38 
LACTUCA VIROSA AND SATIVA. 
quently not be extracted by water, the following experi- 
ments were made on some pounds of the dried plant Lac- 
tuca sativa, collected in the flowering season. The plant, 
cut into small pieces, was treated with warm water con- 
taining nitric acid, then expressed, filtered, and the acid 
saturated with carbonate of ammonia, then boiled, filtered, 
precipitated with basic acetate of lead, the precipitate 
washed and decomposed with sulphuretted hydrogen, which 
operation was again repeated ; finally, the colorless solution 
was evaporated and set aside in a warm place. After a 
considerable length of time a crystalline mixture was ob- 
tained in a syrupy fluid, which collected carefully, brought 
on to bibulous paper and recrystallized, gave prismatic 
crystals. 
A portion of the acid; saturated with caustic ammonia, 
did not afford any oxalic acid, but only succinic and citric 
acids, which yielded, on separation by means of lime-milk 
and decomposition of the lime salts, pure crystallized suc- 
cinic and citric acids. The quantity of succinic acid which 
was obtained this time was considerably greater than pre- 
viously. — Ibid, from Jlrchiv. der Pharm. 
