Chemistry of Essential Oils

LAUKACE^E 153

'Specific gravity at 17°.

Optical rotation.

Refractive index at 16°

Acid value ....

Ester value

Ester value after acetylation

1-0396

-4° 54'

1-5180

i 2-8

0

35-5

It contains isoeugenol, safrol, and possibly cineol.

OIL OF CAPABBAPI.

This oil is yielded by the so-called " canelo ' tree of Colombia,

Jfectandra caparrapi. It varies in colour from pale yellow to dark

brownish-red, and is known in commerce under the names of " white "

and " black". It is a thick liquid of specific gravity about -915 to

*935, and rotary power - 3°. On exposure to prolonged cold, crystals

of an acid are deposited. The black oil probably owes its colour to

overheating. From a sample of the white oil, Tapia^1 has extracted

.an acid of the formula C 15 H 26 O 3 , which crystallises in -white needles,

.melts at 84 *5°, and has a rotary power [a\d = + 3°. In addition to this

body the oil contains a sesquiterpene alcohol, C 15 H 26 O, which the same

chemist terms caparrapiol. It has a specific gravity '9146, and a rotary

power [a]d = — 18*6°, and boils at 260° at atmospheric pressure. By

abstracting water by means of dehydrating agents, a sesquiterpene

C 16 H2 4 is formed, termed caparrapene. This is described as a colour-

less liquid, boiling at 240° to 250°, and of specific gravity -9019 and a

rotary power [a]d = - 2*2°. These compounds require further ex-

amination before they can be regarded as new compounds. The oil is

used for the same purposes as balsam of copaiba.

OIL OF SPICEWOOD.

The various parts of the plant Laurus benzoin (Benzoin odoriferum),
•commonly known as spice wood or wild allspice, yield aromatic volatile
oils. The plant is a North American shrub, inhabiting damp, shady
woods in localities extending from Canada to Florida. Schimmel &
•Co. state that all parts of the shrub possess pleasant aromatic odours,
which, however, are very different from one another. They obtained:
{L) From the bark, -43 per cent, of an oil smelling like wintergreen.
Its specific gravity was 923, and its constituents boiled between 170°
And 300°; (2) from the berries, 5 per cent, of an oil of a spicy aromatic
•odour, of specific gravity -855, with constituents boiling between 160°
and 270°; (3) from the twigs, -3 per cent, of an oil smelling like
camphor and calamus, specific gravity 925; (4) from the leaves,

• 3 per
  xsent. of an oil of pleasant lavender odour, specific gravity '888.
  The oil from the bark appears to consist largely of hydrocarbons,
  with about 10 per cent, of methyl salicylate. It also probably contains
  emnamic compounds.

OILS OF TETRANTHBBA.

Most parts of the plant Tetranthera polyantha v. citrata, a plant
found in Northern India, the Indian Archipelago and Java, yield an
essential oil. The fruit yields from 4 to 5 per cent, of an oil of the
following characters:—

i Bull. Soc. Chem. (1898), 638.