can be made at slight cost from the flowers, as the raw material is obtainable without much trouble; it forms a yellow, strong-scented oil. In perfumery, however, use is generally made only of the pomade made from the fresh flowers or the alcoholic extract prepared from it. Or else the odor is imitated by means of terpineol, which is now on the market under the name of lilacin.
Oil of Geranium.
It is necessary to distinguish clearly between oil of true geranium distilled in Southern France and Algiers from species of Pelargonium; and Turkish oil of geranium, also known as Palmarosa oil, oil of geranium grass, oil of Rusa grass, etc., which is distilled in India from ginger grass. (See above, p. 33.)
The first-mentioned oil has a much finer aroma than the second. The two oils are frequently confounded, even in prominent works of reference.
When oil of geranium or of rose geranium is directed to be used, the French (or Algerian, or Spanish) oil should be employed. These cost more than twice as much as the so-called Turkish or palmarosa oil.
Oil of Heliotrope.
This oil which does not yet occur in commerce (we find merely the pomade and the alcoholic extract of the latter) has been made by the author experimentally; the most suitable method was found to be extraction with petroleum ether. As the plant, Heliotropium peruvianum, the source of this delightful odor, is frequently cultivated in our gardens, the preparation of the oil by this method is to be recommended, being less expensive and more rapid than by the use of fat, while the product obtained with petroleum ether is as fine as that extracted by alcohol from the pomade.
Oil of Elder (Oleum Sambuci).
The remark made under the head of oil of lilac applies equally to this oil. For the benefit of those who wish to make this oil in its pure form we may add that it is absolutely necessary to select only the freshest flowers, otherwise the odor will be very much impaired.