483 
the species gaining access to the milk find the condition so different 
to their natural habitat that they are not able to multiply and there- 
fore they drop out very soon. On the other hand, common lactic- 
acid organisms multiply more or less rapidly and continuously from 
the start. He believes that the reduction in the number of bacteria 
during the first few hours is not the result of any germicidal condi- 
tion or property possessed by the milk, but simply the natural drop- 
ping out of those species which do not find the milk a suitable 
medium in which to develop. 
Behring, 0 1904, in his recent publications claims that milk has 
similar bactericidal property to that possessed by the blood. Fur- 
ther, that these bactericidal substances are rendered inactive at 60° 
C. for one hour or 50° C. in vacuo. He believes that heating milk to 
60° C. for sixty minutes appreciably weakens the immune bodies 
contained in it, and that the great mortality of infants in large 
cities has a direct relation to the use of cooked milk. He believes 
that the important point in infant feeding is to use milk in which 
the native antibodies are intact. He uses this as one of his argu- 
ments in advocating the use of formaldehyde to preserve milk. 
Friedel, Kutscher, and Meinicke, 5 1904, working under Kolle’s 
direction, in Koch’s Institute for Infectious Diseases, at Berlin, found 
as a result of numerous experiments that fresh raw milk contains 
bactericidal properties, similar to those of fresh blood serum, against 
the cholera vibrio. But no such property was found as far as the 
typhoid, paratyphoid, and dysentery bacilli, the organism of meat- 
poisoning, and B. coli are concerned. 
They found that fresh raw milk has a feeble property of restrain- 
ing the growth of the dysentery bacillus. This property is not de- 
stroyed by heating the milk to 60° C. for one hour, but is destroyed 
above 70° C. These investigators believed that this property of milk 
in question is a restraining action and not a bactericidal one, espe- 
cially in view of their dilution experiments. 
They found that the bactericidal property of milk, as far as the 
cholera organism is concerned, is weakened by heating the milk to 
60° C. and by the addition of hydrochloric acid, pepsin, and sputum. 
Knox and Schorer c find that neither raw nor pasteurized milk 
seems to exert any definite deterrent action upon the growth of the 
0 Behring. E. : Sauglingsmilch und Sauglingsterblichkeit. Therapie die Gegen- 
wart, n. s., vol. 4, 1904, p. 1-10. 
6 Untersuchungen iiber die bakteriziden und entwickelungscbemmenden TVirk- 
ungen der roben und der auf verschiedene Temperaturen erwarmten Milch 
gegen iiber den oben gennanten Bakterien. Kliniscbe Jabrbucb, vol. 13, 1904-5, 
p. 328. 
c Knox, J. H. Mason, and Schorer. Edwin H. : A study of hospital and dispen- 
sary milk in warm weather, with special reference to pasteurization. Arch, of 
Pediatrics, July, 1907. 
