492 Proceedings of Royal Society of Edinburgh. [suss. 
seen to be very much that of presanitary days (diagrams VIII. and 
VIIIa.). I do not mean to infer that there is no difference in the 
amount of disease present in a given epidemic, hut that a uniform 
Diagram VIII. 
force acting towards the limitation of an epidemic produces no 
perceptible effect on the form of the curve. In the case of 
Gloucester, the form of the curve has been calculated for the 
total cases ; for the severe cases (diagram IX.) ; and for the 
