152 A RESEARCH ON THE EUCALYPTS OF TASMANIA 



= r4715. The saponification number for ester and free 

 acid was 34' 3"^, and the ester consisted mostly of geranyl- 

 acetate. The oil contained the paraffin-like substance in 

 slightly greater amount than the Hobart specimen. 



The Stearoptene. — When the crude oils of both consign- 

 ments were dissolved in a large excess of 80 per cent, 

 alcohol, a copious flocculent substance separated. The tem- 

 perature of the solution was 18° C. It was filtered through 

 a hardened filter, washed with alcohol, and the solid fat- 

 like substance melted on the water bath to separate adher- 

 ing water and alcohol. The amount of crude material 

 thus obtained from the oil of the Hobart sample was equal 

 to 0*764 per cent., and from the Little Swanport material 

 0'816 per cent. This method naturally wasted the oil, as 

 only such a small amount of the stearoptene was present. 

 The portion of the oil distilling above 280^ C. became 

 semi-solid when cold ; this was boiled in alcohol, filtered 

 boiling hot, and the process repeated three times. On 

 cooling, the substance separated in flocks. After standing 

 some time it was filtered off and boiled in acetic ether, 

 which was found to be a good solvent for the purpose ; on 

 cooling, the substance separated, most of the impurities 

 remaining in solution. The stearoptene was but little 

 soluble in cold acetic ether, but readily in hot. The 

 crystalline fat-like substance was then boiled in alcohol 

 with a little animal charcoal, and filtered hot. In was 

 finally dissolved in chloroform and precipitated by the 

 addition of alcohol. When thus obtained it differed in no 

 respect from the corresponding material precipitated 

 directly from the oil by alcohol. 



When finally purified the stearoptene was perfectly 

 white, of a paraffin-like nature, without odour, easily 

 melted, and burnt away identically in odour and manner 

 with ordinary paraffin when similarly heated and ignited. 

 The melting-point was 55 to 56° C. determined by the 

 capilliary tube method in water, and in other ways. 



Under the microscope it was seen to be crystalline, and 

 when melted on glass and allowed to slowly cool, the 

 crystals polarised well in bright colours ; but these crystals 

 were not very symmetrical, but vermiform, often tending 

 to the shape of the letter S. When dissolved in carbon 

 tetrachloride, and bromine dissolved in the same substance 

 added, the colour was not removed; it was thus saturated. 

 Concentrated sulphuric acid had no action upon it in the 

 cold, nor did the usual oxidising mixture of potassium 

 bichromate in sulphuric acid act upon it in the cold, and 



