The Physiomedical Dispensatory by William Cook, M.D., 1869
Description: Natural Order, Oxalidaceae. These plants are low herbs, growing in shady woods, with slender and weak stems about six inches high, on the summit of which are three leaflets of an ob-cordate shape, with broad and rounded lobes. The flowers grow on slender scapes a little longer than the leaf-stalks, a single nodding flower to each; sepals five, persistent; petals five, white, delicately vined with purple, and a yellowish base; stamens sixteen and monodelphous; styles five and separate, blooming in June. The species STRICTA is much more common than the acetosella. The stem in it is somewhat branched; leaves numerous, and often folding up in the heat of the day; flowers small, chrome yellow, and borne in small umbels, blooming the whole summer. Both species have an agreeable acid taste; and from the fact that oxalic acid can be obtained from them, the technical name oxalis has been given to them. But this acid does not exist in the plant in its natural state, and can not be obtained except as the herb is caused to undergo fermentation, or decomposed with potassa solution, when binoxalate of potassa is obtained; or else treated with nitric acid, as in the manufacture of oxalic acid from sugar, starch, and similar organic substances. (See section 32, Therapeutics; and Amygdalus communis.)
Properties and Uses: This herb, freshly gathered, is well bruised in a mortar, and then subjected to strong pressure. The juice thus obtained is put in shallow earthen dishes, and evaporated in the sun. A soft extract is thus obtained without any fermentation whatever; whence this extract in no sense resembles oxalic acid, as Newton and some others have asserted. This extract makes a powerful application in the treatment of cancer; and many reliable reports have from time to time been made in which scirrhus was eradicated quite effectually by plasters of this article. The application of it causes much suffering, which may be mollified by admixture with extract of taraxacum; but it unquestionably has a decided power in causing the ejection of the cancerous deposits, (roots,) and promoting the healing of such degenerate sores. Mixed with cerate or other unguent, it is equally powerful in arousing old and truly indolent ulcers into vital action. The usual procedure in all these cases, is to apply once a day a plaster of the extract, as free from mollifying combination as the case will admit, and continue it as long as the patient can well endure; and then to remove it, and apply some simple emollient salve. Rumex acetosella is used for the same purposes, and possesses properties nearly identical with this oxalis; and the extract of these plants constitutes the basis of probably three-fourths of the marvelous cancer-cures with which such a large portion of mankind is steadily humbugged, and some preparation of arsenic makes up the remaining one-fourth.
Medical Herbalism journal and medherb.com