of those beings with whom I can be little acquainted 

 in their natural state. Not long since I spent a fort- 

 night at the house of a friend where there was such a 

 vivarium, to which I paid no small attention, taking 

 every occasion to remark what passed within its 

 narrow limits. It was here that 1 first observed the 

 manner in which fishes die. i\s soon as the creature 

 sickens, the head sinks lower and lower, and it stands 

 as it were on its head ; till, getting weaker, and los- 

 ing all poise, the tail turns over, and at last it floats 

 on the surface of the water with its belly uppermost. 

 The reason why fishes, when dead, swim in that 

 manner is very obvious ; because, when the body is 

 no longer balanced by the fins of the belly, the broad 

 muscular back preponderates -by its own gravity, 

 and turns the belly uppermost, as lighter from its 

 being a cavity, and because it contains the swimming- 

 bladders, which contribute to render it buoyant. 

 Some that delight in gold and silver fishes have 

 adopted a notion that they need no aliment. True it 

 is that they will subsist for a long time without any 

 apparent food but what they can collect from pure 

 water frequently changed ; yet they must draw some 

 support from animalcula, and other nourishments 

 supplied by the water ; because, though they seem to 

 eat nothing, yet the consequences of eating often 

 drop from them. That they are best pleased with 

 such jejune diet may easily be confuted, since if you 

 toss them crumbs they will seize them with great 



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