CINCHONA; Jesuits' or Peruvian Bark.
By whom the important properties of the va. rions species of this genus was first made known to Europeans is unrecorded. The na tive Peruvians attached no febrifugal import ance to the bark. Its introduction to Europe took place through the Spaniards in the year 1640. Little was known of the tree producing this substance till the voyage of La Conda mine, who, in 1738, first printed a detailed account of Quinquina, as it was tt.en called.
The manner of collecting the Cinchona bark of commerce is thus described:—In the month of April the preparations for an expe dition commence; and in Maythe people start for the forest, whence the last green bales are transmitted home in November. They fell the trees close to the root, sparing those trunks which appear too young, as, till they have attained maturity, the bark is of no value. The next process is to divide the stems into pieces of uniform length, rejecting only the very smallest branches. The bark is then cut lengthwise, so as to remove the rind without injuring the wood or severing any of the fibres. In a few days the bark is taken off in strips as broad as possible. In the market the value of the bark depends on the celerity with which it is dried. In the dense forests it is impossible to perform this opera tion properly, and therefore the bundles of green bark are dispatched with all speed to the nearest inhabited place, where the person appointed to take charge of them is stationed. They are laid in a spot exposed to the fall action of the sun, and the greatest care is re quisite to protect them from the wet.
Cinchona barks, in England, are classed under three heads— pale, yellow, and red barks. Of each there are several varieties.
Of the Pale Barks, three varieties are known in English commerce :-1, Crown or Loxa Bark, 2, Gray, Silver, or Huanuco Bark ; 3, Ash Bark. These are always quilled, and never in flat pieces. The powder, which gives the name, varies from gray to fawn colour. The Crown Bark occurs in pieces from 6 to 14 inches long, the quills varying in diameter from the fourth or even smaller part of an inch to nearly half an inch. The colour of the exterior is marked dark gray, in some specimens verging to brown. The odour resembles that of tan. The taste at first is slightly astringent, and faintly acid ; after wards very astringent, somewhat bitter, but not acrid. The Gray and Ash Barks differ from the Crown chiefly in tint.
' The Yellow Barks also present three varie ties. The variety best known in England occurs in two forms—quills and flat pieces ; the quills were formerly most prized, but all well - informed persons now prefer the flat pieces as much richer in quinia. The exter nal surface is generally grayish brown, in clining to blackish, yellow, or whitish, accord ing to the kind of lichen by which it is beset. The flat Yellow Bark, or that in splints, occurs either with the epidermis or divested of it.
The Bed Bark, of which one kind only is known in English trade, was not much used in Europe till 1779. It occurs in quills and flat pieces, most frequently in the latter form.
The various forms of Cinchona Bark are justly considered the most valuable tonic and febrifugal medicines we possess ; and the commerce in them has thereby become im• portant.