CHEMICAL AND MICEOSCOPICAL INVESTIGATIONS. 
large, thick piece of each sort was chosen, and carefully divided into two portions of equal weight, one oi 
the inner, the other of the outer bark. Of each of these, 1000 grains were then taken and subjected to 
analysis : — 
No. 1. — C. succirtjbra (Pavon). 
Thickness of bark, average ^ inch. 
Outside . 
Tr) side 
* Quinine, cryst. as sulphate . 
3-36 
Do. cryst. as oxalate . 
2-24 
* Quinine, cryst. as oxalate 
. 0-50 
Do. uncryst. 
2-20 
Do. uncryst. 
. 1-90 
7-80 
2-40 
Cinchonidine, hydriodate . 
0-70 
Cinchonidine, hydriodate 
. 1-20 
cryst. from ether . 
1-20 
Cinchonine 
. 0-56 
1-90 
Cinchonicine 
. 0T3 
Cinchonine 
. 0-76 
Cinchonicine 
. 0-20 
4-29 
40-66 
No. 2.- 
-Spurious Eed Bark. 
Thickness, f inch ; inside especially woody. 
Inside . 
Outside . 
Cinchonidine . 
. 0-50 
*Sulph. Cinchonidine . 
. 0-60 
Cinchonine 
. 0-27 
Cinchonine 
. 0-30 
0-77 
0-90 
No. 3.- 
-C. Almaguerensis. 
Approaches in appearance 
to Eed bark, with leaves like C, Pitayensis. Thickness, 
if to f- inch, 
Inside . 
Outside . 
Oxalate of Quinine . 
. 0-40 
Oxalate of Quinine . 
. 1-00 
Quinidine, with trace of Cincho- 
Cinchonidine, and trace of Quini- 
nidine . 
. 0-68 
dine .... 
. 0-60 
Cinchonine 
. 0-35 
Cinchonine 
. 0-25 
Cinchonicine 
. 0-05 
Cinchonicine 
. 0-75 
1-48 2*60 
No. 4. — C. Palton. 
Saffron-coloured bark, very fibrous internally. Thickness, f inch. 
Inside . 
Sulph. Quinine . . 0*85 
Do. uncryst. . . . 0*47 
1*32 
Cinchonicine . . . .0*04 
1-36 
Outside . 
Quinine, sulph. . . 1*83 
Do. uncryst. . . . 0*80 
2*63 
Cinchonicine . . . .0*04 
2-67 
No. 5. — C. lancieolia. Var. 7. 
Great contrast between the fibrous inner bark and the cellular envelope. Thickness, inch. 
Inside . 
Quinine, sulphate 
Cinchonidine . 
Cinchonicine 
Outside . 
0-60 
Quinine, sulphate 
. 1-80 
0-40 
Cinchonidine . 
. 0-50 
0-15 
Cinchonicine 
. 0-15 
1-15 
2-45 
* In order to secure minute accuracy, the weight of the sulphuric or of the oxalic acid should be deducted from the salts in 
combination (as the reader will find in my Table, p. 1 7) . Practically , I find more instruction from the statement of results as obtained. 
