STUDY OF YUCCA ANGUSTIFOLIA 147 
they were decomposed and melted, leaving a dark-colored 
liquid. Several attempts were made to dry these crystals, with¬ 
out success. A few of the crystals were recovered from the 
solution, and tested for alkaloids; no reactions were obtained 
with the usual reagents for them. 
Glucose was estimated from the aqueous extract. The liquid 
was heated over a water bath with Fehling’s solution, and the pre¬ 
cipitated red cuprous oxide was thrown upon a weighed filter, 
dried, and incinerated. The glucose was estimated gravimetri- 
cally by calculating the amount of cupric oxide. It yielded 
0.619 P er cent. A portion of the aqueous extract was boiled 
with acid, neutralized, and heated over a water bath with Feh¬ 
ling’ s solution to calculate, by difference, saccharose or other 
reducible compounds, and by this method 0.18 per cent, was 
obtained. 
The alcoholic extract was described as being deeply colored. 
This coloring principle 1 was completely precipitated by sub¬ 
acetate of lead. The lead precipitate was collected on a 
filter, suspended in water, and decomposed by sulphuretted 
hydrogen, filtered, and the filtrate freed from all odor. It was 
allowed to evaporate slowly over sulphuric acid. The residue 
was a brownish-gray mass, interspersed with fine crystals 
which radiated from a nucleus. The mass was weighed and 
gave 3.27 per cent, of solids. Another portion of the alcoholic 
extract was agitated with water and acetic ether. The color¬ 
ing matter was taken up by the acetic ether, and on evapo¬ 
rating a red-colored substance was recovered. It was dried 
and weighed, yielding 2.2 per cent. This red-colored residue 
was perfectly soluble in cold water. This solution was tested 
with the following reagents: It gave with potassium bichro¬ 
mate a creamy-colored precipitate; ferric chloride, a yellow¬ 
ish-green precipitate; ferrous sulphate, a reddish-brown pre¬ 
cipitate; stannous chloride, no precipitate, a yellow cloudy 
liquid; alum, a cloudy solution; neutral acetate of lead, a 
slight precipitate. The red color of the coloring matter was 
brought out on addition of alkalies. It was destroyed by 
acids. 
1 “ A Red Crystalline Coloring Matter,” Science, September n, 1885. 
