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tact of the tips of the wing feathers with the outer feathers of the tail.

The first of these finds an advocate in Mr. G. H. Storer, F.Z.S. (the original propounder of the theory, I believe) who wrote in the Badminton Magazine' of June 1899

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As snipe were plentiful, I spent much time during the early summer in studying their habits, and especially in trying to satisfy myself as to the means by which the male snipe produces the 'drumming' or 'bleating' which one so frequently hears during the breeding season. soon convinced myself that the sound does not proceed from the mouth or vocal organs, as it is only produced when the bird is gliding through the air, and never, so far as my own observations have gone, when perching or at rest upon the ground. In this, I think, all observers will agree. There remain the wings and tail as possible agents in sound production. Now, if the snipe be carefully watched, it will be noticed that after he has soared to a considerable height in the air he will suddenly begin to descend, with half-closed wings and wide-spread tail, in an oblique direction towards the earth. This is the moment when the snipe beats his wonderful 'drum.' The sound does not at all suggest the 'whuz! whuz!' produced by the vibrating pinion feather of the flying swan or the 'whirr' of the startled partridge or pheasant, as their wings beat the air; neither is it made by clapping the wings back to back like the rising wood pigeon, or by striking the sides of the body after the manner of the American ruffed grouse. In fact, I do not imagine that the wings can in any way be considered

the musical instruments.

Rather is the apparatus to be

looked for in the tail. Examine the outer tail feathers of

a snipe, and you will see at once that the shaft is strong and bent like a sabre, and that the outer web is stiff and very narrow, whilst the inner web is broad. Pluck out one of these feathers and fix it upon a stick. Now move the stick quickly, so that the outer web strikes the air obliquely as did the tail of the bird in life, and you will obtain a good if not very powerful imitation of the snipe's bleat.

Mr. Storer-I am sure he will not mind criticism in connection with a subject, bird life, in our knowledge with regard to which he is so keenly interested— hits upon a hitherto unsuspected probable agent in the production of the drumming of the snipe, but in doing so he misses the essential point. There is no doubt, as Mr. Storer says so, that a good, if not very powerful imitation of the snipe's bleat,' may be obtained if the feather be mounted on a stick and the stick moved quickly and from this we may infer that if the entire tail of a snipe were dried in the spread position in which the drumming snipe holds it and were similarly mounted on a stick and the stick moved quickly through the air, an equally good imitation and a more powerful one would be afforded. But how quickly must the feather on the stick be moved through the air to produce the drumming sound, and

how quickly does the snipe stoop through the air while drumming?

Instead of swooping at high speed, the drumming snipe the personal equation again here, please-does not exceed in his pace the initial pull of gravitation (16 ft. in the first second I believe is correct) by more than three to one; otherwise the bird does not descend at a greater speed than something like 50 ft. per second. I have had no opportunity of observing a drumming snipe for nearly a year, but sitting in my chair and imagining that I see a bird in its descent, I find myself doubting whether the pull of gravitation is ever exceeded by more than two to one. Be this as it may, we will say that the swooping pace of the drumming snipe is 50 ft. per second, and in saying so we may feel pretty confident that we are over-estimating the pace. The drumming of the snipe, from the moment the bird stoops till the moment it recovers itself, lasts just about a second, under rather than over, so that, according to our estimate of speed, the dive is a dive of about 50 ft., though, as I have said, I consider 30 ft. to be the limit length of a dive.

Now let us take the first handy object-it matters not whether it is a pound weight or a pen-wiper-and hold it at arm's length, and then let it fall to the ground, fixing the speed of the fall in our minds and estimating

what treble this speed will be, viz. about 50 ft. per second. After this, let us try what sound can be aroused by moving the feather on the stick through the air at our estimated 50 ft. per second velocity. None; we must multiply 50 ft. per second several times before we can extract even a faint sound from the passage of the feather through the air. Thus we find that if the tail feathers of the snipe play a part in the production of the drumming they do not do so by their simple passage through the air as the snipe dives, and we are compelled to abandon the theory that the sound might be created by the tilt of the bird's frame during the swoop, that is, by vibrations set up by wings and tail, or one or the other, as a consequence of their resistance to the air when held at a certain angle to the line of descent.'

Next we come to the theory that the drumming may be produced by wing action, that is by vibrations aroused by the play of the wings against the air.' The speed of the swoop of a drumming snipe does not in any way affect this question: the question hangs alone upon the speed of the beating action of the wings, the angles at which the bones of the wings are held relatively to the axis of the plane of the bird's body, and the angles at which the tips of the wing feathers are driven backwards and forwards through

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the air. Let us call the bumble-bee as a witness in the question of speed. The hum evoked by the bumble-bee's wings is no greater when the insect passes swiftly by us than when it hangs almost motionless above a flower; the passage of its body through the air has nothing to do with the production of the humming. From the opposite side; rapid wing-beats do not necessarily imply velocity or even progress. The humming-bird and the hawk-moth are stationary while beating their wings at enormous speed; the kestrel beats his wings rapidly and does not move an inch, and the sparrow beats his yet more rapidly while hovering for a few seconds over some spot whereon he wants to light and in which danger appears to lurk. From all these witnesses together we find that the drumming snipe may beat his wings at very high speed without increasing his gravitational velocity by more than the ratio of the energy exerted by the humming-bird, the hawk-moth, the kestrel, and the sparrow, to counterpoise the pull of gravitation ; if the practically stationary bumble-bee can produce his loud humming while only counterbalancing the pull of gravitation, 16 ft. per second, the snipe can, if he knows how, produce a buzzing when swooping downwards without increasing his pace to more than double the pull of gravitation-that is, he can, if he

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