Myrrha Pharm. Lond. & Edinb. Myrrh: a gummy-refinous concrete juice, of an oriental tree, of which we have no certain account. * Mr. Bruce informs us that it grows spontane-ously in the eastern part of Arabia felix, and in that part of Abyssinia which the Greeks named Troglodytria; and that the Abyssinian myrrh, which is the least plentiful, is the best. The best kind is that which slows from deep incisions of the larger branches, hardening upon the tree. It continues to distil every year from the same wound; but the myrrh is of an inferiour quality after the first, being mixed with foreign impurities, and the decayed juices of the tree. The worst is that which comes from near the root, or the old trunks (c). It comes over in glebes or drops, of various colours and magnitudes: the best sort is somewhat transparent, friable, in some degree unctuous to the touch, of an uniform brownish or reddish yellow colour, often streaked internally with whitish semi-circular or irregular veins; of a moderately strong, not disagreeable smell; and a lightly pungent, very bitter taste, accompanied with an aromatic flavour, but not sufficient to prevent its being nauseous to the palate.

(a) Geoffroy, Tract. de materia medica, torn. ii. p. 332.

(b) Benancius, Declaratio frauduml & error urn apud phar-macopaeos, e mufeo Bartboliniy p. 68.

(c) Philos. Trans. vol. lxv. p. 408.

There are sometimes found among it hard shining pieces, of a pale yellowish colour, re-sembling gum-arabic, of no taste or smell: sometimes masses of bdellium, darker coloured, more opake, internally softer than the myrrh, and differing from it both in smell and taste: sometimes an unctuous gummy-resin, of a moderately strong somewhat ungrateful smell, and a bitterish very durable taste, obviously different both from those of bdellium and myrrh: sometimes likewise, as Cartheufer ob-serves, hard compact dark coloured tears, less unctuous than myrrh, of an offensive smell, and a most ungrateful bitterness, so as, when kept for some time in the mouth, to provoke reaching, though so refinous, that little of them is dissolved by the saliva. Great care is thereforequisite in the choice of this drug.

This bitter aromatic gummy-resin is a warm corroborant, deobstruent, and antiseptic. It is given from a few grains to a scruple and upwards, in uterine obstructions, cachexies, putrid fevers, etc. and often employed also as an external antiseptic and vulnerary. *In doses of half a dram, Dr. Cullen remarks that it heated the stomach, produced sweat, and agreed with the balsams in affecting the urinary paffages. It has lately come more into use as a tonic in hectical cases, and is laid to prove less heating than most: other medicines of that class.

Myrrh dissolves almost totally in boiling water, but as the liquor cools, a portion of refinous matter subsides. The strained solution is of a dark yellowish colour, somewhat turbid, smells and tastes strongly of the myrrh, and retains both its taste, and a considerable share of its scent, on being infpiffated with a gentle heat to the consistence of an extract. By dis-tillation with a boiling heat, the whole of its flavour arises, partly impregnating the distilled water, partly collected and concentrated in the form of an essential oil; which is in smell extremely fragrant, and rather more agreeable than the myrrh in substance, in taste remarkably mild, so ponderous as to sink in the aqueous fluid, whereas the oils of most, perhaps of all, of the other gummy-resins swim: the quantity of oil, according to Hoffman's experiments, is about two drams from sixteen ounces, and when the myrrh is of a very good kind, near three drams.

Rectified spirit dissolves less of this concrete than water, but extracts more perfectly that part in which its bitterness, flavour, and virtues, reside: the refinous matter, which water leaves undissolved, is very bitter; but the gummy matter, which spirit leaves undissolved, is insipid, the spirituous solution containing all the active parts of the myrrh. Tinctures of myrrh, made by digesting three ounces of the concrete in two pounds and a half of rectified † or a pint and a half of proof‡ spirit, with half a pint of rectified, are kept in the shops, and given sometimes internally from fifteen drops to a tea-spoonful, but oftener used among us externally for cleansing ulcers and promoting the.

Tinct. myrrh. † Ph. Ed.

‡ Ph. Lond, the exfoliation of carious bones: both tinctures are of a reddish yellow colour. In distillation, rectified spirit brings over little or nothing of the flavour of the myrrh: the extract, obtained by inpiffating the tincture, is a fragrant, bitter, very tenacious resin, amounting to one third or more of the weight of the myrrh employed.