ON THE INFLUENCE OF WEATHER UPON MORTALITY. 



345 



Besume : On the Influence of Mean Temperature. 



Average monthly mean temperature of the six -winters (Dec, Jan., Feb.), . 38°-l 



,, ,, „ springs (March, April, May), 44°-4 



„ ,, ,, summers (June, July, Aug.), 56°'6 



„ „ ,, autumns (Sept., Oct., Nov.), 46°*4 



In the following table the upper lines represent the average mortality of the 

 months whose mean thermometric readings are severally above the standard of 

 reference, whilst the lower lines represent the average mortality of the months 

 with thermometric readings below the standard : — 





At all Ages feom 



Feom all Cabses at 



AU 

 Causes. 



Zymotic 

 Diseases. 



Phthisis. 



Bronchitis. 



0-5 

 Years. 



6-20 

 Years. 



20-60 

 Years. 



60, &c. 

 Years. 



Average mortality of ten winter months, with a ) 



mean temperature above 38°-l, .... J 

 Average mortality of eight winter months, with 1 



a mean temperature &eZow 38°- 1, . . . . j 

 Average mortality of eigJit spring months, with ) 



a mean temperature above 44°"4, .... J 

 Average mortality of ten spring months, with a 1 



mean temperatm-e below 44°-4, j 



Average mortality of eleveyi summer months, 1 



with a mean temperature above 56°-6, . . J 

 Average mortality of seven summer montlis, 1 



with a mean temperature 6eZow 56°-6, . . J 

 Average mortality of nine autumn months, with ) 



a mean temperature above 46°-4, . . . . j 

 Average mortality of nme autumn months, with ) 



a mean temperature below 46°-4, .... J 



245-51 

 271-11 

 223-81 

 248-35 

 201-40 

 199-97 

 190-22 

 225-14 



63-90 

 64-12 

 45-41 

 54-44 

 49 09 

 45-29 

 54-56 

 65-11 



29-25 

 31-74 

 34-17 

 35-46 

 29-43 

 30-77 

 23-10 

 25-47 



25-49 

 33 69 

 19-09 

 23-74 

 9-70 

 13-19 

 11-32 

 18-47 



116-60 



123-17 

 99-48 



111-58 

 94-73 

 88-36 

 92-28 



107-61 



23-23 

 24-04 

 24-25 

 24 53 

 20-96 

 23-19 

 2006 

 22-77 



64-71 

 74-64 

 63-41 

 7002 

 54-57 

 56-20 

 49-60 

 58-11 



41-10 

 48-76 

 36-72 

 42-01 

 31-13 

 32-37 

 28-12 

 36-40 



The foregoing table — 



1. Corroborates the suggestion previously made, that the relationship between 

 mortality from all causes and mean temperature is inverse when the mean tem- 

 perature is below 50°, and direct when the temperature is higher. Probably the 

 bad effects of a high mean temperature are not perceptible until it has been 

 maintained for some time at or above 56°"6. In general terms, the relationship 

 between mean temperature and mortality from all causes is inverse in winter, 

 spring, and autumn, but direct in summer. 



2. Seems to indicate a relationship between mean temperature and mortality 

 from zymotic diseases similar to that between mean temperature and death from 

 all causes ; namely, inverse in winter, spring, and autumn, but direct in summer. 

 The previous suggestion was, that the relationship was variable and uncertain. 



3. Corroborates the suggestions previously made concerning the influence of 

 mean temperature upon the death-rate from Phthisis Pulmonalis ; namely, that 

 a low winter temperature increases the mortality from phthisis, but only to a 

 remarkable extent when the mean temperature is very low, and continuously so ; 

 and that a high summer temperature does not increase the fatality of phthisis. 



VOL. XXIII. PART II. 5 B 



