528 THE CHEMISTEY OF ESSENTIAL OILS
preparation of the oil. An oil obtained by extracting the flowers with
petroleum ether, and distilling the extract with steam (the water soluble
oil1 being recovered by ether) was examined by von Soden and found to
have the following characters:—
Specific gravity 0'961
Optical rotation..+ 31° 20'
Acid value 16
Ester , 85
The fresh roots of this plant yield from -01 to '04 per cent, of an un-
pleasantly-smelling oil recalling the odour of radishes. This oil contains
phenyl-ethyl-thiocarbimide, C 2 H 4 (C 6 H 5 )NSC, and is a liquid of specific
gravity 1-01 to 1-09 and optical rotation about + 1° to + 2°.TURNERACE/E.
OIL OF DAMIANA.The leaves of various species of the Damiana plant, principally
Turnera diffusa and Turnera aphrodisiaca, yield about O5 to 1 per cent,
of essential oil. The oil has the following characters:—
Specific gravity 0-943
Optical rotation - 23° 25'
Saponification value 41 '8
Another sample, distilled by Schimmel & Co., was found to have a
specific gravity 0'970 and to boil between 250° and 310°. By standing,
in the cold the oil deposits crystals which probably consist of paraffin
hydrocarbons.
CANELLACE^E.OIL OF CANELLA BARK.The bark of Canella alba yields from f to 1 per cent, of essential oil.
In the drug trade this bark is known frequently as " wild cinnamon,"
and is found in the south of Florida, the Bahamas, Cuba, Jamaica, Mar-
tinique, Barbadoes, etc. The whole tree is very aromatic, especially the
flowers, which perfume the neighbourhood for a considerable distance,
although they seldom open. The bark is brought to Europe in the form
of long quills, rather thicker than those of cinnamon. The taste of the
bark somewhat resembles a mixture of cloves and cinnamon, being hot,
bitter and aromatic. Meyer and Eeiche
x
investigated the oil, of which
they obtained '94 per cent, from the bark, so long ago as 1843, and stated
that they isolated four distinct bodies from it. The first was eugenol,
the second was described as being closely allied to the principal con-
stituent of oil of cajuput, and the other two were not closely investigated.
Fliickiger and Hanbury obtained 74 per cent, of oil from the bark, and
stated that it consisted of 2 parts of an oxygenated body mixed with
1 part of a hydrocarbon resembling a mixture of mint and cajuput oils.
Eugenol, however, remained as the only well-defined body yet ascer-
tained as a constituent of the oil, till 1890, when Schimmel & Co. showed
that the body referred to by Meyer and Eeiche as resembling the princi-
pal constituent of cajuput oil was actually identical with this, being the
now well-known cineol. Williams
2
has later examined the oil, and has
lAnnalen, 47 (1843), 234. * Pharm. Bund. (New York), 12 (1894), 183.