150 Epidemics. 



unity, takes cognizance of the slightest variation of material 

 change on the surface of the sun. But this natural sequence of 

 perception of a force, in relation to distance, in two bodies 

 mutually affected by distance, is real and determinable ; but, 

 in relation to material disturbance of matter on the surface 

 of the globe as an efficient agent to promote disease, it is, so 

 far as we yet know, perfectly innocuous, and its case must 

 be dismissed as a true bill of cause to epidemic or endemic 

 disease, as not proved. 



Hence, as an active agent in promoting epidemic or en- 

 demic disease, the sun may be allowed to pass muster as 

 being a non-active agent in initiating or producing epidemic 

 or endemic disease, unless it be sun-stroke, the prickly heat 

 of tropical climates, and liver affections, by, in part, sus- 

 pending the functions of the lungs, as promoters of heat, and 

 throwing a great plus of hydrogen and carbon on the liver, 

 instead of excreting them by the lungs, as water and car- 

 bonic acid, when aided by the absorption of oxygen from the 

 atmosphere. 



Between earthquakes, volcanoes, and epidemics no direct 

 co-relation can be established, since small-pox, influenza, 

 plague, fevers, and cholera, etc., appear quite independent 

 of these terrestrial disturbances. For instance, plague has 

 affected certain countries and localities with great intensity, 

 as Marseilles in 1720, Naples 1656, London 1664-6, Moscow 

 1770, Bassora, Persia, 1772, and many other places at 

 particular times between these periods ; but between the 

 advent of earthquakes and volcanic eruptions, saving catarrh,, 

 as the mechanical effect of fine dust proceeding from the 

 first outburst of Mount Hecla, there does not appear to be 

 any regular coincidence between earthquakes and epidemics. 



It is quite true that epidemics are constantly recurring, 

 and so are earthquakes, but at very different parts in the 

 earth, and by no means in a certain order, in relation tO' 



