This section is from the book "Meals Medicinal", by W. T. Fernie. Also available from Amazon: Meals Medicinal: With "Herbal Simples" Curative Foods From the Cook in Place of Drugs From the Chemist.
Grated Horse Radish, if eaten at frequent intervals during the day, and likewise at meals, is found remarkably efficacious for getting rid of the persistent distressing cough which lingers after influenza. The root of Horse Radish contains sulphur, a volatile oil, a bitter resin, sugar, starch, gum, albumin, and acetates. Chemically its volatile oil is identical with that of mustard, being highly diffusible, and pungent, because of the "myrosin." One drop of this most volatile oil will suffice to odorize the atmosphere of a whole room. The root is expectorant, anti-scorbutic, and, if taken too freely, emetic. That it contains a somewhat large proportion of sulphur is shown by the black colour given to silver, and other metals with which it comes in contact. Because of this constituent the plant proves serviceable in chronic rheumatism, and for remedying scurvy. Bergius alleges that by cutting the root into very small pieces, without bruising it, and then swallowing a tablespoonful of these segments every morning without chewing them, throughout three or four weeks, a cure has been effected of chronic rheumatism which had proved intractable by all else which was tried. The sulphuretted oil is crystallizable.
As to an outward use of Horse Radish, Gerarde has said about the root: "If bruised, and laid to a part grieved with the sciatica, gout, joynt-ache, or the hard swellings of the spleen, and liver, it doth wonderfully help them all." The botanical name Cochlearia implies a resemblance between the leaves of the plant and an old-fashioned spoon, cochleare. Formerly it was named Mountain Radish, and Great Raifort, (as now styled in France,) or Cran. When scraped it exhales a nose-provoking odour, and possesses a hot, biting taste, combined with a certain sweetness; on exposure to the air it quickly changes colour, and loses its volatile strength. Taken by itself, or in a plain sauce (but not being boiled) with oily fish, or rich, fatty viands, scraped Horse Radish acts as a spur to complete digestion thereof; at the same time it can benefit a relaxed sore throat by contact during the swallowing. When sliced across with a knife the root will exude some drops of a sweet juice which may be rubbed beneficially into rheumatic, or palsied limbs. An infusion of Horse Radish, sliced, or bruised, in cold water makes an excellent gargle, which should be sweetened with honey, or glycerine.
Also an infusion of sliced Horse Radish in milk, forms, by virtue of its contained sulphur, and by its stimulating pungency, an excellent cosmetic for the skin when lacking clearness, and freshness of colour. A mixture of recent Horse Radish juice, with white vinegar, will, if applied externally, do much towards removing freckles. When indolent pimples with a white head (acne) affect the skin, particularly at puberty, if each of these is touched now and again with some compound spirit of Horse Radish from the chemist, then the several pimples will be aborted, and will be dispersed without giving further trouble. For a relaxed throat, with loss of voice, a strong syrup of Horse Radish may be concocted, some of which should be mixed with water (a teaspoonful thereof to a wineglassful of cold water), and used freely as a gargle. Again, if the scraped root is macerated in vinegar it will form a mixture which, when sufficiently diluted with water, and sweetened, with glycerine, will give marked relief in whooping-cough of children, the dose being from one to two dessertspoonfuls according to age.
Care should be had not to mistake poisonous aconite root for Horse Radish root when digging it up; the two roots really differ in shape, and colour; furthermore, aconite leaves, if present, cannot be easily mistaken for those of any other plant, being completely divided to their base into five wedge-shaped lobes, which are again subdivided into three. Scraped Horse Radish, if applied to recent chilblains, and secured with a light bandage, will help to cure them. For facial neuralgia some of the fresh scrapings, if held in the hand of the affected side, will give relief, the hand becoming in some cases within a short time bloodlessly white, and benumbed. When infused in wine, Horse Radish root will stimulate the whole nervous system, and promote perspiration, whilst acting further to excite a free flow of urine. If applied topically for pleuritic pain in the side, the bruised root will mitigate such pain.