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Leaves

— The following particulars in regard to the oil from this species are taken from Messrs. Baker and Smith's Research on the Eucalypts:—

   
Specific gravity at 15°C.  Specific rotation.  Saponification number.  Solubility in Alcohol.  Constituents found. 
0.9042 to 0.9321  +5.36° to +6.19°  7.21 to 21.96  1 1/2 vols. 70% to 6 vols. 70%.  Eucalyptol, pinene, phellandrene. 

The same authorsnote give the specific gravity of the crude oil as 0.905 and of the rectified oil, 0.902, the latter containing 58 per cent. of cineol (eucalyptol). They further state that the cineol content of the oil increases towards the winter, but they are of opinion that the higher percentage of cineol has no influence on the specific gravity.

Mr. E. J. Parry, B.Sc.,note gives somewhat different figures, viz.:—Specific gravity, 0.917; specific (optical) rotation, 0°37' and 52 per cent. of eucalyptol. Mr. Parry challenges the statement that the percentage of eucalyptol is practically independent of the specific gravity.

Messrs. Baker and Smith's rejoinder follows.note Mr. Parry at the same place note maintains the correctness of his observations, and there the matter rests for the present.

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