Page:Proceedings of the Royal Society of London Vol 1.djvu/448

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therefore careful to relate all the circumstances. But he now finds extremely little difference in the action of the same poison, even upon different animals; and in those of the same species no difference but what may be referred to difference of quantity of poison, or age, and power of the animal. He consequently does not enter minutely into the particulars of his late experiments, but gives a general account of those which appear to be of most importance, with regard to the inferences that maybe drawn from them. The greatest part of them relate to the action of mineral poisons; but since, on the former occasion, his trials of woorara had been left imperfect for want of a sufficient quantity of that poison, he states the results of two experiments made after obtaining a fresh supply, for the purpose of endeavouring to recover animals that had been apparently killed by it.

A young cat was the subject of the first experiment. In four mi- nutes after the application of woorara to a wound in her side, she appeared to be dead, but the heart continued to act 140 times in a minute. Mr. Brodie then inflated the lungs, and repeated the artificial respiration forty times in a minute. At the end of forty minutes the pupils of the eyes were observed to contract by an increase of light upon them; but in other respects she was motionless and insensible. At the end of an hour further symptoms of life began to appear, and there was an effort to breathe occasionally. There were also various involuntary motions. The efforts to breathe became gradually more frequent, and after two hours had elapsed, the spontaneous efforts were repeated as often as twenty—two times in a minute.

The artificial respiration being then discontinued, she lay as if in a profound sleep for about forty minutes, when she suddenly awoke, and gradually recovered from all the effects of the woorara.

A second experiment, of the same kind, performed on a rabbit, was not so successful; for though the action of the heart was continued strong and regular for more than three hours by means of artificial respiration, there never was the least appearance of returning sensibility; and the pulse from that time began to subside, and ultimately ceased altogether.

The mineral poisons here examined by Mr. Brodie, are arsenic, muriate of barytes, emetic tartar, and corrosive sublimate.

When arsenic is taken internally, it is observed that some appearance of inflammation of the stomach is usually found after death; and the general opinion is, that this inflammation is caused by the local application of the arsenic to the coats of the stomach; and secondly, that this inflammation is the cause of death.

To these opinions Mr. Brodie objects, that in many cases the appearances of inflammation are too slight to warrant such an opinion; and in most instances of animals killed by arsenic, death takes place in too short time for it to be considered as the result of inflammation.

The author observes also, that the inflammation does not depend on the local application; for it has been remarked by Mr. Hunter and Mr. Hume, and Mr. Brodie has confirmed the observation by new experiments, which have satisfied him, that inflammation of the