1084 EXPERIMENT STATION RECORD. 



cent of fat in the first portion of a milking and IS per cent in the last jwrtion were 

 repeatedly olwerved. 



Portions of the four different parts of the niilkings mentioned were coUeeted sei)a- 

 rately until enough cream was secured tomake churnings, and the l)nttcrfat obtained 

 in each case was examined by the Reichert and Iluebl methods, and for refractive 

 index. The Reichert numbers found did not differ materially, and but small differ- 

 ences were observed in the iodin absorption numbers and the refractive indexes 

 for the 4 samples, the former being 38.4, 39.7, 39.2, and 38.2 forsamples 1 to4, respec- 

 tively, and the latter 52.6, 53, 53, and 52.5. — f. w. woll. 



The dairy maid's book, N. Oedegaard (BudeHjogen. C'hrisiiania, Xortray, 190^, 

 2. I'd., pp. 00). — A prize essay on the feeding and handling of dairy stock, written 

 especially for dairy maids {Budeier). — f. w. woll. 



Successful dairying, J. Klein ( Erfolgreiche MUchivirtschaft. Berlin: Pmd Parey, 

 1903, pp. 3.->S, Juj.^. 95). 



The liberation of volatile sulphid from milk on heating, L. F. Rettoer 

 {Amer. Jour. Physiol., 6 {1902), No. 6, pp. 450-457).— The author finds, in confirma- 

 tion of the observations of Niemann and Oppenheimer, that sulphid is given off on 

 heating normal milk above 85° C. This is believed to be in all probability hydrogen 

 sulphid, and to be due to the partial decomposition of the milk proteids. The 

 amount of sulphur liberated was very small, l)ut was sufficient to be easily recognized 

 by the blackening of lead acetate ])aper and lead acetate cotton as well as of the 

 decoloration of dilute potassium permanganate solution. As might be expected 

 from the low content of proteids, pure milk yielded much less of the volatile sulphid 

 than whole milk, while skim milk when perfectly fresh gave off more sulphid. 

 Alkalis and alkaline-reacting phosphates were found to facilitate this decomposition 

 of the proteids, while acids and acid-reacting phosphates retarded it. Hence the 

 amount of sulphid liberated depends largely on the reaction of the milk. 



' ' What part this liberation of sulphid may take in rendering milk injurious is a 

 question of practical significance. The reaction is in itself conclusive evidence that 

 the milk suffers a change in composition. The important question arises: 'Does 

 sterilization and pasteurization render it injurious for prolonged use?' There is 

 some evidence that scurvy in infants results from the use of milk sterilized l)y boil- 

 ing. May this result be connected with alterations in the proteids, permitting the 

 liberation of volatile sul]>hid?" 



On the thermal death point of tubercle bacilli, B. Bang {Mdlkeritid., 14 

 {1901), No. 42, pp. 677-679). — Experiments were made with tuberculous milk heated 

 in a closed metal vessel, through the cover of which a thermometer was inserted. 

 The apparatus was kept in a deep water bath of constant temperature and shaken 

 steadily so as to insure a uniform heating of all particles of milk. Tuberculous milk 

 heated to 60° C. for 1 minute or less caused pnjnounced tul)erculosis by inoculation 

 into the abdominal cavity of rabbits. Milk kept at 60° for 5 minutes also caused 

 tuberculosis, but to a less extent. Heating for 15 minutes reduced the effect still 

 more, only half the number of animals becondng tuberculous. Milk heated to 65° 

 for a moment caused a rather slight, but still recognizable tuberculosis. On heating 

 at 65° for 5 minutes the bacilli were killed. The same result followed heating for a 

 moment to 70, 75, 80, and 85°. Feeding experiments with milk heated to 60° for 2 

 minutes gave negative results. 



In case of continuous pasteurization the author considers 80° the lowest safe tem- 

 perature for destroying tubercle bacilli, and believes that the Danish pasteurization 

 law maj' be modified without danger to allow j)asteurization at this tcmi)erature in 

 creameries, the Storch color test (E. S. R., 10, j). 384) being used to ascertain whether 

 the skim milk has actually been exposed to this temperature. — f. w. woll. 



Report of the professor of dairying, H. H. Dean {Ontario Ayr. Col. and E.vpt. 

 Farm RpA. 1901, pp. 44-55).- — Experiments in cheese and butter making are reported 

 and a record is given of the dairy herd for the year ended November 30, 1901. 



