Chemistry of Essential Oils

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82 THE CHBMISTEY OF ESSENTIAL OILS


and further states that " Sofia" is often found in poorly-drained
areas.
" Motia " grass is rarely, if ever, found growing gregariously over
large tracts of country ; it is generally found in single clumps a foot or
two apart which together form open grass land, while " Sofia " on the
other hand is much more gregarious in its habits and in some cases
covers considerable areas as a dense crop of grass.
Pearson^1 gives the following account of the distillation of the oil:—
The local practice, which is at present the only method by which
the oil is extracted from the stems, leaves, and flowers, is that of direct
firing of the still, steam distillation having t>nly been tried as an ex-
periment.
The portion of the plant from which the oil is obtained is the flower
and leaf, while only small quantities of the oil can be obtained from the
stem itself. The flowers and upper third of the stem are collected in
September and October, being tied into bundles or "pulas" of about
£th of a pound each. Donald^2 in describing the process of distillation
states that the inflorescences are cut twice, a second flowering occurring
after the first inflorescence has been cut. The grass is either distilled
in a partially green state or the flower heads and portion of stem are
carefully dried in the shade before distillation, during which period they
lose from about 20 to 40 per- cent, of their weight according to the
degree of dryness which they are allowed to attain before being treated.
The plant used by the local distillers varies little from district to
district in the Central Provirices and Bombay, being in every case of a
very primitive type. The still is in all cases erected within a few feet
of a stream or pond, because considerable quantities of water are
required for the distillation process itself and also for cooling the con-
denser. The still itself is of iron or copper and of cylindrical shape,
having a sufficiently large opening at the top to allow of the charge
being introduced; it is also often fitted with handles for transport pur-
poses. The size of such stills varies in different localities, varying from
12 to 14 gallons.
The still is either built in and covered with mud up to the neck, or
is simply supporced on stones over a fire-grate by which direct heating
is obtained. The opening at the top of the still is closed either with
an iron or wooden disc in which a 1^ in. to 2 in. hole is drilled in the
centre, the disc being luted to the still with flour paste or mud and
chaff, with the help of a. rag which forpas a wrapper over the joint. In
the hole in the disc is fitted a bamboo^' lS ins. to 2 ft. long, the joint of
which is also made good with flour paste. The upper end of the
bamboo is bevelled to an angle of 60° to take another section of bamboo
about 8 ft. long, the joint being either pegged or made good by wrapping
cloth round it, which is further secured by binding twine over the rag
and the whole covered with paste or mud. In order to form the
bamboo into a pipe the nodes are drilled through with the help of a hot
iron, this being done before the bamboo is fixed to the still. In some
cases the bamboo pipe is covered to within 6 ins. or 8 ins. of the lower
end with a strip of rag or it is bound the whole of its length with twine,
thus preventing the bamboo from splitting. The condenser is generally
made of copper, of bulbous shape with a long neck. Donald, however,


1
Loc. cit.
2
Indian Forester, xxxix. 3» 149.
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