IMMUNITY. 377 



toxin ; the brief immunity that accompanies 

 the cure, results from stimulation of the natu- 

 ral defensive forces of the organism, and from 

 the rendering of these forces active, and is an 

 accessory phenomenon which does not con- 

 tribute to the cure. Such curative effect as 

 we strive to obtain with serum, and do obtain 

 in such very different degrees, must be much 

 more general in character than that obtained 

 by " specific " antidotes against " specific " 

 poisons, and can be brought about in a far 

 simpler way. Even in those cases in which 

 we are unwilling to relinquish the specific dis- 

 ease germs as the starting-point in our quest 

 for a curative substance, we may well find 

 some way to spare ourselves the time-robbing, 

 expensive and circuitous route through the 

 body of animals. 



Are There Protective and Curative Inocula- 

 tions That Are Non-Specific ? 



It was shown, in 1889, by Woodhead, Wood 

 and Hueppe that it is possible to immunize 

 animals against anthrax by inoculating them 

 with the bacillus of green pus (B. pyocyaneus), 

 and its metabolic products. It was then shown 

 by Hueppe, and confirmed by Klein and 

 Sobernheim, that it is possible to immunize 

 animals against cholera by employing many 



