1. On Nervous System.—Giddiness, numbness, and tingling in the limbs is a primary effect, followed by gradually increasing paralysis of the muscles, and insensibility of the surface of the body to pinching and pricking. Dr. Fleming asserts that it produces a powerful sedative effect on the nervous system. At any rate, it now seems to be proved that aconite paralyses the sensory nerves, commencing at their peripheral endings.
2. On Vascular System.—Extreme depression of the circulation is produced by doses large enough to cause death. The pulse may become imperceptible at the wrist. In medicinal doses, aconite lowers the heart‘s action; in poisonous doses, it causes fatal syncope.
3. On Digestive System.—Some have denied the irritant action of aconite on the alimentary canal, but Sir R. Christison states that he was deterred from the use of aconite “by two patients being attacked with severe vomiting, griping, and diarrhœa.”
CHAPTER XII
CEREBRAL POISONS
The symptom most characteristic of these poisons is the marked anæsthesia which they produce when their vapours are inhaled. The hydrate of chloral, though placed under the above heading, is more closely allied in its action to opium than to ether or chloroform.
ETHER
Ether, when taken in its liquid form, produces symptoms and post-mortem appearances not unlike those caused by alcohol.
Fatal Dose.—No death having been recorded, the fatal dose of this substance is unknown.
Ether Vapour.—The vapour of ether has caused death. Entering the blood through the lungs, it acts with great rapidity, a state of lethargy being quickly induced.