VIII, B, 6 Ashburn et al.: Inoculation of Monkeys 441 



COMMENT 



We admit that this small series of experiments affords but 

 little proof of the correctness of our hypothesis as to the relation- 

 ship of variola and vaccinia.' On the contrary, we do not see 

 that it affords any evidence in disproof. The case of monkey 5, 

 although of little value standing alone, is certainly susceptible 

 of being cited as an instance of variola sine exanthemate, as an 

 instance of separation of the elements of smallpox virus (the 

 pock-producing or "B" part having acted on the monkey in 

 October; the toxaemia-producing, pyrogenic, or "A" element in 

 December), and as proof that vaccination protects against the 

 pock-forming element of smallpox rather, or to a greater degree, 

 than against the whole disease. We feel justified in restating 

 our hypothesis that smallpox is due to a dual and divisible virus, 

 one part of which is the cause of vaccinia and the pock stage of 

 smallpox, the other part being necessary for the production of the 

 highly contagious, febrile, general disease with an initial stage 

 and preliminary rashes. 



- This Journal, Sec. B (1913), 8, 17-28. 



122778 8 



