112 ON' VARIOUS SPECIES OF CINCHONA. 



when shaken. Willi reagents it exhibited the following ap- 

 pearances. 

 Its action with Tincture of gaits formed in it a copious precipitate, which 

 ias ' an excess of the tincture redissolved, and the addition of 



water again threw down. This shows, that the matter sepa- 

 rated by the tannin is not pure!)' animal. 



From the solutions of tartarised antimony and nitrate of 

 mercury it threw down a yellowish white precipitate. To 

 that of sulphate of iron it gave a decided green colour, but 

 nothing fell down. Solution of isinglass pruduced no change 

 in it. It did not redden infusion of litmus. 

 Ueposite from During evaporation this infusion deposited a rosocoh.ured 

 't« -substance on the sides of the dish; and being reduced to the 



consistence of a sirup, it deposited farther on cooling a fresh 

 quantity of a chesnut-brown substance. The filtered liquor 

 was stiil coloured, and contained the salt peculiar to cincho- 

 nas, which will be noticed hereafter. 



The brown substance, washed with a small quantity of cold 

 water, is soluble in warm water and in alcohol ; but very spa- 

 ringly in cold water. Its taste is very bitter. 



In the aqueous solution of this sediment nutgalls form a 

 copious precipitate. Tartarised antimony and nitrate of 

 mercury produce the same effects in this solution as in the 

 infusion of the bark itself. Sulphate of iron is turned green 

 by it. Oxigenized muriatic acid loses its smell when poured 

 into the solution, and presently forms a flocculent precipitate. 

 Isinglass has no effect on it: it is not changed by sulphuric or 

 acetic acid : and when diluted with caustic potash it gives out 

 no smell of ammonia. 



Two bundled and twenty-five grammes [3475 grs.] of this 

 substance, weighed when dry, afforded on distillation a great 

 deal of water, a perceptible quantity of ammonia, and a pur- 

 ple oil, which loses this Co) our on being dissolved in alcohol, 

 but resumes it as the menstruum evaporates by being left 

 exposed to the air. 



They left in the retort 11 decig. [17 grs.] of coal, which 

 yielded by incineration 1 dec. [1'olgrs.] of ashes soluble 

 With effeivescence in muriatic acid, and the solution of which 

 yielded lime and iron. 



ft 



