entirely succeed, as it concerns essentially the concentration of the pigeon's attention, and the fixing of its look. Individual, inward relations, as well as outward conditions, must necessarily exercise some disturbing influence, whether the animal will give itself up to the requisite exertions of certain parts of its brain with more or less inclination, or otherwise. You then understand why apparently little circumstances may be responsible for the result of an experiment in which this critical moment plays a part.
We often see, for example, how a pigeon endeavors to escape from confinement by a quick turning of its head from side to side. In following these singular and characteristic movements of the head and neck, with the finger held before the bird, one either gains his point, or else makes the pigeon so perplexed and excited that it at last becomes quiet, so that, if it is held firmly by the body and head, it can be forced gently down upon the table. It is as Schopenhauer says of sleeping, "The brain must bite." I will also mention here, by-the-way, that a tame parrot, which I have in my house, can be placed in this sleeping condition by simply holding the finger steadily before the top of its beak.
But let me hasten, gentlemen, to say to you that, in the remarkable and singular influence which the holding of the finger exercises on pigeons, the influence of the mythical agents may not be removed; agents which may come from the organization of the experimenter, and, perhaps, spring from the outstretched finger. Nevertheless, a glass tube, a cork, a small wax-candle, or any other equally lifeless substance, placed directly on the top of the pigeon's bill, has the same magical effect as when the human finger is used. We must only be careful that the animal be placed so that its attention is fixed for some time on the object. I have seen pigeons sit motionless for some minutes, with open eyes, after I had placed a lucifer-match, or a wax-light, on the top of their bills.
Often, with hens, these experiments succeed in the most astonishing manner. I have repeatedly seized hens with both hands by the body so that their heads and necks were quite free, and forced them gently against a pedestal on which a glass tube was placed, so that it just touched the top of the bill. The animal, when left perfectly free, remained gazing fixedly at the glass tube for more than a minute. The same thing happened when a cork stopper was used, instead of the glass tube.
Finally, I will mention that with the hens I often hung a piece of twine, or a small piece of wood, directly over their crests, so that the end fell before the eyes. I mention this experiment especially, because, when performed, the hens not only remained perfectly motionless, but closed their eyes, and slept with their heads sinking until they came in contact with the table. Before falling asleep, the hens' heads can be either pressed down or raised up, and they will remain in