PIPEKACE.E 113
- That the sample under review did not consist entirely of real
cubebs, and that fruits must have been present that produced an
oil, the physical qualities of which are very different from those of
genuine cubeb oil, even so much that there are fruits among them
which produce instead of the usual laevo-rotation a strong dextro-
rotation.
- That the reaction with concentrated sulphuric acid may be re-
garded an excellent expedient to recognise different kinds from irregular
cubebs, for all kinds colouring yellow with H 2 SO 4 also show important
irregularities of the physical constants of the oil.
OIL OF MATICO.
This oil is distilled from the leaves and spikes of Piper angustifolium
(Artanthe elongata Miq.), a plant indigenous to tropical America.
Probably other species are sometimes used for distillation, as the im-
ported leaves show considerable variation from time to time, and the.
following species have been recognised in commercial samples :—
Piper angustifolium.
„ camphor icum.
,, lineatum.
,, angustifolium v. Ossanuno.
,, acutifolium.
„ mollicomum.
,, asperifolium.
The yield of oil is very variable, from less than % per cent, to 6 per
cent. The oil is a liquid of somewhat penetrating odour, and has the
following characters :—
Specific gravity
Optical rotation
Refractive index
Acid value.
Ester
(after acetylation)
0-938 to 1-135
+ 6°
1-5300
4
8
50
It is usually soluble in 10 parts of 80 per cent, alcohol, but sometimes
25 parts are required. Very little is known of the chemistry of the oil.
There is present a small quantity of " matico camphor," a crystalline
odourless solid of specific gravity 1-080, melting at 94° and having a
specific rotation in chloroform solution - 28'7°. Its formula is C 15 H 26 O,
and it has been suggested that it is a derivative of ordinary camphor,
but there is no experimental evidence in favour of this, and it appears
to be a sesquiterpene alcohol. This body seems to be generally absent
from the oil distilled at the present time. Schimmel & Co. state that
they have found asarone C 12 H 16 O 3 in one sample of the oil, which had
the specific gravity 1*077, and was slightly laevo-rotatory.
An oil has recently been examined by Schimmel which contained
much asarone. A mixture of terpenes and cineol was also identified.
A sesquiterpene alcohol also appeared to be present in this oil, which
is possibly identical with the matico camphor which is now not always
present in normal distillates.
Fromm and v. Emsterl have isolated from matico oil a phenol
1
Bericht, 35 (1902), 4347.
VOL. I. 8
