114 EXPERIMENT STATION RECORD. 



ficially mixed again, a second separation is not so difficult. It is also in harmony 

 with our general knowledge of the chemical condition of the living organism. 



"When the chemical equilibrium of such a system of proteids in loose combina- 

 tion is upset by the addition of a precipitant, only a partial separation is effected, 

 some of the soluble proteids going into the precipitate and some of the insoluble 

 remaining in the nitrate, the loose combination in these two cases being maintained. 

 It is only by extensive and exact methods such as I have described that we can hope 

 to effect the isolation of such bodies." 



Simple proteids and their cleavage by ferments, A. Kossel and Da kin 

 (Munchen. Med,. Wchnschr., 51 (1904), No. 13, p. 545; abs. in Hyg. Rundschau, 15 

 (1905), No. 9, pp. 451, 452).— -The simplest known proteid, according to the authors, 

 is salmin, which gives 5 cleavage products, namely, ct-pyrrolidin-carbonic acid, serin, 

 amino- valeric acid, urea, and diamino- valeric acid or ornithin. Data are given regard- 

 ing the cleavage products obtained by the action of erepsin on clupein, and the 

 structure of proteids is discussed. 



Investigations on the vegetable proteids, T. B. Osborne (Connecticut State 

 Sta. Rpt. 1904, pi- 5, pp. 457-459). — This is a brief summary of investigations which 

 have been or are to be published in full in the American Journal of Physiology. The 

 subjects investigated are as follows: The alcohol-soluble protein substances of wheat 

 flour, the separation and purification of protein substances, the solubility of globulin 

 in salt solutions, and the protein constituents of the castor-oil bean. 



Detection of cotton-seed oil in lard, L. M. Tolman ( U. S. Dept. Agr. Yearbook 

 1904, PP- 359-362, pis. 4). — The author points out the difficulty of detecting lard 

 adulterants and the failure of ordinary tests for cotton-seed oil, and describes Bomer's 

 test, which has been found successful in detecting cotton-seed oil in lard. This test 

 depends upon the fact that phytosterol is present in vegetable fats but not in animal 

 fats. While lard from hogs fed cotton-seed meal gave the usual color tests that 

 w r ould be given byproducts containing added cotton -seed oil, no phytosterol was 

 present. Phytosterol may be identified by the form of the crystals or by the melting 

 point of the acetate. 



Investigations on the Gottlieb method of determining fat in milk, M. Sieg- 

 feld and W. Rosenbaum (Mil clue. Zentbl., 1 (1905), No. 6, pp. 244-248). — Compara- 

 tive tests of the Adams, Gottlieb, and Gerber methods are reported. The results by 

 the 3 methods agreed closely on skim milk and whey. With buttermilk, however, 

 the results by the Adams method were usually about 0.1 per cent lower than by the 

 Gottlieb method. The substance insoluble in ether obtained in the Gottlieb method 

 while not identical with lecithin is believed to be derived from that substance by 

 oxidation during drying. 



Studies on the possible saponification of fat by concentrated ammonia in 

 the Gottlieb-Rose method, A. Burr ( Milchw. Zentbl, 1 ( 1905) , No. 6, pp. $48-250) .— 

 The results of the experiments reported indicate that ammonia does not cause a 

 saponification of the fat in the determination of fat in milk by the Gottlieb-Rose 

 method. 



The identification of artificial coloring matter in fat, H, Sprinkmever and 

 H. Wagner (Ztschr. Untersuch. Nahr. u. Genussmll , 9 (1905), No. 10, pp. 598, 599).— 

 In the method described 10 gm. of melted fat is shaken with 10 cc. of petroleum 

 ether. Fifteen cc. of glacial acetic acid is then added and the mixture thoroughly 

 shaken and allowed to stand. Added coloring matter is indicated by the yellow or 

 pink color of the lower layer of the liquid. 



A new automatic pipette, Greiner and Friedrichs (Ztschr. Angew. ("hem.. IS 

 (1905), No. 12, p. 465, Jigs. 2). 



Standard methods of sampling: A review with some suggestions, M. L. 

 Griffin (Jour. Soc. Chem. Indus., 24 (1905), No. 4.. pp. 183-185).— A review. 



