48 



the micrococci cause the suppuration. Experimentally 

 there is direct evidence to the same effect. 



Pasteur saw, after cultivation of a micrococcus found 

 in ordinary water, that the injection of a few drops of 

 the previously harmless culture-fluid, now containing 

 myriads of micrococci, was invariably followed, in the 

 rabbit, by suppuration around the point of injection, the 

 pus and tissues containing numbers of the same organ- 

 isms. The intr a- jugular injection of the same fluid caused 

 multiple abscesses in the internal organs. He found 

 the same micrococcus in pus from cases of puerperal fever. 

 Klebs, Zahn, and Tiegel found that while the injection 

 of pus from a py?emic abscess or putrid fluid was followed 

 by local suppuration and multiple abscess formation in 

 the infected animal, the same pus or liquid, after nitra- 

 tion through clay cylinders whereby the bacteria were 

 separated from the liquid caused intense general infec- 

 tion, but no suppuration, even at the point of injection. 

 Koch observed also the constant association of a charac- 

 teristic micrococcus with infectious suppuration in the 

 rabbit after putrid inoculation. 



It appears, therefore, impossible to evade the conclu- 

 ion that suppuration can be and is induced by micro- 

 cocci. That this effect is induced by one or more specific 

 varieties of these organisms seems probable from these 

 researches of Klebs, Koch, and Pasteur ; that it is not 

 induced by all species is apparent from the fact that 

 colonies of micrococci are frequently present in the 

 human and other animals during various morbid pro- 

 cesses in which suppuration does not occur as in 

 erysipelas. As to the mode in which this influence is ex- 

 erted, there is no definite knowledge ; the assumption 

 that the deleterious effect results from changes in the 

 chemical constitution of the containing medium, as an 

 essential feature of the vital activity of these organisms, 

 is supported by analogy with the processes of fermenta- 

 tion and putrefaction, by the phenomena known to at- 

 tend the life of other bacteria, and by the direct observa- 

 tions of Koch and Pasteur. 



