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 The True Function of Stimulants.—One whose heart has nearly given out because of exposure to severe weather may be temporarily revived by alcohol. It will not be wise to do so unless it is certain that a warm fire and protection will be reached before the reaction comes. Much less would be necessary to revive an abstainer than a drunkard. Habitually disturbing the body with stimulants makes them ineffective in a time of emergency. A cup of coffee will not keep a watcher awake if he is used to coffee. Definitions: Stimulant, Narcotic, Poison.—A stimulant is anything that excites the body to activity, but is of no help or of insignificant help, in replacing the strength used up.

A narcotic is anything that deadens or dulls the nervous system. It comes from a word meaning "to benumb."

Poisons are active substances, which, taken in quantities, as man takes food, destroy life; in smaller quantities they injure the body and may destroy life. Alcohol is a poison. Wine, beer, whisky, contain varying quantities of it.

The Narcotic and Stimulant Effects of Poisons.—Examples of poisons are alcohol, nicotin, opium, arsenic, strychnin. Poisons excite the body when taken in small doses, while in large doses they produce paralysis and death. The irritating or stimulating effect is due to derangement of the functions or to the efforts of the cells to free the body of the destructive substance. The narcotic effect is due to the poison having so benumbed the nerves and injured the cells that their activities cease, or become less for a time. You readily see how the same poison can be both a stimulant and a narcotic: the stimulating effect always comes first, followed by the stupefying effect. If the dose is very small, the stimulating effect will last longer; if it is large, the narcotic effect is greater and felt more quickly. A habit of using stimulants is an invariable sign