296 WING-CLAPPING 



dozen birds to an immense height, not circHng up- 

 wards, but climbing the air like a skylark, until it 

 is so far up as to appear like a floating black speck 

 in the sky. At that great altitude it will remain 

 hovering for an hour, uttering its various vocal 

 sounds, the birds keeping a yard or so apart; but 

 at intervals they close in a bunch and with their 

 wings strike resounding blows on the wings of those 

 nearest to them, and even when the birds are no 

 longer visible the sound is heard like hand-clappings 

 in the sky. 



The best example of wing-clapping is that of our 

 common nightjar, and is most interesting in localities 

 where the bird is abundant, when half a dozen to 

 a dozen or more meet of an evening to wheel about 

 like a company of playful swallows — a sort of wild 

 aerial dance with the accompaniment of various 

 strange cries and wing-clappings. Doubtless long 

 practice has greatly modified the structure of the 

 wing joints, so that the bird is able to smite his wings 

 together over his back with such violence as to produce 

 a sound as loud as a hand-clap. 



It is a very rough and primitive sort of music, 

 but in the snipe — the "goat of heaven" — the 

 feathers have been modified to produce a more 

 elaborate kind of music — a filing or scraping sound 

 in some species and a tremulous bleating sound 

 in others. These are so like vocal sounds that 

 one does not wonder that the controversy as to 

 whether they were vocal or instrumental lasted 

 quite a hundred years in England. 



