It uniformly happens, however, that, in many instances, where the action of the bark would be most beneficial, it is impossible to induce it, owing to several causes, but particularly to its effect on the stomach; for, in many instances, it produces sickness, or nausea, in which case it can do no good, and ought to be abandoned. Momentary sickness, after taking a dose of bark, is indeed a very general effect, and does not materially injure its operation; but, whenever it is either frequently vomited, or produces a sickness of considerable duration, it must either be given in smaller quantities, or in a different form, or at longer intervals; or if all of these fail, it must be laid aside completely, because it not only cannot produce its specific effect, but will even injure the remaining powers by its effect upon the stomach. The best form in which bark can be prescribed is that of powder, which is more effectual than any tincture, or the extracts. This ought to be exhibited in as great quantity as the stomach will bear, which cannot be reduced to any certain scale. In general, an adult ought, if possible, to take half a drachm, or two scruples, every forty minutes, in the most palatable vehicle; for much depends upon the taste, owing to the sympathy betwixt the mouth and the stomach; and, for this reason, the same vehicle ought seldom to be used more than twice in immediate succession; because, by changing the vehicle, we not only change the taste, which has a tendency to prevent loathing, but also modify the immediate action on the stomach, changing, to a certain degree, the former impression, which was perhaps beginning to produce sickness. Lemon juice and water, the different kinds of wines, punch, pimento, cinnamon, and peppermint waters, milk, rose water, beer, &c. afford us a variation which may be usefully employed. The tincture and watery infusion of the bark, either separately or mixed together, are frequently employed, when the powder is vomited; but, as they must be given in very considerable quantities, in order to produce any good effect, they are very apt to produce sickness, and are likewise so inferior in power to the powder, that they are very little to be trusted. The extract with resin, is a better form than the tincture, or infusion; and, where the powder is rejected, may be made into pills. When the stomach rejects every form and preparation, it has been proposed to give the bark in clysters, and this ought certainly to be done rather than lose the effects of the remedy; but, given in this way, its effects are more uncertain. From two drachms to half an ounce of the powder of bark, may be diffused in three ounces of soup, or mucilage, with fifteen or twenty drops of laudanum, and given as an enema. This must be repeated at least every hour and a half, or two hours, until the stomach can retain the medicine.