24 
DISTINCTIVE 
CHARACTERS OF CALISAYA BARK. 
pond to the fissures in the part removed. In contradistinc- 
tion to the preceding characters, ever}^ bark of which the cor- 
tical portion is shining, not rugged, not marked with nume- 
rous transverse fissures, is not true Calisaya, and ought to be 
considered unfit for the manufacture of sulphate of quinia. By 
this mode of distinction, the younger portions of the barks 
which I have described under the names orange yellow^ ( Q 
jauae orange ^) or light Calisaya (Calisaya leger,) the 
Columbia bark ( Quinquina de Columbie,) the white 
bark of Loxa (Q, blanc de Loxa,J Carthagena bark (Q. 
CarthageneJ and Cusco bark ( Q. de Cusco,) will be excluded. 
It is very difficult to indicate in writing, the differences 
which distinguish the young Calisaya with the epidermis 
from Loxa and Lima barks, and from the red bark destitute 
of warts. The latter, however, is easily recognised by the 
marked red colour of its liber, and it commands so high a 
price, as to induce little fear that it may be substituted for 
Calisaya. As regards the two first, they are recognised by 
their epidermis, which is more uniform and less deeply cleft, 
and by the greater degree of adhesion between this portion 
and the liber, which is less fibrous, more compact, with the 
fracture often short and resinous. Their taste is both astrin- 
gent and bitter, while the Calisaya has always an extremely 
fibrous fracture and a very bitter taste, with little astringency. 
Finally the test, by the sulphate of soda which I have pointed 
out, can allow of little doubt. This test consists in coarsely 
pulverizing a small quantity of the bark, triturating the powder 
in a porcelain mortar with water so as to form a liquid pap, 
and then filtering. Upon adding a few crystals of purified 
sulphate of soda to the filtered liquid, an abundant white pre- 
cipitate is formed with the Calisaya bark, while no pale bark 
possesses this property. 
When the Calisaya bark is obtained from the large branches 
or trunk of the tree, the epidermis is thicker, even some- 
times as much as an inch in thickness. It is still more 
rugose and more deeply cracked, but the furrows do not 
penetrate to the liber, which no longer exhibits the circular 
