STUDY OF YUCCA ANGUSTIFOLIA 161 



of it was evaporated, dried, and weighed. The ash was de- 

 termined from a part of the aqueous extract residue. 



TOTAL SOLIDS. 



Aqueous residue dried between 100 C. and 110 C 11.35 per cent. 



" ash 3.10 " 



Gum. 



One volume of the aqueous extract was mixed with two 

 volumes of stronger alcohol. The precipitate was collected, 

 washed with 66 per cent, alcohol, dried, and weighed. The 

 ash was calculated from incinerating the precipitate, and de- 

 ducting the filter. 



Weight of precipitate by stronger alcohol yielded 3-850 per cent. 



ashyielded 0.676 " 



Carbhydrates. 



The filtrate and wash alcohol from the gum precipitate were 

 concentrated at a low temperature. The residual liquid was 

 mixed with four volumes of stronger alcohol, when a precipi- 

 tate formed, and was rapidly filtered off. The carbhydrates 

 were dissolved in water boiled with dilute acid, and the liquid 

 rendered alkaline and heated over a water-bath with Feh- 

 ling's solution. The amount of carbhydrates was estimated 

 gravimetrically in the usual way. It gave 2.95 per cent. 



Carbhydrate Filtrate. 



The filtrate residue was examined for glucose, and traces 

 of it were present. The -filtrate residue was precipitated with 

 acetate of lead, and the lead precipitate was dissolved in water 

 and decomposed by sulphuretted hydrogen. The lead sul- 

 phide filtrate was tested quantitatively for organic acids, and 

 a turbidity formed on adding to the filtrate lime-water. It 

 was not completely cleared by acetic acid. 



Negative results followed tests with alcoholic methyl-violet 



