ESSAYS ON BACTERIOLOGY. 37 



in the new victim. The micrococci of gonorrhoea 

 have been artificially cultivated in only a few in- 

 stances; the procedure is very difficult, and the cul- 

 tiires soon die. A few successful inoculation experi- 

 ments have been made upon men, but we should like 

 to see a larger measure of proof before we lay aside all 

 doubt. Certain it is, however, that the remaining 

 doubt is very slight. 



As to cholera, there is but a shadow of uncertainty 

 remaining that the comma bacilli of Koch are the 

 specific cause of the disease. Whatever tmcertainty 

 there is, is due to the lack of inoculation experiments 

 upon man. One accidental case has probably settled 

 the matter, but one case is hardly sufficient. In all 

 other respects the evidence is complete. There has 

 been discovered a rapid method of identifying cholera 

 cultures by the production of a violet-red or purplish- 

 red color tipbn the addition of pure sulphuric acid. 

 This method may be of great value for the purpose of 

 quick diagnosis in a given case. 



The Koch-Eberth typhoid bacillus remains about 

 where it was. It is, in all probability, the specific 

 germ, but in the absence of the final test, i. e., inocu- 

 lations, some uncertainty remains. Vaughan is skep- 

 tical in regard to this bacillus, believing that typhoid 

 may be due to more than one cause; in other words, 

 that it is not a specific disease. Certainly most au- 

 thorities do not agree with this view. 



Of diphtheria, it seems to be about settled that the 



