quicker than unprepared cigars of equal strength and quality. They lose much of their fragrance by age.
Cigars, Stramo′′nium. Syn. Datu′ra cigars; Cigarræ stramo′′nii, L. From the leaves of Datura stramonium, or preferably those of the eastern species, Datura tatula. See Asthma, Datura.
CINCHONA BARKS. Syn. Cinchonæ cortex; Peruvian bark; Jesuit’s bark. The native names are quinquino and quina, quina. Of the nearly forty different known species of cinchona trees, the barks of about a third are employed, some either directly in medicine, but by far the larger number as sources of quinine and the other cinchona alkaloids. The original habitat of the genus Cinchona is the Andes, where it is found at a height of between 3000 and 12,000 feet above the sea, growing mostly in patches, distributed amongst the palms, plantains, and other tropical trees that form the vast forests, for the most part clothing the eastern slopes of the Cordilleras, and extending from 10° north to about 19° south latitude. In this district there is always an abundance of moisture and a mean temperature of about 62°. In 1853 the Dutch government introduced the cinchona into Java, and in 1861 the East Indian government, following their example, introduced it into British India, where it is now acclimatised, large plantations of it growing on the Neilgherries and in the valleys of the Himalayas. The cinchona is now also successfully cultivated in Ceylon and Jamaica.
The method followed in the collection of the bark by the Peruvians is a very wasteful and destructive one, and consists either in stripping the bark from the trees when they have attained a sufficient age, or in felling the tree a little above the roots. If the latter method be adopted, the roots give out a growth of suckers, which yield a good bark. The bark is never removed during the rainy season.
Previous to being stripped off, the bark is sometimes cleaned with a brush, and then peeled off in pieces varying from 15 to 18 inches long, and from 4 or 5 in width. The thinnest pieces, which are derived from the branches or the trunks of small trees, are dried in the sun, and thus acquire the well-known quill-like form. The larger trunks yield the flat specimens, which are submitted to a kind of pressure as they are being dried. The inferior specimens being rejected, the dried barks (mostly of the same kind) are sewed in canvas, and thus conveyed to the nearest depôt, from whence, previous to being shipped, they are enclosed in another envelope of fresh hide, the package being then known under the name of a seron.
Structure of Cinchona Barks. A few general observations on the structure of the bark of cinchona will be appropriate here. The epidermis is only found on the youngest bark, before it has attained sufficient age for medicinal use; it is then replaced by the corky layer. In most species this cracks, and is easily separable, but in some it is firmly attached to the internal layers. These are composed of the middle layer of the bark or mesophlæum, formed of parenchyma, and the innermost layer endophlæum, or liber. The middle layer disappears in some barks, which are thus wholly composed of liber. This is a means of distinguishing them. The liber is traversed by medullary rays, which project into the mesophlæum. It is, therefore, composed of woody fibres (prosenchyma) and soft parenchyma.
The arrangement of the woody fibres, their colour, size, and shape, give a special character to the cinchona barks.
As compared with other barks, the fibres of the liber are shorter and more loosely arranged, being for the most part separate or united into very short bundles. The fibres, therefore, are easily isolated; they are spindle-shaped, sub-quadrangular, rarely exceeding 1-10th of an inch in length, usually straight, and are very brittle, the cavity of the cell of which each is composed being reduced by secondary deposits to a fine canaliculus. This short and loose fibrous structure is not found in other barks.
In some cinchona bark a system of lactiferous vessels is found between the liber and mesophlæum.[247]
[247] Royle.