TIIE IIORSE. 169 



Transmission to other Species of Animal Life. 



Glanders also occurs in the ass and male, but I am inclined to 

 the opinion that it is originally an equine disease, and that when it 

 attacks these other solipeds, it is due to infection from, or by means 

 of, a diseased horse. 



It is also transmissible to man and all the domestic animals, ex- 

 cept to cattle. 



Sheep are especially susceptible to infection. Goats have been 

 known to acquire the disease when kept in the same stable with 

 diseased horses. The disease has been observed, or intentionally 

 produced, in dogs, cats, prairie-dogs, white bears, lions, mice, 

 Guinea-pigs, rabbits, and, according to Gerlach and Spinola, the hog 

 also, although no generalization of the disease appeared to take place 



in them. 



Geographical Distribution. 



Glanders is fast becoming a regular cosmopolite. "With the ex- 

 tension of civilization, diseases of man and animals follow a similar 

 course. If the march of empire makes its way westward, disease 

 accompanies it. While nearly all the contagious diseases of man 

 and animals are lost in history — that is, come to us with the earliest 

 historical records — still, during this period, we can follow their 

 westward movement along with the tide of Aryan civilization. 



In civilized lands the extension of all contagious diseases bears 

 direct relation to the intelligence of the government in taking 

 means to suppress them, and the frequency and ease of travel and 

 intercourse. 



This is naturally limited, in one way or another, by the peculiar 

 characteristics of the inficiens (cause) in each disease. 



Glanders has followed the same course. At one time it was said 

 not to prevail in hot climates, but we now know that it has acquired 

 an alarming extension, and frequently breaks out at the different 

 cavalry stations of the British forces in India and other tropical 

 countries. 



Where there is little or no intercourse with other parts, there is 

 little or no glanders, as in Iceland and other northern countries. 



This led to the assumption that it did not thrive in such a cli- 

 mate, and that it steadily increased as we proceeded from the north 

 to the south, until we arrived at tropical limits. 



This is all wrong ; the occasions to infection — with lack of sani- 

 tary police — being given, glanders will appear as frequently in one 

 climate as another. 



