646

Tinctures.

part III.

in the tincture are extracted, and the solvent saturated. Theingredients must be dried and reduced to a coarse powder, andthe maceration made in close vessels, and assisted by fre-quent agitation. When completely made, tinctures should notbe allowed to remain upon the ingredients, but be filteredthrough bibulous paper, and kept in this state in well corkedbottles. Parmentier * has proposed that one-half only of thespirituous menstruum be added to the ingredients at first, andafter digesting for six days this part to be poured oft', and theremainder added. In six more the whole is to be strongly ex-pressed, and the two portions of tincture mixed together.By this method he imagines more of the active principles ofthe ingredients are extracted, and the tinctures obtained of amore uniform strength.

Tinctures are not of very extensive use as remedies, exceptin cases where stimulants are indicated; the solvent, even indoses of a few fluid drachms, often acting more powerfully onthe living system than the principles it holds in solution. Inordinary cases this action, when continued lor some time, pro-duces the same deleterious effects as the habitual use of ardentspirits; and often lays the foundation of the pernicious customof dram-drinking. When the action of a substance is the re-verse of stimulant, it cannot with propriety be exhibited inthis form, unless the dose be so small that the operation ofthe spirit cannot be taken into account, as in tincture of fox-glove. The chief use of this class of preparations, therefore,is to enable infusions and decoctions, to which they are added,to sit lighter on the stomach, or to add to them some activeprinciple which water is incapable of extracting.

The general rule given in the London Pharmacopoeia for thepreparation of tinctures is, " to prepare them in closed vessels,and to shake them frequently during the maceration."TINCTUR A ALOES. Lond. Tincture of Aloes. »" Take of extract of spiked aloes powdered, half an ounce;extract of liquorice, an ounce and a half; water, a pint; rec-tified spirit, four fluid ounces. Macerate in a sand-bath untilthe extracts are dissolved; then strain."

Dublin.u Take of socotorine aloes in powder, half an ounce ; ex-tract of liquorice dissolved in eight ounces of boiling water,an ounce and a half; proof spirit, eight fuid ounces. Digestfor seven days; then strain."

Tinctura Aloes SocoTORiNiE. Edin. Tincture of Soco-torine Aloes.

» Annates de Chirme, lxii. 40. ' Teinture d'Alo^s (F.) Tintura J'Aloe {/.)