Viola. Violet. (Not officinal.) The recent petals of Viola odorata, the Sweet Violet; Lin. Syst., Pentandria monogynia: indigenous.

Description. Small petals, having a very agreeable characteristic odour and colour. The root has been used as a medicine.

Prop. & Comp. The infusion, which is not strongly coloured, becomes bright red on the addition of an acid, and green with an alkali, and hence employed as a test. Besides the above colouring matter, the petals contain a volatile oil and a little acrid matter, violine, which can be separated as a white powder, and somewhat resembles emetina.

Prep. Syrupus Violae, Lond., 1851. Syrup of Violet.

(Violets, nine ounces; boiling distilled water, one pint; sugar, three pounds, or as much as may be necessary; rectified spirit, two fluid ounces and a half, or as much as necessary. Macerate the violet flowers in water for twelve hours, then press and strain. Set aside that the dregs may subside, and complete the process as directed for syrup of marsh-mallow.)

Therapeutics. Violets are used in medicine for their colour, and on account of the slight laxative effect of the syrup, which is given to very young children, either alone, or mixed with almond oil. The root is purgative, and emetic in half-drachm or drachm doses.

Dose. Of syrupus violae, 1/2 drm. to 2 drm.

Adulteration. Sometimes the petals of the scentless species are substituted for those of the sweet violet; of little therapeutic importance.