ON THE CONSTITUENTS OF RUSH-PITH. 
Quantitative Analysis. 
Analysis was made by the Weende method, commonly adopted for food 
stuffs. The results follow : 
Air-dry Water-free 
substance. substance. 
X 
X 
Water 
7-i5 
— 
Ash 
4-39 
4-73 
Protein 
i-73 
1.86 
Fat 
6.55 
7.05 
Crude fiber 
33-i6 
35-72 
Nitrogen-free extract .. 
47.02 
50.64 
Pentosan-free fiber 
25-35 
27.30 
Pentosan 
35-02 
37-72 
Methyl pentosan 
2.82 
3-04 
The crude fiber obtained by the Weende method contained still a 
■considerable amount of pentosan, as could be easily shown with phloroglucin 
and hydrochloric acid. KÖNIG’S method ( l.c .) was consequently tried to 
determine pentosan-free fiber by treating the substance with glycerin of 1.23 
sp. gr., and containing 2 grams of sulphuric acid in ico c.c. The fiber 
obtained by this method gave no pentosan reaction with phloroglucin and 
hydrochloric acid, nor did it show that of methyl furfurol on testing its 
distillate by the spectrum reaction. Treated with zinc-chloride-iodin solu- 
tion, the fiber assumed at once a dark blue color, indicating the presence of 
free cellulose. 
Determination of pentosan and methyl pentosan was made according 
to the method of ELLETT and TOLLENS. 1 ' The substance was distilled with 
hydrochloric acid of 1.06 sp. gr., adding 30 c.c. of the acid into the distilling 
flask, whenever 30 c.c. were distilled over. The distillation was continued 
until the distillate gave no more characteristic reactions of furfurol and 
1) Berlin, Ber. D. chem. Ges. 38 (1905) pp. 492-499. 
