150 



THE CANADIAN NATURALIST. 



[Dec. 



14. Average Weekly Mortality of Adults and Children 

 above 12, for each month from Jan., 1855, to Dec., 1866 



Year. 



January 



February 



March 



April 



May 



June 



July 



August 



September. . . 



October 



November. . . 

 December. . . . 



Average week 

 for 12 months 



355 



4-7 



21-5 



1 6 . o 

 17.7 

 [6.2 



14.4 

 10.5 

 14-5 

 11. 4 

 14-0 

 10.7 

 12. ii 



856 1857 1858 1859 



5 11 



017 



014 



7 15 

 2 17 



4 IS 

 016 

 517 

 216 



.6 



■7 

 .2 



■S|i7- 

 .815- 

 .7116. 



• o!l2. 



.014. 



.0119. 



. 4 |i6. 

 ■7 13. 



•5|i4- 



5-9 



S60 



19 

 16 



20 

 16 

 19 

 23 

 19-3 



[8631864 



[Sr, 5 



!2.2 19. S 



: 9 . 5 !i8.2 

 ;o.o 21.7 

 '2.726. 8 

 9- 425-0 



51. S 24.O 

 5I.523.6 



.214. 

 • 2 21. 



•5 19' 



T 



.1, 



22.5 

 22.0 

 18.7 

 26.2 

 24.2 

 23.0 

 20.6 

 25.0 



23- 



23- 

 23-4 



22.5 



27-5 

 26.5 

 20.6 

 18.5 

 24 5 

 22.8 

 27.0 

 26.0 

 26.0 



23.6 



Average per 



week, in each 



month, for 12 



years. 



It was natural to expect that there should be some difference 

 between the mortality at different seasons of the year. It is found 

 in England, on the average of 10 years, that this difference does 

 not affect in the same degree the town and the country population. 



15. English Seasonal 



Variations between Town ana 



Country Mortality. 



The town excess is thus shown to be intensified most in summer, 

 and next in autumn; no doubt because the zymotic poisons are 

 rendered most active in the hottest weather, and their influence 

 continues till the frosts of winter. The effect of the heat in the 

 five plague years of London which have been recorded in history is 

 very noteworthy. The bills of mortality shew the following average 

 for every 1000 persons living. 



16. Plague Years in London. 



Winter Quarter : January, February, March 17 per 1000 living. 



Spring " April, May, June 20 



Summer " July, August, September 163 



Autumn " October, November, December 50 



Total 250 "or 1 in 4 



