824 
W. H. DALRYiMPLE. 
to distant pastures, and in this way the disease is spread and 
crops up in the most unexpected localities, in the most unac-. 
countable manner without any appare^it cause. knowledge of 
this fact alone might be the means of preventing the spread of i 
the disease in many instances. The spore is the most difficult i 
stage of the germ to destroy, and is said to be able to withstand : 
our ordinary climatic influences for years, and is therefore capa- | 
ble of permanently infecting certain sections of the country, 
such as our own, where conditions seem to be favorable to its 
development. I 
With regard to the ways by which the contagion gains ac- ' 
cess to the circulation of the living animal, we have already al- | 
luded to one, viz.: by ingestion or swallowing contaminated 
food or water. This is known as the intestinal mode of infection, 
and produces death more rapidly than any of the other modes, i 
for the reason that a greater amount of the infective material is 
taken into the system. It is said that the digestive juices of 
the stomach are capable of destroying these organisms, but it is 
evident that a great many of them do not come in contact with 
the gastric juice, and therefore escape its destructive action. 
The second mode of infection is what is known as the exter¬ 
nal or cutaneous , and here is where flies, especially the blood¬ 
sucking varieties, when in large numbers, play an important 
part in the spread of charbon. There is an erroneous impres¬ 
sion that there is a special charbon fly. This is not so. Any fly 
may be a charbon fly, so-called, when the disease is in existence, 
because after sucking the blood of a charbonous animal—which 
contains myriads of the germs—it simply transmits the disease 
to the previously healthy animal by inoculation. Death from 
this mode is not generally so rapid, because the amount of in¬ 
fection is not so great, and the multiplication of the organisms 
necessarily not so extensive until the later stages, when the • 
whole system is engorged with them. 
The third mode is by way of the respiratory apparatus, 
inhaling the spores in a dried or desiccated condition, and mixed ; 
with the atmospheric air. This is the most uncommon method. 
