942 INDIAN MEDICINAL PLANTS. 



hydrates causes it to assume immediately a cherry-red colour, which quickly 



passes into brick-red and olive-green. 



Owing to the insolubility of the crystals in water a proof spirit solution 

 was used in applying the following tests : — 



1. A solution of silver nitrate in proof spirit produced a bluish-black 

 colour immediately, and after the liquid had stood for a few minutes black 

 particles of reduced silver were precipitated. 



2. A solution of neutral acetate of lead in proof spirit gave a light-red 

 bulky precipitate insoluble in boiling acetic acid. 



3. Lime water imparted an orange colour, which quickly changed to olive- 

 green, followed by a precipitate of the same colour. 



4. An aqueous solution of copper gave a golden yellow colour, quickly 

 followed by a dirty brown precipitate, the supernatant liquid being distinctly 

 greenish. 



5. Solution of ferric chloride (acid) produced a brownish-red colour, which, 

 in a few minutes, turned smoke-colour. 



6. Solution of subacetate of lead gave a golden yellow precipitate. 



7. An aqueous solution of mercuric chloride produced a white precipitate. 



8. An aqueous solution of permanganate of potash, acidified with sulphuric 

 acid, was instantly decolorized. 



9. A solution of the crystals in proof spirit did not reduce Fehling. 



The authors say : — " We have attempted to hydrolyse this body, by subject- 

 ing a strong alcoholic solution to the prolonged action of 10 per cent, solution 

 of sulphuric acid at a boiling temperature, but without success. 



" We have also inquired into its nature and centesimal composition, but 

 the results so far obtained are not sufficiently conclusive to be incorporated 

 in this paper. We hope to be able to publish shortly a supplementary note 

 dealing with points in process of investigation. Mean while, we propose that 

 this interesting principle be designated Oroxijlin." 



C. The marc left after exhaustion with petroleum spirit and ether was 

 percolated with cold absolute alcohol. The residue resulting from the 

 distillation of the spirit was treated with cold proof spirit, which took up 

 the greater part of it. The insoluble portion dissolved readily in boiling 

 proof spirit, and, on examination proved to be largely composed of the 

 yellow crystalline body oroxylin. The cold proof spirit solution of the 

 alcoholic residue was evaporated to dryness and the extract treated with 

 water and filtered. The filtrate was treated successively with neutral and 

 basic acetate of lead, and the precipitates after washing were suspended 

 in water, decomposed by a current of sulphuretted hydrogen and the result- 

 ant plumbic sulphide removed by filtration. Sulphuretted hydrogen was also 

 passed through the filtrate from the basic or plumbic acetate and the 

 precipitated lead sulphide removed by filtration. 



The three liquids thus obtained, which for convenience may be denomi- 

 nated i., ii., iii., were then evaporated down and the respective residues 

 examined. 



(i.) It was dissolved in the smallest quantity possible of cold water and 

 diluted with many times its volume of alcohol. After setting aside for 



