436 



SPIRILLUM CHOLERA ASIATIC JE. 



Injection of 

 cultivations 

 into the 

 duodenum. 



occasions it seemed as if a positive result had been 

 obtained, but this was due to error in the experiments ; 

 thus in Thiersch's experiments white mice became ill 

 after having been fed on filter paper impregnated with 

 decomposing cholera dejecta, but they also became ill 

 in the same manner if the cholera dejecta were omitted 

 from the experiments ; in like manner in the experi- 

 ments made quite recently by Richards in which swine 

 were fed with very large quantities of cholera dejecta 

 and died in from J to 2| hours, we may assume with 

 certainty, from the suddenness of the action, as well as 

 from the circumstance that the resulting disease could 

 not be transmitted in any way to other animals, that in 

 these experiments he had to do with poisoning from 

 poisonous products contained in the dejecta, and not 

 with an infection. 



Notwithstanding this slight prospect of success the 

 experiments on animals have been again taken up by 

 Nicati and Rietsch, Yan Ermengem, Koch, &c., since 

 the discovery and cultivation of the comma bacilli ; and, 

 as a matter of fact, these authors have succeeded in 

 finding a mode of infection by which a process at any 

 rate similar to cholera can be set up in animals by 

 means of pure cultivations of these organisms. Accord- 

 ing to the facts mentioned above as to the immunity of 

 these animals to every sort of natural infection, it could 

 hardly be expected that more than a similarity in the 

 symptoms would be obtained, and even this result could 

 only be looked for by the employment of an artificial 

 mode of infection. In view of these unfavourable pros- 

 pects of experiments on animals it is more correct to lay 

 the greatest stress in the proof of the etiological role 

 of comma bacilli on the demonstration of their constant 

 and exclusive occurrence in cholera, and not on the 

 experiments on animals; their constancy has been so 

 completely shown that as a matter of fact the experi- 

 ments on animals can be dispensed with. 



Starting from the supposition that the seat of the 

 action of the comma bacilli is the small intestine, but 

 that infection by the mouth must be a difficult matter, 



