Camphora Pharm. Lond. & Edinb. Caphura. Camphor: a solid concrete, some-what unctuous to the touch: totally volatile in the heat of boiling water, and subliming unaltered: melting in a less degree of heat into the appearance of oil; readily taking fire on a red-hot iron, and burning entirely away, with a bright white flame, and copious fumes, which condensing form foot; soluble in spirit of wine, and in oils, and in the nitrous and vitriolic acids, not in water, nor in vegetable acids. From the nitrous acid, diluted with a little water, it absorbs the stronger acid matter, and forms therewith a substance like oil, which floats on the surface of the more phlegmatic liquor: with the vitriolic, it mingles uniformly into a yellowish red fluid.

Camphor is extracted, by a process similar to that by which essential oils are obtained, from the wood and roots of a large tree of the bay-kind, growing in Japan, called by Linnaeus Laurus (camphora) foliis trinerviis lanceolato-ovatis: nervis supra basin unitis. A species of camphor is sometimes likewise found naturally concreted into little grains, in the medullary part of this and some other trees: I have in my possession a piece of a reddish wood, which seems to be part of the trunk of a large tree, and which on being split in different places exhibits camphor plentifully concreted in it.

*In the Adversaria of the learned Gaubius, is. an account transmitted by a correspondent, of* the production of camphor in the island of Sumatra, which is worthy of notice. There are, it seems, only two kinds of camphor known in commerce in the East Indies, the Sumatran and Japanese. The former is so much superiour to the latter, that the Japanese themselves readily give a hundred pounds of their own, for one pound of the Sumatran. The reason of this probably is, both that the climate of Sumatra is much warmer, and that the camphor there is entirely prepared by nature. In the northern parts of this island the camphor tree grows to such a size, that planks two feet in breadth are fawn out of its trunk. After it has flood for a certain number of years, its branches naturally crack, and an oily liquor exudes from the fif-fures. When the inhabitants observe this, they collect the oil in pieces of bamboo, and watch the time when they have learned by experience that the formation of the camphor is complete. They then, after some superstitious ceremonies, cut down the tree, and splitting the branches, which are found full of camphor, pick out the pieces, making separate parcels of the large and the small ones. They conclude with rasping the wood itself; and thus make three sorts of camphor, which they bring to the Dutch factory; felling, however, all three together by weight. The largest and fined pieces are called, in the Malay language, Copal, or head; the smaller, Poeroet, or belly; and the raspings of the wood, Cacki, or feet*(a).

* (a) The editor has been favoured with an account of the camphor tree, sent from Sumatra, which agrees perfectly with the above. The writer further says, that the Sumatran camphor tree is certainly a new genus, and not at all resembling the tribe of LauriAs first sublimed or distilled from the wood, it appears brownish, and composed of semipel-lucid grains mixed with some impure matter. In this state, it is imported by the Dutch, and purified by a second sublimation, by which it becomes clear and white: this last process is so managed, that the head of the subliming glass is kept warm enough, to make the camphor run together into a mass of its own figure; in which form it is brought into the shops. It may likewise be purified by solution in spirit of wine; recovered from the spirit by distillation, the spirit rising before the camphor; and afterwards formed into loaves by fusion, with a gentle heat, in a close vessel.

This concrete has a fragrant smell, some-what approaching to that of rosemary, but much stronger; and a bitterish, aromatic, pungent taste, accompanied with an impression of coolness. It is looked upon as one of the principal diaphoretics and antiseptics, and as pos-sessing some degree of an anodyne or antispas-modic power. It is apparently of great sub-tility and penetration, quickly diffusing itself through the habit in a very sensible manner: taken in any considerable quantity, it generally produces very uneasy sensations about the sto-mach and praecordia, and often in the remoter parts; though it does not heat the body near so much, as might be expected from the great pungency of its taste. Hoffman reports, that doses even of half a dram did not increase the pulse, or excite any immoderate heat, but oc-casioned rather a sense of coolness; and that on continuing the use of the camphor for some time, the blood became more fluid, and the quantity of watery serum, which the habit be-fore abounded with, was notably diminished.

* A remarkable account of the effects of camphor in a large dole on the relater himself, Mr. Alexander, surgeon, in Edinburgh, is contained in the Philosophical Transactions, vol. lvii. part i. After taking one scruple of this medicine, he found his pulse somewhat abated in frequency, but no other change in himself is remarked. He next took two scruples; the first effect of which was to sink the pulse from 77 to 70. In less than half an hour it returned to its former number; and at this time a giddi-ness came on, which gradually increased, till all consciousness of present, and memory of pad, objects was obliterated. Violent efforts to vomit, with strong convulsions and a temporary mania, succeeded. The pulse was now raised to 100. Some degree of recollection returned; accompanied with a sensation of violent heat, and tremors of the whole body. The exhibition of warm water now caused a rejection of great part of the camphor; and from this time its effects by degrees wore off. A great soreness and rigidity of the whole body were felt the next day and the day following. A similar account is related in a thesis de viribus camphorae by Dr. Griffin, printed at Edinburgh in 1765.