Jalap.—This drug is obtained from the dried tubers or root-stock of Ipomœa Jalapa or Convolvulus Jalapa, a perennial plant, native of America. Some suppose it takes its specific name from Xalapa, in Mexico, whence we chiefly import it. It grows in the woods near Chicanquiaco, at an altitude of 6,000 feet above the level of the sea. Large quantities might be gathered and exported in Jamaica. The root is of a roundish tuberous form, black externally, and of a deep, yellowish grey within, and varies in size from that of a walnut to that of a moderate sized turnip. It contains a resin in which its active properties reside. It is brought to this country in thin transverse slices, and the amount entered for home consumption is about 45,000 lbs. a year. It is imported in bales, from Vera Cruz direct, or indirectly by way of New York, and other places.
Two sorts of jalap root occur in commerce. The one which was first introduced into the market, and which is even at the present day most frequently met with, is obtained from the Ipomœa Schiedeana of Zuccarini, a plant growing on the eastern declivity of the Mexican Andes, and discovered by Von Schiedes. The root, as met with in commerce, consists of pieces varying from the size of a nut to that of the fist, sometimes whole, sometimes cut into disks, and at other times divided into two or three portions. The external surface is of a more or less dark gray brown color, corrugated and rough. It is very hard, presents a shining resinous even surface when broken, and is difficult to reduce to powder. The powder is of a brownish color, has a faint peculiar odor and irritant taste.
The second quality, which was introduced into commerce is great quantities a few years ago, by the name of stalk jalap, is now more scarce, and obtained from the Ipomœa orazabensis of Pelletan, a plant growing without cultivation in the neighbourhood of the Mexican town of Orizaba. The root, as met with in the trade, consists of pieces varying from one to three inches in length, and 1½ to two inches in diameter. They are of a higher color than the first-named root, and of decidedly fibrous structure. The chief constituents of both varieties is a peculiar resin, of which they contain about 10 per cent.
Scammony.—The root of Convolvulus Scammonia, another plant of the same family, affords, when cut, a gummy resinous exudation or milky juice, which soon concretes and forms scammony. The plant grows abundantly in Greece, the Grecian Islands, and various parts of the Levant. It is imported from Aleppo in drums, weighing from 75 to 125 lbs. each, and from Smyrna in compact cakes like wax packed in chests. In 1839, the quantity on which duty (2s. 6d. per lb.) was paid amounted to 8,581 lbs. The duty received for scammony, in 1842, was £607. A spurious kind is prepared from Calystegia (Convolvulus) sepium, a native of Australia, and several plants of the Asclepiadacæ order.
Dr. Russell ("Med. Obs. and Inqui.") thus describes the mode of procuring scammony:—
Having cleared away the earth from the upper part of the root, the peasants cut off the top in an oblique direction, about two inches below where the stalks spring from it. Under the most depending part of the slope they affix a shell, or some other convenient receptacle, into which the milky juice flows. It is then left about twelve hours, which time is sufficient for the drawing off of the whole juice; this, however, is in small quantities, each root affording but a few drachms. This milky juice from the several roots is put together, often into the leg of an old boot, for want of some more proper vessel, when in a little time it grows hard, and is the genuine scammony. Various substances are often added to scammony while yet soft. Those with which it is most usually adulterated are wheat flour, ashes, or fine sand and chalk.
Liquorice.—The plant which yields the liquorice root of commerce is Glycirrhiza glabra or Liquiritia officinalis. It is a native of Italy and the southern parts of Europe, but has been occasionally cultivated with success in Britain, especially at Pontefract, in Yorkshire, and at Mitcham, in Surrey. The plant is a perennial, with pale blue flowers. It grows well in a deep, light, sandy loam, and is readily increased by slips from the roots with eyes. The root, which is the only valuable part, is long, slender, fibrous, of a yellow color, and when grown in England is fit for use at the end of three years. The sweet, subacid, mucilaginous juice is much esteemed as a pectoral. It owes its sweetness to a peculiar principle called glycrin or glycirrhiza, which appears also to be present in the root and leaves of other papilionaceous plants, as G. echinata and glandulifera, Trifoliwm alpinum, and the wild liquorice of the West Indies, Abrus precatorius, a pretty climber.
The greatest portion of our supplies of the extract, which amount to 7,000 or 8,000 cwts. a year, are obtained from Spain and Sicily. The juice, obtained by crushing the roots in a mill, and subjecting them to the press, is slowly boiled, till it becomes of a proper consistency, when it is formed into rolls of a considerable thickness, which are usually covered with bay leaves. It is afterwards usually re-dissolved, purified, and, when formed into small quills, is known as refined liquorice.
In 1839, 1,166 tons of liquorice paste were exported from Naples, valued at £45 per ton. Mr. Poole, in his Statistics of Commerce, states that the consumption of liquorice root and paste in this country averages 500 tons per annum. 110 cwt. of the juice and 100 cwt. of the root are annually brought into Hull from the continent.
Matico—the Peruvian styptic, a powerful vegetable astringent, was first made known to the medical profession of England by Dr. Jeffreys, of Liverpool, in the Lancet, as far back as January 5th, 1839. A paper on its history and power was published in May, 1843, in the "Transactions of the Provincial Medical and Surgical Association," vol. 10. It is stated to be the Piper angustifolium of Ruiz and Parsons. Dr. Martin believes it to be a species of Phlomis. The leaves are covered with a fine hair.