‘ pes 2 5 e 
deposit is obtained at once on cooling. The safest way quickly to obtain crystalline — 
in chloroform. From chloroform, or, better still, from a mixture of chloroform and 
_ of water, strongly stirring the while. A flocculent, pure white substance is separated 
The firm of Rubeck —a _ thoroughly English- ‘sounding name, to be sure — which ee 4 
imperfection of the tee hagas is at fault we cannot jndee, but for the benefit ‘" 
certain conifers, a term used for the resin or gum which exudes spontaneaaan f 
the tree, and which is therefore a physiological secfetion, has a different chem 
composition. ae 
To eliminate the acids, styrax is dissolved in 70 to 80 per cent. alcohol onthe’ 
water-bath and kept in the cold over night. A dark oil will be found separated wie 4 
the bottom of the vessel. The supernatent clear dark-yellow, alcoholic solution is 
next precipitated with an alcoholic neutral acetate of lead solution. On heating the — 
strong precipitate is dissolved again almost completely in the precipitation liquid and 
on cooling it separates in crystalline form. This solubility is due to the esters and_— x 
terpenes contained in styrax. In pure alcohol the acetate of lead deposit is practically 
insoluble. The original solution may also be precipitated hot, in which case a crystalline 
products is to dry the precipitate thoroughly whereupon it dissolves almost completely — 
acetic ester it may be recrystallized. The lead salt thus obtained is dissolved in glacial ! 
acetic acid with a slight addition of alcohol and is poured slowly into a sufficiency — 
which coagulates on warming and becomes quite hard and brittle upon cooling. By — 
repeated recrystallization from a mixture of glacial acetic acid with acetone or methyl 
alcohol and finally from methyl alcohol alone crystals of the m. p. 140 to 150° are 
obtained. By purification with the sodium salt the author succeeded in preparing 4 b 
from these crystals an acid of the m.p. 210 to 211° which proved to be identical with — . 
d-pimaric acid. The second substance forming the bulk of the original acid mixture s 
crystallizes from dilute methyl alcohol and melts at 158 to 165°; ap —39° 36’. Indications 
in literature on the melting point of abietinic acid vary considerably, more especially — 
so in earlier publications. In the author’s opinion the acid of the m. p. 158 to 165° — 
appears to be identical with abietinic acid. Its behaviour when heated, in which 
process it develops carbonic acid and forms butyric acid, points to abietinic acid. 
Thymol. A “highly important” piece of news, from which it is palpable that the q 
German. chemical industry is now finally and completely beaten, comes from England’). — 
Pharmacopeeia)*), has prepared thymol crystals from thyme oil, the onnede bein 
particularly colossal dimensions that a show-piece weighing 650 g. was reproduced — 
the form of an outline picture, needless to say with the required) amount of tom- 
beating. Unfortunately, said picture does not convey the impression of a beautiful yi 
formed crystal at all, but rather of an irregular crystalline mass. In how far th 4 
ove — 
1) Chemist and Druggist 88 (1916), 676. — ?) See Report October 1915, 5A. 
4 
