Mr. J. Cockle on the Correlations of Analysis. 531 



current of hydrogen to near its boiling-point until no more 

 camphor sublimes, and then rectifying. When pure, camphrene 

 is a yellowish limpid liquid, of a pleasant aromatic odour and 

 sharp taste. Its specific gravity is O9014, and it boils at 230° 

 to 235° C. Its formula is G 9 H 14 0, and is the same as that of 

 phorooe*, as is also the vapour-density. But the two substances 

 are only isomeric, as Sch^anert has shown by comparing the 

 action of different agents on them. "When phorone is treated 

 with anhydrous phosphoric acid, the hydrocarbon cumole, € 9 H 12 , 

 is produced^; by the same treatment camphrene also yields a hy- 

 drocarbon of the composition of cumole, but boiling at 30° lower, 

 and therefore not identical with it. By the action of nitric acid 

 phorone is converted into a resin ; camphrene is also acted on by 

 nitric acid, and yields a resin which contains a new bibasic acid, 

 camphrenic acid, G 9 H 8 O 4 , the formation of which mav be thus 

 expressed : 



€ 9 H 14 O + 12NH0 3 =G 9 H 8 O 4 + 9H 2 + 12NO 2 . 



Camphrene. Camphrenic 



acid. 



The salts of this acid are amorphous. 



By the action of pentachloride of phosphorus on camphrene, a 

 chloride of camphryle, G 9 H 13 CI, is obtained. It is a colourless, 

 transparent, refringent limpid liquid, with a pleasant aromatic 

 smell, and a somewhat bitter sharp taste. It differs from chlo- 

 ride of phoryle produced by the action of pentachloride of phos- 

 phorus on phorone, in its higher boiling-point and its greater 

 specific gravity. 



By placing sodium in camphrene mixed with pure benzole 

 until no further action took place, and then adding iodide of me- 

 thyle, distilling, and repeatedly pouring back the distillate on 

 the residue in the retort, a body, rnethylcamphrene, was obtained, 

 which after appropriate purification constitutes a pleasant, 

 ethereal, aromatic, limpid liquid, the formula of which is 

 G 9 H 13 (G H 3 0). Acetylcamphrene was similarly obtained. 



LXXII. Correlations of Analysis. 

 By James Cockle, M.A., F.R.A.S., F.C.P.S. #c.f 



1. r\ENOTING differentiation by an accent, so that 



let us define 



* Phil. Mag. S. 4. vol. xiii. p. 188. 

 t Communicated bv the Author. 



2 N2 



