Rensselaer Union, Volume 7, Number 11, Rensselaer, Jasper County, 3 December 1874 — Tea Adulterations. [ARTICLE]

Tea Adulterations.

One of the usual ways’of adulterating tea is by the admixture of leaves other than those of the tea-plant. For the detection of these foreign leaves but little aid can be given by chemistry, and it is best to study their botanical and microscopical characters. Prof. Alfred H. Allen gives,, in the Chemical News, the following method for detecting adulterationsof this kind: “ Some of the sample to be examined,” says he, “is to be put in hot water, and, when the leaves have unfolded, they are spread out on a glass plate and held up to the light, when the venation, serration, etc., are readily observed The primary venation or the t.ea-leaf forms a series of well-defined hoops, which are not met with in most leaves used as adulterants. Tlie serrations are not mere sawed, teeth on the margin of the legs, but actual hooks. The serration stops short, somewhat abruptly, at some distance above tlie base. TheAs : sam tea-leaf is sometimes bi-serrate. At the apex of the tea-leaf there is a distinct notch instead of a point. If we examine the under surface with a microscope after the separation of the cuticle the peculiar and characteristic 1 space between the two cells of the stomata is readily perceived. The long, unicellular hairs of the tea-leaf are also peculiar. The employment of caustic potash is desirable in observing these characters. In the sloe-leaf the serratures are direct ineisions, numerous, often irregular, and extending,down to tlie base. There are no spines. ihe hairs are shorter and coarser than those of the tea-leaf, and are marked in a peculiar manner. The elder-leaf is more pointed than that of the tea-plant, and the lobes are unequal at the base. ihe serratures are direct incisions.' The midriff has hairs on it, and on the leaf itself there are several kinds of hairs, notably a short, spinous, striated hair, which occurs on the upper surface. The serratures of the willowleaf much resemble those of tea, but the cell-walls of both the upper and under epidermis differ from those of the tealeaf in not being sinuous, and there are long, coarse, striated hairs. When perfect,'the elongated form of the willowleaf sufficiently distinguishes it from tea, and tlie venation is also entirely difterent., “The chief foreign leaves added by the Chinese are those of Chloranthus incOnspicuus and of Camellia susanqua, the latter of which presents A close resemblance to the tea-plant.” —A high-school pupil in a cross-town car recited her geometry lesson to a fel-low-girl, recently, as follows: “If the angles at the base of an isosceles triangle are equal to the square ot the hypotlienuse of, a right-angle cone, then the rectangle of the diameter of-a circle is equal to the square of the —ah —to the—ah —is equal to the —ah —to the square—to the—ah—oh, bother! Gimme that book! I wish pa ’ud let me take dancing lessons instead of these horrible squares, and angles, and bypothenuses.”— Chicago Journal.