Common Tansy. Nat. Ord. Com-positAe. Linn. Syst. Syngenesia Superflua. Hab. Great Britain, &c.

Med. Prop. and Therap. Uses. The leaves are tonic and anthelmintic in doses of gr. xx. - gr. lx. They are best given in infusion (gr. cxx. ad Aq. Oj.). They were formerly extolled as a means of diminishing the frequency and violence of attacks of Gout, but are now abandoned, except as an occasional vermifuge against Lumbrici. in which respect they are said to be effectual. The small activity which they possess depends upon a volatile oil and a bitter extractive.

2701. Tannic Acid

Acidum Tannicum. Tannin. Is chiefly obtained from Galls, but exists largely in Catechu, Rhatany, and other vegetable astringents. Comp.

C54H22O34.

* U. S. Disp., p. 1492. Dublin. Quart. Journ. of Med., Feb. 1S55.

Dr. Clarke, Essays Phys. and Lit., vol. iii. p. 438.

Med. Prop. and Action. Powerful astringent, in doses of gr. ij. - gr. iij. twice a day, in chronic cases; gr. v. - gr. xx. in urgent cases, such as acute hAemorrhage, &c Dr. Alison * regards it also as a valuable peptic and nervine, and considers that it possesses the property of retarding the growth of tubercle, and malignant disease. Anti-periodic powers have also been assigned to it by M. Leriche. It may be given either in pill or in solution. It possesses many advantages for administration, is not very bitter, is free from odour, does not induce nausea, is perfectly safe, may be continued for mouths without any ill effects, may be given at all hours, before or after meals, and it may be employed at the same time with Iron, Cod Liver Oil, bitters, &c. Dr. Garrod, on the authority of Wohler and Frerichs, states, that when Tannic Acid is taken into the system, it undergoes a change, and appears in the urine as Gallic and Pyro-gallic acids, and a humus-like substance; and he consequently concludes that a given quantity of Tannic Acid must be inferior, as a remote astringent, to the same weight of Gallic Acid; that the former acts more powerfully as a local astringent, and the latter is more effectual as a remote one. He states that, from the presence of the humus-like matter, the urine of patients taking Tannic Acid sometimes becomes quite dark coloured, especially after it has been exposed to the air for a short time. Gelatine is not precipitated by the urine of patients taking Tannic Acid, showing the absence of that acid, but it strikes black with Persalts of Iron, from the presence of Gallic Acid.§ Externally, it may be applied in the form of lotion or wash (gr. ij. - gr. iij., Water fl. oz. j.), or ointment (gr. iv. - gr. v., Lard oz. j.), or in the form of fine powder.

Offic. Prep. 1. Suppositoria Acidi Tannici (Tannic Acid grs. xxiv.; Glycerine xx.; Prepared Lard q. s.; White Wax q. s. Mix grs. lxxx. of the Lard and grs. xl. of the Wax in a water-bath, and when nearly cold add the Tannic Acid previously mixed with the Glycerine. The mass when solidified is to be divided into twelve cones, which are to be dipped in a mixture of three parts of Melted Wax and eight of Melted Lard.