— 74 — 
Oil of Orange -blossoms [AurantU florum essentia). Yellowish, 
becoming brown on exposure to the light, slightly fluorescent. 
dj^o =0,870 to 0,880; soluble in 1,5 to 2 vol. 80 per cent, alcohol to 
a clear liquid with a blue- violet fluorescence; cloudiness on further 
addition of solvent. 
The determination of the saponification number: 20 to 55, would still be 
desirable. 
Oil of Peppermint {Menthae essentia). Colourless of yellowish; 
dj^go = 0,900 to 0,920; soluble in an equal vol. alcohol; the solution 
of 0,1 gram oil in i cc. glacial acetic acid should acquire after some 
time a blue to blue -violet colour when i drop nitric acid is added. 
According to the above, both English and American oils are allowed. 
Oil of Rose {Rosae essentia). Crystalline, light yellow mass. 
Soluble in an equal vol. chloroform, from which it is partly again 
precipitated by a large excess of alcohol; when the molten oil is cooled 
to 18° to 20° transparent crystals in the form of needles or leaflets 
separate out. 
Oil of Rosemary {Rosmarini essentia). Colourless or yellowish: 
d^^o =0,900 to 0,920; soluble in one-half part by weight of alcohol. 
Oil of Rue (Rutae essentia). Colourless or yellowish: d-^50 =0,833 
to 0,840; congealing point 8° to 10°; soluble in 2 to 3 parts 70 per 
cent, alcohol. 
Methyl ester of Salicylic Acid {^Salicylate de methyle). Colourless; 
dj^go = 1,1819 1); boiling point 220°; saponification number at least 
360; sparingly soluble in water, soluble in alcohol and ether; identity- 
reaction with ferric chloride. 
^) The specific gravity of pure methyl salicylate lies a little higher, i. e. between 
1,185 ^"^^ (15°). 
Oil of Sandalwood, East Indian [Santali essentia). Light 
yellowish; d-L50 = 0,975 to 0,985; boiling point 275° to 295°^); 
soluble in 5 parts 70 per cent, alcohol; santalol-content at least 90 per 
cent; 10 grams oil, 18 grams acetic acid anhydride, and a small 
quantity of fused sodium acetate are boiled for one hour and a half, 
the mixture is then washed with distilled water and soda solution, 
and dried with anhydrous sodium sulphate; 5 grams of the acetylised 
oil are saponified with 40 cc. normal potash solution by boiling for 
15 minutes, and thereupon the non-combined alkali titrated back after 
addition of 2 drops phenolphthalein solution. For this purpose not 
less than 14,5 cc. nor more than 16,6 cc. normal acid should be 
required 2). 
^) The boiling point is not required for this purpose. 
^) With regard to this treatment, we would make the following remarks: for 
the acetylisation equal volumes (10 cc.) of oil and acetic acid anhydride are sufficient; 
