Chemistry of Essential Oils

380 THE CHEMISTKY OF ESSENTIAL OILS

OIL OF MELALEUCA MAIDENI.

This tree is found in New South Wales and Queensland. The oil
has the following characters:—
Specific gravity 0-9199 to 0-9234
Optical rotation - 0-7° „ - 4-2°
Refractive index ..... 1-4744 to 1-4800 at 22°
Eucalyptol. 26 to 39 per cent.
The oil contains, in addition to eucalyptol, Z-pinene, Z-limonene, an
alcohol, a sesquiterpene alcohol, a sesquiterpene (?), and benzaldehyde (?).

OIL OF MELALEUCA SMITHII.

This is the common broad-leaved Melaleuca of certain districts of

New South Wales. Three samples examined by Baker and Smith had

the following characters:—

Locality.

Hose Bay, Sydney

Terrigal, N.S.W.

21/12/1911

Gosford, N.S.W.

20/9/1899

Yield

per

Cent.

0-607

0-923

0-495

Specific

Gravity

at 15°.

0-8815

0-9003

0*8976

Eucalyptol

per Cent.

About

less

than 2

about

5

Rotation

+ 11-8°

+ 6-7°

+ t> o

Refractive

Index

at 22.

1-4812

1-4824

1-4806

Saponifica-

tion

Number.

3-1

3-3

6-5

In addition to eucalyptol, the oil contains benzaldehyde (?) Z-pinene
7-limonene, dipentene, and a sesquiterpene alcohol, which has been
termed melaleucol. It is suggested that this alcohol may be related to
the alcohol nerolidol, in the same way as geraniol is to linalol. The
identity of this body, however, is hardly established by experimental
evidence.

OIL OF MELALEUCA THYMIFOLIA.

This oil has the following characters :—

Specific gravity0-9134

Optical rotation +2-1°

Refractive index1-4665a

Yield

It contains about 53 per cent, of eucalyptol.

OIL OF MELALEUCA LINARIFOLIA.

This oil has the following characters :—

Specific gravity0*9129

Optical rotation + 2 -5°

Refractive index 1-4741at

Yield 1-214 per cent.

It contains much terpenes and but little eucalyptol.

OIL OF MELALEUCA UNCINATA.

This tree yields 1-246 per cent, of essential oil which has the fol-

lowing characters:—

0-9134

+ 2-1°

1-4665 at 23°

2-28 per cent.

0*9129

+ 2-5°

1-4741 at 22°