EBSINOUS PRODUCTS — CAOUTCHOUC. 169 



of the fruit ; and oil of neroli, from orange flowers. A second series 

 contain oxygen in addition, as oil of cinnamon, from Oinnamomum 

 zeylanicum ; otto or attar of roses, from various species of Eose, 

 especially Eosa centifolia ; oil of peppermint, from Mentha viridis ; 

 oU of caraway, from Oarum Carui ; oU of cloves, from OaryophyHus 

 aromaticus. Oils of this kind are procured from many Labiatse, as 

 species of Lavandula, Origanum, Eosmarinus, Thymus ; and from the 

 fruit of Umbelliferse, as species of Anethum, Fceniculum, Coriandrum, 

 Cuminum, Petroselinum, Pimpinella; and from some Compositse, as 

 species of Anthemis, Pyrethrum, and Artemisia. A third series have 

 also sulphur in their composition, and have a peculiar pungent, often 

 aJQiaceous smeU, with an acrid burning taste, as oU. of garlic, and of 

 onion, procured from the bulbs of Allium sativum and Cepa ; oU. of 

 assafoetida, from Narthex Assafoetida ; and oU of mustard, which is 

 obtained from the seeds of Sinapis nigra when macerated in water by 

 a kind of fermentation induced by the action of a nitrogenous body, 

 myrosin, on a substance called myronic acid, or myronate of potash. 

 A simUar oil exists in many Cruoifer*, as in AUiaria officinalis, 

 Armoracia rusticana, and Cochlearia officinalis, and in several Um- 

 belliferse, yielding gum-resin, as Opoponax, Ferula, Galbanum, etc. 

 Many of the essential oUs deposit a solid crystalline matter, called 

 Stearoptene, allied to camphor. This latter substance, which consists 

 . of carbon, oxygen, and hydrogen, is procured from Camphora offici- 

 narum, a native of Japan and India. There is also another kind of 

 camphor, produced in Borneo, from Dryobalanops Camphora. 



Eesinous Peoduots. — The mUky and coloured juices of plants 

 contain frequently resins mixed with volatUe oUs, in the form of 

 balsams, besides a quantity of caoutchouc. The resinous substances 

 found in plants are either fluid or solid. The former may be illus- 

 trated by Balsam of Tolu, procured from Myroxylon toluiferum; 

 Balsam of Peru, from Myroxylon Pereirse ; Balsam of Copaiba from 

 various species of Copaifera, especially Copaifera officinalis and mul- 

 tijuga ; Carpathian Balsam, from Pinus Pinea ; Strasburg turpentine, 

 from Abies pectinata (sUver fir) ; Bordeaux turpentine, from Pinus 

 pinaster ; Canada Balsam, from Abies balsamea (Balm of Gilead fir) ; 

 Chian turpentine, from Pistacia Terebinthus, etc. The latter may be 

 illustrated by common resin or Colophony, and Burgundy pitch, from 

 Pinus sylvestris ; Mastich, from Pistacia Lentiscus ; Sandarach, from 

 Callitris quadrivalvis ; Elemi, from several species of Amyris ; Guaiac, 

 from Guaiacum officinale ; Dragon's-blood, from Dracaena Draco, and 

 Calamus Draco ; Dammar, from Dammara austrahs and orientalis; 

 Labdanum, from Cistus creticus, and other species ; Tacamahaca, from 

 Calophyllum Cadaba, and from Elaphrium tomentosum ; Eesin of Jalap, 

 from Exogonium Purga; Storax, from Styrax officinale; Benzoin, 

 from Styrax Benzoin; Copal, from Vateria indica, etc. Lac, from 



