30 THE DISEASES OP THE DOG. 



large number of sheep may be injured by one dog in a very 

 short time. It has been supposed that sound dogs mani- 

 fest an instinctive aversion to rabid ones, but such is not 

 the case, as has been amply proved. The unfortunate 

 tendency of mad dogs to travel great distances, especially 

 during the night, has much increased the belief in the 

 spontaneous origin of this disease ; the animal which 

 brought it into the neighbourhood having passed through 

 and done the mischief unobserved. Numerous cases of 

 this kind are on record where very strict inquiries have 

 proved instances of supposed spontaneity to be, really, 

 unobserved inoculation. The mad dog is characterised 

 by his contempt for threats and his fearlessness ; this is 

 partly due to perverted or lost sensation and partly to 

 mental perversion, which latter seems in some cases in the 

 dog, as in hydrophobic men, associated with a remarkable 

 degree of self-restraint, so that the hand will be seized 

 with apparent fury, but freed without infliction of a wound 

 after being retained in the mouth and champed for a little 

 while. The question of whether or no this mental aversion 

 extends to the fear of water in the dog and the superven- 

 tion of paroxysms at the sound of falling water, as in man, 

 has been much discussed, because it was thought that the 

 fear of water would be a sound and easily applied test for 

 diagnosis of rabies in the dog. Suffice it to say that it 

 has been amply established that this is not a pathogno- 

 monic symptom, and is altogether insufficient as a test. 

 The rabid animal will approach water freely and drink 

 when not prevented by spasm of the throat or the loss of 

 swallowing power seen in the latter stages ; even then, 

 however, he will endeavour to slake his almost insatiable 

 thirst. The mouth becomes very dry and of a dark 

 purple colour after the disease has been present for some 

 time, and in the " dumb " form the lower jaw drops and 

 the throat is swollen (a symptom which disappears at 

 death). Occasionally the whole head is oedematous, gene- 

 rally the tongue is pendulous, it often has been injured, 

 and the teeth, especially the canines, may have been broken 

 by the furious attempts of the animal to escape from con- 



