bleat of a goat. For long years discussion waged furiously 

 as to the source of this sound. Some held that it was pro- 

 duced by the voice : others by the tremulous motion of the 

 wing-feathers : others, again, contended that it was caused 

 by the tail-feathers. This was first mooted by the Danish 

 naturalist, Meeves, and he produced some very striking and 

 curious evidence to prove his view. He showed that the 

 outermost tail-feathers had peculiarly thickened shafts, 

 which were also bent in a very striking way. By removing 

 these feathers, and sticking them into a cork, he was enabled, 

 by twirling the cork rapidly round at the end of a string, 

 to reproduce the " bleat " exactly. Many years later Dr. 

 Philip Bahr revived this experiment, for the purpose of finally 

 setting the matter at rest — for there were stiU many who 

 remained unconverted to the Meeves interpretation. Dr. 

 Bahr left no room for further doubt. He showed, too, that 

 during the production of this sound these tail-feathers were 

 extended laterally, so as to separate them from the rest of 

 the tail, and so give the air rushing past them during the 

 earthward plunge full play on these sound-producing struc- 

 tures. He, too, applied the test first instituted by Meeves, 

 and so clinched his arguments. One may hear this strange 

 music as early as February, and even, though rarely, as late 

 as July. But it is essentially a breeding-season, or rather 

 a " Courtship " performance sound, though it may be evoked 



56 



