CAJUPUT. 451 



— 6^, a crystalline mass can be separated. The purified crystals 

 appear to consist of eucalyptol. They melt at 1*^ to a liquid of 

 camphoraceous odour, optically inactive and boiling at 175^. The 

 sp. gr. of this eucalyptol is 0-930 and its vapour density o-28 

 (calculated 5-34 for CioHj^O). Treated with very dry hydro- 

 chloric acid vapour, an unstable crystalline compound is formed, 

 having the composition (C^s H^g 0)0 H CI. AVater instantly 

 decomposes this into its original components. The liquid from 

 which the crystals have been separated has a lemon odour, and is 

 apparently a mixture of eucalyptol and a hydrocarbon of the 

 fonnula C^o H-^.j. Its density is O'OIT, and optical activity 

 — 4'-^10'. The fraction distilling above 180^ forms a syrupy liquid, 

 boiling about 220°, and yielding a small proportion of crystals at 

 — 50*^. By using one of these crystals as the starting point, 

 crystallisation may afterwards be readily induced in the remaining 

 liquid, taking place rapidly at the ordinary temperature. The solid 

 substance, dried in vacuo, only melts when a temperature of about 

 30° is attained, the syrupy liquid then formed having the formula, 

 Cjo H;^8 0, boiling at 218°, and presenting all the characteristics 

 assigned by Bouchardat and Lafont to the terpineol synthesised by 

 them*, except that it is feebly laevo-rotatory, — 2°10', whilst the 

 synthetic terpineol was inactive. Finally, there remains in the 

 apparatus after distillation a small quantity of resinified matter of 

 a greenish colour. 



Neglecting the secondary products, Bertrand arrives at the 

 conclusion that the essential oil of M. riridifolia consists, apart 

 from the dextro-rotatory terpene, CioHi,;, a mixture of three 

 bodies, eucalyptol, a hydrocarbon, probably " citrene " {sic), boiling 

 at 175°, and a terpineol. This composition is identical with that 

 of the terpinol of List,f obtained by heating wdth acidulated water 

 the terpene C ^ q H j ,. 2 H ^ 0, resulting from the spontaneous 

 dehydration of terpenes, C\o Hj^, the natural product being thus 

 readily imitated artiticially in the laboratory by extremely simple 

 reactions. 



Referring also to the fact that Bouchardat obtained a " citrene " 

 by heating the valerylene derived from amylic alcohol, the author 

 states that he has found it possible to extract small quantities of 



* Comptes Rendus., cii., p. 1555. 



t Comptes Rendus, civ., p. 996, and cvi., p. 663. 



