276 A CHEMICAL STUDY OF 



TOTAL SOLIDS. 



Aqueous residue dried between 100° and IW^ C 4.00 per cent. 



ash 2.05 " 



Oum. 



One volume of the aqueous extract was mixed with two volumes of Squibb's 

 stronger alcohol. The mixture was kept in a cool place for twenty-four hours, and the 

 precipitate which had formed was collected on a weighed filter, Avashed with 06 per 

 cent, alcohol, dried, and weighed. The precipitate and filter were incinerated in a 

 weighed porcelain crucible, and the weight of the filter being deducted, the percentage 

 of ash was determined. 



Weight of precipitate by stronger alcohol yielded 2.0 per cent. 



" " ash yielded 0.3 " 



Another poi'tion of the aqueous extract was precipitated by stronger alcohol, and 

 the precipitate consisted of gum and albuminous substances. It was incompletely 

 soluble in water. The soluble matter was gum, it was recovered from solution by 

 evaporating the liquid to dryness. The gummy residue was almost completely solu- 

 ble in cold water. It was precii^itated from a concentrated aqueous solution by 

 stronger alcohol ; basic acetate of lead precipitated it as a fiocculent precipitate. Borax 

 did not thicken the gum solution, and ferric chloride and sodium chloride solutions did 

 not precipitate it. The gum was boiled with dilute acid, and heated over a water bath 

 with Fehling's solution which it reduced. A few drops of hydrochloric acid and 

 stronger alcohol were mixed with the concentrated gum solution for the separation of 

 arabin. It was not separated. 



Carhliydrates. 



The filtrate and wash alcohol from the gum precipitate were mixed, and evapo- 

 rated to a syrupy consistency at a temperature of 70° to 8U° C. The concentrated sohi- 

 tion was treated Avith four volumes of stronger alcohol, and the resulting precipitate 

 of carbhydrates rapidly filtered off. It was soluble in water. It was not precijji- 

 tated from aqueous solution by basic acetate of lead, and by this means it was dis- 

 tinguished from vegetable mucilage. The carhhydrates were boiled with dilute acid, 

 and the solution was rendered alkaline, and heated over a Avater bath Avith Fehling's 

 solution. The latter was reduced. The percentage of carbhydrates as estimated, 

 amounted to 0.2 per cent. An aqueous carbhydrafe solution Avas mixed Avith a solu- 

 tion of barium in 40 i)er cent, alcohol. It yielded no precipitate. 



