INTKODUCTION. 



EVERYONE is talking of the CATTLE PLAGUE ! 

 But why should we borrow this sinister and 

 gloomy denomination from the middle ages and 

 from the people's vocabulary ? Is this, then, an 

 unknown and incurable disease ? Is this the 

 first time that it has made its appearance on 

 the soil of Great Britain? To judge by the 

 manner in which the diffusion of this com- 

 plaint has been met, accounted for, explained, 

 and discussed, one might imagine it was so ; 

 and yet the mere observation of its causes, 

 its symptoms, and its signs and effects on 

 the bodies of the diseased animals, besides a 

 few references to the medical library, would 

 easily have testified that nature did not wait 

 until the second half of the 19th century to 

 generate a new distemper. No ! Nothing 

 new has appeared for a long time in the 

 worlds of space. The cosmic phenomena 

 pursue their perpetual course, and the organic 



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