CAMPHORA. L.E.D. (Laurus Camphora.[[437]])
Camphor.
Qualities. Form, a white brittle substance, unctuous to the touch, but possessing at the same time a degree of ductility which prevents its being easily pulverised, unless a few drops of spirit be previously added. It is capable of affecting a crystalline form.[[438]] Odour, peculiar, fragrant, and penetrating. Taste, bitter, pungent, and aromatic. Specific gravity, ·9887, it therefore swims on water; it is so volatile that during warm weather a considerable proportion will evaporate, especially if at the same time the atmosphere be rather moist, for the reason stated in page 175. It is readily ignited, and burns with a brilliant flame and much smoke; it melts at 288°, and boils at 400. Chemical Composition. It is a proximate vegetable principle, resembling the essential oils in many of its habitudes, and probably differs from them in composition only in containing a larger proportion of carbon. Solubility. Water may be said to dissolve about a nine hundredth part of its weight, or f℥j rather more than gr. ½, but its solvent power is considerably increased by the addition of carbonic acid gas; camphor is also rendered more soluble by trituration with magnesia; it is soluble in an equal weight of alcohol, but it is again separated by the addition of water; it is also dissolved by oils, both fixed and volatile,[[439]] especially if their temperature be a little raised, and by sulphuric and other æthers, but strong acetic acid may be said to be its most powerful solvent. By repeatedly distilling it with nitric acid it is converted into Camphoric acid, an acid distinguished by peculiar properties, and composing, with alkalies and earths, a class of salts called Camphorates, but which do not possess any medicinal value. The alkalies do not produce any effect upon camphor. Incompatible Substances. It is not affected by any substance with which we can combine it. Forms of Exhibition. It is preferable in the form of mixture, since it is very liable in the solid state to excite nausea, and, from swimming on the contents of the stomach, to occasion pain at its upper orifice. If a larger dose be required than that which water can dissolve, an additional proportion may be suspended by means of sugar, almonds, yelk of egg, or mucilage, for which purpose three times its weight of gum arabic is required. If Camphor be first dissolved by trituration in a very small portion of oil, it readily mixes with mucilage of gum arabic, and may then be conveniently blended with liquids. It has also the property of uniting with gum-resins, and of converting them into permanently soft, and uniform masses; hence they may sometimes be conveniently applied for diffusing it in water. It may be formed into pill-masses by stiff mucilage, fœtid gums, or by a confection. Medicinal Uses. In moderate doses it exhilarates, without raising the pulse, and gives a tendency to diaphoresis; and under certain conditions of the body, when opium fails, it will frequently promote sleep. As its effects are transient, its dose should be repeated at short intervals. Illustrative Formulæ 1, 6, 21, 125, 134, 164. Camphor is said to correct the bad effects of opium, mezereon, cantharides, and the drastic purgatives, and diuretics. Dose, gr. ij to ℈j. In excessive doses it occasions anxiety, vomiting, syncope, and delirium; these violent effects are best counteracted by opium. Officinal Preparations. Mistura Camphoræ. L.D. Emulsio Camphorata. E. Spiritus Camphoræ, L.E.D. Tinctura Camphoræ comp: L.E.D. Acidum Acetosum Camphoratum. E.D. Linimentum Camphoræ. L.E.D. Liniment: Camphoræ comp: L. Liniment: Saponis. (G) L.E.D. Adulterations. It has been stated that pure camphor may be known by placing it upon hot bread, when it will turn moist, whereas an adulterated specimen becomes dry—but with what can it be adulterated?
CANELLÆ CORTEX. L.E.D. Canella Bark, (Canella Alba Cortex.)
Wild Cinnamon.
Qualities. Form; it occurs in quilled and flat pieces; the former are of a whitish-yellow colour, considerably thicker than cinnamon; the latter, which are probably the bark of the larger branches, or of the stem of the tree, are yellow on the outside, and pale brown within. Odour, resembling that of cloves. Taste, warm, pungent, and slightly bitter. Chemical Composition. Its virtues depend upon an essential oil, and a bitter resin. Solubility. Water extracts only the bitterness, but proof spirits both the bitterness and aroma. Medicinal Uses. As a warm stimulant to the stomach, and as a corrigent to other medicines. In America it is considered as a powerful antiscorbutic. Dose of the powdered bark gr. x to ʒss. Officinal Preparations. Tinct. Gentian. comp. (B. G.) E. Vinum Aloes, (G) L.D. Pulv. Aloes cum canella, (G) D.
CANTHARIDES.[[440]] (Cantharis Vesicatoria.)
Blistering, or Spanish Flies.
This beautiful insect of the beetle tribe is exceedingly abundant in the southern parts of Europe, and particularly in Spain. They are collected from the leaves of the different trees on which they delight to dwell, in June and July, and are afterwards destroyed, as recommended by Dioscorides, by the fumes of strong vinegar, and dried in the sun. The chemical history of Cantharides is still involved in some obscurity; the blistering principle has been obtained by Robiquet in a separate state, when it assumes the form of small crystalline plates, having a micaceous lustre, not unlike spermaceti; Dr. Thomson has given to it the name of Cantharidin;[[441]] when pure, it is insoluble in water and in cold alcohol; boiling alcohol, however, dissolves it, but precipitates it again on being cooled. Æther and the oils dissolve it readily. Although not soluble in water it is rendered so by the presence of a yellow matter which exists in native combination with it. A very minute portion of this substance dissolved in sweet oil, and applied to the skin with a piece of paper, produces vesication in five or six hours. In addition to this active principle, Cantharides contain a green concrete oil; a yellow fluid oil; a peculiar black substance soluble in water and proof spirit, but not in pure alcohol; a saponaceous or yellow substance, soluble both in water and alcohol; Uric acid; Acetic acid; Phosphate of Magnesia, and a parenchymatous substance.[[442]] Medicinal Uses. Cantharides, when administered internally, are powerfully stimulant and diuretic;[[443]] and whether applied as a vesicatory to the skin, or taken into the stomach, they have a peculiar tendency to act upon the urinary organs, and especially to irritate and inflame the neck of the bladder, and occasion strangury. On this account they have been very successfully employed both for the cure of incontinence of urine, and suppression of this discharge, from torpor or paralysis of the bladder; they have also been used in gleet and leucorrhæa, and in cases of seminal weakness and impotence. In consulting the works of Dioscorides, Galen, and Pliny, we shall find they entertained a notion, that the virus existed only in the body of the fly, and that the head, feet and wings, contained its antidote! Hippocrates prescribed them internally in Dropsy, Jaundice, and Amenorrhœa; and yet in the end of the sixteenth century, Dr. Groenvelt was charged and sued[[444]] for giving them inwardly, in substance, for the cure of the stone. Dose, in substance, not exceeding gr. i, combined with opium or hyoscyamus. See Tinctura: Cantharid. A strong decoction of the Cantharides in Oil of Turpentine furnishes a most powerful Epispastic, and may be easily applied by means of dossils of lint. As the general belief, which exists with respect to the aphrodisiac powers of this substance, may induce persons to try its efficacy in large doses, either for goading the exertions of exhausted nature, or for incensing the passions of females whose seduction is meditated, it behoves the medical practitioner to become acquainted with the symptoms which it may produce, and of which the following may be considered as the most prominent;—violent retching; copious alvine evacuations, frequently bloody; very severe colics; active inflammation of the stomach and intestines; sometimes universal convulsions, attended with a horror of liquids, resembling that which occurs in hydrophobia; furious delirium, &c. But the affections of the urinary passages, and organs of generation, may be regarded κατεξοχην, as the peculiar symptoms of poisoning by Cantharides; such as heat in the bladder, bloody micturition, horrible strangury, painful and obstinate priapism, satyriasis, &c. The method of treatment to be pursued on such occasions will consist in copious bleeding, warm bath, local fomentations, mild and mucilaginous drinks; and opium, especially in the form of clyster or suppository. Officinal Prep. Tinct: Cantharid: L. Emplast: Cantharid: L. Ceratum Cantharid: L. Unguent: Infusi Cantharid: Vesicat: E. Unguent: Cantharid: D. The flies do not lose their virtues by being kept; it is, however, curious that even those acrid insects are soon reduced to dust by others feeding upon them; but since the inert parenchymatous portion is alone selected by them, the residue is extremely active.[[445]]
CAPSICI BACCÆ. L.E.D. Berries of the Capsicum. (Capsicum Annum.)