Change of Incidence of Sniall-Pox. 133 



that the most effective measures against the epidemic rise 

 of small-pox can be taken, when probably the history of 

 each case could be learnt, and the existence of endemic 

 centres of small-pox, possibly not in a malignant form, 

 could be discovered, and perhaps the circumstances which 

 allow of its existence disclosed. The epidemic of 187 1-2 

 was European in Its dimensions, and could not be so easily 

 guarded against, but most of our epidemics are more local, 

 and seem to Indicate that some epidemic cause has allowed 

 an existing disease to become malignant. 



''a 



%.'> _ KC*'.' yr 



