OIL FROM SEEDS OF BURSARIA SPINOSA. 403 



barium carbonate and the whole mass evaporated to a paste 

 at a low temperature on the water-bath. Alcohol was added 

 to the residue and the evaporation repeated. The pasty 

 residue was then extracted several times with alcohol. 

 The alcohol was removed by evaporation when about 10 cc. 

 of a dark coloured very viscous liquid remained. This 

 viscous liquid had the following properties: — 



(a) it readily mixed with water, 



(6) it readily mixed with alcohol, 



(c) it was insoluble in ether, 



(d) it gave a translucent mark on paper which was 



removed by water, 



(e) on heating with KHS0 4 a gas having an irritating 



effect on the nostrils and eyes was evolved. On pass- 

 ing tliis gas into ammoniacal silver nitrate and 

 warming the solution, a silver mirror was obtained. 

 This viscous residue, therefore, consists mainly of 

 impure glycerol. Several attempts were made to 

 further purify this glycerol by distilling under reduced 

 pressure, but owing to the bumping and frothing, 

 they were unsuccessful. 



Examination of the unsaponifiable material extracted 

 from the soap by petroleum ether.— The residue left on 

 removing the petroleum ether was a yellowish liquid while 

 hot, but on cooling it formed a soft buttery mass in which 

 crystals could be distinguished by means of the microscope. 

 The crystals were of two kinds (a) colourless rhombic plates 

 / > and (b) tufts of needle-like crystals *, In order to 

 make sure that the residue contained no unsaponified oil, 

 the residue was heated on the water-bath with a few cc. 

 of alcoholic potassium hydrate. The alcohol was removed 

 by evaporation and the dry residue again extracted by 

 petroleum ether. The residue was similar to that obtained 

 from the first extraction. It was dissolved in alcohol and 

 allowed to stand several hours when a mass of crystalline 



Z-Dec. 1. 190P. 



