Which is best effected by an infusion of Tobacco. See _Tabaci Folia_. 3. _To produce Astringent and Anodyne, or Carminative effects._ Common starch, with the addition of Tincture of Opium, is the most common and convenient form for this purpose. See also _Assafœtida_, _Terebinthinæ Oleum_, and _Formulæ 8, 9, 29, 30_. In some cases the injection of _cold water_ acts as a powerful astringent, and from its impression upon the rectum, will frequently afford instantaneous relief in the piles. 4. _To destroy Ascarides._ See _Form. 164_. 5. _To act as an emollient fomentation._ 6. _To convey nutriment._ In the administration of Clysters, for the fulfilment of any of the last five indications, it is obvious, that the stimulus of distention should be avoided, as being incompatible with our object; the quantity, or bulk of the solution, ought to be also carefully graduated; to prevent, for example, the opiate clyster from being too soon returned, Dr. Cullen has remarked that it seldom should be made of more bulk than that of three or four ounces of liquid, and this also of a very mild kind. In administering a bitter decoction for the cure of Ascarides, the same precaution is necessary, or the gut will suddenly contract and expel the clyster, which always acts with more certainty when allowed to remain for some time. The proportions of fluid vehicle necessary for the different stages of life, under ordinary circumstances, may be stated as follows:—An infant at its birth, or soon after, requires about one _fluid ounce_; a child between the age of one and five years, from three to four _fluid ounces_; a youth of ten or fifteen, from six to eight _fluid ounces_; and an adult may take twelve. With regard to the dose of the active ingredient of a _Lavement_, it may be estimated as triple of that taken by the mouth. INJECTIONES. Under this head may be comprehended the various medicinal preparations which are employed as local applications;—to the urethra for the cure of gonorrhæa, and to the vagina for that of the different discharges to which females are liable. With respect to the former of these it has been truly observed, that “among the whole class of remedies employed for surgical purposes, there is scarcely one which has occasioned a greater diversity of opinion;” to enter however into an examination of this subject would be entirely foreign to the intention of the present work; it is only necessary to state, that for their preparation the same principles of combination, and the same chemical precautions, apply, as have been already investigated under the head _Misturæ_. In some cases the practitioner will find it useful to insure the entire solution of his active ingredient; while in others, the presence of a precipitate may enhance the efficacy of the application, as illustrated by _Form. 62_.