I.—PHÆNOGAMOUS OR FLOWERING PLANTS. (continued 6)

The tragacanth of Kurdistan and Persia shipped from Bagdad, which sometimes appears in the London drug sales under the incorrect name of Syrian Tragacanth, is in very fine and large pieces which are rather more translucent and ribbon-like than the selected tragacanth imported from Smyrna: in fact, the two varieties when seen in bulk are easily distinguishable.

The inferior kinds of tragacanth have more or less of colour, and are contaminated with bark, earth and other foreign substances. They used formerly to be much imported into Europe, and were frequently mentioned during the past centuries as black tragacanth.

Microscopic Structure—The transformation of the cells into tragacanth is usually not so complete, that every trace of the original tissue or its contents has disappeared. In the ordinary drug, the remains of cell-walls as well as starch granules may be seen, especially if thin slices are examined under oil or any other liquid not acting on the gum. Polarized light will then distinctly show the starch and the cell-walls. If a thin section is imbued with a solution of iodine in iodide of potassium and then moistened with concentrated sulphuric acid, the cell-walls will assume a blue colour as well as the starch.

Chemical Composition—When tragacanth is immersed in water it swells, and in the course of some hours disintegrates so that it can be diffused through the liquid. So great is its power of absorbing water that even with 50 times its weight, it forms a thick mucilage. If one part of tragacanth is shaken with 100 parts of water and the liquid filtered, a neutral solution may be obtained which yields an abundant precipitate with acetate of lead, and mixes clearly with a concentrated solution of ferric chloride or of borax,—in these respects differing from a solution of gum arabic. On the other hand, it agrees with the latter in that it is thrown down as a transparent jelly by alcohol, and rendered turbid by oxalate of ammonium. The residue on the filter is a slightly turbid, slimy, non-adhesive mucilage, which when dried forms a very coherent mass. It has received the name of Bassorin, Traganthin or Adraganthin, and agrees with the formula C₁₂H₂₀O₁₀.

Tragacanth is readily soluble in alkaline liquids, even in ammonia water and at the same time assumes a yellow colour; heated with ammonia in a sealed tube at 90° C. it blackens.

The drug loses by drying about 14 per cent. of water, which it absorbs again on exposure to the air. Pure flake tragacanth incinerated leaves 3 per cent. of ash.

Commerce—Tragacanth is shipped from Constantinople, Smyrna and the Persian Gulf. The annual export of the gum from Smyrna has been recently stated[714] to be 4,500 quintals, value 675,000 Austrian florins (£67,500); and the demand to be always increasing.

Uses—Though tragacanth is devoid of active properties, it is a very useful addition to many medicines. Diffused in water it acts as a demulcent, and is also convenient for the suspension of a heavy powder in a mixture. It is an important ingredient for imparting firmness to lozenges and pill-masses.

Adulteration—The fine quantities consisting of large distinct pieces are not liable to adulteration, but the small and the inferior kinds are often sophisticated. At Smyrna, tragacanth is mixed with gums termed respectively Mosul and Caramania Gum. The former appears to be simply very inferior tragacanth; the latter which is sometimes called in the London market Hog Gum Tragacanth or Bassora Gum,[715] is said to be the exudation of almond and plum trees. It occurs in nodular masses of a waxy lustre and dull brown hue, which immersed in water gradually swells into a voluminous white mass. To render this gum available for adulteration, the lumps are broken into small angular fragments, the size of which is adjusted to the sort of tragacanth with which they are to be mixed. As the Caramania Gum is somewhat dark, it is usual to whiten it by white lead, previous to mixing it with Small Leaf or Flake, or with the Vermicelli gum.

By careful examination the fraud is easily detected, angular fragments not being proper to any true tragacanth. The presence of lead may be readily proved by shaking suspected fragments for a moment with dilute nitric acid, which will dissolve any carbonate present, and afford a solution which may be tested by the ordinary reagents.

RADIX GLYCYRRHIZÆ.

Radix Liquiritiæ; Liquorice Root; F. Réglisse; G. Süssholz, Lakritzwurzel.

Botanical Origin—Glycyrrhiza glabra L., a plant which under several well marked varieties[716] is found over an immense extent of the warmer regions of Europe, spreading thence eastward into Central Asia. The root used in medicine is derived from two principal Varieties, namely:—

α. typica—Nearly glabrous, leaves glutinous beneath, divisions of the calyx linear-lanceolate often a little longer than the tube, corolla purplish blue, legume glabrous, 3-6 seeded. It is indigenous to Portugal, Spain, Southern Italy, Sicily, Greece, Crimea, the Caucasian Provinces and Northern Persia; and is cultivated in England, France and Germany.

γ. glandulifera (G. glandulifera W.K.)—Stems more or less pubescent or roughly glandular, leaves often glandular beneath, legume sparsely or densely echinate-glandular, many-seeded, or short and 2-3 seeded. It occurs in Hungary, Galicia, Central and Southern Russia, Crimea, Asia Minor, Armenia, Siberia, Persia, Turkestan and Afghanistan.

G. glabra L. has long, stout, perennial roots, and erect, herbaceous annual stems. In var. α., the plant throws out long stolons which run horizontally at some distance below the surface of the ground.

History—Theophrastus[717] in commenting on the taste of different roots (3rd cent. b.c.) instances the sweet Scythian root which grows in the neighbourhood of the lake Mæotis (Sea of Azov), and is good for asthma, dry cough and all pectoral diseases,—an allusion unquestionably to liquorice. Dioscorides,[718] who calls the plant γλυκιῤρίζη, notices its glutinous leaves and purplish flowers, but as he describes the pods to be in balls resembling those of the plane, and the roots to be sub-austere (ὑπόστρυϕνοι) as well as sweet, it is possible he had in view Glycyrrhiza echinata L. as well as G. glabra.

Roman writers, as Celsus and Scribonius Largus, mention liquorice as Radix dulcis. Pliny, who describes it as a native of Cilicia and Pontus, makes no allusion to it growing in Italy.

The cultivation of liquorice in Europe does not date from a very remote period, as we conclude from the absence of the name in early mediæval lists of plants. It is, for instance, not enumerated among the plants which Charlemagne ordered (a.d. 812) to be introduced from Italy into Central Europe;[719] nor among the herbs of the convent gardens as described by Walafridus Strabus,[720] abbot of Reichenau, lake of Constance, in the 9th century; nor yet in the copious list of herbs contained in the vocabulary of Alfric, archbishop of Canterbury in the 10th century.[721]

On the other hand, liquorice is described as being cultivated in Italy by Piero de’ Crescenzi[722] of Bologna, who lived in the 13th century. The cultivation of the plant in the north of England existed at the close of the 16th century, but how much earlier we have not been able to trace.

As a medicine the drug was well known in Germany in the 11th century, and an extensive cultivation of the plant was carried on near Bamberg, Bavaria, in the 16th century, so that in many of the numerous pharmaceutical tariffs of those times in Germany not only Glycyrrhizæ succus creticus, seu candiacus, seu venetus is quoted, but also expressly that of Bamberg.[723]

The word Liquiritia, whence is derived the English name Liquorice (Lycorys in the 13th century), is a corruption of Glycyrrhiza, as shown in the transitional mediæval form Gliquiricia. The Italian Regolizia, the German Lacrisse or Lakriz, the Welsh Lacris[724] and the French Réglisse (anciently Requelice or Recolice) have the same origin.

Cultivation, and habit of growth—The liquorice plant is cultivated in England at Mitcham and in Yorkshire, but not on a very extensive scale. The plants, which require a good deep soil, well enriched by manure, are set in rows, attain a height of 4 to 5 feet and produce flowers but not seeds. The root is dug up at the beginning of winter, when the plant is at least 3 or 4 years old. The latter has then a crown dividing into several aerial stems. Below the crown is a principal root about 6 inches in length, which divides into several (3 to 5) rather straight roots, running without much branching, though beset with slender wiry rootlets, to a depth of 3, 4 or more feet.[725] Besides these downward-running roots, the principal roots emit horizontal runners or stolons, which grow at some distance below the surface and attain a length of many feet. These runners are furnished with leaf buds and throw up stems in their second year.

Every portion of the subterraneous part of the plant is carefully saved; the roots proper are washed, trimmed, and assorted, and either sold fresh in their entire state, or cut into short lengths and dried, the cortical layer being sometimes first scraped off. The older runners distinguished at Mitcham as “hard,” are sorted out and sold separately; the young, called “soft,” are reserved for propagation.

In Calabria, the singular practice prevails of growing the liquorice among the wheat in the cornfields.

Description—Fresh liquorice (English) when washed is externally of a bright yellowish-brown. It is very flexible, easily cut with a knife, exhibiting a light yellow, juicy, internal substance which consists of a thick bark surrounding a woody column. Both bark and wood are extremely tough, readily tearing into long, fibrous strips. The root has a peculiar earthy odour, and a strong and characteristic sweet taste.

Dried liquorice root is supplied in commerce either with or without the thin brown coat In the latter state it is known as peeled or decorticated. The English root, of which the supply is very limited, is usually offered cut into pieces 3 or 4 inches long, and of the thickness of the little finger.

Spanish Liquorice Root, also known as Tortosa or Alicante Liquorice, is imported in bundles several feet in length, consisting of straight unpeeled roots and runners, varying in thickness from ¼ to 1 inch. The root is tolerably smooth or somewhat transversely cracked and longitudinally wrinkled; that from Tortosa is usually of a good external appearance, that from Alicante sometimes untrimmed, dirty, of very unequal size, showing frequently the knobby crowns of the root. Alicante liquorice root is sometimes shipped in bags or loose.

Russian Liquorice Root, which is much used in England, is we presume derived from G. glabra var. glandulifera. It is imported from Hamburg in large bales, and is met with both peeled and unpeeled. The pieces are 12 to 18 inches long, with a diameter of ¼ of an inch to 1 or even 2 inches. Sometimes very old roots, split down the centre and forming channelled pieces as much as 3½ inches wide at the crown end, are to be met with. This liquorice in addition to being sweet has a certain amount of bitterness.

Microscopic Structure—The root exhibits well-marked structural peculiarities. The corky layer is made up of the usual tabular cells; the primary cortical tissue of a few rows of cells. The chief portion of the bark consists of liber or endophlœum, and is built up for the most part of parenchymatous tissue accompanied by elongated fibres of two kinds, partly united into true liber-bundles and partly forming a kind of network, the smaller threads of which deviate considerably from the straight line. Solution of iodine imparts an orange hue to both kinds of bast-bundles, and well displays the structural features of the bark.

The woody column of the root exhibits three distinct forms of cell, namely ligneous cells (libriform) with oblique ends; parenchymatous, almost cubic cells; and large pitted vessels. In the Russian root, the size of all the cells is much more considerable than in the Spanish.

Chemical Composition—The root of liquorice contains, in addition to sugar and albuminous matter, a peculiar sweet substance named Glycyrrhizin, which is precipitated from a strong decoction upon addition of an acid or solution of cream of tartar, or neutral or basic acetate of lead. When washed with dilute alcohol and dried, it is an amorphous yellow powder, having a strong bitter-sweet taste and an acid reaction. It forms with hot water a solution which gelatinizes on cooling, does not reduce alkaline tartrate of copper, is not fermentable, and does not rotate the plane of polarization. From the analysis and experiments of Rösch, performed in the laboratory of Gorup-Besanez at Erlangen, in 1876, the formula C₁₆H₂₄O₆ was derived for glycyrrhizin. By boiling it with dilute hydrochloric or sulphuric acid it is resolved into a resinous amorphous bitter substance named Glycyrretin, and an uncrystallizable sugar having the characters of glucose. The formula of glycyrretin has not yet been settled. Weselsky and Benedikt, in 1876, showed that 65 per cent. of it may be obtained from glycyrrhizin. By melting glycyrretin with about 5 parts of caustic potash paraoxy-benzoïc acid is produced.

Alkalis easily dissolve glycyrrhizin with a brown colour and emission of a peculiar odour. In the root it perhaps exists combined with ammonia, inasmuch as the aqueous extract evolves that alkali when warmed with potash (Roussin, 1875). According to Sestini (1878) glycyrrhizin is present in the root combined with calcium; he obtained 6·3 per cent. of glycyrrhizin from the root previously dried at 110°. By exhausting glycyrrhizin with glacial acetic acid Habermann in 1876 succeeded in isolating almost colourless crystals having the sweet taste of the root. They yield, by boiling them with dilute acids, a yellow substance which would appear to agree with glycyrretin. The deep yellow walls of the vessels and prosenchymatous cells appear to be the chief seat of the glycyrrhizin.

The sugar of liquorice root has not yet been isolated; the aqueous infusion of the dried root separates protoxide of copper from an alkaline solution of cupric tartrate. Yet the sugar as extracted from the fresh root by cold water does not precipitate alkaline cupric tartrate at all in the cold, and not abundantly even on prolonged boiling.

Asparagin was obtained from the root by Robiquet (1809) and by Plisson (1827). Sestini (1878) isolated 2-4 parts of asparagin from 100 parts of the root dried at 110° C. Robiquet also found the root to contain malic acid. The presence of starch in abundance is shown by the microscope as well as by testing a decoction of the root with iodine. The outer bark of the root contains a small quantity of tannin.

Commerce—Liquorice root is imported into Great Britain from Germany, Russia and Spain, but there are no data for showing to what extent. France imported in 1872 no less than 4,348,789 kilogrammes (4282 tons), which was more than double the quantity imported the previous year.[726]

Liquorice root is much used in China, and is largely produced in some of the northern provinces. In 1870, 1,304 peculs were shipped from Ningpo,[727] and 7,147 pepuls in 1877 from Cheefu (one pecul = 133·33 lb. avdp.).

Uses—Liquorice root is employed for making extract of liquorice and in some other pharmaceutical preparations. The powdered root is used to impart stiffness to pill-masses and to prevent the adhesion of pills. Liquorice has a remarkable power of covering the flavour of nauseous medicines. As a domestic medicine, liquorice root is far more largely used on the Continent than in Great Britain.

SUCCUS GLYCYRRHIZÆ.

Succus Liquiritiæ, Extractum Glycyrrhizæ Italicum; Italian Extract of Liquorice, Spanish Liquorice, Spanish Juice; F. Jus ou Suc de Réglisse; G. Süssholzsaft, Lakriz.

Botanical Origin—Glycyrrhiza glabra L., see preceding article, p. 179.

History—Inspissated liquorice juice was known in the time of Dioscorides, and may be traced in the writings of Oribasius and Marcellus Empiricus in the latter half of the 4th century, and in those of Paulus Ægineta in the 7th. It appears to have been in common use in Europe during the middle ages. In a.d. 1264, “Liquorice” is charged in the Wardrobe Accounts of Henry III.;[728] and as the article cost 3d. per lb., or the same price as grains of paradise and one-third that of cinnamon, we are warranted in supposing the extract and not the mere root is intended. Again, in the Patent of Pontage granted by Edward I., a.d. 1305, to aid in repairing the London Bridge, permission is given to lay toll on various foreign commodities including Liquorice.[729] A political song written in 1436[730] makes mention of Liquorice as a production of Spain, but the plant is not named as an object of cultivation by Herrera, the author of a work on Spanish agriculture in 1513.

Saladinus,[731] who wrote about the middle of the 15th century, names it among the wares kept by the Italian apothecaries; and it is enumerated in a list of drugs of the city of Frankfort written about the year 1450.[732]

Dorsten,[733] in the first half of the 16th century, mentions the liquorice plant as abundant in many parts of Italy, and describes the method of making the Succus by crushing and boiling the fresh root. Mattioli[734] states that the juice made into pastilli was brought every year from Apulia, and especially from the neighbourhood of Monte Gargano. Extract of liquorice was made at Bamberg in Germany, where the plant is still largely cultivated, as early as 1560.[735]

Manufacture—This is conducted on a large scale in Spain, Southern France, Sicily, Calabria, Austria, Southern Russia (Astracan and Kasan), Greece (Patras) and Asia Minor (Sokia and Nazli, near Smyrna); but the extract with which England is supplied is almost exclusively the produce of Calabria, Sicily and Spain.

The process of manufacture varies only by reason of the amount of intelligence with which it is performed, and the greater or less perfection of the apparatus employed. As witnessed by one of us (H.) at Rossano in Calabria in May, 1872, it may be thus described from notes made at the time. The factory employs about 60 persons, male and female. The root having been taken from the ground the previous winter, is stacked in the yard around the factory; it is mostly of the thickness of the fingers, with here and there a piece of larger size up to a diameter of nearly 2 inches; some of it sprouting.

As required, the root is taken within the building and crushed under a heavy millstone to a pulp, water-power being employed. It is then transferred to boilers and boiled with water over a naked fire. The decoction is run off and the residual root pressed in circular bags like those used in the olive-mills. The liquor which is received into cisterns below the floor is then pumped up into copper pans, in which the evaporation is conducted also over the naked fire—even to the very last, care being taken by constant stirring to avoid burning the extract. The extract or pasta is removed from the pan while warm, and taken in small quantities to an adjoining apartment where a number of women are employed in rolling it into sticks. It is first weighed into portions, each of which the woman seated at the end of a long table tears with her hand into about a dozen pieces. These are passed to the women sitting next who roll them with their hands into cylindrical sticks, the table on which the rolling is done being of wood, and the pasta moistened with oil to prevent its adhesion to the hands. Near the further end of the table are some frames made of marble or metal, clean and bright, so arranged as to bring the sticks when rolled in them to the proper length and thickness. When thus adjusted, they are carefully ranged on a board, and a woman then stamps them with the name of the manufacturer. Lastly the sticks laid on boards are stacked up in a room to dry.

In some establishments the vacuum-pan has been introduced for the inspissation of the decoction. At the great manufactory of Mr. A. O. Clarke at Sokia near Smyrna, all the processes are performed by steam power.

Description—Liquorice juice of good quality is met with in cylindrical sticks stamped at one end with the maker’s name or mark. They are of various sizes, but generally not larger than 6 to 7 inches long by about an inch in diameter. They are black, when new or warm slightly flexible, but breaking when struck, and then displaying a sharp-edged fracture, and shining conchoidal surface on which a few air bubbles are perceptible; thin splinters are translucent. The extract has a special odour and dissolves in the mouth with a peculiar strong sweet taste. By complete drying, it loses from 11 to 17 per cent. of water.

Several varieties of Stick Liquorice are met with in English commerce, and command widely different prices. The most famous is the Solazzi Juice, manufactured at Corigliano, a small town of Calabria in the gulf of Taranto, at an establishment belonging to the sons of Don Onorato Gaetani, duke of Laurenzano and prince of Piedimonte d’Alife, who inherited the manufacture from his father-in-law, the Cavaliere Domenico Solazzi Castriota. The Solazzi Juice destined for the English market is usually shipped at Naples; it has for many years been wholly consigned to two firms in London, and in quantity not always equal to the demand. Of the other varieties we may mention Barracco, manufactured at the establishment of Messieurs Barracco at Cotrone on the eastern coast of Calabria; Corigliano, produced at a factory at Corigliano, belonging to Baron Compagna. The sticks stamped Pignatelli are from the works of Vincenzo Pignatelli, prince of Strongoli, at Torre Cerchiora, where 300 to 400 workmen are employed.

The juice is also imported in a block form, having while warm and soft been allowed to run into the wooden case in which it is exported. This juice, which is known as Liquorice Paste, is largely imported from Spain and Asia Minor, but on account of a certain bitterness is unsuited for use as a sweetmeat.

Chemical Composition—Hard extract of liquorice, such as that just described, is essentially different in composition and properties from the Extract of Liquorice (Extractum Glycyrrhizæ) of the British Pharmacopœia.[736] The latter is a soft, hygroscopic substance, entirely soluble in cold water, whereas the so-called Spanish Juice when treated with cold water leaves a large residue undissolved.

It has been sometimes supposed that the presence of this residue indicates adulteration, but such is far from being the fact, as was conclusively shown by the researches of a French Commission appointed to investigate the process recommended by Delondre.[737] This commission subjected liquorice root to the successive action of cold water, boiling water, and lastly of steam. By the first menstruum 15 per cent., and by the second an additional 7½ per cent., were obtained of a hygroscopic extract much more soluble than commercial liquorice, and totally unsuitable for being moulded into sticks. The residue having been then exhausted by steam, 16 per cent. was obtained of an extract differing entirely from those of the previous operations. It was a dry friable substance, cracking and falling to pieces in the drying stove, having a sweet taste without acridity, not readily dissolving in the mouth, and very imperfectly soluble in cold water. This then was the substance required to give firmness to the more soluble matter, and to render possible the preparation of an extract possessing that degree of solubility and hardness which would render it an agreeable sweetmeat, as well as a permanent and stable commodity. In fact, by treating the root at once with steam according to Delondre’s process, the experimenters obtained 42 to 45 per cent. of extract having all the qualities desired in good Italian or Spanish Juice.

When the latter substance is suspended in water undisturbed, the soluble matter may be dissolved out, the stick still retaining its original form. Glycyrrhizin, which is but slightly soluble in cold water, remains to some extent in the residue, and by an alkaline solution may be afterwards extracted together with colouring matter and probably also pectin. The proportion of soluble matter which the best varieties of liquorice juice yield to cold water varies from about 60 to 70 per cent. A sample of Solazzi Juice recently examined by one of us, lost 8·4 per cent. when dried at 100° C.; it was then exhausted by 60 times its weight of cold water used in successive quantities, by which means 66·8 per cent. of soluble matter were removed. The residue consisted of minute starch granules, fragments of the root, and colouring matter partially soluble in ammonia. Small shreds of copper were also visible to the naked eye. The dried juice yielded 6·3 per cent. of ash.

Corigliano liquorice treated in the same manner gave 71·2 per cent. of extract soluble in cold water; Barracco liquorice 64·9.

The small liquorice lozenges known as Pontefract Cakes (Dunhill’s), not previously dried, gave 71 per cent. of matter soluble in cold water.

Commerce—The value of the imports of Liquorice into the United Kingdom has been for the last five years as follows:—

1868 1869 1870 1871 1872

£89,482 £83,832 £70,165 £55,120 £75,991

The last named sum represents a quantity of 28,000 cwt., of which 11,170 cwt. were furnished by Italy, and the remainder by Turkey, France, Spain and other countries.

The total exports of Liquorice Paste from Smyrna were estimated in 1872 as 1,200 to 1,400 tons (24,000 to 28,000 cwt.) per annum.

Uses—Stick liquorice is sucked as a remedy for coughs, and by children as a sweetmeat. It is also used in lozenges, and in some pharmacopœias is admitted as the raw material from which to prepare soft extract of liquorice.

The block liquorice, of which a large quantity is imported, is chiefly used in the manufacture of tobacco for smoking and chewing.

OLEUM ARACHIS.

Ground-nut oil, Earth-nut oil, Pea-nut oil, Arachis oil; F. Huile d’Arachide ou de Pistache de terre; G. Erdnussöl.

Botanical Origin—Arachis hypogæa L., a diffuse herbaceous annual plant, having stems a foot or two long, and solitary axillary flowers with an extremely long filiform calyx-tube. After the flower withers, the torus supporting the ovary becomes elongated as a rigid stalk, which bends down to the ground and forces into it the young pod, which matures its seeds some inches below the surface. The ripe pod is oblong, cylindrical, about an inch in length, indehiscent, reticulated, and contains one or two, or exceptionally even four irregularly ovoid seeds.

The plant is cultivated for the sake of its nutritious oily seeds in all tropical and subtropical countries, but especially on the west coast of Africa. It is unknown in the wild state. De Candolle[738] regards it as a native of Brazil, to which region the other species of the genus exclusively belong. But the opinion of one of us[739] is strongly in favour of the plant being indigenous to Tropical Africa, and so is that also of Schweinfurth. Arachis is one of the most universally cultivated plants throughout Tropical Africa, from Senegambia to lake Tanganyika. In Europe it has not proved remunerative.

History—The first writer to notice Ground-Nut appears to be Fernandez de Oviedo y Valdes, who lived in Hayti from a.d. 1513 to 1525; he mentions in his Cronica de las Indias[740] that the Indians cultivated very much the fruit Mani, a name still used for Arachis in Cuba and in South America. A little later, Monardes,[741] described a nameless subterraneous fruit, found about the river Maranon and held in great esteem by both Indians and Spaniards. But before, the French colonists sent in 1555 by Admiral Coligny to the Brazilian coast had become acquainted with the “Mandobi,” which Jean de Léry[742] described quite unmistakably. Good accounts and figures of it were given in the following century by Johannes de Laet (1625),[743] and by Marcgraf,[744] who calls it by its Brazilian name of Mundubi. It is enumerated by Stisser among the rare plants cultivated by him at Helmstedt (Brunswick), about the year 1697.[745]

It is only in very recent times that the value of the Ground-Nut has been recognized in Europe. Jaubert, a French colonist at Gorée near Cape Verde, first suggested about 1840 its importation as an oil-seed into Marseilles, where it now constitutes one of the most important articles of trade.[746]

Description—The fat oil of Arachis, as obtained by pressure without heat, is almost colourless, of an agreeable faint odour and a bland taste resembling that of olive oil. An inferior oil is obtained by warming the seeds before pressing them. The best oil has a sp. gr. of about 0·918; it becomes turbid at 3° C., concretes at -3° to -4°, and hardens at -7°. On exposure to air it is but slowly altered, being one of the non-drying oils. At length it thickens considerably, and assumes even in closed vessels a disagreeable rancid smell and taste.

Chemical Composition—The oil consists of the glycerides of four different fatty acids. The common Oleic Acid, C₁₈H₃₄O₂, that is to say its glycerin compound, is the chief constituent of Arachis oil. Hypogæic Acid, C₁₆H₃₀O₂, has been pointed out by Gössmann and Scheven (1854) as a new acid, whereas it is thought by other chemists to agree with one of the fatty acids obtained from whale oil. The melting point of this acid from Arachis oil is 34-35° C. The third acid afforded by the oil is ordinary Palmitic Acid, C₁₆H₃₂O₂, with a fusing point of 62° C. Arachic Acid, C₂₀H₄₀O₂, the fourth constituent, has also been met with among the fatty acids of butter and olive oil, and, according to Oudemans (1866), in the tallow of Nephelium lappaceum L., an Indian plant of the order Sapindaceæ.

When ground-nut oil is treated with hyponitric acid, which may be most conveniently evolved by heating nitric acid with a little starch, a solid mass is obtained, which yields by crystallization from alcohol Elaïdic and Gæidinic acids, the former isomeric with oleic, the latter with hypogæic acid.

Production and Commerce—The pods are exported on an immense and ever increasing scale from the West Coast of Africa. From this region, not less than 66 millions of kilogrammes, value 26 millions of francs (£1,040,000), were imported in 1867, almost exclusively into Marseilles. From the French possessions on the Senegal, 24 millions of kilogr. were exported in 1876.

The oil is exported from India where the ground-nut is also cultivated, though not on so large a scale as in Western Africa. In Europe it is manufactured chiefly at Marseilles, London, Hamburg and Berlin. The yield of the seeds varies from 42 to nearly 50 per cent. The softness of the seeds greatly facilitates their exhaustion, whether by mechanical power or by the action of bisulphide of carbon or other solvent.

Uses—Good arachis oil may be employed in pharmacy in the same way as olive oil, for which it is a valuable substitute, though more prone to rancidity. It has been introduced into the Pharmacopœia of India, and is generally used instead of olive oil in the Indian Government establishments. Its largest application is for industrial purposes, especially in soap-making.

RADIX ABRI.

Indian Liquorice; F. Liane à réglisse, Réglisse d’Amérique.

Botanical Origin—Abrus precatorius L., a twining woody shrub[747] indigenous to India, but now found in all tropical countries.

History—The plant is mentioned in the Sanskrit medical writings of Susruta, whence we may infer that it has long been employed in India. Its resemblance to liquorice was remarked by Sloane (1700), who called it Phaseolus glycyrrhites. As a substitute for liquorice, the root has been often employed by residents in the tropical countries of both hemispheres. It was introduced into the Bengal Pharmacopœia of 1844, and into the Pharmacopœia of India of 1868.

The seeds, of the size of a small pea, well known for their polish and beautiful black and red colours, have given their name of Retti to a weight (= 2³/₁₆ grains) used by Hindu jewellers and druggists.

Description—The root is long, woody, tortuous and branching. The stoutest piece in our possession is as thick as a man’s finger, but most of it is much more slender. The cortical layer is extremely thin and of a light brown or almost reddish hue. The woody part breaks with a short fibrous fracture exhibiting a light yellow interior. The root has a peculiar, disagreeable odour, and a bitterish acrid flavour leaving a faintly sweet after-taste. When cut into short lengths it has a slight resemblance to liquorice, but may easily be distinguished by means of the microscope.

Mr. Moodeen Sheriff,[748] who says he has often examined the root of Abrus both fresh and dried, remarks that it is far from abounding in sugar as generally considered;—that it does not possess any sweetness at all until it attains a certain size, and that even then its sweet taste is not always well marked. As it is often mixed in the Indian bazaars with true liquorice, he thinks the latter may have sometimes been mistaken for it.

Microscopic Structure—On a transverse section the bark exhibits some layers of cork-cells, loaded with brown colouring matter, and then, within the middle zone of the bark, a comparatively thick layer of sclerenchymatous tissue. Strong liber-fibres are scattered through the interior of the cortical tissue, but are not distributed so as to form wedge-shaped rays as met with in liquorice. In the latter the sclerenchyme (thick-walled cells) is wanting. These differences are sufficient to distinguish the two roots.

Chemical Composition—The concentrated aqueous infusion of the root of Abrus has a dark brown colour and a somewhat acrid taste accompanied by a faint sweetness. When it is mixed with an alkaline solution of tartrate of copper, red cuprous oxide is deposited after a short time: hence we may infer that the root contains sugar. One drop of hydrochloric or other mineral acid mixed with the infusion produces a very abundant flocculent precipitate, which is soluble in alcohol. If the infusion of Abrus root is mixed with a very little acetic acid, an abundant precipitate is likewise obtained, but is dissolved by an excess. This behaviour is similar to that of glycyrrhizin (see p. 181).

Berzelius observed, so long ago as 1827, that the leaves of Abrus contain a sweet principle similar to that of liquorice.

Uses—The root has been used in the place of liquorice, for which it is in our opinion a very bad substitute.

SETÆ MUCUNÆ.

Dolichi pubes vel setæ; Cowhage, Cow-itch[749]; F. Pois à gratter, Pois pouillieux; G. Juckborsten.

Botanical Origin—Mucuna pruriens DC. (Dolichos pruriens L., Stizolobium pruriens Pers., Mucuna prurita Hook.), a lofty climbing plant[750] with large, dark purple papilionaceous flowers, and downy legumes in size and shape not unlike those of a sweet pea, common throughout the tropical regions of both Africa, India and America.

History—The earliest notice we have found of this plant is that of Parkinson, who in his Theater of Plants, published in 1640, names it “Phaseolus siliquâ hirsutâ, the Hairy Kidney-Beane called in Zurrate [Surat] where it groweth, Couhage” It was subsequently described by Ray (1686), who saw the plant raised from West Indian seeds, in the garden of the Hatton family in Holborn.[751] Rheede figured it in the Hortus Malabaricus,[752] and it was also known to Rumphius and the other older botanists. We find it even in the pharmaceutical tariff of the county of Nürnberg, a.d. 1714.[753]

The employment of cowhage as a vermifuge originated in the West Indies, and is quite unknown in the East. In England the drug began to attract attention in the latter part of the last century, when it was strongly recommended by Bancroft in his Natural History of Guiana (1769), and by Chamberlaine, a surgeon of London, who published an essay[754] descriptive of its effects which went through many editions. It was introduced into the Edinburgh Pharmacopœia of 1783, and into the London Pharmacopœia of 1809. At the present day it has been almost discarded from European medicine, but has been allowed a place in the Pharmacopœia of India (1868).

The name Cowhage is Hindustani, and in the modern way is written Kiwânch, which is generally derived from the Sanskrit Kapi-Kachchu, monkey’s itch (Dr. Rice); the corruption into Cow-itch is absurd. Mucuna is the Brazilian name of another species mentioned in 1648 by Marcgraf.[755]

Description—The pods are 2 to 4 inches long, about ⁴/₁₀ of an inch wide, and contain 4 to 6 seeds; they are slightly compressed and of a dark blackish brown. Each valve is furnished with a prominent ridge running from the apex nearly to the base, and is densely covered with rigid, pointed, brown hairs, measuring about ⅒ of an inch in length. The hairs are perfectly straight and easily detached from the valves, out of the epidermis of which they rise. If incautiously touched, they enter the skin and occasion an intolerable itching.

Microscopic Structure—Under the microscope the hairs are seen to consist of a single, sharply pointed, conical cell, about ¹/₄₀ of an inch in diameter at the base, with uniform brownish walls 5 mkm. thick, which towards the apex are slightly barbed. Occasionally a hair shows one or two transverse walls. Most of the hairs contain only air; others show a little granular matter which acquires a greenish hue on addition of alcoholic solution of perchloride of iron. If moistened with chromic acid, no structural peculiarity is revealed that calls for remark. The walls however are somewhat separated into indistinct layers, the presence of which is confirmed by the refractive power displayed by the hairs in polarized light.

Chemical Composition—The hairs when treated with sulphuric acid and iodine assume a dark brown colour. Boiling solution of potash does not considerably swell or alter them. They are completely decolorized by concentrated nitric acid.

Uses—Cowhage is administered for the expulsion of intestinal worms, especially Ascaris lumbricoides and A. vermicularis, which it effects by reason of its mechanical structure. It is given mixed with syrup or honey in the form of an electuary.

The root and seeds are reputed medicinal by the natives of some part of India. The pods when young and tender may be cooked and eaten.

SEMEN PHYSOSTIGMATIS.

Faba Calabarica, Faba Physostigmatis; Calabar Bean, Ordeal Bean of Old Calabar, Eseré Nut, Chop-nut; F. Fève de Calabar; G. Calabarbohne.

Botanical Origin—Physostigma venenosum Balfour, a perennial plant resembling the common Scarlet Runner (Phaseolus multiflorus Lam.) of our gardens, but having a woody stem often an inch or two thick, climbing to a height of 50 feet or more. It grows near the mouths of the Niger and the Old Calabar River in the Gulf of Guinea.

The imported seeds germinate freely, but the plant, though it thrives vigorously in a hothouse, has not yet, we believe, flowered in Europe. It has already been introduced into India and Brazil. In the latter country Dr. Peckolt, late of Cantagallo, has raised plants which have blossomed abundantly, producing racemes of about 30 flowers each, pendent from the axils of the ternate leaves.

The flower, which is fully an inch across and of a purplish colour, has the form of Phaseolus, but is distinguished from that genus by two special characters, namely that it has the style developed beyond the stigma backwards as a broad, flat, hooked appendage,[756] and the seeds half surrounded by a deeply grooved hilum.

History—The pagan tribes of Tropical Western Africa compel persons accused of witchcraft to undergo the ordeal of swallowing some vegetable poison. One of the substances employed in this horrid custom is the seed under notice, which is administered in substance or in the form of emulsion, or even as a clyster. It was first made known in England by Dr. W. F. Daniell about the year 1840, and subsequently alluded to in a paper read by him before the Ethnological Society in 1846.[757] The highly poisonous effects of the bean were observed in 1855 by Christison[758] in his own person, and in 1858 by Sharpey, who administered it to frogs.

Before the seed became an object of commerce, it was regarded by the natives with some mystery and was reluctantly parted with to Europeans. It was moreover customary in Old Calabar to destroy the plant whenever found, a few only being reserved to supply seeds for judicial purposes, and of these seeds the store was kept in the custody of the native chief. In 1859, the Rev. W. C. Thomson, a missionary on the West Coast of Africa, forwarded the plant to Professor Balfour of Edinburgh, who figured and described it as a type of a new genus.[759]

Fraser of Edinburgh (about 1863 or earlier) discovered the specific power of the seed in contracting the pupil, when the alcoholic extract is applied to the eye. These myotic effects, counteracting those of atropine and hyoscyamine, were further examined by many other experimenters on mammals or birds. The action of the poison when taken internally was found rapidly to affect the cardiac contractions and finally to paralyze the heart.

Description—The fruit of Physostigma is a dehiscent, oblong legume about 7 inches in length, containing 2 or 3 seeds. The latter, commonly known as Calabar Beans, are 1 to 1⅜ inches long, about ⁶/₈ of an inch broad, and ⁴/₈ to ⅝ of an inch in thickness, weighing on an average twenty seeds, 67 grains each.

They have an oblong, subreniform outline, one side being straight or but slightly incurved, the other boldly arched. The latter is marked by a broad furrow, ⅛ of an inch wide, bordered with raised edges, and running from the micropyle, which is a small funnel-shaped depression, quite round the opposite end of the seed. In the middle of this remarkable furrow the raphe is seen as a long raised suture running from end to end. The surface of the seed is somewhat rough, but has a dull polish; it is of a deep chocolate-brown, passing into a lighter tint on the ridges bordering the furrow. The latter is black, dull, and finely rugose.

When the seed is broken the cotyledons are found adherent to the testa, with a large cavity between them. The air thus included causes the seeds to float on water, but they sink immediately when broken. After digestion for some hours in warm water, the testa having been previously cracked, the whole seed softens and swells so that its structure may be easily studied. Each cotyledon is then seen to be marked on the hilum-side by a long shallow furrow, at one end of which, just below the micropyle, lies the plumule and radicle. A dark brown inner membrane, constituting part of the testa, surrounds the cotyledons.

The seeds have scarcely any taste, or not more than an ordinary bean; nor in the dry state have they any odour. After being boiled, or when their alcoholic tincture is evaporated, an odour suggesting cantharides is developed.

Microscopic Structure—The cotyledons are built up of large globular or ovoid cells, those of the outermost layer being smaller and of rather cubic form. This parenchyme is loaded with starch granules, frequently as much as 50 mkm. in diameter. Their interior part is less distinctly stratified than the outer; the hollow centre radiates in various directions around the axis of the ovate granule. Polarized light does not show a cross as in other more globular starch granules, but two elliptic curves approaching one another near the axis of the granule. Similar starch granules are commonly met with in the seeds of Leguminosæ.

In the Calabar seeds the starch is accompanied by numerous particles of albuminous matter becoming distinctly perceptible by addition of iodine, which imparts to them an orange colouration.

The shell of the seed is built up of four different layers; the prevailing layer consists of very long, simply cylindrical cells, densely packed so as to form only one radial row. Tison[760] has endeavoured to ascertain in what region of the seed the active principle is lodged; and he has arrived at the conclusion that its seat is the granular protoplasmic particles, which alone acquire an orange tint by the action of weak caustic alkalis.

Chemical Composition—Jobst and Hesse[761] proved in 1863 that the poisonous nature of Calabar bean depends upon an alkaloid, to which they gave the name Physostigmine. It is obtained by the method generally adopted for extracting analogous substances, that is, by precipitating one of its salts from an aqueous solution by bicarbonate of sodium, and dissolving out the base with ether or benzol. As extracted by these chemists, physostigmine is an amorphous mass of decidedly alkaline reaction, soluble in much water and in acids. On exposure to the air the solution soon becomes red, or sometimes intensely blue, a partial decomposition of the alkaloid taking place. The red coloration may even be observed in the aqueous infusion of a few cotyledons. It disappears by sulphuretted hydrogen or sulphurous acid, but returns if these reducing agents are allowed to evaporate.

Hesse[762] ascertained (1867) that physostigmine consists of C₃₀H₂₁N₃O₄; he now obtained it perfectly colourless and tasteless, softening at 40° C., fusing at 45°, but not supporting a heat of 100° C., without decomposition, which is manifested by a red coloration.

In 1865 Vée and Leven,[763] by treating the powdered unpeeled seed in nearly the same way, prepared an alkaloid which they called Eserine. It differs from Hesse’s physostigmine in that it forms colourless, rhomboidal, tabular crystals of a bitter taste, melting at 90° C. It dissolves easily in ether, alcohol, or chloroform, but very sparingly in water. The last named solution is alkaline, and reddens by exposure to the air.

It is assumed by some writers, as Tison,[764] that eserine is only the pure form of physostigmine; but at present we feel hardly warranted in admitting the identity of the two substances.

Harnack and Witkowski in 1876 ascertained the presence of another alkaloid in the seed, which they called Calabarine. It is nearly insoluble in ether and also very different from physostigmine in its physiological action, but somewhat similar to strychnine. Calabarine is consequently not to be found in those preparations of calabar bean which have been obtained or purified by means of ether.

Hesse (1878) exhausted the cotyledons of Physostigma with petroleum ether, and obtained crystals of a new indifferent substance C₂₆H₄₄+OH₂, which he called Phytosterin. It is closely allied to Cholesterin, but, in its solution in chloroform, devoid of rotatory power and melting at 133°. Cholesterin melts at 145°, and deviates, in its ethereal solution, the ray of polarized light to the left. Phytosterin also occurs in peas; Hesse suggests that the crystallized appearance of alkaloids as prepared by former observers was perhaps due to phytosterin.

From the cotyledons per se, cold water extracts mucilage, precipitable by neutral acetate of lead. The watery infusion contains also albumin, which may be coagulated by heat or by alcohol. The infusion is colourless, does not redden litmus, nor does it contain sugar in appreciable proportion; a few drops of solution of potash cause it to assume an orange colour. An infusion of the shell of the seed is already of this colour, but the tint is intensified by caustic alkali.

The cotyledons yield to boiling ether ½ to ⅓ per cent. of fatty oil, and after exhaustion by ether and alcohol, afford to cold water 12 per cent. of albuminous and mucilaginous constituents. The proportion of starch according to Teich[765] amounts to 48 per cent., the albuminous matter to 23 per cent. The entire seed furnishes 3 per cent. of ash, chiefly phosphate of potash. These constituents do not widely differ in proportion from those found in the common bean, which yields 23 to 25 per cent. of albuminous matters, and 32 to 38 per cent. of starch, besides 1 to 3 per cent. of oil.

The shells of Calabar bean are stated by Fraser to be by no means devoid of active principle.

Vée asserts that if to a solution of eserine, a little potash, lime, or carbonate of sodium be added, there is developed a red colour which rapidly increases in intensity. This colour is transient, passing into yellow, green and blue. If chloroform is shaken with such coloured solution, it takes up the colour; ether on the other hand remains uncoloured.

Uses—Calabar has been hitherto chiefly employed as an ophthalmic medicine, for the purpose of contracting the pupil. It has however been occasionally administered in tetanus and in neuralgic, rheumatic, and other diseases.

Adulteration—Other seeds are sometimes fraudulently mixed with Calabar beans. We have noticed in particular those of a Mucuna and of the Oil Palm, Elæis guineensis Jacq. The slightest examination suffices for their detection.

KINO.

Kino, Gum Kino, East Indian Kino; F. and G. Kino.

Botanical Origin—Pterocarpus Marsupium Roxb., a handsome tree 40 to 80 feet high, frequent in the central and southern parts of the Indian Peninsula and also in Ceylon, and affording a valuable timber. In the Government forests of the Madras Presidency, it is one of the reserved trees, the felling of which is placed under restrictions.

Pt. indicus Willd., a tree of Southern India, the Malayan Peninsula and the Indian and Philippine Islands, is capable of yielding kino, and is the source of the small supplies of that drug that were formerly shipped from Moulmein.

Several other plants afford substances bearing the name of Kino, which will be noticed at the conclusion of the present article.

History—The introduction of kino into European medicine is due to Fothergill, an eminent physician and patron of economic botany of the last century. The drug which Fothergill examined was brought from the river Gambia in West Africa as a rare sort of Dragon’s Blood, and was described by him in 1757[766] under the name of Gummi rubrum astringens Gambiense. It had been noticed at least twenty years before as a production of the Gambia, by Moore, factor to the Royal African Company, who says that the tree yielding it is called in the Mandingo language Kano.[767] Specimens of this tree were sent to England in 1805 by the celebrated traveller Mungo Park, and recognized some years later as identical with the Pterocarpus erinaceus of Poiret.

It seems probable that African kino continued to reach England for some years, for we find “Gummi rubrum astringens” regularly valued in the stock of a London druggist[768] from 1776 to 1792.

Duncan in the Edinburgh Dispensatory of 1803, while asserting that “kino is brought to us from Africa,” admits that some, not distinguishable from it, is imported from Jamaica. In a later edition of the same work (1811), he says that the African drug is no longer to be met with, and alludes to its place being supplied by other kinds, as that of Jamaica, that imported by the East India Company, and that of New South Wales derived from Eucalyptus resinifera Sm. It will thus be seen that at the commencement of the present century several substances, produced in widely distant regions, bore the name of Kino. That however which was principally used in the place of the old African drug, was East Indian Kino, the botanical origin of which was shown by Wight and by Royle[769] (1844-46) to be Pterocarpus Marsupium Roxb.,—a tree which, curiously enough, is closely allied to the kino tree of Tropical Africa.

This is the drug which is recognized as legitimate kino in all the principal pharmacopœias of Europe. It appears to have been first prepared for the European market in the early part of the present century, on a plantation of the East India Company called Anjarakandy, a few miles from Tellicherry on the Malabar Coast; but as we learn from our friend Dr. Cleghorn, it was not grown there but on the ghats a short distance inland.

Extraction—Kino is the juice of the tree, dried without artificial heat.[770] As it exudes, it has the appearance of red currant jelly, but hardens in a few hours after exposure to the air. In the Government forests of the Malabar Coast whence the supplies are obtained, permission to collect the drug is granted on payment of a small fee, and on the understanding that the tapping is performed skilfully and without damage to the timber. The method pursued is this:—A perpendicular incision with lateral ones leading into it, is made in the trunk, at the foot of which is placed a vessel to receive the outflowing juice. This juice soon thickens, and when sufficiently dried by exposure to the sun and air, is packed into wooden boxes for exportation.

Description—Malabar kino[771] consists of dark, blackish-red, angular fragments rarely larger than a pea, easily splitting into still smaller pieces, which are seen to be perfectly transparent, of a bright garnet hue, and amorphous under the microscope. In cold water they sink, but partially dissolve by agitation, forming a solution of very astringent taste, and a pale flocky residue. The latter is taken up when the liquid is made to boil, and deposited on cooling in a more voluminous form. Kino dissolves almost entirely in spirit of wine (·838), affording a dark reddish solution, acid to litmus paper, which by long keeping sometimes assumes a gelatinous condition. It is readily soluble in solution of caustic alkali, and to a large extent in a saturated solution of sugar.

Chemical Composition—Cold water forms with kino a reddish solution, which is at first not altered if a fragment of ferrous sulphate is added. But a violet colour is produced as soon as the liquid is cautiously neutralized. This can be done by diluting it with common water (containing bicarbonate of calcium) or by adding a drop of solution of acetate of potassium. Yet the fact of kino developing an intense violet colour in presence of a proto-salt of iron, may most evidently be shown by shaking it with water, and iron reduced by hydrogen. The filtered liquid is of a brilliant violet, and may be evaporated at 100° without turning green; the dried residue even again forms a violet solution with water. By long keeping the violet liquid gelatinizes. It is decolorized by acids, and turns red on addition of an alkali, whether caustic or bicarbonated. Catechu, as well as crystallized catechin, show the same behaviour, but these solutions quickly turn green on exposure to air.

Solutions of acids, of metallic salts, or of chromates produce copious precipitates in an aqueous solution of kino. Ferric chloride forms a dirty green precipitate, and is at the same time reduced to a ferrous salt. Dilute mineral acids or alkalis do not occasion any decided change of colour, but the former give rise to light brownish-red precipitates of Kino-tannic Acid. By boiling for some time an aqueous solution of kino-tannic acid, a red precipitate, Kino-red, is separated.

Kino in its general behaviour is closely allied to Pegu catechu, and yields by similar treatment the same products, that is to say, it affords Pyrocatechin when submitted to dry distillation, and Protocatechuic Acid together with Phloroglucin when melted with caustic soda or potash.

Yet in catechu the tannic acid is accompanied by a considerable amount of catechin, which may be removed directly by exhaustion with ether. Kino, on the other hand, yields to ether only a minute percentage of a substance, whose scaly crystals display under the microscope the character of Pyrocatechin, rather than that of catechin, which crystallizes in prisms. The crystals extracted from kino dissolve freely in cold water, which is not the case with catechin, and this solution assumes a fine green if a very dilute solution of ferric chloride is added, and turns red on addition of an alkali. This is the behaviour of catechin as well as of pyrocatechin; but the difference in solubility speaks in favour of the crystals afforded by kino being pyrocatechin rather than catechin.

We thought pyrocatechin must also occur in the mother plant of kino, but this does not prove to be the case, no indication of its presence being perceptible either in the fresh bark or wood.[772]

Etti (1878) extracted from kino colourless prisms of Kinoïn by boiling the drug with twice its weight of hydrochloric acid, about 1·03 sp. gr. On cooling, kino-red separates, very little of it remaining in solution together with kinoïn. The latter is extracted by exhausting the liquid with ether, which by evaporation affords crystals of kinoïn. They should be recrystallized from boiling water; they agree with the formula C₁₄H₁₂O₆, which is to be regarded as that of a methylated gallic ether of pyrocatechin, viz., C₆H₄ (OCH₃) C₇H₅O₅.

Kinoïn by heating it to 130° C. gives off water and turns red:

2 C₁₄H₁₂O₆ = OH₂ · C₂₈H₂₂O₁₁.

The latter product is an amorphous mass agreeing with kino-red; by heating it at 160-170° it again loses water, thus affording another anhydride.

Etti succeeded in preparing methylic chloride, pyrocatechin CH₄(OH)₂ as well as gallic acid C₇H₆O₅, by decomposing kinoïn.

We have prepared kinoïn from Australian kino (see page 198), but failed in obtaining it from Malabar kino, which however Etti states to have used. Kino affords about 1½ per cent. of kinoïn.

The solutions of kinoïn turn red on addition of ferric salts.

Commercial kino yielded us 1·3 per cent. of ash.

Commerce—The quantity of true kino collected in the Madras forests is comparatively small, probably not exceeding a ton or two annually. The drug is often shipped from Cochin.

Uses—Kino is administered as an astringent. It is said to be used in the manufacture of wines, and it might be employed if cheap enough in tanning and dyeing.

Other sorts of Kino.

1. Butea Kino, Butea Gum, Bengal Kino, Palas or Pulas Kino, Gum of the Palas or Dhak Tree.

This is an exudation from Butea frondosa Roxb. (Leguminosæ), a tree of India and Burma, well known under the name of Palas or Dhak, and conspicuous for its splendid, large, orange, papilionaceous flowers.[773] According to Roxburgh it flows during the hot season from natural fissures or from wounds made in the bark, as a red juice which soon hardens into a ruby-coloured, brittle, astringent gum.

Authentic specimens of this kino have been placed at our disposal by Mr. Moodeen Sheriff of Madras and by Dr. J. Newton of Bellary. That received from the first-named gentleman consists of flattish, angular fragments (the largest about ½ an inch across) and small drops or tears of a very dark, ruby-coloured gum, which when held to the light is seen to be perfectly transparent. The flat pieces have been mostly dried on leaves, an impression of the veins of which they retain on one side, while the other is smooth and shining. The substance has a pure astringent taste, but no odour. It yielded us 1·8 per cent. of ash and contained 13·5 per cent. of water. Ether removes from it a small quantity of pyrocatechin. Boiling alcohol dissolves this kino to the extent of 46 per cent.; the solution which is but little coloured, produces an abundant greyish-green precipitate with perchloride of iron, and a white one with acetate of lead. It may be hence inferred that a tannic acid, probably kino-tannic acid, constitutes about half the weight of the drug, the remainder of which is formed of a soluble mucilaginous substance which we have not isolated in a state of purity. By submitting the Butea kino of Mr. Moodeen Sheriff to dry distillation we obtained pyrocatechin.

The sample from Dr. Newton is wholly in transparent drops and stalactitic pieces, considerably paler than that just described, but of the same beautiful ruby tint. The fragments dissolve freely and almost completely in cold water, the solution being neutral and exhibiting the same reactions as the former sample.

Butea kino, which in India is used in the place of Malabar kino, was long confounded with the latter by European pharmacologists, though the Indian names of the two substances are quite different. It is not obtained exclusively from B. frondosa, the allied B. superba Roxb. and B. parviflora Roxb. affording a similar exudation.

2. African or Gambia Kino.—Of this substance we have a specimen collected by Daniell[774] in the very locality whence it was obtained by Moore in 1733 (see p. 195), and by Park at the commencement of the present century. The tree yielding it, which still bears the Mandingo name Kano, and grows to a height of 40 to 50 feet, is Pterocarpus erinaceus Poiret, a native of Tropical Western Africa from Senegambia to Angola. The juices exude naturally from crevices in the bark, but much more plentifully by incisions; it soon coagulates, becoming deep blood-red and remarkably brittle. That in our possession is in very small, shining, angular fragments, which in a proper light appear transparent and of a deep ruby colour. In solubility and chemical characters, we can trace no difference between it and the kino of the allied Pt. Marsupium Roxb. This kino does not now find its way to England as a regular article of trade. From the statement of Welwitsch, it appears that the Portuguese of Angola employ it under the name of Sangue de Drago.[775]

3. Australian, Botany Bay, or Eucalyptus Kino.—For some years past, the London drug market has been supplied with considerable quantities of kino from Australia; in fact at one period this kino was the only sort to be purchased.

As it is the produce of numerous species of Eucalyptus, it is not surprising that it presents considerable diversity of appearance. The better qualities closely agree with Pterocarpus kino. They are in dark reddish-brown masses or grains, which when in thin fragments are seen to be transparent, of a garnet red hue and quite amorphous. The substance is mostly collected by the sawyers and wood-splitters. It is found within the trunks of trees of all sizes, in flattened cavities of the otherwise solid wood which are often parallel to the annual rings. In such place the kino, which is at first a viscid liquid, becomes inspissated and subsequently hard and brittle. It may also be obtained in a liquid state by incisions in the stems of growing trees: such liquid kino has occasionally been brought into the London market; it is a viscid treacle-like fluid, yielding by evaporation about 35 per cent. of solid kino.[776]

Authentic specimens of the kino of 16 species of Eucalyptus sent from Australia by F. von Müller, have been examined by Wiesner of Vienna.[777] He found the drug to be in most cases readily soluble in water or in spirit of wine, the solution being of a very astringent taste. The solution gave with sulphuric acid a pale red, flocculent precipitate of Kino-tannic Acid; with perchloride of iron (as in common kino) a dusky greenish precipitate,—except in the case of the kino of E. obliqua L’Hér. (Stringy-bark Tree), the solution of which was coloured dark violet.

Wiesner further states, that Eucalyptus kino affords a little Catechin[778] and Pyrocatechin. It contains no pectinous matter, but in some varieties a gum-like that of Acacia. In one sort, the kino of E. gigantea Hook,[779] gum is so abundant that the drug is nearly insoluble in spirit of wine.

By Etti’s process, as given at page 197, we obtained kinoïn from an Australian Kino, which contained numerous fragments of the wood. We noticed that both Australian and Malabar kino emitted a somewhat balsamic odour, when they were treated with hydrochloric acid.

From this examination, it is evident that the better varieties of Eucalyptus kino, such for instance as those derived from E. rostrata Schlecht. (Red or White Gum, or Flooded Gum of the colonists), E. corymbosa Sm. (Blood-wood) and E. citriodora Hook., possess the properties of Pterocarpus kino and might with no disadvantage be substituted for it.

LIGNUM PTEROCARPI.

Lignum Santalinum rubrum, Santalum rubrum; Red Sanders Wood, Ruby Wood; F. Bois de Santal rouge; G. Rothes Sandelholz, Caliaturholz.

Botanical Origin—Pterocarpus santalinus Linn. fil.—A small tree not often exceeding 3½ to 4 feet in girth, and 20 to 25 feet in height; it is closely related to Pt. Marsupium Roxb., from which it differs chiefly in having broader leaflets always in threes. It is a native of the southern part of the Indian Peninsula, as Canara, Mysore, Travancore and the Coromandel Coast, but also occurs in Mindanao, in the southern Philippines. In India the districts in which the wood is at present chiefly obtained are the forests of the southern portion of the Kurnool Hills, Cuddapah and North Arcot (W. and N.W. of Madras). The tree is now being raised in regular plantations.[780]

The wood is a staple article of produce, and the felling of the trees is strictly controlled by the forest inspectors. The fine trunk-wood is highly valued by the natives for pillars in their temples and other buildings, as well as for turnery. The stumps and roots are exported to Europe as a dye-stuff, mostly from Madras.

History—It is difficult to tell whether the appellation Red Sandal-wood used in connexion with Yellow and White Sandal-wood by some of the earlier writers on drugs, was intended to indicate the inodorous dyewood under notice or the aromatic wood of a species of Santalum. Yet when Marco Polo[781] alludes to the sandal-wood imported into China, and to the red sandal (“Cendal vermeil”) which grows in the island of Necuveran (Nicobar), it is impossible to doubt that he intended by this latter name some such substance as that under notice.

Garcia de Orta, who wrote at Goa in the middle of the 16th century, clearly distinguished the fragrant sandal of Timor from the red inodorous wood of Tenasserim and the Coromandel Coast. It is remarkable that the wood of Pt. santalinus is distinguished to the present day in all the languages of India by names signifying red-coloured sandal-wood, though it has none whatever of the peculiarities of the odorous wood of Santalum. Red Sanders Wood was formerly supposed to possess medicinal powers: these are now disregarded, and it is retained in use only as a colouring agent.

During the middle ages, it was used as well as alkanet for culinary purposes, such as the colouring of sauces and other articles of food. The price in England between 1326 and 1399 was very variable, but on an average exceeded 3s. per lb.[782] Many entries for the purchase of Red Sanders along with spices and groceries, occur in the accounts of the Monastery of Durham, a.d. 1530-34.[783]

Description—The wood found in English commerce is mostly that of the lower parts of the stem and that of the thickest roots. It appears in the market in ponderous, irregular logs, rarely exceeding the thickness of a man’s thigh and commonly much smaller, 3, 4 or 5 feet in length; they are without bark or sapwood, and are externally of a dark colour. The internal wood is of a deep, rich, blood-red, exhibiting in transverse section zones of a lighter tint, and taking a fine polish.

At the present day, druggists generally buy the wood rasped into small chips, which are of a deep reddish-brown hue, tasteless and nearly without odour.

Microscopic Structure—The wood is built up for the greater part of long pointed cells, having thick walls (libriform). Through this ligneous tissue, there are scattered small groups of very large vessels. In a direction parallel to the circumference of the stem, there are less coloured small parenchymatous layers, running from one vascular bundle to another. The whole tissue is finally traversed by very narrow medullary rays, which are scarcely perceptible to the unaided eye. The parenchymatous cells are each loaded with one crystal of oxalate of calcium, which are so large that, in a piece of the wood broken longitudinally, they may be distinguished without a lens. The colouring matter is contained especially in the walls of the vessels and the ligneous cells.

Chemical Composition—Cold water or fatty oil (almond or olive) abstracts scarcely anything from the wood, and hot water but very little. On the other hand, ether, spirit of wine, alkaline solutions, or concentrated acetic acid, readily dissolves out the colouring matter. Essential oils of bitter almond or clove take up a good deal of the red substance; that of turpentine none at all. This resinoid substance, termed Santalic Acid or Santalin,[784] is said to form microscopic prismatic crystals of a fine ruby colour, devoid of odour and taste, fusing at 104° C., insoluble in water but neutralizing alkalis and forming with them uncrystallizable salts.

Weidel (1870) exhausted the wood with boiling water, containing a little potash, and obtained by means of hydrochloric acid a red precipitate, which was redissolved in boiling alcohol and then furnished colourless crystals of Santal, C₈H₆O₃. They are devoid of odour or taste, not soluble in water, benzol, chloroform, bisulphide of carbon, and but sparingly in ether. Santal yields with potash a faintly yellow solution which soon turns red and green. The wood afforded Weidel not more than 3 per mille of santal.

Cazeneuve (1874)[785] mixed 4 parts of the wood with 1 part of slaked lime, and exhausted the dried powder with ether containing a little alcohol. After the evaporation of the ether, a small amount of colourless crystals of Pterocarpin was obtained, which were purified by recrystallization from boiling alcohol. They melt at 83° C., and are abundantly soluble in chloroform, in bisulphide of carbon, very little in cold alcohol, not at all in water. Pterocarpin agrees with the formula C₁₇H₁₆O₅. It yields a red solution with concentrated sulphuric acid, and a green with nitric acid 1·4 sp. gr. By submitting it to destructive distillation pyrocatechin appears to be formed.

Franchimont (1879) assigns the formula C₁₇H₁₆O₆ to another principle of Red Sanders Wood, which he isolated by means of alcohol. It is an amorphous substance, melting at 105°. By extracting the wood with a solution of carbonate of sodium, Hagenbach (1872) obtained a fluorescent solution. Red Sanders Wood yielded us of ash only 0·8 per cent.

Commerce—In the official year 1869-70, Red Sanders Wood produced to the Madras Government a revenue of 26,015 rupees (£2,601). The quantity taken from the forests was reported as 1,161,799 lb.

Uses—Red Sanders Wood is scarcely employed in pharmacy except for colouring the Compound Tincture of Lavender; but it has numerous uses in the arts. The latter applies also to the wood of Pterocarpus angolensis DC., which is largely exported from the French colony of Gaboon; it is the “Santal rouge d’Afrique of the French,” or Barwood of the English commerce.

BALSAMUM TOLUTANUM.

Balsam of Tolu; F. Baume de Tolu; G. Tolubalsam.

Botanical Origin—Myroxylon Toluifera H B K. (Toluifera Balsamum Miller, Myrospermum toluiferum A. Rich.),[786] an elegant and lofty evergreen tree with a straight stem, often as much as 40 to 60 feet from the ground to the first branch. It is a native of Venezuela, and New Granada,—probably also of Ecuador and Brazil.

History—The first published account of Balsam of Tolu, is that of the Spanish physician Monardes, who in his treatise on the productions of the West Indies, which in its complete form first appeared at Seville in 1574,[787] relates how the early explorers of South America observed that the Indians collected this drug by making incisions in the trunk of the tree. Below the incisions they affixed shells of a peculiar black wax to receive the balsam, which being collected in a district near Cartagena called Tolu, took its name from that place. He adds that it is much esteemed both by Indians and Spaniards, that the latter buy it at a high price, and that they have lately brought it to Spain, where it is considered to be as good as the famous Balsam of Mecca.

Francisco Hernandez, who lived in 1561-1577 in Mexico, stated[788] that the balsam of the province of Tolu was thought to be quite as useful as, if not superior to, “balsamum indicum,” i.e. peruvianum.

A specimen agreeing with this description was given to Clusius[789] in 1581 by Morgan, apothecary to Queen Elizabeth, but the drug was certainly not common till a much later period. In the price-list of drugs of the city of Frankfort of 1669, Balsamus tolutanum (sic) is expressly mentioned,[790] but there can be but little doubt that Balsamum Americanum resinosum[791] or siccum or durum as occurring in many other tariffs of the 17th century, printed in Germany, was also the balsam under notice;[792] in a similar list emanating from the city of Basle in 1646,[793] we noticed B. indicum album, B. peruvianum and B. siccum,—the last with the explanatory words, “trockner Balsam in der Kürbsen” (i.e. in gourds), meaning probably balsam of Tolu.

As to the tree, of which Monardes figured a broken pod, leaflets of it, marked 1758, exist in Sloane’s herbarium. Humboldt and Bonpland saw it in several places in New Granada during their travels (1799-1804), but succeeded only in gathering a few leaves. Among recent collectors, Warszewicz, Triana, Sutton Hayes, and Seemann were successful only in obtaining leaves. Weir in 1863 was more happy, for by causing a large tree of nearly 2 feet diameter to be felled, he procured good herbarium specimens including pods, but no flowers. Owing to this tree having been much wounded for balsam, its foliage and fruits were singularly small and stunted, and its branches overgrown with lichens.

That which botanists had failed to do, has been accomplished by an ornithologist, Mr. Anton Goering, who, travelling in Venezuela to collect birds and insects, made it a special object, at the urgent request of one of us (H.), to procure complete specimens of the Balsam of Tolu tree. By dint of much perseverance and by watching for the proper season, Mr. Goering obtained in December 1868 excellent flowering specimens and young fruits, and subsequently mature seeds from which plants have been raised in England, Ceylon and Java.

Extraction—The most authentic information we possess on this subject is derived from Mr. John Weir, plant collector to the Royal Horticultural Society of London, who when about to undertake a journey to New Granada in 1863, received instructions to visit the locality producing Balsam of Tolu. After encountering considerable difficulties, Mr. Weir succeeded in observing the manner of collecting the balsam in the forest near Plato, on the right bank of the Magdalena. Mr. Weir’s information[794] may be thus summarized:—

The balsam tree has an average height of 70 feet with a straight trunk, generally rising to a height of 40 feet before it branches. The balsam is collected by cutting in the bark two deep sloping notches, meeting at their lower ends in a sharp angle. Below this V-shaped cut, the bark and wood is a little hollowed out, and a calabash of the size and shape of a deep tea-cup is fixed. This arrangement is repeated, so that as many as twenty calabashes may be seen on various parts of the same trunk. When the lower part has been too much wounded to give space for any fresh incisions, a rude scaffold is sometimes erected, and a new series of notches made higher up. The balsam-gatherer goes from time to time round the trees with a pair of bags of hide, slung over the back of a donkey, and empties into them the contents of the calabashes. In these bags the balsam is sent down to the ports where it is transferred to the cylindrical tins in which it reaches Europe. The bleeding of the trees goes on for at least eight months of the year, causing them ultimately to become much exhausted, and thin in foliage.

In some districts, as we learn from another traveller, it is customary to let the balsam flow down the trunk into a receptacle at its base, formed of the large leaf of a species of Calathea.

From the observations of Mr. Weir, it appears that the balsam tree is plentifully scattered throughout the Montaña around Plato and other small ports on the right bank of the Magdalena. He states that he saw at least 1,500 lb. of the drug on its way for exportation. From another source, we know that it is largely collected in the valley of the Sinu, and in the forests lying between that river and Cauca. None is collected in Venezuela.

Description—Balsam of Tolu freshly imported is a light brown, slow-flowing resin, soft enough to be impressible with the finger, but viscid on the surface.[795] By keeping, it gradually hardens so as to be brittle in cold weather, but it is easily softened by the warmth of the hand. Thin layers show it to be quite transparent and of a yellowish brown hue. It has a very agreeable and delicate odour, suggestive of benzoin or vanilla, especially perceptible when the resin is warmed, or when its solution in spirit is allowed to evaporate on paper. Its taste is slightly aromatic with a barely perceptible acidity, though its alcoholic solution decidedly reddens litmus.

In very old specimens, such as those which during the last century reached Europe in little calabashes[796] of the size and shape of an orange, the balsam is brittle and pulverulent, and exhibits when broken a sparkling, crystalline surface. This old balsam is of a fine deep amber tint and superior fragrance.

When Balsam of Tolu is pressed between two warmed plates of glass so as to obtain it in a thin even layer, and then examined with a lens, it exhibits an abundance of crystals of cinnamic acid. Balsam of Tolu dissolves easily and completely in glacial acetic acid, acetone, alcohol, chloroform or solution of caustic potash; it is less soluble in ether, scarcely at all in volatile oils, and not in benzol or bisulphide of carbon. The solution in acetone is devoid of rotatory power in polarized light.

Chemical Composition—The balsam consists partly of an amorphous resin, not soluble in bisulphide of carbon, which is supposed to be the same as the dark resin precipitated by the bisulphide from balsam of Peru. Scharling (1856) assigned the formula C₁₈H₂₀O₅ to that part of the balsam which is soluble in potash.

If Tolu balsam is boiled with water, it yields to it cinnamic and benzoic acid, which we have (1877) perfectly succeeded in separating by repeated recrystallization from water; we have before us good specimens of either, showing not only different melting points (133° C. and 121° C.), but as to our crystals of benzoïc acid, isolated from the balsam as stated above, we find that they also do not evolve bitter almond oil when mixed with sulphuric acid and chromate of potassium. The acids may also be removed by boiling bisulphide of carbon.

Busse[797] showed that benzylic ethers of both benzoic and cinnamic acid are also constituents of the balsam, the cinnamate of benzyl being present in larger quantity.

Upon distilling the balsam with water, it affords 1 per cent. of Tolene, C₁₀H₁₆, boiling at about 170° C. This liquid rapidly absorbs oxygen from the air. By destructive distillation, the balsam affords the same substances as those obtainable from balsam of Peru, among which Phenol and Styrol have been observed.

Commerce—The balsam is exported from New Granada, packed in cylindrical tins holding about 10 lb. each. The quantity shipped from Santa Marta in 1870 was 2,002 lb.; in 1871, 2,183 lb.; in 1872, 1,206 lb. In 1876 from the port of Savanilla 27,180 kilogrammes are stated to have been exported.

Uses—Balsam of Tolu has no important medicinal properties. It is chiefly used as an ingredient in a pleasant-tasting syrup and in lozenges.

Adulteration—We have twice met with spurious Balsam of Tolu, but in neither instance did the fraudulent drug bear any great resemblance to the genuine.

Colophony, which might be mixed with the balsam, can be detected by warm bisulphide of carbon which dissolves it, but removes from the pure drug almost exclusively cinnamic and benzoic acid.

BALSAMUM PERUVIANUM.

Balsam umindicum nigrum; Balsam of Peru; F. Baume de Pérou, Baume de San Salvador; G. Perubalsam.

Botanical Origin—Myroxylon Pereiræ Klotzsch (Myrospermum Pereiræ Royle), a tree attaining a height of about 50 feet, and throwing out spreading, ascending branches at 6 to 10 feet from the ground.[798]

It is found in a small district of the State of Salvador in Central America (formerly part of Guatemala), lying between 13°·35 and 14°·10 N. lat., and 89° and 89°·40 W. long., and known as the Costa del Balsamo or Balsam Coast. The trees grow naturally in the dense forests; those from which the balsam is obtained are, if in groups, sometimes enclosed, in other cases only marked, but all have their distinct owners. They are occasionally rented for a term of years, or a contract is made for the produce of a certain number.

The principal towns and villages around which balsam is produced, are the following:—Juisnagua, Tepecoyo or Coyo, Tamanique, Chiltiuapan, Talnique, Jicalapa, Teotepeque, Comasagua and Jayaque. All the lands on the Balsam Coast are Indian Reservation Lands.

The Balsam of Peru tree was introduced in 1861 into Ceylon, where it flourishes with extraordinary vigour.

History—As in the case of Balsam of Tolu, it is to Monardes of Seville that we are indebted for the earliest description of the drug under notice. In a chapter headed Del Balsamo,[799] he states that at the time he wrote (1565) the drug was not new, for that it had been received into medicine immediately after the discovery of New Spain. As the conquest of Guatemala took place about 1524, we may conclude that the balsam was introduced into Europe soon afterwards.

Monardes further adds, that the balsam was in such high estimation that it sold for 10 to 20 ducats (£4 10s. to £9) the ounce; and that when taken to Rome, it fetched even 100 ducats for the same quantity. The inducement of such enormous prices brought plenty of the drug to Europe, and its value, as well as its reputation, was speedily reduced.

The description given by Monardes of extracting the balsam by boiling the chopped wood of the trunk and branches, raises a doubt as to whether the drug he had in view was exactly that now known; but he never was in America, and may have been misinformed. Evidence that our drug was in use, is afforded by Diego Garcia de Palacio, who, in his capacity of Auditor of the Royal Audiencia of Guatemala, wrote an account to Philip II., king of Spain, describing the geography and productions of this portion of his majesty’s dominions. In this interesting document, which bears date 1576 and has only recently been published,[800] Palacio tells the king of the great balsam trees of Guaymoco and of the coasts of Tonala,[801] and of the Indian method of promoting the exudation of the balsam by scorching the trunk of the tree. Prior to the conquest of the country by the Spaniards and for a short time after, balsam formed part of the tribute paid to the Indian chiefs of Cuscatlan, to whom it was presented in curiously ornamented earthen jars.

The idea of great virtues attaching to the balsam is shown by the fact that, in consequence of representations made by missionary priests in Central America, Pope Pius V. granted a faculty to the Bishops of the Indies, permitting the substitution of the balsam of Guatemala for that of Egypt, in the preparation of the chrism used in the Roman Catholic Church. This document, bearing date August 2, 1571, is still preserved in the archives of Guatemala.[802]

In the 16th century, the balsam tree grew in the warm regions of Panuco and Chiapan in Mexico, whence it was introduced into the famous gardens of Hoaxtepec near the city of Mexico, described by Cortes in his letter to Charles V. in 1552.[803]

A rude figure of the tree, certainly a Myroxylon and probably the species under notice, was published in the Thesaurus Rerum Medicarum Novæ Hispaniæ of Hernandez,[804] who also says that it had been transferred to the “Hoaxtepecences hortos” of the Mexican kings “delitiarum et magnificentiæ gratia.”

Balsam of Peru was well known in German pharmacy in the beginning of the 17th century (see article Balsamum Tolutanum).

The exports of Guatemala being shipped chiefly at Acajutla, were formerly carried to Callao, the port of Lima, whence they were transmitted to Spain. This circumstance led to the balsam acquiring the misleading name of Peru, and in part to the notion that it was a production of South America.

The history of Balsam of Peru was much amplified by a communication of the late Dr. Charles Dorat, of Sonsonate, Salvador, in 1860 to the American Journal of Pharmacy, and by still further information accompanied by drawings and specimens, transmitted to one of us in 1863.[805] These statements have lastly been confirmed again on the spot by Mr. Theophilus Wyss, a Swiss apothecary, established in San Miguel la Union, San Salvador.[806]

Extraction of the Balsam—Early in November or December, or after the last rains, the stems of the balsam trees are beaten with the back of an axe, a hammer or other blunt instrument, on four sides, a similar extent of bark being left unbruised between the parts that are beaten. The bark thus injured soon cracks in long strips, and may be easily pulled off. It is sticky as well as the surface below it, and there is a slight exudation of fragrant resin, but not in sufficient quantity to be worth collecting. To promote an abundant flow, it is customary, five or six days after the beating, to apply lighted torches or bundles of burning wood to the injured bark, whereby the latter becomes charred. About a week later, the bark either drops or is taken off, and the stem commences to exude the balsam. This is collected by placing rags (of any kind or colour), so as entirely to cover the bare wood. As these rags in the course of some days become saturated with the exudation, they are collected, thrown into an earthen vessel of water, and gently boiled and stirred until they appear nearly clean, the balsam separating and sinking to the bottom. This process goes on for some hours, the exhausted rags being from time to time taken out, and fresh ones thrown in. As the rags are removed they are wrung out in a sort of rope bag, and the balsam so saved is added to the stock. When the boiler has cooled, the water is decanted, and the balsam is poured into tecomates or gourds, ready for the market.

The balsam prepared by means of rags is termed “balsamo de trapo;” a little balsam of inferior quality is also produced, according to Wyss, by boiling the bark with water. This method affords “Tacuasonte” or “balsamo de cascara,” which is sometimes mixed with the balsamo de trapo. Tacuasonte means prepared without fire.

The Indians work a tree a second year, by bruising the bark that was left untouched the previous year. As the bark is said to be renewed in the short space of two years, it is possible to obtain from the same tree an annual yield of about 2 lb. of balsam for many years, provided a few years of rest be occasionally allowed. Clay or earth is sometimes smeared over the bare wood.

The trees sometimes exude spontaneously a greenish gum-resin of slightly bitter taste, but totally devoid of balsamic odour. It has been analyzed by Attfield (see opposite page).

Secretion of the Balsam—No observations have yet been made as to the secretion of the balsam in the wood, or the part that is played by the operation of scorching the bark. Neither the unscorched bark nor the wood, as we have received them, possess any aromatic odour.

The old accounts speak of a very fragrant resin, far more valuable than the ordinary balsam, obtained by incisions. We have made many inquiries for it, but without the least success. Such a resin is easily obtainable from the trunk of M. Toluifera.

Description—Balsam of Peru is a liquid having the appearance of molasses, but rather less viscid. In bulk it appears black, but when examined in a thin layer, it is seen to be of a deep orange-brown and perfectly transparent. It has a balsamic, rather smoky odour, which is fragrant and agreeable when the liquid is smeared on paper and warmed. It does not much affect the palate, but leaves a disagreeable burning sensation in the fauces.

The balsam has a sp. gr. of 1·15 to 1·16. It may be exposed to the air for years without undergoing alteration or depositing crystals. It is not soluble in water, but yields to it a little cinnamic and traces of benzoic acid; from 6 to 8 parts of crystallized carbonate of sodium are required to neutralize 100 parts of the balsam. It is but partially and to a small extent dissolved by dilute alcohol, benzol, ether or essential or fatty oils, not at all by petroleum ether. The balsam mixes readily with glacial acetic acid, anhydrous acetone, absolute alcohol or chloroform. Its rotatory power is very insignificant.

Chemical Composition—The peculiar process by which balsam of Peru is obtained, causes it to contain a variety of substances not found in the more natural resin of Myroxylon Toluifera; hence the two drugs, though derived from plants most closely allied, possess very different properties.

Three parts of the balsam mix readily with one part of bisulphide of carbon, yet a further addition of the latter will cause the separation of a brown flocculent resin. If the balsam be mixed with thrice its weight of bisulphide, a coherent mass of dark resin, sometimes amounting to about 38 per cent. of the balsam, is precipitated. The bisulphide of carbon forms then a perfectly transparent brown liquid. If this solution is shaken with water, the latter removes Cinnamic and Benzoic acids. To separate them, ammonia is cautiously added, yet not in excess.[807] The solution of cinnamate and benzoate thus obtained and duly concentrated, yields both these acids in white crystals on addition of acetic or hydrochloric acid.

The resin separated by means of bisulphide of carbon as above stated, is a black brittle amorphous mass, having no longer the specific odour of the balsam. It is soluble in caustic alkalis, also in alcohol; the solution in the latter which may be considerably purified by charcoal, reddens litmus, and is abundantly precipitated by an alcoholic solution of neutral acetate of lead. Kachler (1869) by melting this resin with potash obtained about ⅔ of its weight of protocatechuic acid.[808] By destructive distillation, it furnishes benzoic acid, styrol,C₈H₈, and toluol, C₇H₈.

As to the solution obtained with bisulphide of carbon, it forms, after the bisulphide has evaporated, a brownish aromatic liquid of about 1·1 sp. gr., termed Cinnameïn. This substance may also be obtained by distillation, yet less easily, on account of its very high boiling point, about 300° C.

Cinnameïn, C₁₆H₁₄O₂, is resolved by concentrated caustic lye into benzylic alcohol, C₇H₁₄O₂, and cinnamic acid, C₉H₈O₂, whence it follows that cinnameïn is Benzylic Cinnamate. This is, according to Kraut (1858, 1869, 1870) and to Kachler (1869, 1870), the chief constituent of the balsam. The former chemist obtained from it nearly 60 per cent. cinnameïn. Kachler assigns to the balsam the following composition: 46 per cent. of cinnamic acid, 32 of resin, 20 of benzylic alcohol. These latter figures however are not quite consistent: 46 parts of cinnamic acid (molecular weight = 148) would answer to 73 parts of benzylic cinnamate; and 20 parts of benzylic alcohol require on the other hand only (mol. weight = 108) 27·4 parts of cinnamic acid in order to form benzylic cinnamate (mol. = 238).

Benzylic cinnamate, prepared as above stated, is a thick liquid, miscible both with ether or alcohol, not concreting at -12° C., boiling at 305° C., yet under ordinary circumstances not without decomposition. By exposure to air, it slowly acquires an acid reaction; by prolonged action of potash, especially in an alcoholic solution, toluol is also formed. In this process, cinnamate of potassium finally forms a crystalline mass, while an oily mixture of benzylic alcohol and toluol, the so-called “Peruvin” constitutes the liquid part of the whole.

Grimaux (1868) has artificially prepared benzylic cinnamate by heating an alkaline cinnamate with benzylic chloride. Thus obtained, that substance forms crystals, which melt at 39° C., and boil at 225 to 235° C. They consequently differ much from cinnameïn.

Delafontaine (1868) is of the opinion, that cinnameïn contains besides benzylic cinnamate, cinnamylic cinnamate, C₃₆H₃₂O₄, the same substance as described under the name of styracin in the article Styrax liquida. He states that he obtained benzylic and cinnamylic alcohol when he decomposed cinnameïn by an alkali. The two alcohols however were separated only by fractional distillation.

From the preceding investigations it must be concluded, that the bark of the tree contains resin and probably benzylic cinnamate. The latter is no doubt altered by the process of collecting the balsam, which is followed on the Balsam Coast. To this are probably due the free acids in the balsam and its dark colour.

Another point of considerable interest is the fact, that the tree exudes a gum-resin, containing according to Attfield 77·4 per cent. of resin,[809] which is non-aromatic and devoid of cinnamic acid, and therefore entirely distinct from balsam of Peru. The leaves of the tree contain a fragrant oil.

Commerce—The balsam is shipped chiefly at Acajutla. It used formerly to be packed in large earthenware jars, said to be Spanish wine-jars, which, wrapped in straw, were sewed up in raw hide. These packages have of late been superseded by metallic drums, which have the advantage of being much less liable to breakage. We have no exact statistics as to the quantity exported from Central America. In the catalogue of San Salvador (quoted above, page 207, note 2) p. 39, the value of the balsam exported in 1876 from that country is stated to have been 78,189 dollars. The value of tobacco amounted to 69,717 dollars, that of coffee to 1⅓ millions of dollars, indigo to 2¼ millions.

Uses—Occasionally prescribed in the form of ointment as a stimulating application to old sores, sometimes internally for the relief of asthma and chronic cough. It is said to be also employed for scenting soap.

Adulteration—We have before us a sample of an adulterated balsam, which, we are told, is largely prepared at Bremen. It is less aromatic, less rich in acids, and contains usually much less than 38 per cent. of resin separable, as above stated, by means of bisulphide of carbon. At first sight however the adulterated drug is not so easily recognized.

Other sorts of Balsam of Peru.

The value anciently set upon balsam for religions and medicinal uses, led to its being extracted from the pods and also from trees no longer employed for the purpose; and many of the products so obtained have attracted the attention of pharmacologists.[810] Parkinson writing in 1640 observes that—“there have been divers other sorts of liquours, called Balsamum for their excellent vertues, brought out of the West Indies, every one of which for a time after their first bringing was of great account with all men and bought at great prices, but as greater store was brought, so did the prices diminish and the use decay ...”

In Salvador, the name Balsamo blanco (White Balsam) is applied to the soft resin contained in the large ducts of the legume of Myroxylon Pereiræ. This, when pressed out, forms a golden yellow, semi-fluid, granular, crystalline mass, hardening by age, having a rather unpleasant odour suggestive of melilot. Stenhouse (1850) obtained from it the neutral resin Myroxocarpin, C₂₄H₃₄O₃, in thin colourless prisms, an inch or more in length. We have succeeded in extracting it directly from the pods. This White Balsam, which is distinctly mentioned in the letter of Palacio in 1576 (see p. 206), is a scarce and valuable article, never prepared for the market. A large jar of it was sent to Pereira in 1850;[811] Guzman[812] and Wyss state that it is known in the country as “Balsamito,” or “Balsamo catolico or Virgin Balsam.”