CINCHONA CEM. 



and attains a height of thirty or forty feet. This 

 species, from being the first introduced into Europe 

 by Condamine, has been called, by Hnmboldt and 

 Bonpland, Cinchona Condaminc. The bark of this 

 species generally occurs, in commerce, in the form of 

 small tubes or quills, which are covered with a rough 

 epidermis on which numerous lichens grow. These 

 lichens are of importance, as indicating the peculiar 

 quality of the bark. The bark, bearing lichens of 

 the genera Grapkis, Lccanora and Usnea, is esteemed 

 good. These lichens ought to be scraped off' before 

 the bark is powdered tor use. There are several 

 varieties of pale bark, imported from Loxa and Gua- 

 naco, of which the chief are, the quilled bark of Loxa, 

 or Cascarilla do Loxa, the grey bark of Loxa, the 

 bark of Lima, and the Havannah bark. 



Cincliona cordifolia, yellow bark, is a handsome 

 tree, which grows abundantly on the mountains of 

 Loxa and Suiita Fe, in the fourth degree of north, 

 latitude, at an elevation of six or seven thousand 

 feet above the level of the sea. The bark of this 

 species is thicker, less quilled, and more woody and 

 fibrous than the pale bark. It is frequently com- 

 pletely devoid of epidermis, and more especially 

 when not quilled. There are two varieties of the 

 bark in commerce, the Calisaya or royal yellow bark, 

 and the orange yellow bark. The yellow bark is less 

 astringent and more bitter than the pale bark. 



Cinchona oblongi/oha, red bark, grows in new Gre- 

 nada, near Maraquita, in the fifth degree of north 

 latitude. There are two varieties of this bark, the 

 smooth red bark, or the quina roxa, or colnada of 

 commerce, and the warty red bark of Santa Fe de 

 Bogota, which is considered by some authors as the 

 produce of Cincliona magnifoKa. 



Cinchona or Peruvian bark has been long known 

 as a febrifuge, and seems to have been employed as 

 such in Peru at the time of the Spanish conquest; 

 but no accurate accounts are given of the time when 

 it was first used. Among the many fables which 

 have been circulated in regard to this bark, it has 

 been stated that its efficacy in fever was accidentally 

 discovered by a person afflicted with ague, who drank 

 the water of a stream into which a cinchona tree had 

 fallen, and to which it had impaited its virtues. 

 The Jesuits in early times used to distinguish the 

 different kinds of trees by chewing their bark, and it 

 is said that they were attracted by the peculiar bit- 

 terness of the cinchona, and employed it in the cure 

 of disease. On this account it long retained the 

 name of Jesuits' bark. The name cinchona is derived 

 from the circumstance of a cure having been effected 

 by means of the bark, in the case of the Countess of 

 Cinchon, lady of a Count who acted as Spanish 

 viceroy in Lima, from 1629 to l.'i.'Ji). 



Cinchona bark, on its first introduction into Europe, 

 met with great opposition from medical men, who 

 were prejudiced against it chiefly on account of its 

 novelty. Its failure too in the cure of many diseases, 

 for which it was at first extolled as an infallible 

 remedy, would lead physicians to doubt its efficacy 

 in any disease whatever. After careful observation 

 und repeated trials, the powers of cinchona were at 

 length fully ascertained, and its reputation as a re- 

 medy of great importance was completely established. 

 It soon became an important article of commerce, 

 and was admitted into the materia medica. It is now 

 extensively used all over the world, and large quan- 

 tities are annually imported bto Europe from Guay- 

 NAT. HIST. VOL. II. 



aquil, Lima, Loxa, Buenos Ayres, Carthagena, Santa 

 Martha, and other parts of South America. 



The value of Peruvian bark has frequently led to its 

 Adulteration ; a considerable degree of care and atten- 

 tion are required in its selection. By inattention to 

 this, and the consequent employment of spurious barks, 

 the true article has often been brought into disrepute. 

 Good bark is dense, heavy and dry, not musty or 

 spoiled by moisture, and a decoction of it is red 

 while warm, and becomes paler on cooling. Barks, 

 which are simply internally bitter or astringent, or 

 merely mucilaginous, whose surface is smooth or of a 

 dark colour, whose fracture is fibrous, and internal 

 colour white or grey, are bad, and ought to be rejected. 

 The means of distinguishing good bark were of 

 reater importance formerly, when the bark was con- 

 stantly used in substance, than now-a-days, since the 

 discovery of the active principles of the bark. For 

 this important discovery we are principally indebted 

 to the labours of French chemists, although Dr. 

 Duncan, formerly professor of materia medica in the 

 University of Edinburgh, was undoubtedly the first 

 who suggested the existence of a peculiar principle 

 in bark. By the researches of MM. Pelletier and 

 Caveutou, it has been ascertained that there exist in 

 cinchona two alkaloids, to which the names of cin- 

 chonia and quinia have been applied, and which 

 possess in a concentrated degree, the properties of 

 the bark itself. These alkaline substances exist in 

 combination with a peculiar acid called kinic acid, 

 and their quantity varies in the different kinds of 

 bark. According therefore as we wish to procure 

 the one or the other, we must select a particular sort 

 of bark for the purpose. Pale bark yields chiefly 

 cinchonia, and the yellow furnishes quinia, with a 

 small proportion of cinchonia, while in the red bark 

 both these substances exist in nearly equal propor- 

 tions. It will be seen that thus the barks are not 

 only distinguished by their colour, and the other 

 characters formerly noticed, but also by their che- 

 mical constituents. Besides these alkaloids, bark 

 consists of kinate of lime, fatty matter, red colouring- 

 matter, tannin, yellow colouring matter, gum, starch, 

 and lignin, or woody fibre. 



By a particular chemical process we are able to 

 separate the active principles of the bark from all the 

 impurities which exist in it, and in this way obtain 

 most valuable articles of materia medica. To procure 

 cinchonia, the pale bark is powdered and boiled in 

 water, along with a quantity of sulphuric acid or oil 

 of vitriol. This process is repeated several times 

 with fresh portions of acidulated water, until all the 

 soluble matter is extracted. The decoctions thus 

 made are evaporated and mixed with newly-slaked 

 lime, which forms an insoluble sulphate of lime, and 

 carries down the cinchonia as a precipitate along with 

 it. On adding boiling alcohol to this precipitate 

 after it is dried, the cinchonia is dissolved, while the 

 sulphate of lime is left ; and the former is afterwards 

 procured in a crystalline state by evaporation, and 

 may be purified by the addition of animal charcoal, 

 and a second solution in alcohol. When thus ob- 

 tained in a pure state, cinchonia is a white, crystalline 

 salt, having a bitter taste, nearly insoluble in cold 

 water, and requiring 2,500 times its weight of boiling 

 water for solution. Owing to this insolubility it does 

 not act powerfully on the animal frame, unless in com- 

 bination with some acid, such as the sulphuric. The 

 kinic acid, w : ith which cinchonia is combined in the 

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