THE HABITS OF FISH. 49 



them in a very different light. Trout, and such 

 like entomological destroyers, rise at flies as food ; 

 but there are many times when they also throw 

 themselves high out of the water, in mere wanton- 

 ness ; and this may be particularly remarked in 

 the cool of an evening following a very hot day, 

 at which time whipping for them is next to use- 

 less. I am at a loss to account for these feats. 

 My conjectures are, that on such days fish have 

 lain, as it were, dormant for some time, and 

 mostly low in the water, to effect which their air 

 bladders have been continuously much com- 

 pressed by low respiration, and have become 

 comparatively empty ; and there is something in 

 their sudden rise to the surface analogous to the 

 elevation of body, and accompanying deep sigh, 

 wherewith we bipeds relieve our lungs after a 

 long, serious, careful thought. Then again, the 

 water, from the heat of the day, has emitted 

 more than its due proportion of air wholesome to 

 fish ; and that which they pass through their gills 

 has become unpleasant to them, and they are glad 

 for a moment to imbibe a portion of cooler inspi- 

 ration, in another element, to supply artificially 

 their natural wants. The water, too, as Captain 

 Williamson, in his "Vade Mecum," says, is at 

 such times of higher temperature than the air ; 

 whence the latter becomes to them a refreshing 

 bath. Roach, barbel, carp, and other fish, often 



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