Cinchona.—­Peruvian or Jesuit’s Bark—­One of the most valuable and powerful astringents and tonics used in medicine, is the produce of several species of cinchona, natives of the Andes, from 11 north latitude to 20 south latitude, at elevations varying from 1,200 to 10,000 feet above the level of the sea, and in a dry rocky soil.  There are at least twelve trees which are supposed to furnish the barks of commerce, and great obscurity prevails as to the species whence the various kinds of cinchona bark are derived.  The names of yellow, red, and pale bark have been very vaguely applied, and are by no means well defined.  Dr. Lindley mentions twenty-six varieties; of which twenty-one are well known.  The barks are met with either in thick, large, flat pieces, or in thinner pieces, which curl inwards during drying, and are called quilled.

Quinine is one of the most important of the vegetable alkaline bitters.  It was first discovered by Vauquelin, in 1811, and its preparation on a large scale pointed out by Pelletier and Caventon in 1820.  It is obtained by boiling the yellow bark (Cinchona) in water and sulphuric acid, and then treating it with lime and alcohol, when the quinine is precipitated in the form of a white powder.  Upwards of 120,000 ounces are made annually in Paris.

Cinchona, or the Peruvian bark, was gathered to the amount of two million dollars in one year recently, and the demand is constantly increasing.

Peruvian bark is cut in the eastern Provinces of Bolivia, skirting the river Paraguay, and now conveyed an immense distance by mules over a mountainous region to El Puerto, the only port of Bolivia on the Pacific.  It is thence brought by Cape Horn to the cities of the United States and Europe.  Now that Government has been successful in opening the South American rivers, this important article of commerce will be furnished in market by the Paraguay and La Plata rivers, at a much reduced price.

A species of bark from Colombia, known as Malambo or Matias bark, has been frequently administered by Dr. Alexander Ure as a substitute for cinchona with good effect.  It offers the useful combination of a tonic and aromatic.  It is supposed to be the produce of a species of Drimys.  It is stated that in New Granada, and other districts of Central America, where the tree is indigenous, incisions are made in the bark, and there exudes an aromatic oil which sinks in water.

Cinchona bark contains two alkaloids, cinchonia and quina, to which its active properties are due; the former is best obtained from gray bark, the latter from yellow bark.  In combination with these there exists an acid called kinic acid.

The imports of cinchona bark to this country are from 225,000 to 556,000 lbs. annually, and about 120,000 lbs. are retained for home consumption.  It comes over in chests and serons, or ox-hides, varying from 90 to 200 lbs.  We imported from France, in 1850, 489 cwt. of Peruvian bark, of the value of L6,840; and in 1851, 1,128 cwt., of the value of L15,787; also the following quantities of sulphate of quinine, on which there is a duty of 6d. and 3-10ths per ounce.