th their edges more elevated than
their centre and of a color distinctly approaching to blue. Absorption
takes place, and tumors appear in each axilla. The system becomes
affected, the pulse is quickened; shiverings, succeeded by heat, general
lassitude, and pains about the loins and limbs, with vomiting, come on.
The head is painful, and the patient is now and then even affected
with delirium. These symptoms, varying in their degrees of violence,
generally continue from one day to three or four, leaving ulcerated
sores about the hands which, from the sensibility of the parts, are very
troublesome and commonly heal slowly, frequently becoming phagedenic,
like those from which they sprang. During the progress of the disease
the lips, nostrils, eyelids, and other parts of the body are sometimes
affected with sores; but these evidently arise from their being
heedlessly rubbed or scratched by the patient's infected fingers. No
eruptions on the skin have followed the decline of the feverish symptoms
in any instance that has come under my inspection, one only excepted,
and in this case a very few appeared on the arms: they were very
minute, of a vivid red color, and soon died away without advancing to
maturation, so that I cannot determine whether they had any connection
with the preceding symptoms.

"Thus the disease makes its progress from the horse (as I conceive) to
the nipple of the cow, and from the cow to the human subject.

"Morbid matter of various kinds, when absorbed into the system, may
produce effects in some degree similar; but what renders the cow-pox
virus so extremely singular is that the person that has been thus
affected is forever after secure from the infection of small-pox,
neither exposure to the variolous effluvia nor the insertion of the
matter into the skin producing this distemper."(2)

In 1796 Jenner made his first inoculation with cowpox matter, and two
months later the same subject was inoculated with small-pox matter. But,
as Jenner had predicted, no attack of small-pox followed. Although fully
convinced by this experiment that the case was conclusively proven, he
continued his investigations, waiting two years before publishing his
discovery. Then, fortified by indisputable proofs, he gave it to the
world. The immediate effects of his announcement have probably never
been equalled in the history of scientific discovery, unless, perhaps,
in the single instance of the discovery of anaesthesia