﻿60 FIELD AND FORKS!. 



the same parts in other — non-drumming — members of the Grouse 

 family testifies. Much more, then, we think would the Ruffed Grouse 

 be unable to produce, with a comparatively slow motion of its wings 

 through the air, (i. e. in the same way in which it is claimed the bird 

 makes the first sounds of its drumming,) any relatively louder sound 

 than the Humming-bird. 



We think that, while Mr. Henshaw has approached nearest to a 

 solution of the question under discussion, he has misconceived the un- 

 derlying principle, and followed predecessors who have treated the 

 subject in such a superficial manner as leads one to believe that they 

 never doubted their ability to substantiate their statements. One as- 

 serts that a bird's wing brought in forcible contact with its body, 

 may produce a sound to be heard at the distance of a quarter of a 

 mile or more. He thinks not of the physical impossibility of such a 

 result. The truth is, the subject has not been grasped in its full ex- 

 tent. Observers relate their experience and draw their conclusions 

 without considering whether or not they militate against anterior nat- 

 tural laws. They tell us the manner of producing the sound, but do 

 not attempt to expain the cause of it. 



Evidently there is some connection between the air and the sound. 

 Of course the primary cause is the vibration of the wings and the im- 

 mediate result of this vibration, as we understand it, is the compress- 

 ing of air between the wings and body — first by a slow movement that 

 causes the regularly interrupted "beats" with which the sound begins, 

 and then with such accelerating motion as to cause the sounds to run 

 into each other, and to terminate in a rolling noise resembling dis- 

 tant thunder. The compressed air, escaping from under the wings, 

 causes the "drumming," just as, when applauding a well-acted scene 

 in a play, the more demonstrative of us, bringing our concaved hands 

 forcibly together, cause the inclosed air to escape wtih a report. 



We do not hesitate to confess our inability to follow up the course 

 which the subject has taken under present treatment, but hope that 

 our suggestions may interest a more competant hand in it ; and that 

 we shall, ere long, know — how the Pheasant drums, why he drums, 

 and the physical cause of the sound he makes in drumming. 



David Scott. 

 Washington, D. C, August, 1876. 



