112 EXPERIMENT STATION EECORD. 



A new decomposition product of gliadin, T. B. Osborne and S. H. Clapp 

 {Anier. Jour. Physiol, 18 (1907), No. 2, pp. 123-128, figs. 2). — From gliadin 

 hydrolyzed by boiling for a considerable time with 25 per cent sulphuric acid, 

 a crystalline substance of definite character was isolated, which on vigorous 

 liydrolysis gave prolin and plienylalanin. It seems probable that this substance 

 is a dipeptid. The yield was in the proportion of about 4 gm. from 1 kg. of 

 gliadin. 



The quantitative estimation of extractive and protein phosphorus, \V. 

 Koch (Jour. Biol. Client., 3 {1901), No. 2, pp. 159-16'i). — The method outlined 

 is especially apidicable to a study of brain tissue and similar materials and, 

 according to the author, can be generally used in the study of normal and itath- 

 ological material. 



Determination of dry matter in milk, (4. IIinard {Bui. Hoc. Vliim. France, 

 Jf. scr., 1-2 (1907), No. 10, pp. ')oS, 5.59). — In determining totxl solids in milk the 

 author has endeavored to avoid by the use of formaldehyde the progi'essive 

 chajiges which take place in the proteids during prolonged heating. The 

 method as tried ex])erimentally consisted in addi?ig 3 drops of formalin to 10 

 cc. of milk, coagulating the milk l)y means of 5 or drops of a l-j per cent solu- 

 tion of acetic acid, and evaporating at 95 to 100° C. Heating for 5 days made a 

 difference of only 0.12 per cent in the weight of the dry matter. 



A reaction of formaldehyde with naphthalene in the presence of sul- 

 phuric acid, H. DiTZ (Chcni. Ztg.. 31 (1907), No. 35, pp. //i5--}-^7).— In the 

 presence of naphthalene dissolved in sulphuric acid, formaldehyde in very small 

 quantities is said to give a brown coloration and in large quantities a bright blue 

 coloration. In applying this test to milk the casein is precipitated by dilute 

 sulphuric acid and the naphthalene sulphuric acid reagent is added to a small 

 quantity of the clear whey. 



On the determination of water in butter, H. Faber (Mwllccritid, 20 (1907), 

 No. 11, pp. 199-211). — Descriptions are given of the following methods of deter- 

 mining the water content of biitter in creameries : Gravimetric chemical analysis, 

 the Gray, the Gerber, and the Carroll method. The last method given, which 

 was invented by Professor Carroll in Dublin, in the author's opinion, bids fair to 

 prove the most satisfactory as a itreliminary approximate test. — f. w. woll. 



Note on the determination of volatile fatty acids in butters (Reichert 

 number), L. de Ko.mngh (CJicni. Nctrs. 95 (1907), No. ;2-'/77. p. 229). — A modi- 

 fication of the Reichert method is suggested for use when the (juantity of butter 

 is small and an early analysis is required. The process is as follows : 



" The butter is melted in a test tube placed in hot water, and 2.5 gm. of the 

 clear fat are saponified with 12.5 cc. of normal alcoholic caustic potash in a flask 

 fitted with a long vertical tube. When saponified 25 cc. of distilled water are 

 added, and the whole evaporated in a basin to pasty consistenc-y. The soap is 

 dissolved in warm water, made up to exactly 00 cc, and placed in the distilling 

 flask. Fifteen cc. of normal sulphuric acid ai"e then added, also some fragments 

 of clay pipe. The whole is then submitted to distillation and 50 cc. are collected. 

 The distillate is filtered into a 300 cc. flat-bottomed Jena flask and titrated with 

 N/10 sodium hydroxid, with phenolphthalein as indicator. The result may, 

 however, be too high, as during the evaporation of the soap a not inconsiderable 

 quantity of carbon dioxid may have been absorbed, and the N/10 soda used in 

 the titration, unless freshly made, may have become somewhat carbonated. 

 Therefore 0.5 cc. of N/10 hydrochloric acid is added and the carbon dioxid ex- 

 pelled by rapidly heating the liquid to boiling and then boiling gently for 8 

 minutes. The flask is now rapidly cooled and the titration continuetl; the liquid 

 should, of course, be colorless. From the total number of cubic centimeters of 

 N/10 soda used 0.5 cc. is theu deducted." 



