— 75 — 
they are boiled for one to one and a half hours with the addition of a small quantity 
of fused sodium acetate. After boiling, the acetylisation mixture is first of all left to cool ; 
a small quantity of water is then added, and the whole heated for lo to 15 minutes 
on a water bath, in order to decompose the excess of acetic acid anhydride. It is 
again left to cool, the oil separated from the aqueous liquid in a separating funnel, 
and washed with water until it shows a neutral reaction. The oil thus treated, after 
being dried with dehydrated sodium sulphate, is ready for the further treatment. 
For the saponification, alcoholic potash solution is more suitable, as it saponifies better 
than the aqueous liquor, a matter of great importance for santalyl acetate which is 
comparatively difficult to saponify. For the same reason, one hour's heating on 
the water bath is advisable. 
The statements regarding the consumption of alkali are not correct; the saponi- 
fication numbers 262,08 and 285,6 which result from it, refer to an alcohol of the 
formula Cj^H^gO (linalool, geraniol, etc.) whereas santalol has the formula Cj^Hg^^O 
(compare Report October 1900, 58). A santalol - content of 90 to 100 per cent, 
corresponds to the saponification numbers 195,5 to 213,7, equal to a consumption 
of normal liquor of 17,46 to 19,08 cc. with 5 grams oil. 
Oil of Savin (Sabinae essentia). Colourless or yellowish; = 0,9 1 o 
to 0,930; soluble in one-half volume by weight of alcohol. 
•Oil of Wild Thyme {Serpylli essentia). Colourless or yellowish; 
d^^o= 0,890 to 0,920. 
Thymol. Colourless, transparent crystals; very sparingly soluble 
in w^ater, readily soluble in alcohol, ether, chloroform, and the aqueous 
solutions of caustic alkalies; heavier than water ^); melting point 50° 
to 51°; boiling point 230°. 
For the rest the test corresponds to that of the German Pharmacopoeia. 
^) Molten thymol floats on water. 
Oil of Turpentine {Terebinthinae essentia^. Colourless; dj50 = 
0,850 to 0,870!); boiling point 155° to 162°; soluble in 12 parts 
alcohol, the solution should show no acid reaction. 
^) The limits in this case might be narrower: d^^o = 0,860 to 0,870. 
Wilbert^) discusses the essential oils from the point of view of 
the United States Pharmacopoeia. In view of the fluctuating com- 
position and the large differences in the constants of natural oils, and 
also wdth reference to their generally higher prices, Wilbert, following 
the example of the German and Swedish Pharmacopoeias, advocates 
the introduction of the active principles of the oils, such as benz- 
aldehyde, eugenol, methyl ester of salicylic acid, or also of the syn- 
thetic oils, such as synthetic neroli oil. 
^) Amer. Journ. Pharm. 75 (1903), 155, 218. 
