Class IL SWALLOWS. 415 



when we know that the otter *, the corvorant, and 

 the grebes, foon periih, if caught under ice, or en- 

 tangled in nets : and it is well known, that thofe 

 animals will continue much longer under water than 

 any others to whom nature hath denied that par- 

 ticular ftrufture of heart, ncceflary for a long 

 refidence beneath that element. 



* Though entirely fatisfied in our own mind of the impofli- 

 bilty of thefe relations ; yet, defirous of ilrengthening our 

 opinion with fome better authority, we applied to that able 

 anatomiit, Mr. John Hunter ; who was fo obliging to inform 

 us, that he had difTefted many fwallows, but found nothing 

 in them different from other birds as to the organs of refpi- 

 ration. That all thofe animals which he had diffeaed of the 

 clafs that deep during winter, fuch as lizards, frogs, &c. 

 had a very different conformation as to thofe organs. That 

 all thefe animals, he believes, do breathe in their torpid flate; 

 and, as far as his experience reaches, he knows they do : and 

 that therefore he efteems it a very wild opinion, that terreftrial 

 animals can remain any long time under water without drown- 

 ing. 



BILL 



