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76
THE POPULAR SCIENCE MONTHLY.

gentle force the resistance of the muscles, by firmly placing the hand upon its back. During the slow and measured suppression one often perceives an extremely remarkable position of the head and neck, which are left entirely free. The head remains as if held by an invisible hand in its proper place, while the neck is stretched out of proportion, and the body by degrees is pushed downward.

If the animal is left thus entirely free, it remains for a minute or so in this peculiar condition, with wide-open, staring eyes. (The lecturer here caused a hen to be brought, which he placed in this remarkable position by simply stretching out the neck and pressing down the head; the bird, having awakened, gave signs of returning to the same state when it was placed in a squatting position, without moving head or neck.) Here the actual circumstance is only the consequence of the emotion which the nerves of the skin excite, and the gentle force which overcomes the animal's resistance. Certainly, the creature a short time before had been in this condition of immobility, and might have retained some special inclination to fall back into the same, although the awakening, flight, and recapture, together with the refreshment given to the nervous system, are intermediate circumstances. Similar experiments, where the influence and effect of the pressure which is placed on the animal's muscles are manifested upon the cutaneous nerves, are best made upon small birds.

To bird-fanciers, it has been a long-known fact that one can rob gold-finches, canary-birds, etc., of the powers of their nervous systems, so that they remain motionless for a short time, by simply holding them firmly for a moment, and then letting them go.

These experiments, which I will endeavor to perform before you, are particularly striking, on account of the vivacity of the timid animals. Yet I must remind you of a possible failure, due to the unusual circumstances of noise and numbers which may have a disturbing influence on these excitable little creatures.

Here in my hand is a timid bird, just brought from market. If I place it on its back, and hold its head with my left hand, keeping it still for a few seconds, it will lie perfectly motionless after I have removed my hands, as if charmed, breathing heavily, and without making any attempt to change its position or to fly away. (Two of the birds were treated in this manner, without effect, but the third, a siskin, fell into a sleeping condition, and remained completely immovable on its back, until pushed with a glass tube, when it awoke and flew actively around the room.)

Also, in a sitting position, with the head held a little to the back, the birds fall into this sleeping condition, in spite of their open eyes; indeed, I have often noticed that the birds under these circumstances close their eyes for a few minutes, and even a quarter of an hour, and are more or less fast asleep.

I cannot omit to notice, with many thanks, that our assiduous nat-