To those already adduced in the former part of my first treatise
[Footnote: See pages 217, 218, 219, 221, 223, etc.] many more
might be adduced were it deemed necessary; but among the cases I
refer to, one will be found of a person who had the cow-pox
fifty-three years before the effect of the smallpox was tried
upon him. As he completely resisted it, the intervening period I
conceive must necessarily satisfy any reasonable mind. Should
further evidence be thought necessary, I shall observe that,
among the cases presented to me by Mr. Fry, Mr. Darke, Mr.
Tierny, Mr. H. Jenner, and others, there were many whom they
inoculated ineffectually with variolous matter, who had gone
through the cow-pox many years before this trial was made.

It has been imagined that the cow-pox is capable of being
communicated from one person to another by effluvia without the
intervention of inoculation. My experiments, made with the design
of ascertaining this important point, all tend to establish my
original position, that it is not infectious except by contact, I
have never hesitated to suffer those on whose arms there were
pustules exhaling the effluvia from associating or even sleeping
with others who never had experienced either the cow-pox or the
smallpox. And, further, I have repeatedly, among children, caused
the uninfected to breathe over the inoculated vaccine 'pustules
during their whole progress, yet these experiments were tried
without the least effect. However, to submit a matter so
important to a still further scrutiny, I desired Mr. H. Jenner to
make any further experiments which might strike him as most
likely to establish or refute what had been advanced on this
subject. He has since informed me "that he inoculated children at
the breast, whose mothers had not gone through either the