LEPROSY AND TUBERCULOSIS 233 



natural resisting powers and are less affected. The 

 struggle therefore resolves itself into a deliberate contest 

 for supremacy in the animal kingdom between the 

 highest and the lowest representatives. This considera- 

 tion should still further fortify us to continue the fight. 



LEPROSY AND TUBERCULOSIS 



Just as tick fever or plague teaches us a very signifi- 

 cant lesson as regards tlie rise and fall of disease in 

 the history of mankind, so to-day the bacterial diseases 

 known by the respective names of leprosy and tuber- 

 culosis also give us very much cause for reflection. 



Leprosy is a very widely distributed disease. It 

 can still be seen in its most flourishing condition in 

 the tropics, but it is by no means limited to tlie 

 warmer latitudes ; there is much of it still in the north 

 of Europe. And we must all be familiar with the 

 fact that formerly it was not only very prevalent in 

 Europe, but even in this country. The precise manner 

 in which it is transmitted from person to person is not 

 known. Numerous theories to account for its spread 

 have been from time to time propounded, but they 

 are none of them satisfactory. Beauperthuy, who 

 had a very considerable experience of the disease, 

 regarded the insect vermin Sarcoptes scaheii as taking 

 a very leading share in its transmission ; he also 

 viewed with suspicion the house fly. It is a fact 

 that the sarcoptes is very frequently associated with 

 leprosy ; and, just as in the case of the tick- and 

 flea-carried diseases, there may be some intimate 



