The Camphor of commerce is secreted by trees of the laurel sort native to China and Japan, whilst coming also from the West Indies. Everyone knows by sight and smell the white crystalline granular semi-translucent gum, strongly odorous, and having a warm pungent characteristic taste. Branches, leaves, and chips of the trees are soaked in water until it is saturated with the extract, which is then turned out into an earthen basin to coagulate. This is completely soluble in spirit of wine, but scarcely at all in water; nevertheless, if a lump of the Camphor be kept in a bottle of fresh water, to be drawn off from time to time as required, it will constitute Camphor julep. A wineglassful of it serves to relieve nervous headache and hysterical depression.
The domestic uses of Camphor are multiple, and within moderate limits perfectly safe; but a measure of caution should be exercised, as was shown a while ago by the school-boy, whom his mother furnished affectionately after the holidays with a bottle of supersaturated pilules to be taken one or two at a time against any incipient catarrh or cold. The whole bottleful was devoured at once as a sweetmeat, and the lad's life was rescued with difficulty because of intense nervous shock occasioned thereby.
An old Latin adage declares that Camphora per nares emasculat mares, "Camphor in excess makes men eunuchs," even when imbibed only through the air as a continuous practice. And, therefore, as a "similar" the odorous gum, in small repeated doses, is an excellent sexual restorative. Likewise, persons who have taken poisonous, or large [338] probative quantities of Camphor found themselves quickly affected by exhausting choleraic diarrhoea; and Hahnemann therefore advised, with much success, to give (in doses of from one to three or four drops on sugar), repeatedly for cholera, a tincture of Camphor (Rubini's) made with spirit of wine above proof. This absorbs as much as is possibly soluble of the drug.
Physiologically Camphor acts by reducing reflex nervous irritability. Externally its spirit makes an admirable warming liniment, either by itself, or when conjoined with other rubefacients. In persons poisoned by the drug, all the superficial blood vessels of the bodily skin have been found immensely dilated; acting on a knowledge of which fact anyone wishing to produce copious general sweating, may do so by sitting over a plate on which Camphor is heated, whilst a blanket envelops the body loosely, and is pinned round the neck so that the fumes do not get down the throat.
In medical books of the last century this substance was called "Camphire." To a certain extent its effluvium is noxious to insects, and it may therefore be employed for preserving specimens, as well as for protecting fabrics against moths. But its volatile odours swiftly evaporate, and become even offensively diffused about the room. In a moderate measure Camphor is antiseptic, and lessens urinary irritation. Recently a dose of ninety-six grains, taken toxically, produced giddiness, then epileptic convulsions, with dilated pupils, and stertor of breathing.
The Peppermint (Mentha piperita), or "Brandy Mint," so called because having a pungent smell, and taste of a peppery (piper) nature, is a labiate plant, found not uncommonly in moist places throughout Britain, and occurring of several varieties. Both it and the Spearmint [390] probably escaped from cultivation at first, and then became our wild plants. Its leaves and stems exhale a powerful, refreshing, characteristic aroma, and give a taste which, whilst delicate at first, is quickly followed by a sense of numbness and coldness, increased by inspiring strongly. Preparations of Peppermint, when swallowed, diffuse warmth in the stomach and mouth, acting as a stimulating carminative, with some amount of anodyne power to allay the pain of colic, flatulence, spasm, or indigestion. This is through the powerful volatile oil, of which the herb yields one per cent.
Its bruised fresh leaves, if applied, will relieve local pains and headache. A hot infusion, taken as tea, soothes stomach ache, allays sickness, and stays colicky diarrhoea. This will also subdue menstrual colic in the female. The essential oil owes its virtues to the menthol, or mint camphor, which it contains.
The Peppermint is largely grown at Mitcham, and is distilled on the ground at a low temperature, the water which comes away with the oil not being re-distilled, but allowed for the most part to run off.
Chinese oil of Peppermint (Po Ho Yo) yields menthol in a solid crystalline form, which, when rubbed over the surface of a painful neuralgic part, will afford speedy and marked relief, as also for neuralgic tooth-ache, tic douloureux, and the like grievous troubles. It is sold in diminutive bottles and cases labelled with Chinese characters. An ethereal tincture of menthol is made officinally with one part of menthol to eight parts of pure ether. If some of this is inhaled by vaporisation from a mouthpiece inhaler, or is sprayed into the nostrils and hindermost throat, it will relieve acute affections thereof, and of the nose, by making the blood vessels contract, and by arresting the flow of mucous discharge, [340] thus diminishing the congestion, and quieting the pain. This camphoraceous oil was formerly applied by the Romans to the temples for the cure of headache. In local rheumatic affections the skin may be painted beneficially with oil of Peppermint. For internal use, from one to three drops of the oil may be given as a dose on sugar, or in a spoonful of milk; but the diluted essence, made from some of the oil admixed with spirit of wine, is to be preferred. Put on cotton wool into the hollow of a carious tooth, a drop or two of the essential oil will often ease the pain speedily. The fresh plant, bruised, and applied against the pit of the stomach over the navel, will allay sickness, and is useful to stay the diarrhoeic purging of young children. From half to one teaspoonful of the spirituous essence of Peppermint may be given for a dose with two tablespoonfuls of hot water; or, if Peppermint water be chosen, the dose of this should be from half to one wineglassful. Distilled Peppermint water should be preferred to that prepared by adding the essence to common water. Lozenges made of the oil, or the essence, are admirable for affording ease in colic, flatulence, and nausea. They will also prevent or relieve sea-sickness.
When Tom Hood lay a dying he turned his eyes feebly towards the window on hearing it rattle in the night, whereupon his wife, who was watching him, said softly. "It's only the wind, dear"; to which he replied, with a sense of humour indomitable to the last, "Then put a Peppermint lozenge on the sill."