ON VARIOUS SPECIES OF CINCHONA. |0A 



must he different from that which decomposes tartarised 

 antimony. 



The hark left after this infusion being boiled in water, the Residuum de- 

 decoction Had utmost exactly the same effects on the reagents cocte< *' 

 above enumerated: the only difference between them was, 

 that the decoction became turbid on cooling, furnished a 

 smaller quantity of precipitate, and this separated from the 

 liquor more speedily. 



I have to add, that both of them threw down from the so- with other 

 lotion of sulphate of copper a reddish yellow precipitate, and reagents 

 from that of acetate of lead a yellowish white. 



Spec. 2. Santa Fe bark. 



This bark, which is lately introduced, has been found to Santa Fe bark, 

 possess the febrifuge power by able physicians. It is gray on 

 the outside, red within, thick, little convoluted, with an as- 

 tringent and slightly bitter taste. Its infusion is much red- 

 der than that of the yellow bark. Tried in the same manner 

 it produced the following effects. 



With the solution of isinglass it gives a very copious red- r * .• -*u 



1- in • • rm • /*» . Its aCtiOU With 



dish nocculeut precipitate. Tins effect, which has never yet reagents. 

 been mentioned by any person to rny knowledge, is worthy 

 of remark. 



It occasioned no change in solution of emetic tartar, in 

 which it differs from the yellow bark. 



It throws down a nne deep green precipitate from solution 

 -of sulphate of iron; perceptibly reddens tincture of 

 litmus; is precipitated by oxalate of ammonia, but the 

 oxalate of lime it thus yields is much less than that from 

 the yellow bark. 



It precipitates acetate of lead and sulphate of copper of a 

 reddish brown. 



The principle which precipitates emetic tartar appears to r ts diftVene* 



be wanting in this bark: and a farther proof of its differ- from yellow' 



ing in some respects from the yellow bark is, that their infu- h " uk ' 



sions on mixture become turbid. 



The decocthm of this species produced the same effects ^ 

 • i .... Decoction, 



with reagents as its infusion : but it is observable, that it does 



not grow turbid on cooling. 



Spec. 



