AUSTRALIAN MELALEUCAS AND THEIR ESSENTIAL OILS. 205 



on porous plates to dry. When the oil had been absorbed 

 from the first precipitate, it was again treated in the same 

 way. By repeating the process several times the oily 

 portion was eventually entirely removed. The material 

 thus obtained was recrystallised repeatedly from alcohol, 

 from acetone, and finally from petroleum ether. A product 

 of constant melting point was thus obtained. Unfortunately 

 a considerable amount of the crystalline substance had been 

 lost by the continued absorptions. After the final purifica- 

 tion from petroleum ether, the substance was snow-white 

 and granular in appearance. The odour was but slight, 

 somewhat indefinite, and with no indication of a hyacinth- 

 like odour. The melting point was 72*5° C. This was best 

 taken by the open capillary tube method. A portion was 

 melted at the lowest possible temperature and then drawn 

 into the tubes. It remained twenty-four hours to com- 

 pletely crystallise, and 6 mm. of the column was retained. 

 The heating was in water, and the melting point taken at 

 the instant when the substance commenced to rise in the 

 tube. The specific rotation was determined in absolute 

 alcohol at 20° C, using sodium light, it was [a] D + 36*99°. 

 The percentage of active substance was 11*003. 



It sublimed somewhat readily in acicular crystals, and 

 was unaltered, the sublimate melting at the same temper- 

 ature as the original substance. When melted, it had a 

 tendency to remain for some time in a state of superfusion; 

 the crystallisation then took place in circular radiating 

 masses which continued to grow until the whole was 

 crystallised. It was readily soluble in acetic acid, chloro- 

 form, carbon tetrachloride, alcohol, ether, acetic ether, 

 acetone and organic solvents generally, crystallising again 

 in radiating rosettes when the solvent had evaporated. 



The formula is C ao H ]8 derived from the following deter- 

 minations : — 



