352 BACTERIOLOGY. 



Tizzoni, has up to the present not yielded con- 

 spicuously successful results. A decisive suc- 

 cess has, however, been claimed for the diph- 

 theria serum, sometimes in an exceedingly 

 unscientific and vehement fashion. Even sci- 

 entific congresses take sides by a majority 

 vote upon the question, purely scientific as it 

 is, and certainly not yet ripe for conclusion, 

 and seek to suppress the opposing view. The 

 exaggerations in the tuberculin affair, for 

 which afterwards no one was willing to stand 

 sponsor, are still sufficiently mortifying to 

 many clinicians, who by their manifest lack of 

 critical discernment in scientific matters, were 

 placed in a very unfortunate position. Yet 

 this experience seems, inside of four years, to 

 be completely forgotten. At present a some- 

 what more rational examination of the matter 

 is being made with the aid of collective in- 

 vestigations, but the statistical material leaves 

 almost everything to be desired. 



In the first place the statistical basis is of a 

 very dubious character. Conclusive control 

 experiments under absolutely similar condi- 

 tions do not exist at all. In certain cases the 

 period of introduction of the serum has coin- 

 cided with the occurrence of a mild epidemic. 

 The mortality from diphtheria varied from 

 1875-1891 between 6.2/ -34.i%, indifferent 



