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



from these." The specific rotatory power of the terpcne 

 boiling at 167° to 1G8° is [«]d = -10-9. 



14. The results of the vapour-density determination detailed 

 in paragraph 11 led us to look on the presence of a small 

 quantity of a higher-boiling liquid in this terpene (C15 Hsi?) 

 as probable. It might be supposed that the liquid boiling at 

 167° to 168° is really a mixture of the terpene of lower 

 boiling-point with about 4 per cent, of a terpene of the type 

 Ci5 H2.i (paragraph 11). Such a mixture — assuming the 

 Ci5 H24 terpene to have a specific gravity of 0*915, which is 

 about the mean of the densities of terpenes of this formula 

 as determined by Gladstone, and assuming that no condensa- 

 tion of volume occurred through mixing the two liquids — 

 would have a specific gravity of about 0*865 at 15° ; but the 

 liquid boiling at 167° to 168° has a specific gravity of 

 0*8866 at 15°. The assumption that this liquid is a mixture 

 of the 157° terpene and such an amount of a C15 H24 terpene 

 as would be in keeping with the result of the vapour-density 

 determination, is therefore not borne out by the actual specific 

 gravity of the liquid. "We are rather inclined to believe that 

 sage-oil contains two terpenes of the formula Cio Hie, differing 

 in physical properties, and perhaps a small quantity of a ter- 

 pene of higher molecular weight. 



The physical as well as the chemical properties of the 

 terpene boiling at 157° leave little doubt of the identity of this 

 compound Avith terebenthene, the terpene obtained from 

 French oil of turpentine. The terpene boiling at 167° to 168° 

 Ave cannot regard as perfectly pure. In a letter to one of us, 

 Dr. Gladstone says, " Thehghter terpene is practically iden- 

 tical with that from turpentine in refraction and dispersion, 

 as well as in boiling-point and specific gravity. The heavier 

 one, with the higher boiling-point, has a low^r refractive 

 energy than any terpene I have examined. Is it pure?" 



[nvestigations carried out on larger quantities of oil can 

 alone enable us to make positive statements regarding the 

 composition of the higher terpene. 



15. Treatment of the terpene boiling at 167° to 168° with 

 strong sulphuric acid, and distillation of the product in steam, 

 in the manner described in paragraph 8, resulted in the pro- 

 duction of about 8 per cent, of a liquid which gave the reactions 

 for cymene, and on oxidation with chromic liquor yielded 

 terephthalic and acetic acids. The polymerized residue yielded 

 no solid oxidation-product on treatment with chromic liquor. 



The terpene itself when oxidized, yielded a considerably 

 larger quantity of terephthalic acid than was obtained from 

 the 157° terpene. 



