816 EXPERIMENT STATION RECORD. 



any way the io<lin number of the milk fat. Linseed oil was saponified with sodium 

 hydroxid, and the resulting soap combined with bread was given to goats in quanti- 

 ties of 10 to 35 gm. daily. In one instance the iodin number of the milk fat was 

 increased from about 32 to over 41 and in another instance from 35 to 55. There was 

 no increase in the free acids. Saponified stearic acid fed to a goat caused a decrease 

 in the iodin number from 45 to 28. Spermaceti was also used in experiments with 

 goats. 



The author concludes from his experiments with animals (see also E. S. R. , 16, 

 p. 2!)!)) that food fat in a considerable quantity and without changes in chemical 

 properties passes over into the milk fat, part directly and part through the deposits 

 of fat in the animal body, and that the milk glands are capable of utilizing soaps in 

 the formation of milk fat. Linseed oil and hemp oil given to 3 nursing women 

 caused considerable variations in the iodin numbers of the milk fat. A bibliography 

 is appended. 



Iron content of human milk, Cameree anil Soldner (Ztschr. Biol., 46 (1905), 

 No. ■•', /-. 371). — From 845 cc. of human milk 2.876 gm. of ash was obtained, of which 

 1.97 mg. was Fe z 3 . In a second instance 3.765 gm. of ash containing 1.89 mg. of 

 Fe 2 3 was obtained from 1.5 liters of milk. In the first ease, therefore, 100 cc. of 

 milk contained 0.21 mg. of Fe 2 ;j , and in the second 0.13 mg. ; and 100 gm. of ash 

 contained in the two instances, respectively, 66.4 and 50.2 mg. of the ferric oxid. 



Disappearance of bacteria artificially introduced into cows' udders, H. L. 

 Russell and E. G. Hastings ( Wisconsin Sta. Rpl. 1904, pp. 164-168). — The experi- 

 ments were made with Bacillus acidi lactici, an acid-producing liquefying bacillus iso- 

 lated from Cheddar cheese, B. prodigiosus, and a yellow liquefying coccus isolated 

 from foremilk. Agar cultures of these organisms were transferred to distilled water 

 or normal salt solutions and introduced into the udder through a milking tube. 



The results for the experiment, which were made with several animals at different 

 times, are tabulated and furnish, according to the authors, no evidence of the growth 

 of any of the introduced species within the udder. In nearly every instance the 

 milk became abnormal and occasionally the udder became inflamed and tense, show- 

 ing the production of a temporary garget. 



Can fresh sterile milk be obtained? V. Willem and A. Minne (Rev. Gm. Lait, 

 4 (1904), No. 6, pp. 121-130; 4 (1905), No. 7, pp. 145-154).— In 4 series of experi- 

 ments with 3 cows, 38 samples of milk were obtained with great precautions to avoid 

 contamination in milking. Bacteriological examinations of these samples showed 

 the presence of 17 different forms of micro-organisms all of which were believed to 

 have gained access to the milk from other sources than the interior of the udder with 

 the exception of the streptococcus of mammitis. 



So far as these experiments go, the authors believe that they indicate that the 

 milk in the healthy udder exists in a sterile condition, and becomes contaminated 

 in milking in the teat and at the orifice of the duct. It is noted that these results 

 support the earlier views advanced by Pasteur, Duclaux, and others rather than agree 

 with the recent investigations of Ward, Boekhout and de Vries, von Freudenreich, 

 and others, but it is distinctly stated that they are published only as a preliminary 

 note on investigations which are being continued. References are given to the 

 recent literature of this subject. 



Effect of short periods of exposure to heat on tubercle bacilli in milk, 

 H. L. Russell and E. G. Hastings ( Wisconsin Sta. Rpt. 1904, pp. 178-192).— Milk 

 was inoculated with cultures of tubercle bacilli of human and bovine origin and 

 subjected in sealed tubes to different degrees of heat for varying lengths of time, the 

 main object, however, being to determine the time required to destroy the bacilli at 

 160° F. with a view to applying the results to the continuous pasteurization of milk. 



Five series of experiments are detailed, in each of which the virulence of the milk 

 was determined by intraperitoneal inoculation of guinea pigs. The conclusion is 



