Spec. Plant. Willd. ii. 199. Cl. 6. Ord.1. Hexandria Monogynia. Nat. ord. Acoraceae. G. 663. Spadix cylindrical, covered with florets. Cor. petals six, naked. Style O. Capsule three-celled. Species 1. A. Calamus. The Sweet-flag. Med. Bot. 3d edit. 725.

t. 248. Smith, Flor. Brit. i. 373. Officinal. Acorus, Lond. Acori Calami Radix, Edin. Sweet-flag.3

Syn. Acorus odorant (F.), Kalmus wurzel (G.), Kalmus (Dutch, Dan. Swed.), Calamo aromatico (I.), Acora calamo (S.), Tatarskie Ziele (Polish), Vassamboo ( Tarn.), Vadge(Pers.), Shivah Buch (Beng.) Igir (Arab.), Wudda Kuha.(Cyng.), Bach (H.), Vacha (San.), Deringgo (Javanese).

The sweet-flag is found growing in marshes and rivulets, over the greater part of Europe and Asia. It is abundant in all the marshy counties of Britain, producing its flowers in May and June.4

1 De Candolle informs us that the peasants employ it to cure dropsy.

2 The tincture is made by digesting one part of leaves of aconite in six parts of alcohol; it may be given in doses of from v. to x., gradually increased to xl.

Dioscondis.

4 In the rivers of Norfolk plentiful. On Hilhngdon-common, Middlesex, and other places about London. Smithy 1. c.

The rhizome is perennial, horizontal, long, somewhat flatted, crooked, and full of joints or rings, whence the radical fibres or roots spring from the underside. It is from half an inch to one inch in thickness; externally, when fresh, of a greenish yellow colour, internally whitish and spongy. The leaves spring directly from the root; are sword-shaped, about three feet in length, and generally waved along one of the edges; of a bright green colour, and emitting a strong aromatic odour when bruised. The flowers are hermaphrodite, surrounded with scales, small, and produced on a very close, tessellated, conical spike four inches long, pushed out from the side of a naked stalk or scape, two-edged, and terminating like a leaf. They have no calyx. The petals are six, small, erect, regular, with the apex inflected, and of a pale green colour. The filaments are alternate, with the petals, threadlike, supporting double anthers. The germen is elliptical, crowned with a sessile-pointed stigma : the fruit bascate, but juiceless.

The greater part of the rhizomes in use are brought from Norfolk; and are equal in quality to those imported from the Levant.

Qualities.-The rhizome of sweet-flag has a pleasant aromatic odour, similar to that of a mixture of cinnamon and allspice; the taste is warm, bitterish, pungent, and aromatic.1 In the dried state, the cuticle is corrugated, of a yellowish brown colour, with many small, white, elevated circles on the under side, whence the radical fibres issued. It breaks with a short rough fracture; is internally of a pale rosy buff colour, its texture is spongy: both the smell and taste are lessened by exsiccation. The aromatic principle is a volatile oil, which can be obtained by distillation. According to Volter and Dann, 14 lbs. of the dried rhizomes yield 3 xxij of volatile oil. The bitter matter, extractive gum, and inuline, with a small proportion of oil, are extracted by infusion in boiling water. The rhizomes contain a considerable quantity of fecula, which is dissolved in the infusion, and copiously precipitated from it by the acetates of lead.

Medical properties, and uses.-This rhizome is tonic and aromatic. It has been employed in medicine since the time of Hippocrates.2 By the moderns, it is successfully employed in intermittent fever, even after bark has failed; and is certainly a very useful addition to Cinchona. It is also an

1 Linnaeus erroneously considered it the only native aromatic plant of northern climates.-The candied root is employed at Constantinople as a preservative against epidemic diseases.

2 Morb. Mul. ii. 951.

appropriate adjunct to bitters, and stomachic infusions, in cases of dyspepsia; particularly when vertigo is one of the symptoms. It is too seldom prescribed. The dose in substance is from gr. x. to 3 j.: and of the infusion, made with 3 vj. of the bruised rhizome in f xij. of boiling water, a cupful may be given three or four times a day.