Various rules are given for their preparation. In this country and England, the officinal tinctures are made in the proportion of 1 troy ounce of drug to 8 fluid ounces of tincture. In Germany and France the proportion is 1 part of the drug to either 5 or 10 parts of the menstruum. For the carbonator's purpose different strengths are prepared.

Fig. 408.   Tincture Press

Fig. 408. - Tincture Press.

Fig. 409.   Squire's Infusion Pot

Fig. 409. - Squire's Infusion Pot.

Preparation

Tinctures are best prepared by maceration. The manipulation must vary with the nature of the drug, the time being from 2 to 8 days. A certain amount of alcohol will be retained in the powder and is regained like that from exhausted percolates. In some cases the retained menstruum is expressed by a so-called tincture press, but regaining it by distillation is preferable.

The drugs to be macerated must be coarsely powdered or cut into thin slices.

Preservation

"All tinctures should be perfect solutions, and to retain them entirely transparent the evaporation of the volatile portions should be prevented. Tinctures are best kept in well-stoppered bottles, in a room where the temperature is not subject to great variations, and where they are not exposed to the direct sunlight. The size of the bottles should be adapted to the quantities of the tincture that are likely to be used within a reasonable length of time". - N. D.