BOSACE^E 405
quantity of ethyl alcohol exists in the oil. If this is so, which Poleck
denies, it is in all probability the result of fermentation taking place in
the leaves, by keeping them too long before distillation. Markovnikoff
and Eeformatsky^1 originally stated that the liquid portion of rose oil
consisted chiefly of an alcohol of the formula C 10 H 20 O, which they termed
roseol. Poleck and Eckart claimed that this alcohol had the formula
C 10 H 18 O, and was identical with geraniol. They, however, proposed the
name rhodinol (which was applied to an alcohol C 10 H 20 O from geranium
oil by Barbier and Bouveault) for it. Bertram and Gildemeister^2 then
showed that the alcohols from rose oil were in reality a mixture of two
bodies, of which they agreed that geraniol C 10 H 18 O was the chief con-
stituent. Tiemann and Schmidt explained these differences, proving
that the alcohols consisted of about 75 per cent, of geraniol C 10 H 18 O and
25 per cent, of an alcohol C 10 H 20 O, which was identical with that obtained
by reducing citronellic aldehyde. Hence they naturally insisted on the
name citronellol, whilst Eckart claimed to have isolated an alcohol of the
formula C 10 H 20 O which he named rhodinol. For many years rhodinol
was regarded as an impure citronellol, but the two bodies are now known
to be separate individuals. Much confusion has unnecessarily been
caused by various chemists giving names to alcohols they had isolated from
different oils in an impure state, and refusing to alter these names after
it had been conclusively proved that they were, when pure, identical with
already known bodies. Lemonol, reuniol, and roseol are all either
geraniol or citronellol, or mixtures of them. The relationships of
rhodinol and citronellol are discussed in Volume II. Traces of esters of
these two alcohols, and of free acids resulting from their decomposition
also occur. The stearoptene was regarded by Markovnikoff as consist-
ing of a single paraffin hydrocarbon of the formula C 16 H 34 , melting at 37°,
but Schimmel & Co. have separated two hydrocarbons melting at 22° and
41° respectively from the stearoptene. This has been confirmed by
Dupont and Guerlain. These chemists suggest that the ester, which
appears to be found in larger quantity in French oils than in any other,
is an important odoriferous constituent, and is destroyed by repeated
distillation with water. They separated the liquid portion of the oil and
found it had an optical rotation of - 10° 30', which decreased to - 7° 55'
after hydrolysis. Charabot and Chiris invariably find rose water acid,
which tends to confirm this hypothesis.
Phenyl ethyl alcohol has recently been shown to be a normal con-
stituent of otto of rose, but it appears to be mostly, if not entirely lost or
destroyed by the Bulgarian method of distillation. Nerol is also present
in small amount as well as, probably, farnesol, a sesquiterpene alcohol
C 16 H 26 O, present in oil of cassie flowers. Eugenol, linalol, and nonylic
aldehyde are also present in traces.OIL OF ALMONDS.Oil of bitter almonds is obtained from the kernels (seeds) of the
ordinary bitter almond, Primus Amygdalus (Amygdalus communis), a
tree which is cultivated in Europe, Asia, Northern Africa, and Cali-
fornia. The kernels of the peach and apricot yield essential oils which
are practically identical with that from the almond, and many samples
of " almond oil " of commerce are no doubt derived from peach and
r. Praki. Chem., II, 48 (1893), 293. *Ibid., II, 49 (1894), 185.