VII 



CHOLERA 



H E study of cholera was the hardest of all the 



hard labours of bacteriology ; it took years of 

 work in all parts of the world, and the difficulty and 

 disappointments over it are past all telling*. Koch's 

 discovery of the comma-bacillus (1883) raised a 

 thousand questions that were solved only by infinite 

 patience, international unity for science, and inces- 

 sant research; and the Hamburg epidemic (1892) 

 marks the time when the comma-bacillus was at 

 last recognised as the cause of cholera. A mere 

 list of the men who did the work would fill page 

 after page ; it was bacteriology in excelsis, often 

 dangerous, # and always laborious. 



* " In order to prove that this vibrio is the cause of Asiatic 

 cholera, several tests upon themselves have been voluntarily 

 made by investigators in laboratories. These were carried out 

 in Munich and in Paris. The results to the experimenters 

 were sufficiently severe to indicate positively the pathogenic 

 character of the spirillum, and its capacity to produce cholera- 

 like infections. Such experimentation is, of course, to be 

 deprecated ; indeed, the occurrence of accidental laboratory 

 infections, one of which ended fatally, furnished the necessary 

 final proof of the specificity of the cholera vibrio, and rendered 

 unnecessary any exposure to the risks belonging to voluntary 

 inoculation." (Dr Flexner, Stedman's Twentieth Century 

 Practice ; vol. xix., 1900.) 



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