164 THE CHEMISTEY OF ESSENTIAL OILS
were found to belong to Cinnamomum camphora trees. It is stated
that even in Formosa varieties exist which yield oil from which no
camphor separates, and it is proposed that fresh trials should be made
in Mauritius, and that fresh seed should be procured from selected trees-
in Ceylon or the Federated Malay States which are known to yield
camphor.
The essential oil of Hernandia peltata, a Madagascar plant known
as a false camphor, has been examined by Schimmel & Co.^1 From the
stem wood from 1*03 to 2*06 per cent, of oil was obtained, having the
following characters:—
Specific gravity at 15° 0'958 to 0-963
Optical rotation + 83° 45' „ + 104° 12'
Eefractive index 0-49695 „ 1-50111
It contains from 75 to 80 per cent, of aldehydes (mostly dihydro-
cumic aldehyde), with traces of free acids and a small amount of esters.
In addition to dihydrocumic aldehyde, the oil contains a small amount
of the aldehyde myrtenal, which has a specific gravity 0*986 at 20°,
specific rotation + 13*6°, and refractive index 1-50618. The root wood
yielded 0'5 per cent, of oil having a specific gravity of 0P9667, optical
rotation + 126° 15', refractive index 1-50383 and aldehyde content
92'5 per cent. The whole fruit gave 0*5 per cent, of oil of specific gra-
vity 0-9528, optical rotation + 50° 10', refractive index 1*49554, and
aldehyde-content 49 per cent. The almond-like seeds gave T38 per
cent, of oil, having a specific gravity 1*0044, optical rotation + 87°, re-
fractive index 1-50614, acid value 7
*
3, and aster value 110
*- The fruit
oil does not appear to contain any dihydrocumic aldehyde. It is pos-
sible, however, that the aldehyde present is perillic aldehyde, and not
dihydrocumic aldehyde.
The leaves of the Japan camphor tree also yield an essential oiL
According to Hooper the yield is about 1 per cent., the oil having a
specific gravity about 0
- 930 and optical rotation + 4° 32'. It contained
10 to 15 per cent, of camphor. Another specimen contained 75 per
cent., and had a specific gravity -9314 and optical rotation + 27°. There
seems not to be much difference between this and the ordinary camphor
oil. The roots yield an oil of quite similar character. A sample dis-
tilled by Schimmel & Co. had a specific gravity "975, and consisted
chiefly of camphor—the liquid portion resembling commercial camphor
011 very closely.
OILS OF SHO-GYU AND YU-JU.There are found in Formosa two trees which closely resemble the
ordinary camphor tree, which are known as Sho-Gyu and Yu-Ju, and
whose actual botanical differences from the true camphor tree are not
yet determined. Both these trees yield essential oils which have been
investigated by K. Nagai,
2
who gives the following details of them :—
" ' Sho-Gyu Oil' is the name given to an essential oil with an aro-
matic odour, disti'led from a perennial tree popularly called by the
natives ' Chi
u
n-Gru,'
- growing chiefly in the highland forest regions of
Formosa. On account of its not producing camphor through the reg-
1
2 Schimniel's Bericht, April, 1915, 54.
3 Publication of the Monopoly Bureau, Formosa. Taihoku, 1914.
Chin
or Shd = camphor tree; GH or Gyu = ox.