« AnteriorContinuar »
ARBUTUS [ARCTOSTAPHYLOS] UVA URSI.
Class X. DECANDRIA.—Order I. MONOGYNIA.
NATURAL ORDER, ERICE Æ.-THE HEATH TRIBE.
Fig. (a) represents the calyx; (6) a flower cut open to show the stamens; (c) a stamen, with its anthers; (d) the berries ; (e) a berry
divided transversely, to show the seeds.
This pretty evergreen shrub is met with both in the old and new continents; for, in the northern parts of Europe, it abounds in Sweden, Lapland, and Iceland; it is extensively diffused over Scotland and the north
represented as abundant on the banks of the Wolga; while in North America it grows from Hudson's Bay, as far south as the central parts of the United States.
With us, it occurs only in dry, stony, subalpine moors, covering the ground with beds of considerable extent, at the height of 1,500 feet and upwards above the level of the sea. It is common throughout the Highlands, and Western Islands of Scotland, and abounds at Dunkeld and Blair, the seats of the Duke of Athol, in Perthshire.
The root is perennial, long, and fibrous; sending off several round, woody, branched, spreading, procumbent stems, covered with a smooth deciduous bark. The leaves are not unlike those of the Box, alternate, evergreen, obtuse, ob-ovate, entire, attached by short stalks, coriaceous, smooth, convex, dark green, and wrinkled above; concave, finely reticulated and paler beneath, with the margin rounded, and in the young ones pubescent. The flowers which are produced in June, grow in small clusters at the extremity of the branches, each supported on a short red footstalk, and furnished with many acute coloured bracteas. They are usually five or six on each branch, drooping, and of a rose-red colour. The calyx is small, obtusely 5-toothed, and persistent. The corolla is ovate, smooth, transparent at the base, contracted at the mouth, with five short reflexed segments. The filaments are awl-shaped, downy, inserted at the base of the corolla, and crowned with reddish incumbent anthers, of two oval cells, opening by two terminal pores, and bearing a pair of short horns or spurs. The germen is roundish, bearing a cylindrical erect style, the length of the corolla ; with a simple stigma. The fruit is a small, globular, smooth, depressed scarlet berry, containing a mealy pulp of an austere taste, and four or five angular seeds.
The plants of this genus are very nearly allied to those of the Vaccinium, or Whortle-berry, from which they differ principally in the situation of the berry, which in the Arbutus grows above the calyx; and in the Vaccinium below it. The present species may be distinguished from the Arbutus alpina, or Black Bearberry, by the figure of the leaves, which in the former are smooth, and entire, while in the latter they are rugged, and serrated.
QUALITIES AND CHEMICAL PROPERTIES.—The leaves of this plant, which are the parts used in medicine, are slightly bitter, and astringent to the taste. The result of Dr. Bigelow's chemical trials with them, shows that they abound in tannin. A solution of jelly occasioning a copious precipitate; sulphate of iron an equally copious one of a black colour. Nitrate of mercury gives a percipitate of a light green colour: lime-water, of a brownish colour. The existence of gallic acid is somewhat problematical ; and the quantity of resin, mucous matter, and extractive, provided they reside in the plant, must be minute; since the decoction is not rendered turbid by the addition of alcohol, or ether, nor the tincture by the addition of water. Muriate of tin produced no precipitation from the decoction, though it did from the tincture. Acetate of lead, and nitrate of silver, gave large precipitates. Water takes up a larger portion of soluble matter than alcohol, and may therefore be considered the best menstruum. Professor Murray, of Gottingen, prefers the decoction to the infusion for medical purposes.
MEDICAL PROPERTIES AND Uses.—The Arbutus Uva-ursi is supposed by Clusius to be the apkter otapuan of Galen, celebrated by him as a remedy in hæmoptysis, and described as follows; “ Uva-ursi in Ponto nascitur, planta humilis et fruticosa, folio Memæcyli, fructum ferens rubrum, rotundum, gustu austerum.” But this description is too imperfect to satisfy us as to the identity of the plant.
As a diuretic, uva-ursi has been employed for calculous affections, especially when attended by purulent discharges. De Haen speaks very favourably of it in such cases; and as it has a tendency rather to decrease arterial action, than to augment it, it may be exhibited in almost every state of the system, and in nearly every variety of diseases. To its great efficacy in some of these affections, Ferrier gives his decided testimony. “I hare,” says he, "given this medicine in a considerable number of nephritic affections in very moderate doses, and always with manifest advantage. When the pain is very acute, and the pulse quick, I begin the cure with bleeding, and a gentle purgative composed of manna, and neutral salts. This purgative I repeat twice a week, and on the intermediate days direct the patient to take five grains of the uva-ursi, and half a grain of opium, three or four times a day, according to the urgency of the symptoms. This method always relieves, and generally effects a cure. Of sixteen patients treated in this manner, I have discharged twelve cured. On reckoning the cures, I do not rest on the cessation of a single fit, but require a permanent relief from pain. Many of my patients have used this remedy for several months together, before this end was attained. The fits became slighter, and at length ceased.”
Conjoined with soda it is an admirable remedy for catarrhus vesicæ and for strangury, arising from blisters. It is frequently resorted to for diabetes, and after the febrile symptoms which usually attend that disease, have been reduced by copious bleeding, &c.
It was in consequence of its apparent virtue in counteracting a protracted disease attended with emaciation, and all the characteristics of hectic fever, that Dr. Bourne, of Oxford, was induced to make trial of its efficacy in phthisis pulmonalis, and other affections rendered in some measure analogous to genuine pulmonary consumption, hy the decided existence of hectic irritation. After a recital of the case above alluded to, Dr. Bourne, in his work, minutely details the symptoms and method of treatment in sixteen separate cases, which are arranged under four general heads. The first eight are supposed to be instances of“ true pulmonary consumption in its first stage,” the ninth, tenth, and eleventh of this disorder in a confirmed state, attended with purulent expectoration; the two succeeding, some affections of the lungs attended with expectoration of pus, but which, nevertheless, were not genuine phthisis; and the three last were cases of hectic, in which the lungs appeared not to be primarily affected, or not at all. In the majority, however, of the above cases, the uva-ursi was not had recourse to without auxiliary combinations, and in some instances its employment was for a time entirely suspended. In the cases which are recited in the Appendix, the medicine appears to have received a fairer trial, and to have been attended with more decided effects. Extreme candour and moderation pervade the pages of Dr. Bourne's work; and although our own experience of uva-ursi in pulmonary affections does not authorize an opinion independently of that formed by a perusal of this book, Mr. Davie, of Framlingham, Suffolk, has given cases of its decidedly curative powers; and there can be little doubt of its being capable of allaying irritability of system; for, according to experiments instituted on the pulse by Dr. Mitchell, of Philadelphia, the beats were sometimes, not always, slightly increased after taking it, but in every case they soon sunk below the natural standard, and remained so for some time.
Of the powder of the leaves of uva-ursi, from one to two scruples may be given to most patients; and of a decoction, made from half an ounce of the leaves, boiled for ten minutes in a pint of water, and a wineglassful may be taken every hour.
The fruit of the Arbutus Uredo, taken in too great quantity, is said to be narcotic.