Vomiting, or the act of ejecting the contents of the stomach, is frequently mentioned in this work as a symptom of different diseases, affecting different organs. The same remark applies to retching, which may be defined to be ineffectual, or painful contractile efforts to expel the contents of the stomach, either when the stomach is full, or when it is empty.

Vomiting is a prominent symptom in all the disorders of the stomach, and in those of the alimentary canal and its appendages.

The vomited matter may consist of mucus, or of bile, or of blood, or of food. Indigestible food, or any substance calculated to injure the stomach, is expelled by vomiting; or at least attempts are made for that purpose.

Vomiting is effected by the anti-peristaltic action of the stomach itself, aided by the contraction of the abdominal muscles, and it is favoured by a moderately-distended state of the stomach.

The induction of vomiting may be necessary where injurious substances, indigestible food, or poisons, have gained access into the stomach; and when the stomach is over-loaded with food. Dogs instinctively eat the "dog-grass" when they have gorged themselves.

The medicinal agents which have the property of inducing vomiting, are termed emetics. For the cases just mentioned a small tumblerful of lukewarm water is the best - harmless in itself, and sufficient to wash out the stomach thoroughly. The addition of a teaspoonful of salt, or of an egg-spoonful of mustard, gives greater emetic power. Tartar emetic is a dangerous drug to dogs; but lest this should be thought a prejudiced opinion, let us hear what Professor Gamgee says: - " As dogs are easily acted on by emetics, they are frequently dosed with them, and I have seen many cases of death from exhaustion, diarrhoea, or dysen-try, especially in cases of distemper, from abuse in the employment of drugs given with a view to unload the stomach."

Vomiting as a symptom of disease will subside when the disease on which it depends is cured.