Class II. i. 3. 9. OF SENSATION. 207 



fmall-pox : to all whom in that fituation it is dangerous, as it 

 generally produces mifcarriage, and frequently death. Dr. 

 Cappe, in an ingenious paper in the York Herald, obferves, that 

 the vaccine difeafe is never communicated but by contact, and 

 then only when the matter lies on the broken fkin ; and that 

 many women during pregnancy have paired through this dif- 

 eafe, and none have fufTered from it"; and that inftead of being 

 peculiarly dangerous to young infants, as the fmall-pox is, it 

 feems to be peculiarly mild to them. 



From all thefe circumftances it may be hoped, that the inoc- 

 ulation of the cow-pox may become fo general, and performed 

 io early in life, as totally to eradicate the fmall-pox ; by which 

 latter difeafe above two thoufand perlbns are (hewn by Dr. 

 Cappe, by the bills of mortality, to be annually deitroyed in a 

 part of London only. 



As the cow-pox is fo much lefs infectious than the fmall-pox, 

 it requires much more care - in the inoculation to give the difeafe 

 with certainty ; whence it fomecimes has happened, that a flight 

 inflammation from the punclure of the lancet has been miftaken 

 by the unlkilful for the vaccine difeafe : and I have heard of four 

 fuch patients in this country who have afterward taken the 

 fmall-pox. But as Dr. Woodville inoculated a thoufand people 

 with the fmall-pox, who had previoufiy received the cow-pox, 

 without one of them taking the infection, there can be no doubt 

 but that the four patients above mentioned had not previouily 

 undergone the vaccine difeafe ; and ought not therefore to dif- 

 credit this fortunate and wonderful difcovery. 



In the counties where the cows are fubjecl: to this difeafe, the 

 milking is performed principally by men-fervants ; and it is 

 there believed, as Dr. Jenner mentions, that the difeafe was pre- 

 viouily given to the paps of the cows by the hands of the men 

 who milked them, and who had previoufiy acquired the infec- 

 tious matter from the heels of horfes, which difcharged an acrid 

 fanies, when they had a difeafe called the greafe. This may be 

 worth further investigation ; as the prefervation of people from 

 the fmall-pox, by their having undergone the cow-pox, is fo won- 

 derful a phenomenon, fo contrary to our previous knowledge of 

 any analogy between the infeclious diieafes of men and quadru- 

 peds, that other facts equally furprifing may exift. May not the 

 fmall-pox have been originally acquired from the cow-pox ? 

 which latter, having been a much older difeafe, may by procefs 

 of time have become milder than the former : as the fmall-pox 

 is believed a If to have become much milder than formerly ; ow- 

 ing probably to the incapacity of receiving it, which exifts in 

 tliofe who have undergone that difeafe, having in procefs of time 



become 



