THE MICKOBKS OF HUMAN DISEASES. 205 



Ferran's laboratory, that the instruments and methods 

 in use there were primitive and insufficient. 



Until these facts have been confirmed by other 

 observers, it seems prudent to regard P. Ferrani and 

 B. kortima as two absolutely distinct microbes. It 

 does not follow that the culture liquids employed by 

 Ferran did not contain the latter, but it is probable 

 that it also contained, and in larger numbers, a second 

 microbe (?), which is Peronospora Ferrani. 



It may also be observed, the injection of Ferran's 

 culture liquid into the intestines of guinea-pigs pro- 

 duced no effect, while subcutaneous injections soon 

 killed these animals and distinctly affected men. This 

 is precisely the opposite effect to that observed by 

 Nicati and Rietsch at Marseilles, and by Bochefontaine 

 in Paris. 



This is a crucial difference, since it shows that 

 the two microbes are not identical, and all our know- 

 ledge of cholera tends to show that its. microbe has 

 a special action on the intestines.* 



However this may be, Ferran carried on his 

 culture experiments in the endeavour to obtain an 

 attenuated microbe which might serve for preventive 

 inoculations. He believes that he has succeeded, and 



* The experiments made by Gibier and Van Ermengen in August, 

 1885, confirm this opinion. After inoculating a certain number of 

 guinea-pigs, according to Ferran's hypodermic method, with a virulent 

 culture liquid, and giving them time to recover, the same liquid was 

 injected into the stomach of these animals, and they all died with the 

 symptoms and lesions of cholera 



