288 NATURAL HISTORY 



this district, might be found there, in different secret doi 

 mitories; and that, so far from withdrawing into warmer 

 climes, it would appear that they never depart 300 yards 

 from the village. 



LETTER LYI. 



TO THE HONOURABLE DAINES BARRINGTON. 



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 in- 

 stinct 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 of nidification peculiar to itself; so that a schoolboy 

 would at once pronounce on the sort of nest before him. 

 This is the case among fields and woods and wilds ; but in 

 the villages round London, where mosses and gossamer, and 

 cotton from vegetables, are hardly to be found, the nest of 

 the chaffinch has not that elegant, finished appearance, nor 

 is it so beautifully studded with lichens, as in a more rural 

 district ; and the wren is obliged to construct its house 

 with straws and dry grasses, which do not give it that 

 rotundity and compactness so remarkable in the edifices of 

 that little architect. 1 Again, the regular nest of the house 



1 May not the use of bright and fresh materials in the country, and 



