VART II.

Materia Medica.

253

of gout and rheumatism, and to restore vigour to joints aftersprains. When put into a carious tooth, it lulls the pain oftooth-ach ; and we have seen much benefit derived from rub-bing it on the temples, in defective vision from a weakenedstate of the eyes. The dose is three or four drops on a lump ofsugar.

MELISSA. Spec. Plant. Willd. iii. 146.CU 14. Ord. 1. Didynamia Gymnospermia. Nat. ord. Verticillatas

Linn. Labiata? Juss.G. 1118. Calyx dry, nearly flat above : with the upper lip subfas-

tigiate. Corolla, upper lip somewhat arched, bifid ; lower lip with

the middle lobe cordate.Species I. Melissa officinalis.* Officinal or Common Balm. Med.

Bot. 2d edit. 335. 1. 119.Officinal. Melissa officinalis folia. Edin. Balm leaves.

■ Syn. Melisse (F.) Melisse (<?.) Melissa (7J Balsamina (S.)

Balm is a perennial plant, a native of the south of Europe,growing in mountainous situations, and flowering from Julyto September. It is cultivated in our gardens. 1 The root isfibrous, and sends up annual stems, which rise about two feethigh, and are branched, quadrangular and smooth. The leavesare opposite in pairs, of a bright green colour, ribbed, deeplyserrated, and cordate; the lower ones on long foot-stalks, andthe upper nearly sessile. The flowers, which are in small axil-lary bunches forming semi-whorls, stand on slender peduncles,at the base of which are small, oblong, notched, hairy bractes.The calyx is tubular and pentangular; the upper lip tridentate;the lower shorter, and cut into two acute teeth. The corolla,which is tubular, of a yellowish white colour, with the upper lipshorter, and notched, and the lower three-cleft, encloses theanthers; the seeds are four, ovate, and placed at the bottom ofthe calyx.

For medicinal use the herb should be cut before it flowers,as it is then more odorous.

Qualities. — The recent plant has the agreeable odour of le-mons, which is lost in drying; and an austere, slightly aromatictaste. In distillation with water, it yields a small portion of ayellow essential oil, on which its odour depends. The wateryinfusion tastes rough; reddens slightly litmus paper; and af-fords with oxysulphate of iron a deep olive, with nitrate of silvera deep brown, and with superacetate of lead a copious greenishwhite precipitate.

Medical properties and uses. —Officinal balm is stomachicand diuretic. It was formerly prized as a corroborant in Iry-

1 MeXirt^uXXdv Dioscoridis, bees being very fond of it.* It was cultivated by fjerarde in 1596.