OIL OF TURPENTINE. 887 



oil, however, is not identical with the essence, differing from it 

 in its optical properties, and is distinguished as camphilene 

 (Deville). The liquid hydrochlorate is of density 1.017, and its 

 composition is also expressed by C 20 H 16 + HC1. (Soubeiran, 

 Capitaine). 



It is difficult to decompose the hydrochlorate of turpentine 

 completely by an alkali ; a portion of it distils over and contami- 

 nates the oil thus obtained. M. Deville adds gradually to 

 essence of turpentine kept cold, a small quantity, about 9 vth 

 of oil of vitriol, so that the whole becomes deep red and viscid 

 after strong agitation, allows it to deposit for twenty-four hours, 

 and decants the thick liquid from a black deposit. This red 

 liquid, when heated, emits some bubbles of sulphurous acid, 

 becomes colourless, and is transformed into a mixture of two 

 oils, which he names terebene (from terebenthine), and colo- 

 phene. The former distils over first. Terebene has the same 

 composition and density as camphene, but differs from the 

 latter in its rotatory power on polarised light being equal to 

 nothing. By treating terebene by hydrochloric acid, Deville 

 obtained a new liquid, suh-hydrochlorate of terebene, of density 

 902 at 59, with a good deal of the odour of terebene itself; 

 its composition 2C 20 H 16 -f- HC1. A corresponding hydrobromate 

 of terebene was a colourless liquid, of density 1.021 at /5.2 

 (24 centig.); its composition 2C 20 H 16 H-HBr. The solid 

 hydrobromate of camphene, formed by the action of hydrobromic 

 acid on the essence is C 20 H ]6 -f HBr. It preserves, in common 

 with the solid hydrochlorate, the negative rotatory power of the 

 essence. The liquid hydrochlorate, prepared from the essence, 

 loses that property, and is, therefore, supposed not to contain 

 camphene but terebene, and named hydrochlorate of terebene. 

 When hydrochlorate of terebene is distilled with an alkali, it 

 gives an isomeric oil, terebilene, having the same relation to 

 terebene that camphilene has to camphene. Two corresponding 

 hydriodates of terebene have been formed. 



A very regularly crystallized substance has often been found in 

 old oil of turpentine, or in oil of turpentine left long in contact 

 with dilute nitric acid, which appears to be formed by the assi- 

 milation of the elements of water. Its composition is C 20 H 22 O 6 , 

 or represented as a hydrate of oil of turpentine C 20 H l6 -f6tIO. 

 (Dumas and Peligot). It is fusible about 302 (150 centig.), 



