GEORGE FLEMING 
6.0 
Chauveau notes in the course of his remarks, that if the other 
supposed vacciniferous animals—the gout, sheep, dog, etc.—show 
more or less distinct eruptions when they are vaccinated, the virus 
cannot be indefinitely cultivated upon them ; it loses its activity 
very rapidly, often in the first generation. 
With regard to the protective influence of one attack of variola 
from subsequent attacks, there can be no doubt; and this pro¬ 
tection has been sought for, with a view to preventing the more 
serious variola of certain species of animals, by inoculating them 
with the virus of a less malignant variola of another species. But 
here, again, we find evidence in support of our view, that every 
species has its own particular variola. Human small-pox, readily 
communicated from a diseased to a healthy person, can scarcely 
be transmitted, if at all, to the lower animals; while horse-pox 
and cow-pox are easily transmissible to a number of species, and 
in man and the horse and cow, when inoculated, will certainly en¬ 
sure against the natural disease. But we have seen that sheep- 
pox is not communicable to other animals (if we except the few, 
and not very reliable, instances recorded), and that vaccination 
will not protect ovines from their special variola. 
But it must be confessed that experimental pathology has here 
an almost virgin soil to cultivate ; for we know but little of the 
degree of inter-communicability of the differen t variolse, or of 
the protection they mutually afford against each other’s operation- 
The subject is full of interest, and of the deepest importance to 
mankind, and that it lias been so utterly neglected is one of the 
mysteries which overhangs many other serious problems in 
pathology. 
I trust that the grave fallacy that vaccinia is only human 
variola modified by transference to bovines, will no more be 
heard of; and that the claims of comparative pathology to recog¬ 
nition as a worthy helpmate to human pathology in the elucida¬ 
tion of this and other subjects in medicine, may be conceded and 
acted upon. 
