258 THE NATURAL HISTORY 



LETTER LIV 



Dear Sib, 



When I happen to visit a family where gold and 

 silver fishes are kept in a glass bowl, I am always pleased 

 with the occurrence, because it offers me an opportunity 

 of observing the actions and propensities of those beings 

 with whom we can be little acquainted in their natural 

 state. Not long since I spent a fortnight at the house of 

 a friend where there was such a vivary, to which I paid 

 no small attention, taking every occasion to remark what 

 passed within its narrow limits. It was here that I first 

 observed the manner in which fishes die. As soon as 

 the creature sickens, the head sinks lower and lower, and 

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

 losing 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 Ihey 

 can collect from pure water frequently changed ; yet Ihey 

 must draw some support from animalcula, and olher 

 nourishment 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 



