ON VARIOUS 3FECIES OF CINCHONA. J J J. 



the cinnamon gray bark, oriv.n with sulphate of iron. On 

 the other metallic solutions it acts like other species of cin* 

 chona. 



Spec. 6. Gray bark. 



This, which I had from Mr. Bouillon Lagrange, was very Qraybarfc, 

 thin and convoluted ; and apparently from twigs or very 

 young trees of the Loxa bark, which will be mentioned fur- 

 ther on. 



The infusion of this species had the red colour of Malaga lis action \yUfo 

 wine, and an astringent bitter taste. It gave a copious white rea 8 e - $• 

 precipitate with isinglass, reddish yellow with infusion of tan, 

 gray with infusion of yellow bark, yellowish white and floc- 

 culent with emetic tartar, green with sulphate of iron, white 

 with acetate of lead.. It did not precipitate sulphate of cop- 

 per, or infusion of Santa Fe bark. It must possess thefebri- Highly fehfj* 

 fuge property in a high degree. ?% Q - 



Spec. 7- Flat gray hark*. 



The infusion of this bark has the colour of Malaga wine, Flat gray barfe. 

 •and a flat taste, without any astringency or bitterness. 



From the infusion of yellow bark it throws down a copious, j ts action ^\\\\ 

 brown, flocculent precipitate. To the solution of red sul- ^S?^? 

 phate of iron it gives a fine green colour, and in a 'few mi- 

 nutes a precipitate of the same colour is thrown down. Nei- 

 ther tartarised antimony, isinglass, nor cinnamon gray bark 

 produces any change in its infusion. 



These appearances indicate, that it is not a true cinchona; Not a cmcl>9* 

 or, if it belong to the genus, at least it has not its chemical na » 

 properties ; whence we may presume, that it does not possess 

 the same medicinal virtues. 



Spec. 8 . Yellow [ w h i te] bark, cinchona pubescens of Vahl. 



A hundred grammes of this bark in fine powder macerated white bark, 

 four and twenty hours in distilled water afforded a transparent 

 liquor of it golden yellow colour, very bitter, and frothing 



* This appears to be the white cinchona of Santa Fe brought oyer by 

 Mr. von Humboldt, which will be noticed further on. 



when 



