ON THE INFLUENCE OF WEATHER UPON MORTALITY. 



323 



Now, if I take the mean of the averages of all the months with a barometric 

 reading above the mean of the six corresponding months, and the mean of the 

 averages of all the months with a barometric reading below the mean of the six 

 corresponding months, the result is the same, though not, of course, so distinctly 

 shown : — 





Jan. 



Feb. 



March. 



April. 



May. 



June. 



Means. 



Average mortality of the months with ^ 

 a mean height of barometer above 1 

 the mean of the six corresponding t 

 months, ) 



Average mortality of the months with '\ 

 a mean height of barometer below 1 

 the mean of the six corresponding t 

 months, . . ) 



253-8 

 276-9 



273-2 

 241-7 



246-6 

 253-3 



246-9 

 2:^8-8 



212-7 

 226-3 



204-4 

 2170 



224-8 



225-0 





July. 



August. 



Sept. 



Oct. 



Nov. 



Dec. 



Avei*age mortality of the months with ^ 

 a mean height of barometer above ( 

 the mean of the six corresponding t 

 months, ) 



Average mortality of the months with ^ 

 a mean height of barometer below ( 

 the mean of the six corresponding C 

 months, j 



206-7 

 202-4 



192-7 

 182-7 



195-9 

 171-3 



195-5 



200-9 



240-5 

 230-2 



228-5 

 257-5 



Again : the mean height of the barometer for the whole period of six years is 

 29 •843. Now, if I take this reading as a standard of reference, I find that of the 

 seventy-two months thirty-eight afford a higher, and thirty-four a lower mean 

 reading, and the result, in regard to the ratio of mortality from all causes, is the 

 same as was observable when I employed the means of the corresponding months 

 as standards of reference ; namely, that the mortality is greatest with a low read- 

 ing of the barometer: or more clearly thus : — 



Average mortality of thirty-four months, in which the mean height of the barometer for 



each month was below 29-843, ......... 228-14 



Average mortality of thirty-eight months, in which the mean height of the barometer for 



each month was above 29-843, ......... 223-52 



Excess of mortality with a low barometer, 



4-62 



Again : if I arrange the months in seasons, representing winter by the months 

 December, January, and February, and the other seasons accordingly, I find that 

 of the eighteen winter months, the mean height of the barometer in ten was 

 below, and in eight above 29-843 : of the eighteen spring months the mean height 

 of the barometer in teii was below, and in eight above 29*843 : of the eighteen 



VOL. XXIII. PART II. 4 T 



