110 6X VAV10US SPECIES OF CINCHONA. 



Spec. 3. Gray Lark, called super fine. 

 Gray bark. The infusion of this species ib nearly colourless. lis taste 



is bitter ami astringent. 

 its action with It forms a very copious white precipitate with isinglass, a 

 i»agent.% rfcc j w ^jj j n f u <ji on f tan, a copious and white with emetic 



tartar, ami a very fine emerald green with sulphate of iron. 



It produces no change in infusion of yellow b.irk. 



Spj'C 4. Cinnamon gray bark. 



Cinnamon The infusion is of a deep red, and has a bitter astringent 



& ra r- taste. 



its action with It precipitates solution of isinglass of a brown fawn colour, 



reagents. gives a green colour with sulphate of iron, but does not pre- 



cipitate emetic tartar. 



It occasions no change in the infusion of the gray bark, 

 but it produces a brown precipitate with that of the yellow 

 bark, and does not precipitate the infusion of tan. 



Gelatine and These vegetable infusions, after having precipitated each 



tanansed arm- otner as completely as possible, act no longer on emetic tar- 



mony precipi- . . " . 



tated by differ- tar: whence it follows, that the principle in the inlusion of 

 pnncip es. y P ]j ow ^ ai .^ w hich precipitates this salt combines with some- 

 thing in the infusion of cinnamon gray bark and tan. But 

 these infusions, thus precipitated, still throw down an abun- 

 dant precipitate from solution of isinglass, whence it follows, 

 that these two substances are precipitated by different prin- 

 ciples. 



Precipitate The precipitate formed by mixing the infusions of the 1st 



from spec. 1 am ] ^ S p ec j es d r j e s easily, swells up when heated, gives out 

 and 4» ' ' 



a smoke devoid of acrimony, and having some analogy to 



that of animal substances, and leaves a light spongy coal. 

 Spec. 5. Ilcd bark, called pit ton in the shops. 



Red bark. ^ n ^ s ]S erroneously, named, for the true pitton bark has dif- 



ferent characters, as will be seen farther on. 



Its infusion has a light orange red colour, and an astringent 

 bitter taste. 

 Its action with ^ f° rnis a copious reddish precipitate with isinglass, yel» 

 «gen lowisb white with emetic tartar, brown with the infusion of 



the 



