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tion of xylan from jute. The ground straw was extracted with 
2 percent solution of ammonia and then digested 48 hours with a 
6 percent solution of KOH, 6 liters to each original half kilogram of 
straw. The extract was pressed out, filtered through cloth and the 
xylan precipitated by adding an equal volume of 95 percent alcohol 
to the solution. It was then filtered and the precipitate neutralized 
with a solution of HCl in alcohol. The xylan was washed in a Buch- 
ner funnel with 60 percent alcohol until the washings gave no test for 
chloride with silver nitrate. It was then dried with absolute alcohol 
and ether, ground up in a mortar, passed through a fine sieve and was 
ready for use. In order to prove that the preparation was a compound 
of xylose sugar, a quantity of the xylan was hydrolyzed with sulphuric 
acid according to the method of Wheeler and Tollens.^^ 
The mixture of xylan and 5 percent sulphuric acid was heated on 
the steam bath for six hours. The acid was then neutralized with 
magnesium-free calcium carbonate, filtered, and the filtrate evaporated 
nearly to dryness under reduced pressure. The residue was taken 
up with hot alcohol and treated with animal charcoal to decolorize. 
The solution was concentrated in a vacuum desiccator over sulphuric 
acid and in a few days the sugar crystallized out. It was recrystal- 
lized from alcohol several times. The crystals were white and had 
the characteristic form of xylose. They melted at I43°-I44° C, 
uncorrected. The sugar had a specific rotation, [a]D, of + 18.92 as 
compared with + for xylose. It reduced Fehling's solution, 
formed furfurol which was precipitated as the phloroglucid when 
boiled with a hydrochloric acid solution of phloroglucin. The osazone 
was prepared in the usual way and crystallized as bright yellow needle- 
like crystals, insoluble in cold water, soluble in hot, and melting at 
160° C,, uncorrected, as compared with 160° C. for xylosazone according 
to Tollens.^^ The sugar was apparently xylose. 
In the preparation of xylan, Salkowski's method^^ was also used. 
24 Wheeler, H. J., und Tollens, B. Ueber die Xylose oder den Holzzucker, eine 
zweite Penta-glycose. Zeitschr. Vereins Riibenzucker-Industrie Deutsch. Reichs 
39: 848-868. 1889. 
25 Parous, E., und Tollens, B. Ueber die Mehr- oder Weniger-Drehung (Multi- 
Rotation oder sog. Birotation und Halbrotation) der Zuckerarten. Liebig Ann. 
257: 160-178. 1890. 
26 Tollens, B., et al. Untersuchungen iiber Kohlenhydrate. Zeitschr. Vereins 
Riibenzucker-Industrie Deutsch. Reichs 41: 885-911. 1891. 
27 Salkowski, E. Uber die Darstellung des Xylan. Zeitschr. Physiol. Chem. 
34: 162-180. 1901-02. 
