2X8 



Cholera iit Relation to Certain Physical Phenomena. [part i. 



TABLE XIX. 



Average monthly Tem'p&rature (23 years) compared with Cholera-prevalence. 



and October differ only by 1°0, but March is a month of maximum, October of 

 medium, prevalence : — 



Atmospheric Temperature [mean of 23 ! 

 years]. 



Total monthly Cholera (Deaths) [38 I 

 years]. "j 



DiAGBAM 2. — Atmospheric Temperature and Cholera-prevalence in Calcutta, 



Whilst this is the case, there is at the same time some evidence which seems to 

 be in favour of the temperature exerting a subordinate influence on the prevalence. 

 Taking the months from November to April, we get the following results ; 



TABLE XX. 



Temperature and Cholera from November to April. 



Starting from November, we have two months of diminishing temperature and 

 prevalence followed by three months of increasing temperature and prevalence. This 

 alone would hardly afford ground for any positive conclusion ; but we shall find here- 

 after, in considering the data regarding other conditions, that some disturbing influence 

 manifests itself during December and January, breaking in on the coincidence between 

 the prevalence of cholera and those conditions which otherwise correspond in their 



