 part of sulphuric acid. When protein 

 is present nitric acid or bromin is used for the oxidation. In the latter in- 

 stance, however, the acid is driven off and the residue taken up with hydro- 

 chloric acid and then heated again. For estimating potash the residue is taken 

 up with a few drops of acetic acid in a little water. To this is added an excess 

 of sodium cobalti-nitrite solution, and the whole evaporated to dryness. On 

 cooling a little cold water is added, filtered through an asbestos filter, and the 

 precipitate washed with a half-saturated solution of sodium ehlorid. The pre- 

 cipitate is then oxidized with potassium permanganate and the excess of 

 permanganate determined with deeinormal oxalic acid solution. 



Notes on the analysis of edestin and zein, T. B. Osborne and L. M. Liddle 

 (Amer. Jour. Physiol, 26 {1910), No. 4, pp. 295-304) .—The latest results ob- 

 tained in the analysis of edestin and zein indicate that considerable losses of 

 amino acids, especially alanin, must have occurred in former analyses of these 

 proteids. The authors also show that very satisfactory esterifications can be 

 obtained with Phelps and Phelps' method ° (used in the malonic acid work by 

 Phelps and Tillotson*) with proteins which yield small or large amounts of 

 basic amino acids. Contrary to Abderhalden's findings, they were not able to 

 isolate any oxyprolin from the decomposition products of edestin. 



The hydrolytic products of zein reported, which are believed to repi'eseiit the 

 actual proportions more accurately than any separate analyses, are as follows : 

 Glycocoll, none ; alanin, 9.79 ; valin, 1.88 ; leucin, 19.55 ; prolin. 9.04 ; phenyla- 

 lanin, 6.55 ; aspartic acid, 1.71 ; glutaminic acid, 26.17 ; serin, 1.02 ; tyrosin, 3.55 ; 

 arginin, 1.55 ; histidin, 0.82 ; lysin, none ; tryptophan, none ; ammonia, 3.64 ; and 

 carbohydrate, none ; making a total of 85.27 per cent. 



A consideration of the sources of loss in analyzing the products of pro- 

 tein hydrolysis, T. B. Osiorne and D. B. Jones (Amer. Jour. Pln/.'iioL, 26 

 {1910), No. 4, pp. 305-328). — The authors claim that many of the causes of loss 

 in analyzing the products of a protein hydrolysis are due to the present methods 

 of analysis. With this in mind, they have analyzed zein with a view to obtain- 

 ing the highest possible results and to gain a knowledge of those products of 

 hydrolysis which can not be separated into definite substances, and. further, for 

 purposes of comparison have analyzed by the same method a mixture of pure 

 amino acids in the same proportion as found in the protein analyzed. 



Abovit the individuality of cellase and emulsin, G. Bertkand and A. Comp- 

 TON {Compt. Rend. Acad. 8ci. [Paris'], 151 {1910), No. 5, pp. 402-404) .—The 

 results show that cellase and emulsin are present together, but in variable pro- 

 portions. This indicates that they are individual enzyms (see E. S. R., 23, p. 

 306). 



"Amer. Jour. Sci., 4. ser., 24 (1907), p. 194. 

 6 Amer. Jour. Sci., 4. ser., 26 (1908), p. 243. 



