174 NATURAL HISTORY 
LETTER X. 
Selborne, Aug. 1, 1771. 
DEAR “sa ee what follows, it will 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 be- 
low 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 G flat or F sharp, in B 
flat, and A flat. He heard two hooting to each 
other, the one in A flat, and the other in B flat. 
Query: Do these different notes proceed from dif- 
ferent 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 in D, and the other in 
D flat, which made a disagreeable concert: he 
afterward heard one in D sharp, and about Wolmer 
Forest some in C. As to nightingales, he says 
that their notes are so short and their transitions so 
rapid that he cannot well ascertain their key. 
Perhaps in a cage and in a room their notes may 
be more distinguishable. This person has tried to 
settle the notes of a swift, and of several other 
small birds, but cannot bring them to any criterion. 
AsI have often remarked that redwings are some 
