OF SELBOENE. 151 



I will endeavour to get a hen, and to examine. 1 



Your supposition that there may be some natural obstruc- 

 tion in singing birds while they are mute, and that when 

 this is removed the song recommences, is new and bold ; I 

 wish you could discover some good grounds for this suspicion. 



I was glad you were pleased with my specimen of the 

 Caprimulgus, or fern owl ; you were, I find, acquainted with 

 the bird before. 



When we meet, I shall be glad to have some conversation 

 with you concerning the proposal you make of my drawing 

 up an account of the animals in this neighbourhood. Your 

 partiality towards my small abilities persuades you, I fear, 

 that I am able to do more than is in my power : for it is no 

 small undertaking for a man unsupported and alone to begin 

 a natural history from his own autopsia ! Though there is 

 endless room for observation in the field of nature, which is 

 boundless, yet investigation (where a man endeavours to be 

 sure of his facts) can make but slow progress ; and all that 

 one could collect in many years would go into a very narrow 

 compass. 



Some extracts from your ingenious " Investigations of 

 the Difference between the present Temperature of the Air in 

 Italy," &c., have fallen in my way; and gave me great satisfac- 

 tion : they have removed the objections that always arose in 

 my mind whenever I came to the passages which you quote. 

 Surely the judicious Virgil, when writing a didactic poem 

 for the region of Italy, could never think of describing 

 freezing rivers, unless such severity of weather pretty 

 frequently occurred ! 



P.S. Swallows appear amidst snows and frost. 2 



1 It has since been ascertained that cuckoos do lay more than one 

 egg in a season, although Dr. Baldamus, to whose remarkable essay we 

 have already referred, states that each hen bird lays but one egg in each 

 nest ; and adds that the same hen bird lays eggs of similar colouring, 

 as a general rule, in the nests of the same species only. ED. 



2 We apprehend that allusion is here made to the fact that swallows 

 which arrive early in this country occasionally get caught in late frosts, 

 and vice versa. ED. 



