702 EXPERIMENT STATION EECORD, 



serves as an index (gross though it bo, witli our lu'osent very limited linowl- 

 edge) of those pliysico-clieniical properties whicli serve directly or indirectly 

 tt) differentiate genera, species, and individuals. In otlici' wfnds, vit;il peculiar- 

 ities may l)e resolved to a physico-clu'mlcal basis." 



On the biochemistry of nucleic acids, P. A. Levenk {Jour. Amcr. Chem. Soc, 

 .i.^ ( I'.ilO), No. 2, PI). 231-2^0). — In this pai)er the author presents a summary 

 and digest of data on the elementary composition of nucleic acids, their consti- 

 tution, and I'elaled questions. 



The biochemical role of bacteria, A. Horowitz-Wl.vssowa (Arch. Sci. liUA. 

 [tif. I'ctcrsb.], J.J (lOJO), No. I, pp. .'iO-')S). — Experiments are reported and dis- 

 cussed on the bacterial clesivage of protein. 



A critical study of the natural changes occurring- in fats and oils, J. S. 

 Hepburn {Jour. Franlclin Inni., 16S (lOO'-J). Vo.s-. 5, pp. ,i65-S8Ji; 6, pp. .'i2J-Ji5G; 

 169 {1910), So. ], pp. 23-5^). — This is a review of the various researches which 

 have been made in regard to the natural changes occurring in oils and fats. 



Action of nitric acid on starch, A. G. Doroshevski, A. V. Rakovski, and 

 A. Y. Bardte iZhur. Russ. Fiz. Khim. OJjshch., Chast Khim., J,0 {190S), No. 5, 

 2)t. 1, pp. 932-9JtO, fig. 1; nbs. in Bui. Soc. Chun. France, Jf. ser., 8 {1910), No. 2, 

 p. 89). — Studies were made in regard to the inversion of starch by 8, 6, and 14 

 per cent strengths of nitric acid, and from the results it is evident that the reac- 

 tion is increased in the same ratio as the concentration. The studies were made 

 with starches from different sources, and which the author divides into 2 groups, 

 group 1 containing the starches of potato, and the Bermuda and St. Vincent 

 arrowroot, and group 2 the starches of rice and wheat. 



Vicianose, G. Bertrand and G. Weisweiller {Compt. Rend. Acad. Set. 

 [Paris], 150 {1910), No. 3, pp. 180-182). — This is a new biose reducing sugar 

 obtained by acting upon vicianin with a diastase obtained from the seeds of 

 Vicia angusiifolia. It is the first biose prepared by diastatic hj-drolysis of a 

 glucosid. See also a previous note (E. S. R., 19, p. 129.). 



Investigations in regard to rennet action, Hoft {Arh. Vers. Stat. Mollao. 

 Kiel. 1909, No. 6, pp. 20-25; ahs. in GentU. Balct. [etc.], 2. AM., 2Jt {1909), No. 

 16-17, p. '/GO). — It was found that spontaneously and artificially acidified milks 

 have about the same coagulation time. Neither the reduction of acidity 

 to a small amount with the aid of potassium hydrate nor acidifying to a 

 medium strong degree had any marked influence on the coagulation time. For 

 whole milk and skim milk of. the same origin it was shown that on the average 

 the skim milk with a small degree of acidity had only a slightly slower coagu- 

 lation time than the whole milk. It is recommended in testing milks in this 

 regard to bring the different milks to the same degree of acidity. 



Differentiation of rennet coagulum from that produced by acid, Hoft {Arb. 

 Vers. Stat. Mollcw. Kiel, 1909, No. 6, pp. 12-19; abs. in Centbl. Bakt. [etc.], 2. 

 AM., 2.'f {1909), No. 16-17, p. //GO).— Rennet coagulum can be easily differen- 

 tiated from acid coagulum by comparing the ash content of the fat-free dry 

 substance. The rennet coagulum yields 8 to 10 per cent of ash, while that 

 from the acid has only from 4 to 6 per cent. Further, the calcium content of 

 the rennet coagulum is about 3 per cent, while that obtained from the fat-free 

 dry substance of the acid coagulum is only about 1 per cent. 



If the coagulation of milk is brought about by the combined action of acid 

 and rennet the coagulum shows evidences of a transition between the acid and 

 rennet coagulum. The temperature, also, has possibly some influence on the 

 ultimate composition of the ash. Determining the degree of acidity of the two 

 coagulates furnishes no definite idea as to their origin, particularly where the 

 estimation is not carried out directly after coagulation. 



