HISTORICAL. 297 



Gaffky (1884). This author confirmed Eberth's observa- 

 tions on the occurrence of the bacilli in the organs of 

 typhoid cases, and succeeded in obtaining from the spleen 

 pure cultures in gelatine. He further recognised very 

 fully the morphological character of the bacilli both in 

 cultures and when occurring in the body, though he 

 described them as spore-bearing, an observation which, as 

 we shall see, is now considered erroneous. He noted the 

 growth on potatoes as characteristic, and this is still looked 

 on as an important point. He held that the bacilli were 

 not putrefactive, as he found they did not produce putre- 

 factive effects on artificial media ; but all his attempts to 

 reproduce by their means the disease in different species 

 of animals (including monkeys) were unsuccessful. This 

 difficulty has not been fully overcome. The position, 

 therefore, was that in the great majority of cases of typhoid 

 fever, characteristic bacilli could be found and isolated in 

 pure culture, but that these did not give rise to the disease 

 in animals. 



During the years succeeding the publication of the 

 work of Eberth, Koch, and Gaffky, the results of these in- 

 vestigators were confirmed so far as they went, but little 

 advance was made towards a clearer knowledge of the 

 causation of the disease. The discovery in 1885 of 

 another micro-organism closely resembling the typhoid 

 bacillus and normally appearing in the human intestine, 

 caused questionings as to the bacillus of Eberth having a 

 causal relationship to typhoid fever. In the year named, 

 Escherich, working on the first appearance of organisms in 

 the bowel of the new-born infant, described a bacillus 

 which he named the bacillus coli communis (often sub- 

 sequently named the bacterium coli commune and also 

 Escherich's bacillus). About the same time Emmerich 

 described a bacillus which he found in the intestines of 

 the victims of a cholera epidemic at Naples, and to which 

 considerable attention was directed on account of the 

 author setting it up as the causal agent in cholera in 

 opposition to the vibrio of Koch. Resulting investigation 



