EUCALYPTUS. 



245 



derived, also the more these eucalyptols from various sources 

 become identical, and lose traces of odour by which they were 

 distinguished.* 



Besides being found in many eucalyptus oils, such as E. glolulus, 

 D. clumosa, E. cneorifolia D.C., E. oleosa, E. amygdalina, E. 

 BaiUyana and E. microconjs, &c., eucalyptol has been detected in 

 the following essential oils : — 



As cineol has been isolated from such a number of oils of 

 different odours, and as its physical characters are so altered by 

 the presence of small quantities of other bodies, it has in many 

 cases been considered a distinct substance and received a different 

 name, as the eucalyptol of eucalyptus oils, and caju2ndol of 

 cajuput oil. 



Cineol (or eucalyptol) is readily converted into dipentene 

 derivatives by the action of halogen acids, but when dry hydro- 

 bromic acid is passed into a dry ethereal solution of cineol, a white 

 crystalline hydrobromide C\o H^^ H Br. melting at 56^- 

 57°C., and decomposing immediately with water, is deposited. 

 The formation of this hydrobromide and of cineolic acid when the 



* For description of phellandrene and names of oils containing it, see 

 "Elemi." 



