This section is from the book "An Experimental History Of The Materia Medica", by William Lewis.
Cynoglossum Pharm. Paris. Cynogloffum majus vulgare C. B, Lingua canina. Cynogloffum officinale Linn. Hounds tongue: a biennial plant; producing, the first year, large, soft, tongue-shaped, long-pointed leaves; the second year, a thick, branched stalk, with narrower and shorter-pointed leaves joined to it without pedicles; bearing, on the tops of the branches, dark purplish flowers, each of which is divided into five segments, and followed by four flat rough seeds: the root is oblong, thick, of a dark brown or blackish colour on the outside, and white within. It is found wild in shady lanes and uncultivated grounds, and flowers in June.
The roots of hounds tongue are very juicy, and liable to grow mouldy in drying: Such as are produced in moist grounds have, when fresh, a rank, though not very strong smell, like that of the narcotic plants, which in drying is in good measure dissipated: those, which are the produce of dry grounds, have scarcely any smell (a). On the organs of taste, they make no great impression.
The medical effects of these roots are some-what doubtful. It has been generally supposed that they are narcotic; by some, that they are virulently so. The argument for their innocence (b), from the frequent and safe use of a pill, to which they still give name in foreign pharmacopoeias, appears unfair; the quantity of the hounds tongue root, in a dose of that opiate pill, being only about a grain; whereas the root by itself is ordered, in decoction, to the quantity of an ounce, in catarrhs, coughs, diarrhoeas, dyssenteries, and hemorrhagies.
(a) Hermann, Cynosura mat. med. edit. Boeder. torn. 1. p. 178.
(b) Geoffroy, Mat. med. iii. 395. Ray, Hift. plant, i. 490.
The leaves of the plant are supposed to be of the same quality with the roots: to the smell, they are stronger and more disagreeable. Fuller reports, that he has used a syrup of the juice a multitude of times, and could never find it to cause deep, or to be in the least virulent; and that he had often experienced it to be a great remedy, second to none, against hot, sharp, thin, catarrhous humours, and a cough occa-sioned thereby. Neither the leaves nor the roots are ever made use of in practice; and the colleges, both of London and Edinburgh, have now rejected the plant from their catalogue of officinals; all the good effects, which the accounts of those who have recommended it afford grounds to expect from it, being obtain-able, without suspicion of malignity, from the produces of the poppy.