GUAIACI. RESINA GUAIAC. 59 



tains also an ethereal oil, one or two per cent. Ci^Hj,, 

 made up for the most part of pinene. There is a bitter 

 stuff extracted by water. 



Other Kinds and Adulterations. — Pistacia TerehinthincB, 

 from North Africa, yields a mastiche, Chios turpentine, 

 which closely resembles ordinary mastiche. It has the 

 same turpentine taste, but is free from the bitter principle 

 of mastiche, and ip more completely soluble in alcohol. A 

 variety of the species also gives a mastiche. Bombay 

 mastiche is by Fliickiger regarded as allied with the pre- 

 vious type This mastiche resembles Chios mastiche 

 closely, is soluble in acetone, rotates light to the right, 

 is generally less yellow and more opaque. 



GUAIACI RESINA. GUAIAC. 



The resin of the wood of Guaiaciim officinale, Linn6. 

 The heart wood of Guaiaciim officinaley a tree indigenous 

 to the West Indian Islands and the northern coast of 

 South America, contains 15 to 30 per cent, of resin, and is 

 the chief source of guaiac resin. It may be obtained 

 from deep incisions in the bark, but the usual method of 

 collection is that of extraction by burning. The resin lies 

 in nearly all the elements of the wood, it being particularly 

 rich in the vessels, which are sometimes completely filled. 



In the market it appears in irregular pieces, reaching 

 one to one and one-half inches in diameter, the surface 

 somewhat watery, greenish to brownish, dusty. As it is 

 usually mixed with portions of the charred wood its 

 fractured surface will vary considerably, being brownish, 

 greenish, glassy or dirty, according to its purity. Small 

 pure pieces or splinters are transparent, shining, greenish 

 or brownish in color. Freshly powdered the color is 

 grayish brown. Later by oxidation in the air the powder 

 becomes greenish in color. The odor on heating is 

 aromatic. The taste is at first sweet and bitter, later 

 sharp, irritating, and astringent. 



