ON VARIOUS SPECIES OF CINCHONA. ]]5 



The part not soluble in alcohol was of an ochre red, and Portion not so- 

 blackcned by exposure to the air. It was redissolvable in llol< 

 water; and its solution precipitated neither isinglass nor galls: 

 but it precipitated tartarised antimony and nitrate of mercury, 

 and turned sulphate of iron green. 



Ten grammes [154f grs.] of this substance insoluble in 

 alcohol being distilled afforded ammonia, and a coal that 

 weighed 41 cent. [0| grs.] 



A bark sold me without any name*. 



A hundred grammes of this bark macerated for twenty- Another spe- 

 four hours did not give the water so deep a colour as the pre- ^thepreceed- 

 ceeding species, and its astringency was less, but it was more ing. 

 bitter. 



It perceptibly reddened infusion of litmus; precipitated 

 neither with galls nor tartarised antimony ; but formed a pre- 

 cipitate with isinglass and nitrate of mercury, and turned 

 sulphate of iron green. 



This species exhibited all the characters in general of the 

 preceding, and should be placed in the same class. 



The decoction of the residuum showed no difference from 

 the infusion. 



Spec. 11. True pit ton bark. 



This species, which was given me by Mr. Solome, an emi- Pittontark. 

 licnt apothecary in Paris, greatly resembles in colour, form, 

 and bitterness the cinchona of St. Domingo, which was ana- 

 lysed by Mr. Fourcroy about fifteen years ago. 



A hundred grammes of this bark, treated like the other, 

 imparted to the water a red colour like that of venous blood. 

 Its taste is more bitter and disagreeable than that of the I f * action with 

 others. Tincture of galls, tartarised antimony, nitrate of re fce 

 mercury, and sulphate of iron, produced copious precipitates 

 with this infusion of cinchona. Isinglass produced no change 

 in it. It was precipitated by oxigenised muriatic acid, but by 

 no other. 



The infusion left by evaporation a residuum, which partly 

 dissolved in alcohol, communicating to it a fine red colour. 



* Jt had all the characters of the cinchona magnifolia [grandifolia]. 

 I 2 The 



