302 SALMON KEPT BACK BY POLLUTIONS. 



We will now apply our theory of smell in the salmon 

 to practice. Doubtless, to the fish, each river has got its 

 own smell ; taste or flavour it has hitherto been called, 

 but this, I think, is a wrong expression, as a salmon's 

 tongue has hooks upon it and is not so sensitive as the 

 tongue of land animals ; in fact, it is more an organ of 

 prehension than of taste. When the salmon is coming 

 in from the sea he smells about till he scents the water 

 of his own river. This guides him in the right direc- 

 tion, and he has only to follow up the scent, in other 

 words, to "follow his nose," to get up into fresh water, 

 i.e., if he is in a travelling humour. Thus a salmon 

 coming up from the sea into the Bristol Channel would 

 get a smell of water meeting him. " I am a Wye sal- 

 mon," he would say to himself. " This is not the Wye 

 water : it's the wrong tap, it's the Usk. I must go a 

 few miles farther on," and he gets up steam again. 



We may learn another useful lesson from the presence 

 of the power of smell in a salmon. I feel more and more 

 certain every day that purity of water is the principal 

 element of a good salmon fishery; if, therefore, stinking 

 water is allowed to go into the river, the fish will per- 

 ceive the fact when he may be possibly miles down the 

 river. A foxhound can smell the scent of a fox on the 

 ground, even although the fox might have passed over 

 the ground a considerable time before. We ourselves 

 can smell weeds or turf burning in fields at a very great 

 distance ; just so the salmon may receive cognisance of 

 a town sewer, or tar water, or the dirty water from sheep 

 washing, for a long distance down the river. His in- 

 stinct will teach him that there is danger ahead, and he 

 is very likely to fall back again, and small blame to him. 

 Net fisherman should take particular notice of this 

 argument ; it is of commercial interest to them. 



