Chemistry of Essential Oils

LAUBACE^E 157

oil exudes from it which is collected and is known as oil of camphor.

The majority of the oil is, however, produced by distilling the chips

with water in crude stills. The crude product amounts to about 3 per

Distilled

in

Ceylon.

India

German )

E. Africa J

Jamaica

West Indies.

Italy

America

Willis & Bamber.

Hooper

Lommel

Duncan

Watts & Tempany

Giglioli

Hood & True

Yield

per Cent.

rO-06 to 0-1

\ 0-22

0-61

0-05

2-37

2*52

1-39

0-5

0-5

0-7

1-2 to 1-5

2-4 „ 3-0

0-02 „ 0-25

2

0-7

2-77

Material. the Distillate.Properties of

Leaves and small

Stems

Branches and thin

Twigs

Young shoots

Wood

Twigs

Green Leaves

Dried „

Dead „

Wood

Leaves and Twigs

Green Leaves

Dry „

Twigs

Shed Leaves

Trees from Shady

places

Trees from sterile,

shady places

Contained

from 10 to

75 per Cent.

Camphor

Camphor and

Oil

Crude

Camphor

Camphor and

Oil

Camphor

Camphor and

Oil

cent, of the wood used. The oil is drained from the crystalline cam-
phor, of which it retains a considerable amount in solution. This is
transferred to a still, and about two-thirds is distilled off, leaving the
bulk of the camphor in the residue, which is cooled and pressed to
separate more camphor. This process is repeated so long as it pays,
and the residue forms the camphor oil of commerce. From a scientific
point of view, one must regard the whole of the products of distillation
of the wood as camphor oil. This, however, contains so much solid
camphor, or stearoptene, that it is commercially regarded as a separate
product, and the liquid portion of the oil is thus known as oil of cam-
phor. Hence the great variability in its properties and composition.
The crude camphor arrives in England in various states of purity,
and is refined by sublimation, generally with quicklime and charcoal..
Formerly camphor oil was regarded as having no value. To-day, how-
ever, it is used to an enormous extent in the preparation of safrol,
which is used as a cheap perfume, for the manufacture of artificial oil
of sassafras, and for the synthesis of heliotropin.
Camphor oil appears on the market in various forms, and as it is a
by-product, varying in characters according to the substances which.