LABIATE 193
circulation of water. This basket, of course, holds a large charge, and
is manipulated by means of a pulley or swing-crane. The basket should
be about an inch from the bottom and sides of the still, and have copper
legs to rest upon. Sufficient, water is used with each charge to cover
the top of the basket. The finest portion of the oil condenses during
the first half-hour to hour of the distillation, and is usually reserved,
the remainder being collected separately. Eectification of lavender oil,
which renders it colourless, does not improve it. The somewhat
" herby " odour of the fresh oil soon passes off, and if the oil be kept in
cool dark places it improves by maturing for several years, and matured
oils are often sold according to the date of their preparation. After a
certain time it is said to deteriorate unless a little alcohol is added to it.
This oil, in common with several others distilled from plants of the
natural order Labiata, is one of those whose characters are altered
to a very remarkable degree by changes in the conditions of growth.
An expert now will usually distinguish a lavender oil distilled from
plants in and around Mitcham from one distilled in Cambridgeshire
or Hertfordshire, and although the ester value of all English oils is
fairly constant, foreign distilled oils invariably have much higher
ester values. This difference in ester value is brought about by entirely
different conditions from those which bring about a reduction in esters
where the plants yielding the oil " s'aspiquent". There it is a case of
cross-fertilisation of the two species of lavender.
The conditions of the lavender oil industry in France are well de-
scribed by Lamothe.
1
He gives a botanical description of the various Lavandula species^
and discusses the conditions which are most favourable for the existence
of lavender, the nature and treatment of the soil for laying out the planta-
tions, and the manner of doing so. According to him Lavandula species,
are divided as follows:—
- Lavandula latifolia Vill., Lavandula spica. var. /3 L. (grande
lavande, 1. male, 1. branchue, spic, aspic).
- Lavandula officinalis Chaix, Lavandula vera D. C., Lavandula,
spica, var. a L. (lavande veritable, 1. femelle).
Jordan classifies the latter into two sub-divisions, viz.:—-
Lavandula fragrans (lavande odorante, 1. moyenne).
Lavandula Delphinensis Jordan (petite lavande, 1. fine).
The first of these two varieties is widely distributed. It occurs at the
lower altitudes, whilst Lavandula Delphinensis is found exclusively in
the highest regions.
In addition to these, there occurs a cross between Lavandula lati-
folia and Lavandula fragrans, which Eeverchon calls Lavandula
Hybrida, and Chatenier Lavandula fragrans x latifolia (gross lavande,
- batarde, lavandin, spigoure).
The distillers, according to Lamothe, have the following designa-
tions for th - various lavender species :—
- Petite lavande. This yields the best oil, is more hardy, and less
fastidious than the next two which occur in lower regions.
- Lavande moyenne. Yields a less fine but still useful lavender oil.
- Gross lavande. Bastard, yields an inferior oil. Not to be con-
fused with the grande lavande (spike).
1
Lavand et Spic., 2nd edition, 1908.
VOL. I. 13
