176 EXPERIMENT STATION RECORD. 



uoue complies with the standard. ^Yhile admitting tliat the hacterial counts of 

 the certified milks were rather disappointing, the author believes that these milks 

 are probably among the best produced in this country. With the present equip- 

 ment of railroads, a standard of 10.000 bacteria jier cubic centimeter is be- 

 lieved to be too hard to attain. Suggestions are made for the improvement of 

 present conditions. 



On the influence of high carbon dioxid pressure on the bacteria in water 

 and milk, W. Hoffmann {Arch. Hyg., 57 {1906), No. J,, pp. 319-J,00, fig. 1).— 

 Subjecting water to a carbon-dioxid pressure of 50 atmospheres for 24 hours pre- 

 vented the development of bacteria. The same was also true of water inocu- 

 lated with typhoid, cholera, and dysentery organisms and subjected to the same 

 pressure for 3 hours. 



Milk treated in the same manner for 24 hours at 56° showed a precipitation 

 of the casein. The bacteria, however, were capable of growth after being sub- 

 jected to these conditions. Milk obt.-iined under hygienic ])recautions and sub- 

 jected to carbon-dioxid pressure remained sweet for 24 to 48 hours longer than 

 the same milk not subjected to pressure. In diluted serum agglutinins were not 

 Injured by the influence of moderate pressure for 48 hours, though bacterial 

 development was checked or prevented. 



The preservation of milk, especially with, hydrogen peroxid, A. Babes 

 {Ahs. in Rev. G6n. Lait, 5 {1906). No. 16, pp. 381, 3S2).— The author argues 

 that hydrogen peroxides superior to formaldehyde as a means of preserving 

 milk to be used for the purpose of immunization against tubei'culosis according 

 to the method of von Behring. 



Whole milk, skim milk, buttermilk, and cream, 1906 {Lah. IiiJaiid Rev. 

 Dept. [Canada'] Bui. 121, pp. J/S). — Of 319 samples of whole milk analyzed, 45 

 were pronounced adulterated and 85 doubtful. This was more unfavorable 

 than the results ol)tained in previous years. Twenty-nine samples of ci'eam 

 examined showed percentages of fat ranging from 12.G3 to 33.51. The author 

 believes that the following standard should be established in Canada : Whip- 

 ping cream not less than 25 per cent of fat, and table cream not less than 17.5 

 per cent. 



Further bacteriological investigations of the butter of Stuttgart, A. Reitz 

 iCentbl. Bakt. [etc.], 2. Ahf., 16 {1906), Nos. 22-23, P2). 119-133; 25, pp. 116- 

 191,, pi. 1, dgm. J).— The earlier investigations (E. S. R., 17, p. 1109) were con- 

 ducted for the purpose of determining the presence of tubercle bacilli in butter. 

 In the present investigations 30 samples of butter were examined for the pres- 

 ence of typhoid and diphtheria bacilli, negative results being obtained. 



Typhoid bacilli added artificially to butter made from sweet cream were 

 found alive at the end of 10 days, but not after 15 days. In butter made from 

 sour cream the typhoid bacilli were alive after 7 days, but not at the end of 10 

 days. The total number of bacteria varied between 9,000,000 and 40,000,000 

 per gram. It is believed that insufficient attention was paid to pasteurization. 

 For the determination of the total number of bacteria, gelatin was preferred 

 to agar. During the first few days the bacterial content of the butter decreased, 

 after which it increased rapidly for 2 to 3 weeks, when it was 2 to 3 times as 

 great as at the beginning. The numbers then decreased. The species of bac- 

 teria found which were considered of si)ecial importance were Bacterium coli 

 comynune. Streptococcus ptiogeiws, B. prodigiosum. species of Actinomyces and 

 Saccharomyces, and molds. The last 3 groups were considered as having a 

 marked influence on the rancidity of the butter. 



An extended liibliography of this subject is appended to the article. 



Investigation of salt, A. Hesse {Milrlnr. Zeiithl. 2 {1906), No. 1, pp. 295- 

 302).— Analyses of U2 samples of dairy salt representing ttie different brands in 



