176 messrs. ransome and vernon on the influence 



Eheumatic Fever. 



The curve of this disease is not sufficiently extended to 

 admit of accurate comparison with the meteorological 

 curveSj and therefore no decided conclusion can be drawn 

 respecting it. 



Our data, however, would bear out the observation of 

 Sydenham : " This disease may come on at any time ; it is 

 commonest^ however^ during the autumn.^^ — Obs. Med. 

 vi. 5 (i). 



Measles. 



In its chief undulations, the measles curve seems to rise 

 with the fall of the temperature, and vice versa ; and 

 the influence of this element is best marked when it 

 is above or below the forty-three years^ average. 



These two propositions will be proved by the following 

 observations. 



In the spring 1857 the largest number of cases occurs 

 in the week ending May 2nd, when the temperature 

 reaches its minimum (42°) this season, and when more- 

 over it is 7*^° below the forty-three years' average. The 

 disease curve then gradually declines as the temperature 

 rises until August, when there is a sudden temporary 

 increase in the number of cases (of whooping cough also), 

 and a considerable fall from the July temperature, although 

 the latter is still above the average, and remains so through- 

 out the autumn. After this temporary deviation the 

 temperature rises to 68° (7° above the average), and the 

 number of cases diminishes again, but continues to do so 

 for a fortnight after the temperature begins to fall. 



From September 12th the disease curve rises gradually 



maturity as the year advances ; with the decline of the year it declines also. 

 Mnally the frosts of winter transform the atmosphere into a state unpro- 

 pitious to its existence. — Sydenham, Medical Oiservations, iii. 2 (5). 



