Yarrow is one of the few aboriginal English plants, having held the primitive title, Gearwe. Greek botanists seem to have known the identical species which we now possess, and to have used it against haemorrhagic losses. It yields, chemically, a dark-green volatile oil, and achilleic acid, which is said to be identical with aconitic acid; also resin, tannin, gum; and earthy ash consisting of nitrates, phosphates, and chlorides of potash and lime.
For preparing an infusion of the plant, half an ounce should be boiled down in half a pint of water to six ounces; one tablespoonful for a dose.
Sir John Hill says the best way of giving Yarrow is in a strong decoction of the whole plant. A hot infusion of the herb taken freely on going to bed at night seldom fails to make short work of a cold.
A medicinal tincture (H.) is prepared from the whole plant with spirit of wine. This, when employed in a diluted form of the first or third decimal strength, and [618] in small doses of from five to ten drops in a tablespoonful of cold water, will act admirably in arresting nocturnal losses in the male; likewise bleeding from the lungs, the kidneys, or the nose, especially in florid, hectic subjects. It has been found by healthy provers that stronger, and larger doses of any preparation of the herb will induce or aggravate one or another of these bleedings.
The fresh juice of the plant may be had, a dessert-spoonful three times in the day; or of the volatile essential oil, from three to five drops for a dose. These medicines greatly stimulate and promote the appetite. "For ague," says Parkinson, "drink a decoction of the herb warm before the fit, and so for two or three fits together."
Externally, a strong decoction of the leaves has been used as an injection into the nostrils to stay bleeding from the nose. It is similarly of service for piles, and for female floodings, because exerting a special local action on the organs within the middle trunk. The bruised herb, or an ointment made from it, is applied by rustics to heal fresh cuts and contusions.
Even in ancient times it was famous as a topical remedy for piles. It is further of benefit for sore nipples as a lotion, and for a relaxed sore throat as a gargle: also as a hair wash.
The leaves were applied in former days as a poultice to wounds; and because of its healing and astringent virtues when so used, the plant gained the names Sanguinary, Thousand leaf, Old Man's pepper, Soldiers' Woundwort. Other local names for it are Staunch grass, Carpenters' weed, and Bloodwort: also, "Old Man's Mustard," "Bad Man's Plaything," and "Devil's Plaything." In Gloucestershire and some other parts, the double-flowered Yarrow is brought to a wedding by [619] bridesmaids as "seven years' love." In Cheshire, children draw the herb across the face to produce a tingling sensation, and they call it "Devil's nettle."
Culpeper spoke of the same as a profitable herb in cramps, and therefore called Militaris.
Yarrow, worn in a little bag over the stomach, was the secret (confided to Boyle) of a great lord against ague. A famous physician had used it with strange efficacy.