254 ECONOMIC BOTANY. 



ranean region, furnishes the resin, Mastic. The name of 

 the shrub is Pistacia lentiscus ; it belongs to the Cashew 

 family {Anacardiacece). Nearly all the Mastic of com- 

 roerce comes from the island of Chios, where a variety Qvar. 

 chia) of the Pistacia lentiscus is cultivated. Sometimes 

 the resin flows out spontaneously, and hardens in drops on 

 the twigs. That from the twigs is better than that from 

 the trunks ; the latter are cut with a knife from the ground 

 up as high as the branches, and the resin flows out on flat 

 stones laid at the base of the tree. It is removed after 

 three or four weeks, and this method of collecting it is 

 followed about two months in a season. The amount 

 yielded by each tree is from eight to ten pounds. The 

 resin is a secretion, and occurs in special resin-canals in 

 the inner cortex. Its color is yellowish or greenish, and 

 more or less cloudy. The odor is similar to that of Galba- 

 num; in hardness it is between Damar and Sandarac; it is 

 heavier than water (specific gravity 1.04-1.07). Some of 

 its important constituents are mastic acid (eighty to ninety- 

 one per cent), mastacin, and a trace of volatile-oil. It is 

 used in the manufacture of fine varnish. 



222. Sandarac is from Callitris quadrivalvis, a small 

 tree found in the northwest mountains of Africa. It is a 

 member of the Pine family (ConifercB). The wood is 

 colored, hard, takes a fine polish, and is, therefore, esteemed 

 in cabinet-work. The resin flows after incisions are made, 

 also spontaneously from twigs and stems. It occurs in the 

 cortex, and is probably a true secretion. The color of the 

 Sandarac varies from a yellowish to a reddish-brown, it is 

 harder than Mastic, and has about the same specific gravity 

 (1.05-1.09). It has a vitreous lustre when a fresh surface 

 is exposed. The odor is weak, aromatic, and the taste 



