Chemistry of Essential Oils

454 THE CHEMISTBY OF ESSENTIAL OILS

The oil contains methyl-eugenol and a crystalline paraffin melting at 80*
to 81°.

OIL OF BOEONIA.

The herb Boronia polygalifolia, a plant found in most of the Australian
colonies, yields an essential oil which has been examined by J. C. Umney.
1

It is described as having a specific gravity 0*839 (is this a misprint?),
and an optical rotation + 10°. On fractional distillation the following
fractions were obtained :—

150° to 170° 3 1 per cent.

170° „ 180 °88 „

180° „ 190° 15 „

Above 190°.16 „

OIL OF EUE.

The genus Euta comprises about fifty species inhabiting the Medi-
terranean region and Eastern and Central Asia. The oil is distilled from
the herb Euta graveolens, yielding the French oil, whilst Algerian oil is
distilled from Euta montana, the summer rue, and Euta bracteosa, the
winter rue.
The various oils of rue have the following characters :—

FEBNCH OIL (EUTA GEAVEOLENS).

Specific gravity 0-830 to 0-845

Optical rotation.. .' - 0° 50' to + 3°

Refractive index 1-4300 to 1-4350

Solidifying-point5°,, 5° „ 11°

It is soluble in 3 volumes of 70 per cent, alcohol.

ALGERIAN OIL (EUTA MONTANA).

Specific gravity •.. 0-830 to 0-838
Optical rotation 0° to + 1°
Refractive index 1-4300 to 1-4325
Solidifying point + 7° „ + 10°
This oil, which is soluble in 2'5 to 3 volumes of 70 per cent, alcohol,
is known as " essence figeable " (congealing oil) in Algeria.

ALGERIAN OIL (EUTA BRACTEOSA).

Specific gravity 0-837 to 0-845

Optical rotation........ — 1° „ — 5°

Refractive index 1-4300

Solidifying-point below - 5°

This oil is known as " non-congealing oil" in Algeria. It is soluble,

often with turbidity, in 3 volumes of 70 per cent, alcohol.

SPANISH OIL.

Specific gravity 0-833 to 0-845

Optical rotation - 1° „ + 1°

Solidifying-point - 3° „ + 8

Imperial Inst. Jour., 2 (1896), 302.