How Animals Talk 



elastic hoofs, and that our pigs respond not only 

 to vibration of earth or air, but also to some finer 

 vibration set in motion, apparently, by human 

 excitement. 



Moreover, I have known one dog, old and 

 half deaf, that, whether asleep or awake, would 

 respond to the faint tremor of his master's au- 

 tomobile before it came into sight or hearing. 

 And what there is in the tremor of one machine 

 to distinguish it from another of the same make 

 and power is something that the unaided ear can 

 hardly measure. The dog lived under a hilltop, 

 on a highway over which scores of automobiles 

 passed daily; and on holidays, when his master 

 was at home, the scores would increase to hun- 

 dreds. He would sleep for hours on the veranda, 

 paying no heed to the noise or smell or dust of the 

 outrageous things, till suddenly he would jump 

 up, bark, and start for the gate; and in a moment 

 or two we would see the master's auto rise into 

 sight over the brow of the hill. 



The instant response of deer or dog to minute 

 external impressions, though startling enough, is 

 probably wholly physical, a matter of vibrations 

 on one side and of nerves on the other; but there 

 are other phenomena of sensitiveness (and these 

 bring us nearer to our trail of animal communica- 



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