THE ESSENTIAL OIL OF LEPTOSPERMUM FLAVESCENS. 179 



156° 0. at 10 mm. The three samples from different 

 distillations, after melting on the water bath, gave the 

 following specific rotations in chloroform solution, viz: — 

 Hill Top, 9/11/20, M.pt 81°C, 1*3775 grams in 10 ccs. 

 chloroform at 20° O. [a]„20° O. + 38'87° 



Ditto, 26/2/21, M.pt 81° C, 1*6480 grams in 10 ccs. 

 chloroform at 20° C. [a] D 20° C. +33*67° 



Blackheatn, 19/4/21, M.pt 79-80° 0., 1*6054 grams in 

 10 ccs. chloroform at 20° O. [o] D 20° O. +38*32° 



It is, therefore, identical with the bicyclic sesquiterpene 

 alcohol, eudesmol, a widely occurring constituent of the 

 oils of the Myrtacese. The high saponification number of 

 the acetylated oils is due to this alcohol. 



Determination of the Phenol, — The isolation and deter- 

 mination of this constituent, apparently new to science, 

 was described in a separate communication to the Society 

 on the 1st June, 1921, see pp. 49-51. 



Determination of Citral. — This aldehyde was separated 

 by agitation of the crude oil with a 35% solution of crystal- 

 lised sodium sulphite. The aqueous layer, after repeated 

 washing with ether, was treated with caustic soda solution, 

 and the liberated aldehyde separated. It varied in amount 

 from 0*25% to 0*75%. It possessed the usual well known 

 characteristic lemon odour and appearance of citral, and 

 was quite inactive when examined in the polarimeter. It 

 had:— Specific gravity, 15° O. 0*8972 

 Refractive index, 20° O. 1*4884 

 P napthocinchonic acid, m.pt 199-200° C. 



Summary, — The oil of Leptospermum flavescens (Smith) 

 consists essentially of the following bodies, viz: — Dextro- 

 rotatory eudesmol, eudesmene, aromadendrene, a and /3 

 pinene, leptospermol (phenol), together with small amounts 

 of citral and unidentified alcoholic bodies. 



