VANILLA. 163 
and thus obtained vanillin. The elaborate and important original 
paper * was abstracted in French in the ‘Comptes Rendus’ of the 
French Academy, Ixxviii. p. 1365, and in English in the Pharma- 
ceutical Journal, [3] iv. p. 996. 
Among the numerous glucosides of vegetable origin there is one, 
Coniferin, which for a long time escaped the notice of chemists 
and physiologists, although it is found in considerable quantity in 
the members of one of the most widely distributed orders of plants. 
This body was first found in 1861 in the juice of the cambium of 
the Larix Europea by Hartig, who for that reason called it 
“Taricin.” Afterwards, its presence being recognized in the 
cambium of all the pines, the name of ‘“ Abietin ”’ was conferred 
upon it. Finally, as it appeared to exist in all the Conifer, Kubel, 
who was the first to study it chemically, with the consent of Hartig 
again changed the name to Coniferin. 
Coniferin may be prepared in the following manner. At the 
time of the formation of the wood, in the spring or early summer, 
such conifers as Abies excelsa and A, pectinata, Pinus strobus and 
P. cembra, Larix Europea, etc., are felled, and the trunks are 
sawn into several pieces and afterwards barked. The juice of the 
cambium is collected by scraping the wood with a sharp instrument, 
such as a piece of glass. This juice is boiled and filtered to elimi- 
nate albuminous matters, then evaporated to about one fifth its 
original volume. After a time it deposits brown-coloured crystals, 
which are pressed, purified, and decolorized by repeated recrys- 
tallizations and treatment with animal charcoal. The greater part 
of the impurities may be removed by treating the brown solution 
of coniferin, whilst still warm, with small quantities of acetate of 
lead and ammonia; the resinous and colouring matters being pre- 
cipitated whilst the coniferin remains in solution. Excess of 
acetate of lead may be easily removed by means of a current of 
carbonic-acid gas. Coniferin is slightly soluble in cold water, 
more soluble in hot water and in alcohol, but is not soluble in ether. 
It crystallizes upon cooling in white, transparent, brilliant, sharp- 
pointed crystals. These crystals become opaque and dull in con- 
tact with air, losing part of their water of crystallization, which is 
driven off completely at 100°C. The aqueous solution of coniferin 
is bitter, levogyrous, and does not reduce Fehling’s solution, even 
after prolonged boiling. Moistened with carbolic acid or concen- 
* Ber. Deutsch. chem. Ges, 1874, p. 608. 
