The Sense of Smell 



Is he apprised of the contents of the soil by 

 a general emanation, the fungous effluvium 

 common to the different species? In that 

 case an extremely embarrassing question 

 arises. 



I paid some attention to the ordinary mush- 

 rooms, many of which, as yet invisible, an- 

 nounced their coming as imminent by crack- 

 ing the surface of the ground. Now I never 

 saw the Dog stop at any of those points 

 where my eyes divined the cryptogam push- 

 ing back the earth with the thrust of its cap, 

 points where the ordinary fungous smell was 

 certainly most pronounced. He passed them 

 by scornfully, with not a sniff, with not a 

 stroke of his paw. And yet the thing was 

 underground; and its reek was similar to 

 others which he sometimes pointed out to us. 



I came back from the Dog's school with 

 the conviction that the truffle-detecting nose 

 has a better guide than smell, in the sense in 

 which our olfactory powers 'realize it. It 

 must perceive, in addition, effluvia of a dif- 

 ferent order, full of mystery to us, who are 

 not equipped accordingly. Light has its dark 

 rays, which are without effect upon our retinae, 

 but not apparently upon all. Why should not 



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