INOCULATION. 
98 
the newly-formed cracks in the heels, fimilar to what 
fometimes exudes from eryfipelatous blifiers, which give9 
the difeafe. He is led to this opinion, from having often 
inferted pus taken from old fores in the heels of horfes, 
into fcratches made with a lancet, on the found nipples of 
cow’s, which has produced no other effeft than fimple in¬ 
flammation. He is uncertain if the nipples of the cow 
are at all times fufceptible of being afted upon by the vi¬ 
rus from the liorfe, but rather fuf'pedts that they mull be 
in a Hate of predifpofition, in order to enfure the effeft. 
But he thinks it is clear, that, when the cow-pox virus is 
once generated, the cows, when milked with a hand re¬ 
ally infected, cannot refill the contagion, in whatever Hate 
their nipples may chance to be. He is alfo doubtful whe¬ 
ther the matter, either from the cow or the liorfe, will af- 
feft the found Ikin of the human body; but thinks it 
probable that it will not, except on thofe parts where the 
cuticle is very thin, as on the lips. 
At what period the cow'-pox was firffc noticed in Glou- 
cellerlhire is not upon record. The oldell farmers were 
not unacquainted with it in their earlieft days when it 
appeared upon their farms, w'ithout any deviation from 
the phenomena which it now exhibits. Its connection 
with the fmall-pox feems to have been unknown to them. 
Probably the general introduction of inoculation firll oc- 
caftoned the difcovery. Dr. Jenner conjectures that its 
rife in that neighbourhood may not have been of very re- 
anote date, as the practice of milking cows might former¬ 
ly have been in the hands of women only; and confe- 
quently the cows might not in former times have been 
sxpofed to the contagious matter brought by the men-fer- 
vants from the heels of horfes. He adds, that a know¬ 
ledge of the fource of the infection is new in the minds 
©f moll of the farmers, but has at length produced good 
confequences ; and that it feems probable, from the pre¬ 
cautions they are now difpofed to adopt, that the appear¬ 
ance of the cow-pox in that quarter may either be entire¬ 
ly extinguilhed or become extremely rare. 
With refpeCl to the opinion adduced, (Dr. Jenner ob- 
ferves,) that the fource of the infeClion is a peculiar mor¬ 
bid matter arifing in the horfe; although I have not (fays 
lie) been able to prove It from aClual experiments con¬ 
ducted immediately under my own eye, yet the evidence 
I have adduced appears to eltablilh it. “They who are 
not in the habit of conducting experiments, may not be 
aware of the coincidence of circumltances, necelfary for 
their being managed fo as to»prove perfectly decifive ; nor 
how often men engaged in profelfional purfuits are liable 
to interruptions, which difappoint them almoll at the in¬ 
fant of their being accomplilhed ; however, I feel no 
room for hefitation relpeCling the common origin of the 
difeafe, being well convinced that it never appears among 
the cows, except it can be traced to a cow introduced 
among the general herd which has been previoufiy infect¬ 
ed, or to an infeCted fervant, unlefs they have been milk¬ 
ed/by fome one who, at the fame time, has the care of a 
horfe affeCled with difeafed heels.” 
The following cafe, which we alfo quote from Dr. Jen¬ 
ner, would feem to ihow that not only the heels of the 
liorfe, but other parts of the body of that animal, are ca¬ 
pable of generating the virus which produces the cow- 
pox. “ An extenfive inflammation of the eryfipelatous 
kind appeared, without any apparent caufe, upon the up¬ 
per part of the thigh of a fucking colt, the property of 
Mr. Millet, a farmer at Rockhampton, a village near 
Berkeley. The inflammation continued feveral w'eeks, 
and at length terminated in the formation of three or four 
imall abfcefles. The inflamed parts were fomented, and 
dreflings w'ere applied by fome of the fame perfons who 
■were employed in milking the cows. The number of 
cows milked was twenty-four, and the whole of them had 
the cow-pox. The milkers, confining of the farmer’s 
wife, man, and a maid-fervant, were infected by the cows. 
The man-fervant had previoufiy gone through the fmall- 
pox, and felt but little of the cow-pox. The fervaut- 
maid had fome years before been Infected with the cow ■ 
pox, and (he alfo felt it now in a flight degree; but the 
farmer’s wife, who never had gone through either of thefe 
difeafes, felt its effefts very leverely. That the difeafe 
produced upon the cows by the colt, and from them con¬ 
veyed to thofe w’ho milked them, was the true and not the 
fpurious cow-pox, there can be fcarcely any room for fuf- 
picion ; yet it would have been more completely fatisfac- 
tory had the effects of variolous matter been afcertained 
on the farmer’s wife ; but there was a peculiarity in her 
fituation which prevented my making the experiment.” 
Subfequent authors have not been difpofed to adopt Dr. 
Jenner’s opinion that this difeafe derives its origin from 
the greafe in horfes. The doctor himfelf allows that he 
has not been able to prove it decifively by aCtual experi¬ 
ments ; and, to eftablilh a facl fo contrary to all analogy, 
perhaps no weaker evidence ought to be admitted. The 
only other beftial diforder with which we are acquainted, 
which is capable of being communicated by contagion to 
the human fpecies, is hydrophobia; but here the diforder 
is the fame in man as in the animal from which it derives 
it; and the analogy holds good in the propagation of the 
vaccine difeafe from the cow to her milker. But that the 
difcharge from a local difeafe in the heel of a horfe fhould 
be capable of producing a general diforder in the confli- 
tution of a cow, with fymptoms totally different, and that 
this new difeafe once produced fliould be capable of main¬ 
taining an uniform character in the cow and in man, 
feems a much greater departure from the ordinary pro¬ 
ceeding of nature. We are very far from faying that this 
is impoflible; for little indeed do we know of what Na¬ 
ture can or cannot do. All we mean to fay is, that a fa£l 
fo very extraordinary ought not to be haffily admitted. 
In Holftein, we are told that the farmers do not know 
of any relation exifting between the greafe and the cow- 
pox, at leaft a perfon who refided three years in that coun¬ 
try never heard of any. This, however, is certainty no 
proof. The fame communication which contains this re¬ 
mark (a letter from Dr. De Carro of Vienna to Dr. G. 
Pearfon) adds, “that in great farms men do not milk 
cows, but that in the fmaller ones that happens very of¬ 
ten ; that a difeafe of horfes, called mauke, (true German 
name for greafe,) is known by all thofe who take care of 
them ; that old horfes particularly, attacked with the 
mauke, are always put in cows’ llables, and there are at¬ 
tended by women ; and that it is particularly in h^rveft 
that men in fmall farms milk cows.” It mult be allowed., 
then, that in this fituation, fuppofing Dr. Jenner’s opi¬ 
nion well founded, the cow-pox was naturally to be look¬ 
ed for, and here accordingly we find it. Dr. Woodville, 
however, not being able at one period to procure vaccine 
matter, proceeded to try whether the difeafe could be ex¬ 
cited by inoculating the nipples of cows with matter of 
greafe; in conformity to the opinion that the cow-pox 
originated in the greafe. The numerous experiments 
made by the author, however, as well as by profeffor Cole¬ 
man, (of the Veterinary College,) in order to produce the 
difeafe in cows by the inoculation of the greafe matter, 
and other equine morbid fecreted fluids, proved unfuccefsful i 
In a note the curious faft is Hated, that, although the va¬ 
riola vaccina could not be produced in the cow’s teats by 
the inoculation either of variolous matter or of vaccine, 
matter from the cow, Mr. Coleman did fucceed in excit¬ 
ing the difeafe in the cow by inoculation of cow-pox 
matter from the human fubjeCl. From thefe experiments, 
and other conclufive reafons here Hated in Dr. Wood- 
ville’s Reports, 1799, that gentleman feems clearly to have 
proved the error of Dr. Jenner with refpeCl to the origift 
of the cow-pox in the greafe of horfes. 
Some people fuppofe, that the cow-pox derives its ori¬ 
gin from the fmall-pox ; and that the infeClion is com¬ 
municated to the cow by the hand of the milker; but 
this hypothefis is neither warranted by reafon, nor con¬ 
firmed by fail. There is.no analogy to render it proba¬ 
ble, that any poifon is thus mitigated by tranfmiflion 
tlirougfe 
