436 COMPOUND PRODUCTS. CHAP. I. 



It is obtained in a liquid state from incisions 

 made in the bark, and is somewhat bitter to the 

 taste. 



Copaiva, or Balsam of Copaiva. This resin is 

 obtained from the Copaifera officinalis^ a tree which 

 grows in South America. It exudes from artificial 

 incisions, having at first the consistence of oil, 

 but gradually becoming thick as honey. It is trans- 

 parent and of a yellow colour, with an agreeable 

 smell, but pungent taste. It is a combination of 

 resin and of volatile oil, which maybe separated by 

 distillation with water. It is employed also in 

 medicine. 



Dragon's blood. This resin is obtained from the 

 Draccena Draco, Pterocarpus Draco, and Cala- 

 mus Rotangy plants that grow in the East Indies 

 and in Spanish America. Its colour is dark red, 

 but it is without taste. Its fracture is glassy, and 

 its powder crimson. It comes into this country in 

 small masses wrapped in leaves, and is much used as 

 a tooth powder. 



Guaiac. This resin is the produce of the Guai- 

 acum officinale, a tree which grows in the West 

 Indies. It exudes spontaneously, or is driven out 

 in a melted state by means of the action of heat. 

 Its colour is green, with some transparency; its 

 consistency brittle; its fracture vitreous. It has 

 scarcely any taste and no smell ; but when thrown 

 on burning coals it exhales a fragrant odour. It 

 is used in medicine. 



