_Ceylon cinnamon oil_ (_oleum cinnamoni ceylonici_).--Formerly this oil was exclusively distilled from chips and waste of the genuine cinnamon bark of the _Cinnamonum ceylonicum, Nees_, and came into commerce from Ceylon. However, the fabrication of the oil from cinnamon waste or chips is now extensively carried on in Germany, and this oil, being prepared with the assistance of more perfect apparatus, has almost entirely supplanted that exported from Ceylon. When fresh, the Ceylon oil is colorless, but when stored for some time it becomes first golden yellow and later on brownish. It is thickly-fluid and heavier than water, its specific gravity being 1.060 to 1.090. It has an agreeable, aromatic odor and a biting but pure, sweet taste. Its principal constituent is cinnamaldehyde (C_{9}H_{8}O), and it contains, besides, 4 to 8 per cent. of eugenol. The presence of the latter in cinnamon oil may be established by shaking with 15 per cent. soda-solution, whereby the eugenol is dissolved, and decomposing the aqueous solution with hydrochloric acid. The eugenol separated thereby gives in alcoholic solution, when compounded with a trace of ferric chloride, a beautiful blue color. _Cassia oil_ (_oleum cassiæ_).--In China and Cochin China this oil is obtained by distillation from the bark, unripe fruits, buds, and other waste of the _Cinnamonum cassia_ or _Cinnamonum aromaticum, Nees_, a tree indigenous to those countries. It has a pale yellow color, which in time becomes brown. It is thickly-fluid, of specific gravity 1.05 to 1.07, and possesses a sweet taste with an acrid after-taste. Like cinnamon oil, it consists chiefly of cinnamaldehyde, but contains no eugenol, and hence can be readily distinguished from Ceylon oil by the above-mentioned reaction. One part of pure cassia oil dissolves in two parts of 80 per cent. alcohol. _Cinnamon root oil and oil of cinnamon leaves._--Neither of these oils contains cinnamaldehyde, but abundant quantities of eugenol, the root oil as much as 50 to 70 per cent. The root oil is quite limpid and has an agreeable odor of cinnamon and cloves. The leaf oil is thickly-fluid, of the consistency of castor oil. The Ceylon oil is frequently adulterated with cassia oil. Such adulteration is very difficult to detect, and can only be recognized by experts by the odor and taste. The quality of cassia oil is recognized by the taste and odor, especially on heating, and the high specific gravity, in consequence of which the oil sinks in water. According to Hager, cassia oil is frequently adulterated with oil of cloves. This is, however, scarcely probable, the price of oil of cloves being, on an average, higher than that of cassia oil. The latter, however, is frequently adulterated with cheaper thickly-fluid volatile oils, especially with cedar oil. In this case the oil does not dissolve in the above-mentioned proportion in alcohol.