448 BACTERIOLOGY. 



1854 onwards, developed the view that a dis- 

 tinction must be made between those disease 

 germs which develop endogenously only in sick 

 men and those which reproduce themselves 

 ectogenously outside of the human body. The 

 experiments begun in 1857 by Semmelweiss 

 upon the prevention of childbed fever by 

 keeping away decomposable substances, and 

 those by Lemaire in 1860, who proved that 

 carbolic acid annulled the action only of living 

 germs and not of enzymes, were recognized to 

 be of great importance. 



But direct discoveries also were not lacking. 

 Pollenderin 1849 an ^ Davaine and Rayer in 

 1850 discovered the anthrax bacteria. The 

 etiological significance of the germs was 

 clearly pointed out by Davaine about 1863, 

 and in 1877 Koch, by the discovery of the 

 spores, brought the question to a satisfactory 

 conclusion, as in earlier times Audouin had 

 rendered complete the discovery of Bassi. A 

 similar discovery was made by Pasteur in 1865 

 in another disease of silkworms, pebrine, 

 which he likewise brought to a satisfactory 

 conclusion by the demonstration of spores. 

 Obermeier in 1873 discovered the Spirochaete 

 of relapsing fever. Von Recklinghausen, 

 Waldeyer, Klebs and Weigert had already 

 found bacteria in the tissues in various dis- 



