This section is from the book "An Experimental History Of The Materia Medica", by William Lewis.
Benzoe Pharm. Lond. Benzoinum Pharm. Edinb. Benjoinum; Benzoe; Asa dulcis. Benzoine or benjamin: a concrete resinous juice, obtained from a middle-sized tree, called by Dr. Dryander in Phil. Tranf. vol. LXXVII. part II. Styrax Benzoic foliis oblongis acuminatis subtus tomentosis, racemis compositis longitudine fo-liorum. This tree is a native of the East Indies, where the benzoine is extracted by making deep incisions in the upper part of the trunk, about the origin of the first branches: it is said that one tree never yields above three pounds (a). The juice exudes white, and concreting on the tree becomes yellowish, reddish, or brownish; its colour turning darker, the longer it lies exposed to the air. It is brought to us in large brittle masses, composed partly of white, partly of yellowish or light brown, and often also of darker coloured pieces: that which is cleared and contains the most white matter, called by authors benzoe amygdaloides, is accounted the best.
This resin has very little tate, impressing on the palate only a slight sweetness: its smell, especially when rubbed or heated, is extremely fragrant and agreeable. It totally dissolves in rectified spirit of wine, the impurities excepted, which are generally in very small quantity, into a deep yellowish red liquor; and in this state discovers to the taste a degree of warmth and pungency as well as sweetness. It imparts, by digestion, to water also, a considerable share of its fragrance, and a slight pungency: the filtered liquor, gently exhaled, leaves, not a resinous or mucilaginous extract, but a cry-stalline matter, seemingly of a saline nature, amounting, as I have found on several trials, to one tenth or one eighth the weight of the benzoine.
(a) Grimm, Aft. nat. curios. dec. ii. ann. 2. obs. 152. Rumph. Herbarium amboinese.
Exposed to a gentle heat, in a retort or other proper vessel, it melts, and fends up into the neck white shining flowers, similar to the cry-stals obtained by water. These are followed by a thin yellowish oil, slightly empyreumatic, intermingled with an acidulous liquor; and at length, by a thick butyraceous matter, which, liquefied in boiling water, gives out to it a little more crystalline matter, separable by filtration and proper evaporation: the whole quantity of saline matter obtainable by this method is somewhat greater than that extracted by boiling the benzoine in water. The thin oil, redistilled with water, loses its empyreumatic taint, and in this state smells agreeably of the benzoine, and appears of the same nature with essential oils: the benzoine itself, distilled with water, has not been observed, like most of the other resinous juices, to yield any essential oil.
The flowers or crystals of benzoine have a grateful saline taste, and partake of the fragrance of the resin. They dissolve in spirit of wine; and, by the assistance of heat, in water; but from this last, they separate again, in great part, as the liquor cools, shooting into saline spicula, which unite together into irregular masses: the addition of so much sugar, as will reduce the water to the consistence of a syrup, prevents their separation, the flowers continuing suspended in the syrup after it has grown cold. Distilled with water, they arise entire, concreting into their original form, without communicating any smell or taste to the distilled liquor.
Flores ben-zoes Ph. Lond.
benzoini, Ph. Ed.
These flowers, unless sublimed with a very gentle heat, are apt to be tainted with an empyreumatic smell, and a yellow colour, on account of a little of the oil being forced up with them. From this they may be purified, by mixing them with some dry tobacco-pipe clay, and subliming them afresh; or perhaps more perfectly, by solution in water, filtration, and crystallization. Though purified, however, to a snowy whiteness, they still participate of oil, and hence prove inflammable in the fire, and are subject, in long keeping, to grow yellow again. They grow sooner yellow in close vessels, than in open ones; the oil, in the latter case, being perhaps carried off by the air in proportion as it is extricated from the saline matter.
The principal use of this fragrant resin is in perfumes, and as a cosmetic; for which last purpose, a solution of it in spirit of wine is mixed with so much water as is sufficient to render it milky, as twenty times its quantity or more. It promises, however, to be applicable to other uses, and to approach in virtue, as in fragrance, to storax and balsam of Tolu. It is said to be of great service in disorders of the bread, for resolving obstructions of the pulmonary vessels, and promoting expectoration: in which intentions the flowers are sometimes given, from three or four grains to fifteen. The white powder, precipitated by water from solutions of the benzoine in spirit, has been employed by some as similar and superiour to the flowers, but appears to be little other than the pure benzoine in substance: it is not the saline but the resinous matter of the benzoine, that is most disposed to be precipitated from spirit by water. The flowers, snuffed up the nose, are said to be a powerful errhine.
Magifter. benzoini Ph. Bran. etc.