278 A CHEMICAL STUDY OF 



precipitate which formed was collected on a weighed filter. It was dried, and weighed. 

 The precipitate and filter were incinerated in a weighed poi'celain covered crucible, and 

 the percentage of ash calculated. 



Weight of precipitate b}' stronger alcoliol yielded l-'^O per cent. 



" ash yielded 0-34 " 



CarhJiydrates. 



The filtrate and wash-alcohol fi-om the gum precipitate were concentrated at a low 

 temperature, and the residue was mixed with four volumes of stronger alcohol. The 

 precipitate was rapidly filtered off, and the percentage of carNiydrates calculated 

 gravimetrically in the usual way, from the amount of cupric oxide reduced from Feliling's 

 solution. It yielded 2.75 per cent. 



Carhhydrate Filtrate. 



A portion, representing a certain volume of the aqueovs extract, of the carhhydrate 

 ■filtrate was evaporated, dried, and weighed. It yielded 7.65 per cent, of the total solids 

 of the aqueous extract residue. A lalo^yll weight of the carhhydrate filtrate residue was 

 dissolved in water and heated over a water-bath with Feliling's solution, and the 

 amount of glucose present estimated gravimetrically from the weight of the cupric 

 oxide. It was estimated as 4.47 per cent. Another portion of the carM?/(7r«fe^^^rafc 

 residue was boiled with 83 per cent, alcohol. A precipitate formed on cooling, which 

 was collected on a weighed filter, dried, and weighed. It yielded 1.98 per cent. The 

 83 per cent, alcohol precipitate was identified as saponin by the usual tests. The carh- 

 hydrate -filtrate residue was precipitated b}'- acetate of lead and the precipitate examined 

 qualitatively for organic acids. The lead precipitate was decomposed by sulphuretted 

 hydrogen and filtered, and the filtrate concentrated over a water-bath, and mixed 

 with lime-water until turbid. The turbidity did not clear on adding dilute acetic acid. 



The aqueous extract was examined for tamiin, and with negative results. Calcium 

 oxalate was present. 



Extract (3), the Qreen Fart of the Leaf. 



The residual powder was dried from all traces of alcohol, and cold distilled water 

 was allowed to slowly percolate through the powder. The extract was colored, and 

 slightly acid in reaction. A definite volume of the extract was evaporated, dried, and 

 weighed, and tlic ash calculated from incinerating a known weight of the residue. 



TOTAL SOLIDS. 



A'pieons residue dried between 100° C and 1 10° 4.n.T per cent. 



" ash 0.40 " 



