Spec. Plant Willd. ii. 567. Cl. 10. Ord. 10. Decandria Monogynia. Nat. ord. Simarubiaceae. G. 849. Flowers hermaph. Calyx short, with five deeply-divided segments. Petals five. Species 3. Q. excelsa. Trans. Roy. Soc. Edin. iii. 205-210.

t. 6. Officinal. Quassia, L. E. D. The wood of Quassia.

Syn. Bois du Quassie (F.), Quassienholz (G.), Legno della Quassia (I.), . Leno de Quassia (S.), Pao de Quassia (Port.).

This species of quassia grows in the natural woods of Surinam, Jamaica, and the Caribbean islands, where it is called the bitter ash; and flowers in October and November. It is a beautiful tall tree, rising sometimes one hundred feet in height, with a straight, smooth, tapering trunk, often ten feet in circumference near the base; and covered with a smooth grey bark. The leaves are pinnate, consisting of from five to eight opposite pairs of leaflets, with a terminal leaflet; they are oblong and pointed; the ribs reddish; and the young leaves are covered with a fine brown down. The flowers are in clusters from the lower part of the last shoot before the leaves: they are small, of a yellowish green colour, with a very small calyx: the male flowers are nearly similar to the hermaphrodite, except that they have the rudiments only of a style. The fruit is a small black drupe, round, the size of a pea, and attached in threes, sideways, to a round fleshy receptacle. It is ripe in December, and is not bitter.1 The wood is sent to this country in billets, and is reduced to chips, or rasped, by the druggists.2

Qualities.-Quassia wood is inodorous, and has an intensely bitter taste; it is of a pale yellow colour. Alcohol and water take up its bitterness, and, when evaporated to dryness, leave a brownish yellow, somewhat transparent, brittle extract, which has been regarded as a vegetable constituent sui generis, and named qitassina, or the bitter principle.3 I am inclined to believe that this principle, although not itself of a resinous nature, is connected with resin, as ether takes it up, and the tincture, when evaporated on water, which becomes intensely bitter, leaves an insoluble pellicle that has the character of a resin. The infusion is rendered muddy by nitrate of silver, a soft, flaky, yellow precipitate being formed; and acetate of lead occasions a copious white precipitate: thence, these salts are incompatible in formulas with it; but it is not affected by tartarized antimony, nor sulphate of iron, nor gelatine.

1 Edin. Phil. Trans, iii. 207.

2 It is asserted, that of late years the brewers have used quassia wood instead of hops. Beer made with it certainly docs not keep, but soon becomes muddy, flat, has a mawkish taste, and runs into the acetous fermentation. Mr. Brande says, an infusion of quassia sweetened with brown sugar is an effectual poison for flies. -Manuel, p. 46.

3 Thomson's Chymistry, 4th edit. v. 32.

Medical properties and uses.-Quassia is tonic. It has been found efficacious in dyspepsia and nervous irritability, intermittent and bilious remittent fevers, chlorosis, diarrhoea; and, when combined with cretaceous powder and ginger, in atonic gout. It does not sensibly quicken the circulation, nor augment the animal heat. We have given it, combined with nitric acid, with evident benefit in typhus, gout, and also in fluor albus. Infusion is the best form of administering quassia; the raspings, for it cannot be properly pulverized, being too bulky : but it may, nevertheless, be given in substance in doses of from grs. x. to 3 j. three or four times a day.

Officinal preparations.-Infusum Quassiae, L. D. Tinctura Quas-siae excelsae, E. D.