APPENDIX. 191 



ACANTHACE^. 



Note on the presence of a Cholesterol in the roots of 



Hygrophila spinosa- . 



In the Pharmacographia Indtca, one of us described the physical 

 properties of a principle isolated from the roots of the BygropJiila 

 spinosa, which was not unlike a cholesterol. Subsequently, through 

 the kindness of Dr. Dymock, we obtained a large supply of the roots, 

 and were able to separate a sufficient amount of the material to 

 admit of its thorough purification an-d ultimate composition being 

 determined. 



For ultimate analysis the principle was crystallized from light 

 petroleum ether, and the combustion made in an open tube in a 

 current of oxygen. The tube had been in use some time and was 

 in very good woi'king order. The results obtained led to the follow- 

 ing formula : 



Calculated for 



Found. 



c 



H 

 O 



afi 



44! 



«•• 



• • ■ 



312 83-86 83-80 



4t 11-82 12-02 



16 4-32 4-18 



372 100-00 100-00 



At 175° 0, (uncor.) the cholesterol commenced to soften, and 

 melted at 184° (uucor.). The fusing point would appear to be higher 

 than that of any cholesterol hitherto isolated. We were unfor- 

 tunately unable to detennine the specific rotatory power. 



In purifying the cholesterol an alcoholic extract of the root was 

 dried and exhausted with ether. The dry ether extract was treated 

 with dilute sulphuric acid, and the insoluble residue taken up by 

 ether. The ether extract was next boiled with aqueous caustic 

 potash, the solution evaporated to diyness, and extracted with 

 petroleum ether. The petroleum ether extract was boiled for some 



dry 



um 



extracted with petroleum ether. The petrol 

 low colom-, and in order to decolourize it, it was dissolved in absolute 

 alcohol, and the solution agitated with purified animal charcoal ; 

 this, however, failed to remove the whole of the colour, and the 

 following experiment was adopted. The alcohol was evaporated off. 



