HELIOTROPE. 189 
washings are added together and the whole distilled over an open 
fire. The first portions of the distillate contain the largest 
proportion of piperonal, the greater part of which crystallizes out 
on cooling. The remainder may be obtained by agitation with 
ether *. 
Piperonal crystallizes from water in colourless, transparent, 
highly lustrous prisms, an inch long. It is sparingly soluble in 
cold water, easily in cold alcohol, and in all proportions in boiling 
alcohol or ether. It melts exactly at 37° and boils without de- 
composition at 263°, forming a vapour which has a sp. gr. of 5:18 fF. 
Tiemann and Haarmann state { “that the odour of piperonal is 
possessed by ‘ vanillon,’ a kind of vanilla, which forms thick, fleshy 
capsules and is obtained from the West Indies. This sort of vanilla 
is employed in perfumery for the preparation of essence of 
heliotrope ; it contains no piperonal, but vanillin and an oil which 
is not yet identified. The perfumers, in preparing essence of 
heliotrope, add a little of this oil to the extract of vanillon. If a 
little be added to a solution of pure vanillin, both substances can 
be recognized by their smell for some time, but after standing for 
months the mixture acquires the smell of heliotrope.” 
The perfume of “ Heliotropine ” is completely destroyed by the 
action of direct sunlight; it is also injured by heat ; it should 
therefore be stored in a cool place in the dark, such as a cool cellar, 
and be kept in yellow glass bottles, the yellow glass intercepting 
the chemical rays. 
HawtTHorn. 
Under the pseudonym “ Aubepine” a preparation having the 
odour of Hawthorn (Crategus oxycantha) has recently been brought 
out by a Paris firm as a novelty, but it appears to be a definite 
chemical body, long known to chemists as anisic aldehyde (Para- 
methoxybenzaldehyde),C,H,O,. Cahours found § that it is formed, 
together with anisic acid, by the oxidation of oil of anise. It can 
be prepared by gently heating the oil of anise for about an hour 
with three times its volume of nitric acid of sp. gr. 1:106 (14° 
Beaumé). The heavy oil which is thus formed is washed with 
* Chemiker Zeitung, Feb. 1884, and Ann. Ch. Pharm. clii. p. 35. 
+ Ber. Deutsch. chem. Ges. x. p. 1274. 
} Ibid. ix. p. 1287. 
§ Ann. Chim. Phys. [3] xiv. p. 484, and ibid. xxiii. p. 354. 
