50 
Hesse,® 1900, obtained sterile milk directly from the cow by the 
use of special precautions in test tubes, and inoculated these tubes 
with cultures of typhoid, cholera, diphtheria, and plague. They 
were heated to 60° C. for fifteen to twenty nfinutes in a water bath 
and plated. The plates remained sterile. Controls gave a good 
growth. Xo record is given of the effect of lower temperatures or 
shorter times. The possible effects of the ‘^germicidal” power of the 
raw milk was not considered. 
Bassenge,^ 1903, made about fifty-two determinations of the effect 
of various temperatmes upon tvphoid in raw milk. He used large 
quantities of raw milk— one-half to 1^ liters — to which had been 
added a broth culture tube of typhoid. The work was done in iron, 
porcelain, and enamel-ware vessels, over gas and coal ffames of vary- 
ing intensity. The milk was raised from room temperature to the 
desired point. Bassenge foimd that when milk was raised to a 
temperature of 60° C. in from five to ten minutes and plates made on 
Conradi-Drigalski mediimi no typhoid was found. When, however, 
the milk was raised to 60° C. in three minutes, t^'phoid colonies were 
present. He does not indicate whether the degrees reported were top 
or bottom temperatures. His figiues varied slightly, depending upon 
the composition of the vessel in which the milk was heated. 
Friedel, Kutscher, andMeinicke,^ 1904, working in Koch’s laboratory 
under Kolle’s direction, found that the typhoid, paratyphoid, and en- 
teritidis group of bacilli have the same resistance to heat. They were 
all killed vdthout exception when the temperature of the milk reached 
59° C., provided ten minutes elapsed from the beginning of the heating 
until this temperature was reached. 
These experiments were made by previously heating 'one-half to 1 
liter of milk to 100° in an Erlenmeyer fiask and after this cooled 
inoculating it vdth 10 c. c. of a fresh twenty-four hour bouillon cul- 
ture. The flasks were then set m a large kettle of hot water and 
precautions taken to obtain an equable distribution of heat. It 
required ten minutes to heat this quantity of milk from 15° to 60° C. 
At intervals of one minute 5 c. c. were taken with a sterile pipette and 
added to 50 c. c. of bouillon, incubated twenty-fom hours, and then 
plated upon agar. 
A review of the literature upon the viability of the typhoid bacillus, 
with especial reference to its thermal death point, ’will be foimd in 
Hyg. Rundschau, vol. 14, 1904, p. 353, by Ina Rosquit, and Zeit. f. 
Hyg., vol. 20, 1895, p. 308, by Max Xeisser. 
« Hesse, W. : Ueber das Yerhalten pathogenen Mikroorganismen m pasteurisirter 
Milch. Zeit. f. Hyg., vol. 34, 1900, p. 346. 
b Bassenge, R. : Ueber das Yerhalten der T\*phusbazillen in der Milch und deren 
Produkten. Dent, med, YToch., vol. 29, 1903, p. 264. 
Friedel, Kutscher, and Meinicke: Die Y'iderstandiahigkeit der Erreger der 
wichtigsten Darmkrankheiten gegen Erwarmen auf verschiedene Temperaturen in 
Milch. Klin. Jahrb., vol. 13, 1904-5, p. 324. 
