The latter is one of the most certain means we possess of emptying the stomach; and by means of it this viscus may be washed out, and the antidote, if any be known, administered. In speaking hereafter, however, of the treatment to be adopted in each particular instance it will be seen that there are some cases, as poisoning by corrosives, in which this instrument cannot be used; as it might not only cause laceration of the tissues, but even perforation of the œsophagus or stomach. It is hardly necessary to mention that in all cases a certain tact is required in its employment; the tube having, on more than one occasion, been introduced into the trachea, and the lungs injected with water, &c. It is a good rule also to withdraw less fluid than is pumped into the stomach. Supposing, however, that this instrument is not at hand, or that it is an improper occasion for its employment, recourse must be had to vomiting, natural or artificial. Vomiting is, in many instances, one of the first and most important signs of poisoning, especially by irritant substances. When such is the case, it is only necessary to foster the tendency by copious draughts of lukewarm water; but if there be no vomiting and the stomach pump be not at hand an emetic must be given. Of these remedies perhaps there is not one which can be generally used with so much advantage as the sulphate of zinc in scruple doses; for not only is it more rapid in its action, but its effects are less depressing than those of any others. This last recommendation will appear the more desirable when we remember that the absorption of poisons is promoted by all lowering measures; and consequently, bleeding, the exhibition of tartarised antimony, and the administration of drastic purgatives, ought to be avoided. In poisoning by opium and other narcotics, the sulphate of copper in eight or ten grain doses will often excite the stomach to act when other emetics have failed. Ipecacuan wine (six or eight drachms) is a useful agent in many cases; or if a warm stimulating draught be needed a scruple of powdered ipecacuanha, with the same quantity of the sesquicarbonate of ammonia, may be administered in a wineglassful of water. In the absence of these, mustard proves an excellent substitute; a teaspoonful or two being given in warm water, and frequently repeated. Even common salt may be used with good effect. Vomiting may also be excited by tickling the fauces, as well as by the free administration of warm water or of hot greasy water. _When the poison has been applied locally_, to prevent its absorption, a ligature must be applied between the trunk and the wounded part, as near the latter as possible; while the deleterious substance is to be removed by free incisions and plentiful washings. Sucking by the mouth or by cupping-glasses may also be employed.