CINCHONA 585 borazo and the neighborhood. C. nitida is also indicated by Weddell as a source of this variety. The pale or gray barks are referred to C. Condaminea and C. micrantha by the " United States Dispensatory," but other species (C. ovata, scrobiculata, macrocalyx, and uritu- singd) probably contribute to the supply. The Carthagena barks are probably derived partly from some of the same species with the kinds just mentioned, and partly from C. cordifolia, C. lancifolia, and C. Pitayensis. Some of them are of very good quality, and are exten- sively used for the extraction of the alkaloids. The "false" barks are derived from inferior species of cinchona and allied genera. The cinchonas appear to thrive best in regions subject neither to extreme heat nor extreme cold, where a somewhat even temperature pre- vails throughout the year, and where they are partially protected by their neighbors from the direct rays of the sun. These conditions are fulfilled upon the slopes of the Andes between Cinchona calisaya. lat. 19 S. and 10 N. For more than a cen- tury after Peruvian bark came into use, it was supposed to exist only in Loxa in the ancient kingdom of Quito, and in a few neighboring localities; but in the year 1753 it was dis- covered in various other places of a correspond- ing elevation with Loxa above the sea. Little advantage, however, resulted from this; but some 20 years later, under the patronage of the Spanish government, researches were made in New Granada, which resulted in the dis- covery of several species of cinchona. At a subsequent period supplies of the bark were obtained from other sources, which are now shipped from many of the South American ports, including some ports in the Caribbean sea. Considerable care and experience are necessary in collecting the barks, to select those most valuable, and to know the proper age at which a branch should be decorticated. The bark is collected between May and No- vember. The tree is usually cut down and then stripped, which is the most economical plan, as fresh shoots spring up from the old roots. But the Indians, to save themselves the trouble, often strip the bark entirely from the tree while it is standing, thus destroying it a! 7 together. Owing to the reckless manner in which the bark has been collected, and the en- tire absence of any efficient protection to the forests on the part of the government or pro- vision for the cultivation of the trees in planta- tions, the danger of a serious diminution in the supply of this valuable drug is by no means a remote one. For many years all the large trees of valuable species have disappeared from easily accessible regions. Dr. Weddell in 1847, in order to see the C. calisaya in its full vigor, was obliged to make long journeys on foot through the forests, and endure the hardships and privations of the poor cascarilleros or bark collectors. The Dutch and British govern- ments have made successful attempts to intro- duce the cinchona into their East India pos- sessions, in Java, and various parts of Hindostan, where the mountainous regions furnish the necessary temperature and moisture for their growth. It has been found that the yield of some species of cinchona in alkaloids may be much increased by covering the bark with moss, and also that a longitudinal strip of bark may each year be taken from a tree without destroying it ; the decorticated portion renew- ing, if "mossed," its former covering, at least as rich in alkaloids as before. Bark from the English plantations has already been introduced into commerce. More or less successful at- tempts at cinchona culture have been made in Jamaica, the isle of Reunion, Guadeloupe, Brazil, the Azores, and Algeria. It is possible that situations may be found within the limits of the United States suitable for the culture of the cinchonas. The division of the bark into flat and quilled is determined simply by the part of the tree from which it is taken, whether trunk or branches, and the method of drying it, whether under pressure or allowed to roll up. The medicinal value of Peruvian bark de- pends upon the alkaloids which it contains. These are quinia, cinchonia, quinidia, cincho- nidia, quinicia, and cinchonicia. Another al- kaloid called cincine is found in small quantity in some of the inferior varieties. It is probable that the three latter alkaloids are artificial derivatives from the former. In addition to these, the bark contains in varying proportions gum, starch, lignine oil, yellow coloring matter, insoluble red coloring matter, soluble red coloring matter or cincho tannic acid, kinic and kinovic acids. The various alkaloids are produced in the bark itself, and that probably by a reaction between the ammonia, which (according to De Vry) is everywhere contained in the plant, and the cincho-tannic acid. The general condition of the alkaloids is that of being more pure and easily separated from adventitious substances in the bark of the branches, somewhat less so in that of the
Page:The American Cyclopædia (1879) Volume IV.djvu/597
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