GUAIACUM 



259 



CONSTITUENTS. Guaiacic acid, /3-resin (11.75 P er cent.), and guaiac yel- 

 low, C2oH 20 O7, soluble in milk of lime; guaiaretic acid, C2oH 2 404, 

 11.15 P er cent.; guaiaconic acid, 50 per cent., and gum and ash in 

 small quantity. Guaiacene, guaiacol, cresol, and pyroguaiacin are 

 obtained by dry distillation. The coloring matter crystallizes in 

 pale yellow or quadratic octahedra having a bitter taste. Ash, not 

 exceeding 4 per cent. 



The so-called "guaiacum oil" is obtained by boiling guaiacum 

 resin with solution of sodium carbonate, allowing to cool, filtering, 



FIG. 141. Guaiacum Cross-section of wood. R. Medullary rays, composed of one, two, and 

 three ranges of cells. V. Closed vessels. F . Ligneous fibers, very much developed and forming 

 concentric zones. 



saturating the filtrate with carbon dioxide, again filtering, extracting 

 the oil with ether, and allowing the solvent to evaporate. The 

 product is soluble in water, alcohol, and ether. From the alkaline 

 liquid acids precipitate the yellow coloring matter ("guaiacum yel- 

 low"), which imparts a blue color to strong sulphuric acid. 



The blue color which guaiacum resin produces with certain oxidiz- 

 ing agents is due to an oxidation product of guaiaconic acid. 

 ACTION AND USES. Stimulant, diaphoretic, and alterative; also a mild 

 purgative. Dose: 5 to 30 gr. (0.3 to 2 Gm.). 



OFFICIAL PREPARATIONS. 



Tinctura Guaiaci (20 per cent.), Dose: 30 to 60 IJR (2 to 4 mils). 



Tinctura Guaiaci Ammoniata (20 per 



cent.) 30 to 60 itjj (2 to 4 mils). 



