152 PLANT AND ORGANIC CHEMISTRY 
sodium carbonate solution was colored pale brown when cold 
or on warming. 
SUMMARY III. ALCOHOLIC EXTRACTS 
Solids extracted. 
Character 
of residue. 
Reaction 
with lit¬ 
mus. 
Quantita¬ 
tive esti¬ 
mation of 
glucose. 
Quantitative 
estimation 
of saccharose 
or other re¬ 
ducible com¬ 
pounds. 
i. Bark of the root... 
9.25 % 0.20% ash 
(red coloring ) 
< matter > 
(crystalline ) 
resin, saponin 
neutral 
0.619% 
0.180 % 
2. Wood of the root.. 
14-30 % 0.10 % “ 
3.80 % 0.15 % “ 
neutral 
1.592% 
0.929% 
3. Green leaf. 
resins, “ 
neutral 
none 
none 
4. Yellow base of leaf 
4.30 % 0.05 % “ 
resin, “ 
slightly 
acid 
traces 
traces 
Extracts (i). 
My attention was not directed to the presence of saponin 
in extract (i), for the characteristic properties which it im¬ 
parted to extracts (2), (3), and (4) were absent; but it was 
evident that saponin was present in the bark, for on boiling 
the latter in distilled water, the presence of the compound was 
indicated. The solution frothed on shaking, and by adding 
a concentrated solution of caustic baryta, saponin-baryta was 
precipitated. 1 
A coloring matter 2 contained in the bark was extracted, 
and imparted to the alcoholic extract a brilliant red color. It 
was precipitated by sub-acetate of lead, and the lead precipi¬ 
tate suspended in water and decomposed by sulphuretted 
hydrogen. The lead sulphide filtrate was evaporated over a 
water bath until the odor of sulphuretted hydrogen was ex¬ 
pelled, and the concentrated liquid was placed over sulphuric 
acid to evaporate slowly. A crystalline residue was obtained. 
On addition of alkalies to the colorless lead sulphide filtrate 
the red color of the original solution was developed. Acid dis- 
discharged the color. Acetic ether took up the red colored 
substance. The acetic ether residue was a red uniform solid, 
1 “Saponin in the Bark of Yucca Angustijolia ,” Science, September it, 
1885. 
2 “A Red Crystalline Coloring Matter,” Science, September n, 1885. 
