This section is from the book "An Experimental History Of The Materia Medica", by William Lewis.
Alliaria C. B. Erysimum alliaria Linn. Sauce-alone, or jack-by-the-hedge: a plant, with roundish, or heart- shaped, slightly indented leaves; and firm upright stalks; on the tops of which, and in the bosoms of the leaves, come forth clusters of tetrapetalous white flowers; followed by oblong bivalvous pods, full of black seeds. It is biennial, grows wild in hedges, and flowers in May.
The leaves of alliaria have a moderate acrimony, and a strong flavour greatly resembling that of garlic or onions: they give the same kind of durable taint to the breath, as those roots; and have been used for the same culinary purposes. They lose greatest part of their smell, and a little of their taste, on being moderately dried: after keeping for some months, the taste, as well as smell, seemed to be wholly loft: the leaves, on being chewed, proving merely mucilaginous. The juice, expressed from the fresh leaves, is strongly impregnated with their active matter, but loses greatest part of it on being inspiffated to an extract with the gentlest warmth: in its liquid state, duly secu-red from the air, it may be kept uninjured for many months. On distilling the fresh herb with water, there arises a small portion of essen-tial oil, which tastes and smells exceeding strongly. Great part of the virtue of the plant arises also in evaporation with rectified spirit; an extract, made by this menstruum, having little taste or smell, though the tincture, before the infpiffation, has a strong flavour of the alliaria. This herb appears, therefore, to differ from garlic, and agree with onions, in the volatility of its active principles.
Alliaria, taken internally in any considerable quantity, frequently excites a sweat, which is impregnated with its smell (a): it stands recommended as a very powerful diaphoretic, and diuretic, as a deobstruent in asthmatic disorders, and externally as an antiseptic, in gangrenes and putrid ulcers. Boerhaave informs us, that he cured a gangrene of the leg, arising from a neglected fracture and contusion, by applying the leaves of alliaria bruised with wine (b).