^\ut 'hatch 



LETTER LVI. 



To the same. 



HEY who write on natural history cannot too 

 frequently advert to instinct, that wonderful 

 limited faculty, which, in some instances, 

 raises the brute creation as it were, above 

 reason, and in others leaves them so far 

 below it. Philosophers have defined instinct 

 to be that secret influence by which every 

 species is impelled naturally to pursue, at all times, the same 

 way or track, without any teaching or example; whereas 

 reason, without instruction, would often vary and do that 

 by many methods which instinct effects by one alone. Now 

 this maxim must be taken in a qualified sense; for there 

 are instances in which instinct does vary and conform to the 

 circumstances of place and convenience. 



It has been remarked that every species of bird has a mode 



