Chemistry of Essential Oils

504 THE CHEMISTEY OF ESSENTIAL OILS

larger particles of earth in a winnowing machine. The average yield of
seed is from 40 to 50 poods per dessiatine.
" The seed is of a greyish-green colour. Quite green seed is obtained
when the anise is harvested in an unripe state. It is extremely rare to
find anise of a quite uniform colour, some proportion of dark seed, more
or less, being generally present; this seed is usually that of the central
flowering-head which has ripened first, or of plants which have been
affected by the conditions of the weather. For even after the fruit has
set the anise plant is still greatly affected by the weather, being liable to
damage by rain or dew immediately followed by hot sun; where such
damage occurs the colour of the seed changes quickly from green to
yellow, brown, and deep blackish-brown.
" The seed is rarely cleaned effectively, owing to the great cost of clean-
ing (1*50 roubles per pood on an average). It is invariably admixed with
some immature seed (from the branch-umbels), chaff, particles of earth
(either the remains of earth adhering to the roots or collected on the clay
threshing floor) and the seed of various weeds, especially of coriander, a
plant which cannot be entirely eradicated from an anise field.
" Apart from these»natural admixtures (about 7 to 8 per cent, of foreign
substances), deliberate adulteration of anise is much practised by the
farmers. Not only do they add earth-particles of a size and colour corre-
sponding with those of anise, but also the seeds of different weeds which
are indistinguishable from anise at the first sight. Eecently the seed of
another umbelliferous field-plant has also been added, and this form of
sophistication is no doubt the .most dangerous, because this seed closely
resembles anise in its colour, and is extremely difficult to recognise even
by the most careful examination. This seed has a faintly bitter taste.
" In order to form an estimate of the coming crop it is necessary to
make two journeys through the anise country, the first at the beginning
of July, with the object of collecting particulars of the area sown from the
' volostines' (district administrators). These figures are generally readily
supplied by the officials for a small consideration. When all the figures
have been collected it is most important to form a correct estimate of the
fields in the various districts, and to do this, practical experience is neces-
sary. The particulars relating to the sowing cannot be gathered before
July, as they are not prepared until then, and the second journey must be
made when the harvesting is in full swing, because then the anise crop is
no longer subject to any further dangers. Moreover, the evaluation of
the seed while the crop is standing is a safe guide, in particular because
it is also possible then—that is to say at gathering time—to find out the
number of bundles to a given superficial area, and to see the size, weight,
and colour of the seed. When the latter has been good, and the prices
also have been satisfactory, the farmers usually increase their sowings in
the following season, and vice versa."
The two oils are practically identical, except that the true aniseed oil
has a rather more delicate odour and flavour than the star aniseed oil.
The oils have the following characters:—

Specific gravity at 20°

Optical rotation.

Refractive index

Congealing-point

Melting-point

Star Aniseed Oil.

0-980 to 0-990

0° to - 2° (rarely slightly dextro-rotatory)

1-5530 to 1-5565

15° „ 17°

16-5° „ 19°