Guai'acum officina'le or G. Sanc'tum, Guaiac, Guaiac Resin, N.F. -- Zygophyllaceae. The resin of the wood, yielding not more than 15 p.c. of residue insoluble in alcohol; W. Indies, S. America. Small trees 6-9 M. (20-30 degrees) high, stem-bark ash-gray, striated, spotted; leaves paripinnte, yoked in pairs, evergreen; leaflets 2.5-4 Cm. (1-1 2/5') long; flowers large, blue; fruit 2-5-celled capsule; seeds black, red. Wood (Lignum Vitae): sap yellowish, heart brownish, heavier than water, sp. Gr. 1.30, hard, dense, touch, resinous, with heat--emitting balsamic odor; taste slightly acrid; in shop as raspings. Resin: in irregular fragments, large masses, tears, brown--greenish gray-brown on exposure; fracture with glassy luster, thin pieces translucent, reddish to yellowish-brown. Powder, grayish, becoming green on exposure; odor balsamic; taste slightly acrid; soluble in alcohol, ether, chloroform, creosote, solutions of alkalies, chloral hydrate T.S., sparingly in carbon disulphide, benzene; alcoholic solution with excess of chlorine water or tincture ferric chloride--blue, changing quickly to green; solvents: alsohol, acetone, chloroform; contains quaiaretic acid, guaiaconic acid (alpha-resin) 50-70 p.c., guaiac beta-resin 10 p.c., gum 4-9 p.c., guaiacic acid, guaiac-yellow, by dry distillation get guaiacol. Alterative, diaphoretic, expectorant, stimulant, antiseptic; rheumatism, gout, lumbago, syphilis, scrofula, amenorrhea, dysmenorrhea, diphtheria. Dose, gr. 5-30 (.3-2 Gm.); 1. Tinctura Guaiaci, 20 p.c. (alcohol), dose mv-60 (.3-4 cc.); 2. Tinctura Guaiaci Ammoniata, 20 p.c. (sp. ammon. arom.), dose, mv-30 (.3-2 cc.): Prep.: 1. Gargarisma Guaiaci Compositum, 10 p.c. + tr. cinch. co. 10, honey 20, pot. chloras 4, +; 3. Tinctura Guaiaci Composita, Dewees' Tincture of Guaiac, 12.5 p.c., + pot. carb. .6, pimenta 3.2 (diluted alcohol), dose, mv-60 (.3-4 cc.). Mixture (Br.), 2.5 p.c., 3iv-8 (15-30 cc.). Lozenge (Br.), 3 gr. (.2 Gm.), Syrup. G. Angustifo'lium; S. Texas, Mexico. Wood hard, heavy, splitting irregularly, yellowish-brown; sometimes substituted for the preceding.