ON THE INFLUENCE OF WEATHER UPON MORTALITY. dW 



of a single line. It indicates either a vast increase or diminution of pressure 

 upon every point of surface of the body, — a pressure which normally is equal to 

 that of fifteen pounds of dead weight to the square inch, and yet, a pressure so 

 wonderfully adapted to our necessities that we are unconscious of its presence. 

 So that, although in dealing with this part of the inquiry we are confined, with 

 very few exceptions, to movements within the thirtieth inch of the barometric 

 scale, we are not to suppose that such limited movements are of trifling, but that 

 they are of all-important value. 



Mean Height of Barometer reduced to Sea-level and 32° F. 



A comparison of the means of the four sections in Table C, between the mean 

 height of the barometer and the mortality from all causes, leaves us in uncer- 

 tainty as to the relations which these circumstances bear to each other. It is 

 indicated in the following table : — 



Section. Mortality from all Causes. Mean Height of Barometer. 



Maximum Section, 269-49 29-800 



Major Section, 233-25 29-868 



Minor Section 214-26 29-862 



Minimum Section, 185-85 29842 



Mean, 225-71 . 29-843 



The mean height of the barometer for the whole of each of the six years, as com- 

 pared with the mortality for the corresponding periods, is shown as follows :— 



Tear. 



1860, 

 1862, 

 1857, 

 1858, 

 1861, 

 1859, 



Means, 



Average Monthly Mortality 

 from all Causes. 



Mean Height of B 



244-2 



29-785 



229-2 



29-812 



227-5 



29-893 



225-5 



29-916 



214-9 



29-838 



212-7 



29-817 



225-7 



29-843 



In both of these tables the lowest reading of the barometer corresponds with 

 the highest death-rate. In both, the two lowest readings of the barometer cor- 

 respond respectively with the highest and lowest death rates, with a minute 

 fractional difference in the latter table, the second lowest reading being that of 

 the mean of 1862. In the latter table the highest barometric reading corresponds 

 with the mean of the mortality ; in the former, the highest barometric reading 

 stands opposite a much higher death-rate. The only point of resemblance between 

 the two being that first mentioned, indicating a maximum of deaths with a mini- 

 mum of atmospheric pressure. But we must not remain satisfied with the value 

 of this indication alone. 



VOL. XX II I. PART II. 4 s 



