various Species of Cinchona. 43 



low bark precipitates the emetic, is combined with a certain 

 substance found in the gray cinnamon cinchona and in tan : 

 but these infusions, thus nmtually precipitated, still precipi- 

 tate abundantly the solution of glue; whence again it fol- 

 lows, that the principle which in these two cinchonas preci- 

 pitates glue is not the same as that which decomposes the 

 emetic : what confirms this opinion is, that the infusion of 

 the yellow cinchona, precipitated as completely as possible 

 by glue, and afterwards filtered, still precipitates the emetic, 

 • — a little less abundantly, however. 



\Vc cannot attribute the precipitation of the emetic to the 

 excess of glue, for this animal substance causes no change 

 whatever in emetic. 



The precipitate which is formed by the infusions of the 

 yellow and gray cinnamon cinchonas, mixed together, is 

 brown ; it dries easily, bubbles up by heat, exhales a smoke 

 which has no pungency, and which has some analogy with 

 that of animal matters : it leaves a spongy and light cliar- 

 coal. 



Sixth Species. — Gray Cinchona*. 



It was in very slender and rolled barks, and must have 

 been taken from the branches, or from vcrv young trees. 

 It would seem to be of the species of the loxa cinchona, 

 which will be described in the course of this memoir. 



The infusion of this species had a red colour like Malaora 

 wine, and an astringent and bitter taste; it precipitated abun- 

 dantly glue in white; infusion of tan in reddish yellow; in- 

 fusioaof yellow cinchona in gray ; emetic in flakes of yel- 

 lowish white ; sulphate of iron in green ; and acetate of lead 

 in white. It did not precipitate sulphate of copper nor aa 

 infusion of Santa-F(i cinchona. This bark possesses the 

 tcbrifugc property in a very high degree. 



Seventh Species.— F/«? Gray Cinchona f. 

 The infusion of this species of bark has a red colour like 



• Thi« ipecie* was traotmutcd to me by M. Bouillon-Lagranf^c. 

 I Tl.is setms to b« the white cinchona of SanU-F«, brought by M. Hum. 

 boldt, which will be aftcnhirdj described. 



Malaga 



