62 
ON THE CONSTITUENTS OF LACTUCARIUM. 
albumen was exhausted with alcohol, and the alcoholic ex- 
tract with ether : 
Lactucerine or lactucone, 42.64^ 
Waxy body, readily fusible 3.99 | 48.63 
Vegetable fibre, with a substance which ^ [> per. cent. 
swells in ammonia and is insoluble in V 2.00 | insoluble 
water, alcohol and ether, ) J in water. 
Albumen of a greyish colour, 6.98'] 
Extract soluble in water and in spirit, 27.68 | 51.37 
Aqueous extract, insoluble in alcohol of 'per cent. 
0.S30, 14.96 [soluble in 
Lactucerine, held in solution in water ? j j water. 
by the other substances, 3 * j 
From the bitter extract soluble in water and spirit the 
author obtained lactucic acid in the following manner : 80 
grms. of lactucarium were rubbed to afine powder, and then 
triturated in the cold with SO grms. of pure dilute sulphuric 
acid, and subsequently mixed with 400 grms. of alcohol of 
0.851, filtered, and the filtrate shaken with hydrate of lime 
until a filtered sample no longer afforded a precipitate with 
barytic water nor with oxalate of potash. The filtered 
alcoholic solution was then decolorized with pure animal 
charcoal and evaporated. A brown tenacious mass like 
turpentine separated, which dissolved in boiling water, 
leaving behind a tenacious viscous substance. On decolo- 
rizing the aqueous solution with animal charcoal and eva- 
porating, a mixture of lactucic acid with Aubergier's lactu- 
cine remained ; the latter separated from its solution in 
boiling water on cooling in white crj'stalline scales, and 
the lactucic acid was obtained on evaporation. This latter 
is readily soluble in water and alcohol, difficult to obtain 
crystallized, of a light yellow colour, and strongly bitter 
taste; it has no acid reaction. Solution of caustic soda, 
lime water, barytic water and caustic ammonia colour the 
acid immediately, or after some time, wine-red. A solution 
of sulphate of copper is not precipitated; but on the addition 
