144 



luidefinecl constitution, are also obtained from tlie root of Coclileai-ia 

 Armoi'acia and of Sisymbrium Alliaria; from the herb of Cochleai-ia 

 officinalis; from the herb and seeds of Iberis amara; mixtures of 

 the oils of mustard and of garlic are obtained from the herb and 

 seeds of Thlaspi arvense ; from the seeds of Nastui'tium officinale ; 

 Thlaspi Bursa pastoris; peculiar oils, containing sulphur, are fur- 

 nished by Lepidium sativum, Raphanus sativus, &c. — It is colour- 

 less or yellowish ; of an intensely penetrating smell and taste of 

 mustard; of I'Ol density; dissolves slightly in water; readily in 

 alcohol and in ether; attacks potassium metal violently, forming 

 another oil and sulphocyanide of potassium; decomposes, on heat- 

 ing with monosulphide of potassium, into the sulphocyanide and 

 oil of garlic; absorbs much ammonia and is converted into a white 

 crystalline mass of thiosinaminriiCs Hs N2 S2. 



Oil of Brassica oIeriicea=RAPE-oiL, 



Oil of Buplitlialiiiuni. See Buphthalmum-Stearopten. 



Oil of Bursera «•Ullllllifera = C20 Hie- Obtained by distilling 

 the Gomart-resin (an exudation of the stem) with water. Is 

 similar to oil of turpentine. 



Oil of Caiiielina Ssltiva, Obtained by pressing the seeds. 

 Thicker than hempseed-oil, inodorous and tasteless; of 0'925 

 density; freezes at — 19°; yields soft soaps. Dries at the air. 



Oil of Cauella alba (white cinnamon). Obtained by distilling 

 the bark with water. It is a mixture of caryophyllic (eugenic) 

 acid, an oil similar to that of cajeput and an oxygenised oil. 



Oil of CaimabiS sativa (hemp). The fixed oil is obtained by 

 pressing the seeds. — At first greenish or brownish-yellow; tui-ns 

 yellow at the air; has a mild taste; specific gravity=z0'927 ; 

 dissolves in thirty parts cold and in any proportion of boiling 

 absolute alcohol; saponifies with difficulty, the soaps not being 

 so soft as those of linseed oil ; belongs to the non-drying oils. 



The volatile oil is obtained by distilling the herb with watei-. 

 Pale-yellow; smells like the green herb; tastes aromatic, not 

 burning, but penetrating; is lighter than water. [According to 

 Personne, it consists of two hydrocarbons — one liquid (Cannaben 

 =:Cis Il2o)> the other solid, forming platy crystals (Hydride of 

 Cannaben zzCis H22).] 



Oil of Carapa fiJllianeilsis. Obtained by distilling the seeds 

 with Avater. — Colourless, unctuous; of very bitter taste; becomes 

 solid at 4°. 



Oil of CarulU Carvi (caraway). Obtained by distilling the 

 fruit with water. — Colourless or pale-yellow; thin; of a strong 

 taste and smell of the fruit; of 09 1-97 density; begins to boil at 

 175°, Carven passing over, while Carvol distils up to 232°. 



