142 NOTES OP OWLS AND OTJCKOOS. 



tion, these birds can make the shafts of their long feathers 

 clatter Kke the swords of a sword-dancer ; they then trample 

 very quick with their feet, and run backwards towards the 

 females. 



I should tell you that I have got an uncommon calculus 

 (sgogropila, taken out of the stomach of a fat ox. It is 

 perfectly round, and about the size of a large Seville orange ; 

 such are, I think, usually flat. 



LETTER XLV. 



TO THE HOIT. DAINES BAEEINGTON. 



Selborne, Aug. 1, 1771. 

 Deae Sie, — Erom what follows, it wOl appear that neither 

 owls nor cuckoos keep to one note. A friend remarks that 

 many (most) of his owls hoot in B flat ; but that one went 

 almost half a note below A. The pipe he tried their notes 

 by was a common half-crown pitch-pipe, such as masters use 

 for tuning of harpsichords ; it was the common London 

 pitch. 



A neighbour of mine, who is said to have a nice ear, 

 remarks that the owls about this village hoot in three 

 different keys, in Gr flat or E sharp, in B flat, and A flat. 

 He heard two hooting to each other, the one ia A flat, and 

 the other in B flat. Query : Do these different notes pro- 

 ceed from difierent species, or only from various individuals ? 

 The same person finds, upon trial, that the note of the 

 cuckoo (of which we have but one species,) varies in different 

 individuals ; for, about Selborne wood, he found they were 

 mostly in D ; he heard two sing together, the one ia D, and 

 the other in D sharp, which made a disagreeable concert ; 

 he afterwards heard one ia D sharp, and about Wolmer 

 Eorest, some in C. As to nightiagales, he says, that their 

 notes are so short, and their transitions so rapid, that he 

 cannot well ascertain their key. Perhaps ia a cage, and 

 ia a room, their notes may be more distinguishable. This 

 person has tried to settle the notes of a swift, and of 



