CONSTITUENT OF PEPPERMINT ODOUR IN EUCALYPTUS OILS. 141 



Molecular value. 

 1*1816 gramme in 27 3 grammes of glacial acetic acid gave a 

 depression in the freezing point of 1-085 degrees ; the molecular 

 value from this is 155. 

 O 10 H 18 O = 154. 



The crystalline substance formed on reduction. 

 On treating a solution in alcohol with metallic sodium, and 

 afterwards adding water, the thick oily substance which separated 

 was seen, after some time, to contain crystals. The aqueous 

 portion was removed and the oily mass treated with slightly 

 diluted alcohol in the cold. The crystals were but slightly acted 

 upon and it was thus possible to remove the adhering oily 

 impurities by dilute alcohol alone. That the crystals can be thus 

 purified, was seen by the fact that as thus obtained, they melted 

 at the correct temperature. The crystals are but slightly soluble 

 in ether, so that they can be thus purified also. The crystals were 

 found to be exceedingly soluble in chloroform from which on 

 evaporation oblique needle crystals were obtained. The best 

 method of purification was found to be to remove all adhering 

 impurities by alcohol and ether, drying, and afterwards dissolving 

 in chloroform, filtering, and allowing to crystallise. The crystals 

 were colourless, they were slightly soluble in acetic ether, insoluble 

 in acetone, and insoluble in alkalis. 



The melting point was 155 - 156° C. ; the substance did not 

 decompose on melting, and on cooling crystallised very finely in 

 long prisms of radiating crystals, which polarised exceedingly 

 well. Its slight solubility in both alcohol and ether may be 

 characteristic. 



Determination of the alcohol infraction 227 — 240° C. 

 An attempt to isolate an alcohol from this fraction with phthalic 

 anhydride was not successful, no alcoholic substance being obtained. 

 A portion of the oil of this fraction was then boiled for three 

 hours with acetic anhydride and anhydrous sodium acetate, treat- 

 ing in the usual way and saponifying the product, 1*3236 grammes 

 of the oil thus obtained was heated half an-hour with 10 cc. 



