GALLIC ACID 567 



the glycerite, tannic acid may be applied advantageously to 

 the skin in moist eczema, and as a remedy for frost bites. 

 It is a useful application for sore and cracked teats. The 

 mouth is painted with the glycerite for the cure of ulcerative 

 or apthous stomatitis. The same preparation is injected into 

 the ear in otorrhoea of dogs, and into the vagina to arrest 

 vaginitis and leucorrhoea. Pure tannic acid is an excellent 

 •agent when dusted upon raw surfaces, ulcers, and sores ; and 

 to stop bleeding in slight wounds. An aqueous solution is 

 useful in leucorrhoea (2-5 per cent.), in eczema (5-10 per 

 cent.), as a high enema in dysentery (1 per cent.), and to kill 

 ascarides (1-2 per cent.) in the rectum. A one per cent, 

 aqueous solution is sometimes utilized as an iuhalation in 

 subacute laryngitis, tracheitis, and bronchitis. Powdered 

 opium and nutgall ointment (1-14), or glycerite of tannin, 

 are serviceable in haemorrhoids and rectal fissures, ulcers, 

 or prolapse of the rectum. 



Uses Interned. — Tannic acid is exhibited in powder or 

 solution to arrest bleeding in the stomach. It is a good 

 astringent in diarrhoea and haemostatic in intestinal haemor- 

 rhage, given in ball or pill, and often with opium. Tannic 

 acid is an antidote to alkaloids, metallic salts, and tartar 

 emetic, forming comparatively insoluble tannates, which 

 should be removed if possible by evacuation of the stomach. 



AciDUM Gallicum. Gallic Acid. HC^H.Os 4- HjO. 

 (U. S. & B. P.) 



Synonym, — Acide gallique, Fr.; gallussaure, G. 



An organic acid, usually prepared from tannic acid. 



Derivation. — Made by the exposure of paste of nutgall 

 and water to the air for a month, when tannic acid under- 

 goes hydration (tannic acid) HC,,HA + H,0 = 2 HC.HA 

 (gallic acid). The liquid is then expressed from the paste 

 ^ and the residue is boiled with distilled water and filtered, 

 when hot, through animal charcoal. Gallic acid crystallizes 

 ont from the filtrate. 



