Whatever may have been the remote cause, the immediate one is some irritation of the nervous system, causing convulsions, or an effusion to the head, inducing coma.

Cold, when applied in excess to the body, drives the blood from the surface to the centre, reduces the pulse, makes the breathing hard and difficult, produces coma, and, if long continued, death.

I hypnotized the girl Fanny, and when she opened her eyes in the hypnotic state the doctor made the usual tests for coma, exposing the eyes to the sudden glare of a brilliant light, sticking pins into her flesh, and so forth, and pronounced the coma absolute when, as he stuck a pin in her arm, she spoke, saying, "I wouldn't do that, it might hurt Fanny!"

"I've never seen coma in such a case last so long.