102 H. G. SMITH. 



are interesting and the want of material has alone prevented me 

 completing their investigation at this time, but I hope to continue 

 the research later. The nitro-compound is also worthy of further 

 inquiry. 



On fusing eudesmol with potash at 180° C, the volatile acid 

 obtained on acidifying with sulphuric acid and distilling was acetic 

 acid. No iso-butyric acid was detected. 



Theoretical Considerations. 

 The isolation of eudesmol from several members of the "globulus 

 group" of Eucalypts, (those species whose oils are rich in eucalyptol 

 at time of distillation), the natural alteration of the eudesmol 

 fraction from oils like that of E. inacrorhyncha with the corres- 

 donding formation of eucalyptol, and the other facts described in 

 the body of this paper, show eudesmol to be intermediate in the 

 formation of eucalyptol in Eucalyptus oils. 



Eudesmol has a formula C 10 II lt; O, is isomeric with camphor, and 

 contains two atoms of hydrogen less than eucalyptol. 



The ease with which eudesmol forms a di-bromide as an additive 

 compound (attempts to form a higher bromide were not successful), 

 indicates that the molecule is unsaturated, but that the linking must 

 be different from the double linking of the terpenes is shown by 

 eudesmol not forming a nitrosochloride. The pinenes of Eucalyptus 

 oils readily form nitrosochlorides. Eudesmol not reacting with 

 phenylhydrazine indicates that the oxygen atom is not ketonic, 

 but that it is combined in the molecule in some other way. The 

 non-success in all attempts to introduce hydrogen atoms into the 

 eudesmol molecule by ordinary methods, and its inertness to the 

 action of sodium generally, makes it appear probable that the 

 oxygen atom is combined to more than one carbon atom. It may 

 be that cymene plays some part in the formation of eudesmol. 

 Cymene has been shown to occur in the oil of E. globulus 1 and 

 thus in other Eucalyptus oils, because Eucalyptus globulus is only 

 one member of a class whose oils are identical in composition. 



1 Faust and Homeyer, Ber. vn., 1429. 



