S-1 Original Faccine Pock Institution, 



pock, through its stages of pimple, vesicle, scabbing, and 

 scarring. 



3. The evidence from the preceding sources of observa- 

 tion is various, numerous, and uniform, in establishing 

 uniformly the law, 



That vaccine ^fATTER possesses the property op 



OPPOSING THE AGENCV OF VARIOLOUS MATTER; BUT 

 VARIOLOUS MATTER HAS NOT THIS POWER AGAIN6T THE 



VACCINE;— the counteracting power is not mutual, it is on 

 one side only. 



6. Concerning the application to practice, it seems, from 

 the establishment of the law just enunciated, to be a con- 

 clusion ajortion, that a constitution in which the appro- 

 priate agency of vaccine matter has been exerted, is render^ 

 ed incapable of having the appropriate variolous agency 

 excited ; but, 



7. The numerous occurrences of the small pox during 

 the present epidemic variola, in persons who have been 

 supposed to have been vaccinated, prove that the process of 

 vaccination had not been duly excited. These failures af- 

 ford no objection to the principle, but a great one to thq 

 mode of practice ; and it is fortunate for the public, though 

 a misfortune to individuals, that the current year has mani- 

 fested the insecurity of many persons who have been ino- 

 culated for the cow-pock, as it may be the means of se- 

 curity for the future. 



The above propositions, which are the result of a great 

 variety of trials instituted with patient diligence, confirm 

 the foundation already very strongly established by an infi- 

 nite number of instances of inoculation in common pracr 

 tice, that it is a law, that the human animal oeconomy 

 is rendered unsusceptible of the variolous disorder, by hav- 

 ing gone tlirough the cow-pock. 



A small proportion of persons have certamly taken the 

 small pox after supposed yacciiiatipn ; and this it was pre- 

 dicted would be the case long ago, in the " Report of this 

 Institution,'' and in another work, " The Statement of 

 Evidence;" and it is now asserted, that in a future epide- 

 mical small-pox it may reasonably be expected that many 

 more will take that disorder. But the late failures and in- 

 security of niany persons already inoculated for the cow- 

 pock afford i\o evidence sjgainsl the efficacy of vaccination ^ 

 they only manifest, 



1 , That some years after the new practice the history of 

 vaccine affection was not sufficiently investigated to afford 

 rales of secure practice, 



2. That 



