OILS AND OIL SEEDS. 



speaking, is an essential oil dissolved in spirit, and equivalent to the 

 French Esprit or Extrait. The first alone of those produced in India have 

 been catalogued in detail ; the second, whether Indian or foreign, have 

 been named incidentally only under the Remarks. Strictly all mention 

 of them should have been omitted here, as their more proper place is, 

 perhaps, the " Miscellaneous Class/' But I found I could not pass the 

 different natural orders without recognizing them, and only the most im- 

 portant of such as are Indian will re-appear under the " Miscellaneous 

 Class," and these not so much for their commercial importance as for the 

 historical interest attached to their sources. 



The natural Vegetable Fats, or Fixed oils, are obtained generally by 

 expression, sometimes aided by heat, and in a few cases by boiling the 

 tissue containing them in water. They generally occur in the seed. 

 Their proximate principles as a rule are margarine, stearine, and oleine, 

 of which two are always present ; and their consistence depends on the 

 predominating principle, stearine giving their consistence to hard oils, 

 margarine to soft, and oleine to liquid. 



Volatile oils, or essences, are prepared by distilling plants, or parts of 

 plants, with water. They are also obtained from the resins ; and oleo-resins, 

 called balsams. Some pre-exist in the plants, others as oil of bitter almonds, 

 are only formed during the operation of distillation. They are arranged 

 in three classes : the non-oxegenated, containing carbon and hydrogen, as 

 oil of turpentine ; the oxegenated, containing oxygen, in addition to carbon 

 and oxygen, as essence of cinnamon ; and the sulphuretted, containing also 

 sulphur, as the volatile oil of garlic and asafoetida. Many deposit a 

 crystalline principle, called stearoptine, of which camphor is an example, 

 and which is also obtained from Anise and Ajwan. In India the volatile oils 

 are seldom obtained isolated, the perfumers being content to communicate 

 their odours to fixed oils, or fats, by enfleurage. 



In the above list, Essences, which are mere curiosities, have been 

 omitted entirely as Elder-flower, Honey-suckle or Woodbine, Mignionette, 

 Sweet-pea, Pine-apple, Magnolia, Jonquil, Lilac, Tuberose, Geranium, 

 Violet, and Meadow Sweet. Many Essences, it may here be mentioned, 

 bearing the names of plants, are not derived from them, but are prepared 

 artificially, as Volkameria, Hovenia, Eglantine, or Sweet Briar, and 

 Heliotrope. Violet and Geranium are sometimes fictitious also. 



The Essences being used as perfumes, all perfumes may be looked for 

 here. Several of those not included under this class were mentioned 

 under " Gums and Resins," as the Storax and Balsam (. e. Balsam of Peru 

 and Balsam of Tolu) of perfumers. The remainder, as Rhodium, Sandal- 

 wood, Orris (the chief ingredient in the bouquet known as Jockey Club 

 and Rowland's " oriental herb" " Odonto"), Cascarilla, and Aloes-wood ; 

 Cedar, will be detailed under the " Miscellaneous Class." 



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