54 The Lung Plague of Cattle. 



currence of cough ten to fifteen days after inoculation, 

 yet among the multitudes of inoculated beasts, there has 

 been no evidence of extensive disease of the lungs that 

 can be demonstrated to have been of this nature. The 

 local changes in the seat of inoculation are like those met 

 with in the lungs in the ordinary forms of the disease, al- 

 lowance being made for the natural differences of struct-' 

 ure, and that they are specific is sufficiently evidenced by 

 the now almost universal acceptance of the prophylactic 

 value of inoculation. The conveyance of the disease 

 from an inoculated animal is by no means unknown. 

 We have seen instances in which the plague appeared 

 to start in a stable from inoculated animals, and a very 

 striking instance is recorded by Eeynal in which an 

 inoculated Brittany cow conveyed the affection to two 

 others that stood beside her in the stable of the Alfort 

 School. There is therefore every reason to believe that 

 the contagium propagates itself in whatever tissue of a 

 susceptible animal it may be lodged and that there the 

 morbid processes are localized. 



Prevention. 



Under this head we take up that phase of the affection 

 which is vital to the interests of America. That this 

 plague is an exotic all history testifies. That animals 

 susceptible to its contagium (buifalos) have existed in 

 America for immemorial ages without a single instance 

 of the spontaneous generation of the pestilence, is un- 

 questionable. That any such spontaneous generation of 

 the contagium would have been propagated and perpetu- 

 ated in the widely wandering herds of buffalo as it has 

 in the Old World steppes, the South African ranges and 

 the Australian plains, is indisputable. That this Old 

 World contagion can be crushed out of the New World 

 States and driven back to its ancient haunts in Europe 

 and Asia, and its more recently conquered territory in 

 Africa and Australasia, is equally certain. 



