234 
A Paper, by Messrs. A. Ransome and G. V. Vernon, 
was read by Mr. A. Ransome, entitled, “ Contributions to 
Medical Meteorology.” 
After a short history of the attempts which have been made 
to connect the prevalence of disease with certain atmospheric 
conditions, special mention was made of the weekly returns of 
new cases of diseases furnished by upwards of two hundred 
medical men to the General Board of Health of London, from 
April 11th, 1857, to the week ending November 6th, 1858. 
These returns are accompanied by meteorological observations 
made at six stations in and out of London, and although in 
some instances imperfect, the deficiencies are not such as to 
prevent their use in the present inquiry. 
The medical and meteorological returns were projected 
upon separate charts, so as to form curves, which represent 
the prevalence of the disease, or the state of the atmosphere 
at any particular time,* and then by careful analyses of the 
two series of facts, and comparisons of the two charts, the 
following conclusions were drawn respecting; 
1. DiarrhcBa. A high mean temperature (above 60°) 
would seem to have a powerful influence in predisposing to 
this disease, when continuous, causing a rapid increase in the 
number of cases. A temperature below 60° appears to be 
unfavourable to its progress, and these actions are generally 
most evidently shown, when the temperature is above or 
below the average of the season. 
2. DyseMtery seems to be influenced by the variations in 
the mean temperature, but in less degree than diarrhoea, the 
effect not being generally traced in the lesser undulations of 
the curve. Increased atmospheric pressure seems to be 
unfavourable to the progress of the disease, high readings of 
the barometer being nearly always accompanied by diminished 
prevalence of dysentery. 
* In each instance of defective return, the probable amount of error arising from 
this source was marked upon the chart. 
