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. Tt 

 must perceive, in addition, effluvia of a" dif- 

 ferent order, full of mystery to us, who are 

 not equipped accordingly. _Lighthas its dark 

 j-ays, which are without effect upon our retinae, 



but not apparently upon all. Why should not 

 - rr J . . f_ , .... ... ^-\ ^ ^~^_^ 



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