would that spring lay more than one. I will endeav- 

 our to get a hen, and examine her. 



Your supposition that there may be some natural 

 obstruction in singing birds while they are mute, 

 and that when this is removed the song recom- 

 mences, is new and bold : I wish you could discover 

 some good grounds for this suspicion. 



I was glad you were pleased v/ith my specimen 

 of the caprimulgus , or fern-owl ; you were, I find, ac- 

 quainted with the bird before. 



When we meet, 1 shall be glad to have some con- 

 versation 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 col- 

 lect in many years would go into a very narrow 

 compass. 



Some extracts from your ingenious *' Investiga- 

 tions of the difference between the present tempera- 

 ture of the air in Italy," &c. have fallen in my way ; 

 and gave me great satisfaction ; they have removed 

 the objections that always arose in my mind when- 



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