He also noted that by the use of cultures on plates there was first 
a diminution in the number of bacteria in milk. He further found 
that the brief heating of milk did not always destroy its bactericidal 
properties, but that prolonged heating at 70° C. is sufficient to 
destroy this action. 
Uffelmann a observed the multiplication of cholera vibrios during 
the first twelve to sixteen hours in raw milk to be less than in the 
controls with cooked milk. 
Weigmann and Zirn * * 6 also investigated the question of cholera 
vibrios in raw milk and found a diminution in the first four hours, 
but not in cooked milk. They believe that the presence of acid 
causes the killing of the vibrios. 
A few years later, 1894, Hesse c confirmed the pioneer work of 
Fokker and stated most positive^ that cholera and typhoid are 
both killed by fresh milk and concludes from his studies as follows: 
The killing of the organisms begins the moment the cholera bacilli are added to 
the milk. This is complete, almost without exception, at room temperature (15°-20° 
C.) within twelve hours; at incubator temperature within six to eight hours. The 
destruction of the organisms is independent of the acid content of the milk, and 
independent of the milk organisms and their metabolic products. It is more prob- 
ably to be looked upon as a vital function of the living milk, which is immediately 
lost upon heating to 100° C. 
He, therefore, recommended the use of raw milk as a therapeutic 
measure in cholera. 
Basenau, d 1895, disagrees with Hesse in that he could not confirm, 
the destruction of cholera vibrios in raw milk, but found, on the con- 
trary, that these organisms multiply vigorously from the start. He 
also experimented with B. morbijicans bovis (enteritidis group) with 
the same result. He drew his milk from a healthy cow under spe- 
cial antiseptic precautions, but could not demonstrate definite bacte- 
ricidal substances in the milk. At most Basenau believes that there 
is only a temporary restraining power, and he found that a similar 
restraining action was present when bacteria were transplanted into 
nutrient bouillon, and therefore this property is not specific for milk. 
Heim e agrees with this view and adds to the list of organisms which 
are not affected typhoid and tubercle bacilli. 
« Uffelmann, J. : Beitrage zur Biologie des Cholerabacillus. Berl. klin. Woch., 
vol. 29, 1892, p. 1209. 
& Wiegmann, H., and Zirn, Gg.: Ueber das Verhalten der Cholerabakterien in 
Milch und Molkereiprodukten. 
c Hesse, Walter: Ueber die Beziehungen zwischen Kuhmilch und Cholerabacillen. 
Zeit. f. Hyg., vol. 17, 1894, p. 238. 
<2 Basenau, Fritz: Ueber die Ausscheidung von Bacterien durch die thatige Milch 
druse und liber die sogen. bactericiden Eigenschaften der Milch. Arch. f. Hvg., vol. 
23, 1894, p. 44. 
e Heim: Arb. Kais. Gesundhamte. , vol. 4, p. 294. 
