45 
From these results Bang concludes that while heating at 60° for 
fifteen minutes does not prevent peritoneal infection it weakens the 
bacteria so that they are innocuous by way of the alimentary tract. 
Concerning his work vith cultures, it is interesting to note that 
glycerin-bouillon tubes sowed vdth particles of growth from a young 
culture failed to develop any growth after exposure to 60° and 65° 
for five minutes, although unheated controls grew well. 
Bang did not report results at 60° for twenty minutes. 
Tjaden,® 1903, obtained very high thermal death points for the 
tubercle bacillus and concludes that 85° for one to two minutes is 
necessary to kill that organism. Bang attributes this high resistance 
to the coagula winch formed during some of the experiments. 
Rullmann,^ 1903, in a preliminary note, says that he can not agree 
\vith those observers who state that 60° for fifteen or twenty minutes 
kills the tubercle bacilli in milk. He found that milk infected vdth 
tuberculous sputum exposed to 65° for half an hour ‘SHth all pre- 
cautions” still caused tuberculosis when injected intraperitoneally 
into guinea pigs. He promises a full report, which, however, we 
have not been able to obtain. 
Barthel and Stenstrom,*' 1904, continue their experiments relative 
to the effect of the reaction of milk upon the resistance to heat of the 
contained tubercle bacilli. The^^ dhfided into two portions some 
tuberculous milk; one portion was rendered abnormally acid, 
another neutral in reaction. The neutral milk vfithstood 90° vdthout 
coagulation; the acid milk coagulated at 60°. 
Results vdth 80°: One minute exposure killed in uncoagulated 
milk, but not in coagulated, i. e., acid milk. 
At 85°: Momentary exposure failed to kill in either. One minute 
exposure killed in uncoagulated but not in coagulated milk. 
While these experiments are very limited in scope, they at least 
suggest a source of error in tbe work of those who used the secretion 
of tubercular udders in their experiments. Such material is prone to 
be abnormal in reaction, and protective clots may have been formed. 
Sydney Phillips, 1904, mentions merely that the results obtained 
by Russell and Hastings^ were confirmed by Macfadyean of the 
Lister Institute. 
« Tjaden: Abtodtung der pathogenen Keime in der Molkereimilch durch Erhitzung 
ohne Schadigung der Milch und Milchproducte. Dent. Med. Woch., 1903, p. 976. 
& Rullman : Eeber die Abtodtung von Tuberkelbacillen in erhitzer Milch. Miinch. 
med. Woch., 1903, vol. 31, p. 1342. 
c Barthel, Chr., and Stenstrom, 0. : Weitere Beitrage zur Frage des Einflusses hoher 
Temperaturen auf Tuberkelbacillen in der Milch. Cent. f. Bakt. , vol. 37, 1904, p. 459. 
d Phillips, Sydney : The milk supply of a hospital ; American method of sterilization. 
The Hospital, July 16, 1904. 
« Russell and Hastings. University of Wisconsin Agricultural Experiment Station, 
^ 17th Ann. Rep., 1900. 
