238

Materia Medica.

part if.

II

The common flax is an annual plant, flowering in July, Itis supposed to have been originally brought from those parts ofEgypt which are annually inundated by the rising of the Nile ;but it is now found growing wild in this country; and is cul-tivated in most parts of Europe. The root is simple and fi-brous. The stem is erect, round, smooth, slender and leafy;branched with a panicle at the summit, and rising about twofeet in height. The leaves are small, lanceolate, entire, ob-scurely three-nerved, smooth, sessile, standing nearly upright,and alternate on both the stem and branches. The flowersare petiolate; the calyx persistent, composed of five sharp-pointed, keeled, trinerved, ovate leaflets; and the corolla con-sists of five notched, oblong, sky-blue, streaked petals, whichspread into funnel-formed blossoms. The filaments are white,dilated, and slightly united at the base; the germen is ovate,and crowned with five blue, thread-like, spreading, reflectedstigmas. The capsule is globular, the size of a common pea,crowned with a sharp spine, formed by the junction of thespines of the valves in one point: and containing in each cellan elliptical shining seed. 1

Although this plant is extensively cultivated in Britain, yetthe greater part of the linseed used here is brought from theBaltic. The seed ripens in September ; and the plant is thenpulled up as soon as the heads begin to change brown and hang-downwards, otherwise the seeds are soon scattered.

Qualities. —.These seeds are inodorous, and have an oily,mucilaginous, sweetish taste. They are small, flat, oval, andcovered with a smooth, shining, brown-coloured cuticle, whichabounds with a mucus, that can be extracted pure by infusionin boiling water. By expression they yield one-sixth of theirweight of fixed oil. The mucus of linseed is colourless, in-sipid, inodorous, and resembles in its viscidity mucilage ofacacia gum ; but differs from it in the following particulars:Alcohol precipitates it in white flocks, but the liquid remainsclear; superacetate of lead throws down a dense precipitate; butoxy-sulphate of iron and silicated potash produce no sensibleeffect. For the qualities of the oil, see Preparations.

Medical.properties and uses. — Linseed is emollient and de-mulcent. Tiie mucus obtained by infusion is a cheap andvery useful demulcent in catarrh, pneumonia, diarrhoea, anddysentery: visceral inflammations, calculus, gonorrhoea, ardor

1 The partitions of the ceils are singular. Gaertner thus describes them : " Disse-pime'nta mcnibranaeca, comluplicata, laminis suis extrorsum partitis, ita valvularummar-ginibus insena, ut, v cv.ii haj dehiscum, illre corii follis adinstar explieentur :" and adds," Dissepimentorum inRadioia atque Lii;o fabrica, bacterids sine } u*i t^Cj *'t essentiaieiulvujus generis praebet charaaertru." Dt Fruclilus, ii. )4/,