161 



proportion. The Oleates are soft, frequently oily, or readily 

 fusible to an oil ; tliey dissolve more readily in alcohol, and 

 especially in ether, than in water. The Oleic acid forms a solid 

 mass with hyponitric acid. 



Olein (Tri-olein) = CiosHio4 0i2=C6H5 Os + 3 C36 H33 O3. 

 Forms the main ingredient of the non-drying oils, and is in less 

 quantity contained also in solid fats. Expose any fixed oil of 

 this kind to a temperature of — 5°, press, treat the liquid portion 

 again to a temj^erature of — 10°, and press again, removing the solid 

 part. — Neutral oil, inodorous, of mild taste, and of 0"914 density ; 

 remains liquid below — 10°; volatilizes in a vacuum, undecomposed, 

 and partly at ordinary temperature ; dissolves very little in 

 alcohol, copiously in ether, is more i-eadily saponified than the 

 drying oils and the solid fats; becomes rancid at the aii-, and of a 

 thicker consistence in thin layers, but not dry. Is solidified by 

 hyponitric acid. 



OlibtllllUU. Gum-resinous exudation of Boswellia Carterii. — 

 Yellowish or brownish grains, on the surface of a mealy appear- 

 ance, of a faint aromatic smell, which becomes stronger on 

 warming, of an aromatic, somewhat acrid, bitter taste ; contains 

 56% resin, 31% gum, 6% bassorin, and 5% volatile oil. The resin 

 is reddish yellow, brittle, tasteless, softens at 100°, but fuses only 

 at a much higher temperature, and consists of C40 H32 Oc. 



Olivauiariu. Bitter ingredient of all pai'ts of Olea Europsea, 

 occurring especially in the leaves, and still more in the unma- 

 tured fruits, but as yet only known as extract. 



Olive Oil. Obtained by pressing the succulent part of the 

 fruit of Olea Europaja. — Greenish yellow, of mild and pleasant 

 taste, and of 0'916 density ; congeals partly at 10° to granules, at 

 0° completely ; dissolves very little in wood spirit and alcohol. 

 Consists in the main of 30% palmitin, and of 70% olein. 



Olivil = C2S His Oio + 2 HO. In the gum of the olive-tree, 

 associated mth resin and with a little benzoic acid. Treat the gum 

 with ether, which dissolves the resin ; boil the residue with alcohoj. 

 of 36° B. ; filter hot and let cool. A crystalline pulp is obtained, 

 which has to be washed with cold alcohol, and recrystallised in 

 boiling alcohol. — Forms colourless crystals, inodorous, of a bitter- 

 sweet and slightly aromatic taste, neutral, fuses at 1 20°, losing its 

 water ; decomposes in a highei- temperature ; dissolves little in 

 cold, in 32 parts boiling water, readily in alcohol, wood spirit, and 

 concentrated acetic acid, little in ether and oils ; turns blood-red 

 with concentrated sulphuric acid, and becomes later carbonized; 

 is not altered by diluted sulphui-ic or hydrochloric acids. 



OllOCerin=::C24 H20 O2. In the root of Ononis spinosa. 

 Evaporate the alcoholic tincture of the I'oot to the consistence of 



M 



