342 Messrs. M. M. Pattison Muir and S. Sugiura on 



however, take place with so groat facility as has been noticed 

 in the case of other terpenes of higher boiling-points *. 



10. About 25 cubic centims. of the tei'pene boiling at 

 157° was subjected to the action of two litres of boiling 

 chromic liquor, containing 10 per cent, of potassium dichro- 

 mate, and sulphuric acid sufficient to saturate the bases 

 present. After 37 hours the boiling was stopped, and the 

 small quantity of solid matter which had been produced was 

 collected, washed with hot water, dissolved in boiling ammonia, 

 and reprecipitated by hydrochloric acid. It gave the reactions 

 of terephthalic acid. The liquid, when distilled, showed the 

 reactions for acetic acid. 



The residue, after polymerizing the terpene with sulphuric 

 acid in the manner described in paragraph 8, and distilling 

 in steam, was boiled for some days in chromic liquor. No 

 solid oxidation-product was obtained. 



Wright t has shown that the terpene from orange-peel oil, 

 boiling at 178°, yields no cymene when treated with strong- 

 sulphuric acid and distilled in steam, nor does it yield a trace 

 of terephthalic acid on oxidation. The same chemist X has 

 also shown that oil of turpentine yields cymene by treat- 

 ment with sulphuric acid &c. According to some chemists 

 terephthalic acid is one of the products of the oxidation of oil 

 of turpentine; according to others this acid is not produced on 

 oxidizing that oil. The fact that, when cymene had been 

 removed from the liquid portion of sage-oil boiling at 157°, 

 the residue yielded no terephthalic acid on oxidation, although 

 the original liquid (before treatment with sulphuric acid &c.) 

 did yield this acid, seems to point to the cymene which was 

 present as the source whence the terephthalic acid was 

 derived. 



The varying results obtained in the oxidation of oil of 

 turpentine were probably due to the varying composition of 

 the specimens employed; when free from cymene, this oil 

 appears to yield no trace of terephthalic acid on oxidation § . 



11. That portion of the oil which, after treatment with 

 sodium and distillation, boiled from 166° to 168°, was frac- 

 tionated until the greater part boiled constantly from 167° to 

 168° (thermometer surrounded with vapour; barometer 760 

 millims.). The liquid so obtained had a somewhat more pro- 

 nounced odour of sage than the fraction which boiled at 157°; 

 it was perfectly colourless. 



* See Wriglit, ^' On Isomeric Terpenes," Cliem. Soc. Jouni. [21 xi. 

 p. 694. 



t Cliem. Soc. Journ. [2] xi. p. 552. | Loc. cit. 



§ See W. Oaiieton Williams, Ber. deut. Chem. Ges. v. 1094. 



