210 PHILOSOPHICAL TRANSACTIONS. [aNNO 17 16. 



ages and constitutions ; but in general the eruption begins to show itself on the 

 7th day, which is therefore considered as a critical day. In like manner the 

 symptoms vary according to the diversity of temperament, habit of body, and 

 other circumstances ; being sometimes more slight, sometimes more violent ; 

 but in general they differ in no respects from those which accompany the 

 natural small-pox, except in being milder. Many on whom the operation is 

 performed are scarcely at all disordered. 



The inoculated small-pox is almost always of the distinct sort, and the 

 pustules few in number; 10, 20, 30, seldom 100, and very rarely 200, in 

 the same subject. 



It is to be remarked, 1st. That in some instances a single puncture in the 

 arm has sufficed for communicating the small-pox ; and that although in such 

 persons but few eruptions appeared, they nevertheless continued afterwards ta 

 be proof against infection. 2dly, That in some instances, owing to a peculiarity 

 of constitution, or to the want of activity in the matter employed, the opera- 

 tion did not take effect. Such persons were found as liable to take the infection 

 in the natural way, whenever the small-pox prevailed epidemically, as those who 

 had never been inoculated. 3dly, That the inoculated places always rise into 

 pustules; and in some instances large suppurations or abscesses are formed there. 

 Sometimes, but very rarely indeed, abscesses have formed in the glandular parts. 

 Lastly, that hitherto scarcely a single instance had occurred of inoculation having 

 terminated fatally; although it had been performed upon persons of all ages and 

 constitutions: indeed, when the operation is performed in a proper manner, and 

 upon subjects duly prepared for it, it is attended with perfect safety. The 

 small-pox thus produced is much milder than the small-pox taken in the natural 

 way, the eruptions being of the distinct sort, and the febrile symptoms much 

 slighter. To these considerations are to be added the advantages gained by 

 choosing the season of the year the most favourable for the operation, and by 

 preparing the constitutions of those on. whom it is to be performed, by a proper 

 regimen and diet.* 



• A similar mode of inoculation, under the appellation of bvt/ing the small-pox, seems to have been 

 practised in various parts of the East, from time immemorial. (See Woodyille on Inoculation.) And 

 even in Wales, from a very remote period, under the same name, as appears from the communica- 

 tions transmitted to the R. S. on this subject by Dr. Perrot Williams and Mr. Wright. See Phil. 

 Trans, vol. xxxii. It is highly curious, says Dr. Woodville, that in so many distant nations, differing 

 widely in manners, customs, laws, habits, and religion, that the art of inoculation should be geaerally 

 known by the name of buying the small-pox. He considers it as a remarkable proof of its great anti- 

 quity, that the less civilized part of mankind, or people of the most simple and uniform habits, have 

 retained this custom the longest. 



