444 MICRO-ORGANISMS AND DISEASE [chap. 



the disease so produced in the guinea pig is cholera, any 

 more than has Finkler's comma bacillus, or any of the 

 other species of bacteria that are capable of producing 

 chemical poisons analogous to ptomaines. All that can be 

 said is, provided that conditions are established by which 

 the choleraic comma bacilli are enabled to grow and 

 multiply in the intestinal canal, these chemical poisons are 

 produced. 



This method of experimentation introduced by Koch 

 cannot therefore be held to prove a specific action of the 

 cholera vibrio on the guinea-pig, since after this method the 

 same result is produced with other bacteria, in no way con- 

 nected with cholera asiatica. Metchnikoff (Annales de 

 ITnstitut Pasteur, 1895) has shown that by choosing very 

 young rabbits, almost immediately after birth, it is possible 

 in a large percentage to produce by ingestion of culture of 

 the cholera vibrio rapid multiplication of the vibrios within 

 the alimentary canal and death of the animal in 24 — 48 

 hours ; I have repeated these experiments and can con- 

 firm them, but I have to add that the same result is ob- 

 tained with the vibrio of Finkler. 



While then the position of affairs, viz., whether the 

 vibrio of cholera (Koch) is or is not the real causa causans 

 of Asiatic cholera, is not altered by all these experiments on 

 the guinea-pig (subcutaneous, intraperitoneal, and intro- 

 intestinal injection), there have been made numerous 

 observations within the last three or four years (since the 

 Hamburg epidemic in 1892) which materially alter the 

 circumstances from what they were previously. Since 1886, 

 and up to that date the fundamental fact discovered by Koch 

 that the particular vibrio found by him in Asiatic cholera is 

 peculiar to cases of Asiatic cholera and to no other disease of 

 the intestine, its demonstration being therefore of the greatest 



