Change of Incidence of Small-Pox. 105 



On the change of incidence of Small-Pox at different 

 ages during the years 1848-86. Part I. By R. F. 

 Gwyther, M.A. 



Received February 21st, 1888. 



It may interest the Society to see to what extent the 

 change of incidence of small-pox in regard to age, which 

 was noticed by our late Secretary and Editor, has con- 

 tinued to act, and I offer to the Society some tables which 

 I have prepared to illustrate the way in which that change 

 has displayed itself When I had nearly completed the 

 preparation I found that the subject had been treated by the 

 Registrar General in his report for 1880, and by the Medical 

 Officer of the Local Government Board in his report for 

 1884, and each of these reports contains an extended exami- 

 nation of the causes acting. My reason for preparing these 

 tables was, therefore, considerably weakened, and I should 

 not have brought them forward except that the tables are 

 fuller, and seem to indicate one or two points which I have 

 not seen noticed. The tables which I have prepared give 

 the death rates calculated for 1,000,000 living at the ages 

 given at the top of each column. I have taken so large a 

 number because, to many, whole numbers give a more 

 intelligible picture than places of decimals. 



I have kept the results for males and females separate, 

 because there is a considerable difference between the inci- 

 dence of small-pox on the two sexes at certain ages. 



The subject of this paper is well illustrated by an excel- 

 lent and interesting paper by Dr. J. C. Mc.Vail, read before 

 the Philosophical Society of Glasgow, in 1882, "On the 

 prevalence of small-pox in Kilmarnock in the 36 years, 

 H 



