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.
The Herb Rue (Ruta Graveolens), which is cultivated in our kitchen gardens, deserves passing mention as a useful medicament, though it scarcely comes into our culinary service with food. This shrub has a pungent aromatic odour, and a hot, bitter, penetrating taste, with leaves of a bluish-green colour which are ever green, and are so acrid that if they be much handled they inflame the skin. If a leaf or two of Rue be chewed, a refreshing aromatic flavour will pervade the mouth, and any nervous headache, giddiness, hysterical spasm, or cardiac palpitation will be speedily relieved. The most important chemical constituents of the herb are its volatile oil, which contains caprinic, pelargonic, caprylic, and cenanthylic acids, also oxygenated caprinic aldehyde. Gerarde says: "The Wild Rue venometh the hands that touch it, and will also infect the face; therefore it is not to be admitted to meat, or medicine".
Nevertheless, it is not infrequently made into a tea (from the garden herb) in country districts. "Pliny," says Evelyn, "reports Rue to be of such effect for the preservation of sight that the painters of his time used to devour a great quantity of it; and the herb is still eaten by the Italians as frequently mingled amongst their salads." Again, Gerarde relates that this herb grows most profitably under a fig tree. Country people boil its leaves with treacle, thus making a conserve thereof. These leaves are curative of croup in poultry. During the early part of last century it was customary for our Judges, when sitting at Assize, to have sprigs of Rue placed before them on the bench of the Dock as defensive against the pestilential infection brought into Court from gaol (then altogether neglected as to its sanitation) by the wretched prisoners. A quaint old rhyme says of the plant: -
"Nobilis est Ruta Quia lumina reddit acuta".
"Noble is Rue: it makes the sight of eyes both sharp and clear: With help of Rue, oh! blear-eyed man! thou shalt see far and near".
This is especially the case when the vision has become dim through over-exertion of the eyes. It was with "Euphrasy, and Rue "that the vision of Adam in Paradise was purged by the Angel, according to Milton. Other popular names for the plant are Herbe grass, Herbigrass, and Horby grass. In Lincolnshire countryfolk say it must be given only in the morning, because as the afternoon supervenes it becomes poisonous. "You know Herby grass is Herby grass in the morning, but Rue in the afternoon." Thornbury records the fact that in the England of Shakespeare's day "the tops were eaten with bread and butter of a morning to purify the blood".