Chemistry of Essential Oils

374 THE CHEMISTRY OF ESSENTIAL OILS

It contains pinene, eucalyptol (about 5 per cent.), aromadendral,

and a sesquiterpene.

An Indian oil, examined by Ghose,^1 had the following characters :—

Specific gravity 0-903

Optical rotation - 22-3°

Refractive index 1-4905

OIL OF EUCALYPTUS TESSELLARIS.

This oil has the following values :—

Specific gravity 0-896

Optical rotation ........ + 8-8°

Refractive index.1-4881 at 16°

Yield 0-16 per cent.

It contains pinene, cymene, eucalyptol, and aromadendrene.

OIL OF EUCALYPTUS TRACHYPHLOIA.

This oil has the following characters :—

Specific gravity, 0'893

Optical rotation + 9-8°

Refractive index 1-4901 at 16°

Yield 0-2 per cent.

It contains pinene, aromadendrene, aromadendral, and eucalyptol.

OIL OF EUCALYPTUS UMBRA.

This oil has the following characters :—

Specific gravity 0-8963

Optical rotation + 37-4°

Yield 0-16 per cent.

It contains d-pinene, eucalyptol, and some esters.

OIL OF EUCALYPTUS UNIALATA.

This tree is a Tasmanian eucalypt. Its oil contains about 60 per

cent, of eucalyptol, d-pinene, and a sesquiterpene; and has the follow-

ing characters :—

Specific gravity 0-918

Optical rotation + 3-1°

Refractive index 1-4690 at 18°

Yield 0-9 per cent.

OIL OF EUCALYPTUS URNIGERA.
This oil has the following characters :—
Specific gravity 0-9088
Optical rotation.+ 10-6°
Refractive index 1-4638 at 23°
Yield 1-13 per cent.
It contains about 60 per cent, of eucalyptol, d-pinene, and geranyl
acetate.

(^1) P. and E.O.R. (1919), 145.