7 



MALIGNANT PUSTULE. 



into the general mass of the blood. But if this had 

 accidentally happened, they would have been destroyed 

 instead of multiplying, if the blood was in a healthy 

 state. In cases in which these organisms have been 

 discovered actively multiplying in the blood, that fluid 

 must have already undergone serious changes, which 

 had rendered it unfit for the nutrition of the body. 



I cannot agree with those who consider that we 

 have evidence in favour of the view that the bacteria 

 are really the active agents in cases in which the 

 blood has been shown to exhibit the properties of a 

 specific contagious virus. The disease called malignant 

 pustule has been attributed by Davaine (Comptes 

 Rendus, 1864) to the presence of bacteria in the 

 blood, but this observer does not prove that the 

 bacteria were the poisonous agents, and many cir- 

 cumstances render it probable that other matters 

 suspended in the blood constituted the real virus, 

 while the vegetable organisms were but harmless con- 

 comitants. Polli, Tigri, and many others, have 

 attributed typhoid fever and allied diseases to bac- 

 teria in the blood acting after the manner of ferments, 

 but the objections raised to the fermentation theory 

 have not yet been disposed of by those who advocate 

 this doctrine. Indeed, many authorities who have 

 attributed various phenomena to fermentation, and 

 have spoken of the fermentation theory, have not 

 explained what they mean by the terms they employ, 

 and appear to have very vague, notions concerning the 



