and essential oil, erroneously called "white cinnamon," is obtained by the aqueous distillation of the bark of Canella elba (see Drugs—Canella, p. 796); it is a mixture of caryophyllic (eugenic) acid, an oil resembling cajuput, and an oxygenized oil. It is not a commercial article.
Essential oils of considerable, importance are derived from the true cinnamon of Ceylon, Cinnamo mum zeylanicum (see Spices—Cinnamon). Foremost is that yielded by the bark, to the extent of per cent., which is extensively distilled (aqueous) in Ceylon, and rarely in England. It is a golden-yellow liquid, with powerful cinnamon odour, sweet and aromatic but burning flavour, and sp. gr. 1.035. It is largely used in perfumery. Ceylon ships some 15,000-40,000 oz. annually of this oil, ohielly to England. A century ago, the average yearly sales by the Dutch E. India Co. were but 176 oz. The leaves afford a brown, viscid, essential oil, of clove-like odour, sp. gr. sometimes exported from Ceylon ; and a third oil is supplied by the root,—a yellow liquid, lighter than water, with an odour of camphor and cinnamon, and a strong camphoraceous flavour.
Various species of Cinnamomum occurring in Tropical Asia afford the so-called " cassia-bark" (see Spices—Cassia). From this bark, is distilled, notably in China, an essential oil agreeing chemically with that of Ceylon cinnamon-bark, but of less agreeable odour, and sp. gr. 1.066. The yield by distillation is about lb. of oil from 1 cwt. of bark. The oil is an export of no small importance from some Chinese ports. Pakhoi shipped 66,650 lb. in 1877, and 200 piculs (of 1331 lb.) in 1879 ; Macao exported about 480 piculs in 1879. A large proportion comes to Great Britain, but Hamburg seems to be the most important destination. The oil is used for perfuming soaps.
of the "grass-oils," called "citronella," is obtained from Andropogon nardus [A. Martini], attaining a height of 6 ft. and more. It grows wild abundantly in Singapore, and a large area is under cultivation with it, both in Ceylon and Singapore. In Ceylon, it is cut for distillation at any time of year, but mostly in December-January. The leaves are distilled with water, and yield over 3 oz. of essential oil from 1 cwt. The pure oil is thin, colourless, with strong aromatic odour, and acrid citron-like flavour. It is a growing article of trade. The ship
ments from Ceylon were 622,000 oz., value 8230/., in 1864; in 1874, they were 1,163,074 oz. to the United Kingdom, 5713 oz. to British India, and 426,470 oz. to the United States ; total, 1,595,257 oz., in addition to 842 doz. and 33 packages to the United States. Its almost only application out of India is for scenting soap, the consumption being very extensive. The best kind bears the name of John Fisher (of Singapore, and 43 Mincing Lane). Fisher's 950-acre estate on the island of Singapore now produces about 1 million oz. yearly of this oil.
Oils from other species of Andropogon are described under Ginger-grass and Lemon-grass (pp. 1422, 1423).
Clove-oil.--An essential oil is obtained from the flower-buds and flower-stalks of cloves (see Spices—Cloves) by aqueous distillation. This distillation is largely carried on in England. The proportion of oil present may amount to 16-20 per cent., but to extract the whole, the distillation must be long continued, the water being returned to the same material. The oil is a colourless or yellowish liquid, with powerful odour and flavour of cloves, and varying in sp. gr. from 1.046 to It combines well with grease, soap, and spirit, and is one of the most extensively-used oils in perfumery. In Germany, clove-oil is often adulterated with carbolic-acid (phenol).
Clove-bark-oil.—The bark of Dicypellium caryophyllatum, a native of Brazil, affords by aqueous distillation an essential oil bearing great resemblance in all its properties to clove-oil.
Coffee-oil—Coffee-berries (see Coffee, pp. 691-722) contain a proportion of essential oil vary ing from 8 to 13 per cent. This is partially given off during the roasting process (see Beverages— Coffee, pp. 422-3), and at least half is wasted, the remainder producing the characteristic odour and flavour of the berries. By the existing method of roasting coffee, it is scarcely possible collect the volatilized oil, on account of its being so largely emitted during the shovelling of the beans in the open air when withdrawn from the roasting-drums. It is suggested that the drums should be in connection with an exhauster, so as to condense the oil in a receiver, and at the same time cool the beans sufficiently to prevent ignition. It is thought that the oil might be profitably used in making liqueurs.