ON THE CONSTITUENTS OF RUSH-PITH. 
93 
The result shows clearly that the substance on hand was cadmium 
bromoxylonate. The presence of xylose in the syrup is thus fully con- 
firmed. 
3) Isolation of Xylose. 
Syrup B was left untouched nearly two months, when, to the agreeable 
surprise of the author, it was found thickly laden with fine crystals. . A little 
amount of 85 % alcohol was added to the syrup, well mixed, filtered with 
suction and washed with absolute alcohol and ether. The sugar thus obtained 
was 4.2 grams in weight and slightly yellowish in color, but, upon recrystal- 
lization from alcohol with use of animal charcoal, it became perfectly white 
and left no ash on ignition. 
1 gram of the carefully dried sugar was dissolved in water and made up 
into 25 c. c. and polarized in 100 mm. tube, in the SOLEIL-VENTZKE Polari- 
scope. Strong bi-rotation was observed. After 24 hours the rotation was 
2.1 on the scale toward the right. The specific rotatory power is 
M 
X 0.346 x 25 
I X I 
+ 1 8.2° (at 21°) 
The mother-liquor filtered off from the crystals formed again a consider- 
able quantity of new crystals in a few days. At the end of a week, when 
the formation of crystals seemed to be at a standstill, the crystals were 
separated by filtration with suction and washed with absolute alcohol and 
ether. The yield of sugar was 1.4 grams. Upon recrystallization from 
alcohol and careful drying, its specific rotatory power was determined and 
found to be 
D = 3.0 x 0.346 X 25 _ 
L J 0.7215 x 2 
+ 1 8.1 0 (at 1 9 0 ) 
The calculated specific rotatory power of 4 % xylose solution at 20°, 
according to TOLLENS n is 
[a] D = 18.095 + 0.06986 p = 1 8.4° 
The sugar under examination is consequently xylose. 
[) Handbuch d. Kohlenhydrate II, Breslau, 1895, p. 70. 
