Chapter XVIII: Part 18

[1053] Quoted before, p. 163, note 3; in the same book “_cotone storace e corallo_“ occur as articles of export from Sicily.

_Resin of Liquidambar styraciflua_ L.—a large and beautiful tree, native of North America from Connecticut and Illinois southward to Mexico and Guatemala. In the United States, where it is called _Sweet Gum_, the tree yields from natural fissures or by incision, small quantities of a balsamic resin, which is occasionally used for chewing. We have before us an excellent sample of it collected for Messrs. Wallace Brothers of Statesville, N. Carolina.[1054]

In Central America this exudation is far more freely produced; an authentic specimen from Guatemala in our possession is a pale yellow, opaque resin of honey-like consistence, becoming transparent, amber-coloured and brittle by exposure to the air. It has a rather terebinthinous, balsamic odour. In the mouth it softens like benzoin or mastich, and has but little taste. Another specimen also from Guatemala, a thick, fluid oleo-resin, of a golden brown hue, was contributed to the Paris Exhibition in 1878.

The resin of _L. styraciflua_ L. has been ascertained by Procter[1055] to contain cinnamic, but not benzoic acid. Harrison[1056] found it to contain styracin and essential oil (styrol?).

_Resin of Liquidambar formosana_ Hance—This tree, which we suppose may be the _Styrax liquida folio minore_, which Ray names[1057] as occurring in a collection of plants from Amoy, is a native of Formosa and Southern China, where it affords a dry terebinthinous resin, of agreeable fragrance when heated. Of this resin, which is used by the Chinese, a specimen collected in Formosa by Mr. Swinhoe has been presented to us by Dr. Hooker. A tree figured under the name of _Fung-heang_ in the _Pun-tsao_[1058] is, we presume, this species.

_Resin of Altingia excelsa_ Noronha (_Liquidambar Altingiana_ Bl.) =_Rasamala_= of the Javanese and Malays—The _Rasamala_ is a magnificent tree of the Indian Archipelago, Burma and Assam. In Java it yields by incisions in the trunk an odorous resin, yet only very slowly and in very small quantity; this resin is not, or at least not regularly, collected. In Burma, on the other hand, the tree affords a fragrant balsam, of which according to Waring[1059] there are two varieties, the one pellucid and of a light yellowish colour, obtained by simple incision; the other thick, dark, opaque, and of terebinthinous odour, procured by boring the stem and applying fire around the trunk.

MYRTACEÆ.

OLEUM CAJUPUTI.

_Oil of Cajuput_, _Kayu-puti Oil_; F. _Essence de Cajuput_; G. _Cajeputöl_.

=Botanical Origin=—_Melaleuca Leucadendron_ L., a tree often attaining a considerable size, with a thick spongy bark peeling off in layers, and slender, often pendulous branches. It is widely spread, and abundant in the Indian Archipelago and Malayan peninsula, and is also found in Northern Australia, Queensland, and New South Wales.

[1054] Obligingly presented to me by our friend, Dr. Squibb, Brooklyn (1879).—F. A. F.

[1055] _Proceedings of the Am. Pharm. Asso._ 1865. 160.

[1056] _Am. Journ. of Pharm._ 1874. 161.—In the same periodical (1876, 335) 300 lbs. are stated to have been collected at Dyersburg, Tenn.

[1057] _Hist. Plant._ iii. (1704), appendix p. 233.

[1058] Chap. 34. sec. 5. § 1. _Aromatic Trees._ For a modern fig., see Hooker’s _Icones Plant._ 3rd series, i. tab. 1020.

[1059] _Pharm. of India_, 1868. 88.

The tree, according to Bentham,[1060] varies exceedingly in the size, shape, and texture of the leaves, in the young shoots being silky, and the spikes silky-villous or woolly, or the whole quite glabrous, in the short and dense, or long and interrupted spikes, in the size of the flower, and in the greenish yellow, whitish, pink, or purple stamens, so that it is difficult to believe all can be forms of a single species. Yet upon examination, none of these variations are sufficiently constant or so combined, as to allow of the definition of distinct races.

The variety growing in Bouro, where the oil of cajuput has been distilled ever since the time of Rumphius, and known as _M. minor_ Smith, is described by Lesson, who visited the island in 1823, as a tree resembling an aged olive, with flowers in little globose white heads, and a trunk the stout bark of which is composed of numerous satiny layers.

=History=—Rumphius, who passed nearly fifty years in the Dutch possessions in the East Indies and died at Amboyna in 1702, is the first to give an account of the oil under notice, and of the tree from which it is obtained.[1061] From what he says, it appears that the aromatic properties of the tree are well known to the Malays and Javanese, who were in the habit of steeping its leaves in oil which they then impregnated with the smoke of benzoin and other aromatics, so obtaining an odorous liquid for anointing their heads. They likewise used cushions stuffed with the leaves, and also laid the latter in chests to keep away insects.

The fragrance of the foliage having thus attracted the attention of the Dutch, probably suggested submitting the leaves to distillation. Rumphius narrates how the oil was obtained in very small quantities, and was regarded as a powerful sudorific.

In Europe it appears to have been first noticed by J. M. Lochner,[1062] of Nürnberg, physician to the German Emperor. About the same time (1717), a ship’s surgeon, returning from the east, sold a provision of the oil to the distinguished apothecary Johann Heinrich Link at Leipzig, who published a notice on it and sold it.[1063] It began then to be quoted in the tariffs of other German apothecaries,[1064] although it was still reputed a very rare article in 1726.[1065] Somewhat larger quantities appear to have been soon imported by Amsterdam druggists.[1066] In Germany the oil took the name of _Oleum Wittnebianum_, from the recommendations bestowed on it by M. von Wittneben, of Wolfenbüttel, who was much engaged in natural sciences and long resident in Batavia.[1067] In France and England, it was however scarcely known till the commencement of the present century, though it had a place in the Edinburgh Pharmacopœia of 1788. In the _London Price Current_, we do not find it quoted earlier than 1813, when the price given is 3_s._ to 3_s._ 6_d._ per ounce, with a duty of 2_s._ 4½_d._ per ounce.

[1060] _Flora Australiensis_, iii. (1866) 142.

[1061] _Herb. Amboinense_, ii. (1741) cap. 26.

[1062] _Acad. Nat. Curios. Ephemerid. Cent._ v. vi. (Nürnberget, 1717) 157.

[1063] _Sammlung von Natur und Medicin ... Geschichten_, Leipzig, 1719. 257.

[1064] _Pharm. Journ._ vi. (1876) 1023.

[1065] Vater, _Catalog. varior. exoticor. rarissimor...._ Wittenbergæ, 1726.

[1066] Schendus van der Beck, _De Indiæ rarioribus, Act. Nat. Cur._ i., appendix (1725) 123.

[1067] Goetz, _Olei Caieput historia—Commercium Litterarium_, 1731. 3; Martini, _De Oleo Wittnebiano dissertatio_, 1751.

=Manufacture=—In the island of Bouro, in the Molucca Sea, the leaves of the _Kayu-puti_ or Aij-puti, _i.e._ _White-wood_ trees, are submitted to distillation with water, the operation being conducted in the most primitive manner, as already witnessed, about the year 1792, by Labillardière in his celebrated voyage with Lapérouse. Bickmore,[1068] an American traveller who passed three months in the island in 1865, states that it produces about 8,000 bottles of the oil annually, and that this is almost its only export. The Trade Returns of the Straight Settlements published at Singapore, show that the largest quantity is shipped from Celebes, the great island lying west of Bouro.

[1068] _Travels in the East Indian Archipelago_, Lond. 1868. 282.

=Description=—Oil of Cajuput is a transparent mobile fluid, of a light bluish-green hue, a fragrant camphoraceous odour, and bitterish aromatic taste. It has a sp. gr. of 0·926, and remains liquid even at (8°·6 F.)-13° C. It deviates the ray of polarized light to the left. On diluting it with bisulphide of carbon it becomes turbid.

=Chemical Composition=—The researches of Schmidl (1860) and of Gladstone (1872) have shown that cajuput oil consists chiefly of _Hydrate of Cajuputene_ or _Cajuputol_, C₁₀H₁₆, H₂O, which may be obtained from the crude oil by fractional distillation at 174° C. If it is repeatedly distilled from anhydrous phosphoric acid, _Cajuputene_, C₁₀H₁₆, passes over at 160-165° C.; it has an agreeable odour of hyacinths. After the cajuputene, _Isocajuputene_ distils at 177°, and _Paracajuputene_ at 310-316°, both agreeing in composition with cajuputene.

Like most essential oils having the formula C₁₀H₁₆, crude cajuput oil is capable of forming the crystallized compound C₁₀H₁₆, 3OH₂. This we have abundantly obtained by mixing 4 parts of the oil with 1 of alcohol 0·830 sp. gr., and one part of nitric acid 1·20 sp. gr.; the mixture should be allowed to stand in shallow dishes. By adding 1 vol. of absolute alcohol to 3 vol. of cajuput oil, and saturating it with anhydrous hydrochloric gas, crystals of the compound C₁₀H₁₆(HCl)₂ may be obtained. By vapour of bromine the oil acquires a beautiful green colour.

If 1 part of iodine be gradually dissolved in cajuput oil, the temperature being maintained at 50° C., fine green crystals of (C₁₀H₁₆HI)₂OH₂ are formed. They may be recrystallized from very little glacial acetic acid, but will not keep for more than a few weeks.

The green tint of the oil is due to copper, a minute proportion of which metal is usually present in all that is imported. It may be made evident by agitating the oil with water acidulated by a little hydrochloric acid. The compounds of copper with inorganic acids being comparatively of a fainter colour than the cupric salts of organic acids, the aqueous solution of chloride of copper now formed displays no longer the fine green tint. To the solution, after it has been put into a platinum capsule, a little zinc should be added, when the copper will be immediately deposited on the platinum. The liquid may be then poured off and the copper dissolved and tested. When the oil is rectified, it is obtained colourless, but it readily becomes green if in contact for a short time with metallic copper. The presence of the metal in the oil may also be shown at once by a scrap of paper which has been impregnated with fresh tincture of guaiacum wood and dried. If it is then moistened with water containing 1 per cent. of sulphocyanate of potassium, the paper turns intensely blue by the contact with the oil provided the latter contains copper.

Guibourt[1069] has however proved by experiment that the volatile oil obtained by the distillation of the leaves of several species of _Melaleuca_, _Metrosideros_ and _Eucalyptus_, has naturally a fine green hue. It is not improbable that this hue is transient, and that the contamination with copper is intentional in order to obtain a permanent green.

=Commerce=—The oil is imported from Singapore and Batavia, packed in glass beer or wine bottles. From official statements[1070] it appears that the imports into Singapore during 1871 were as under:—

From Java 445 gallons
” Manilla 200 ”
” Celebes 3,895 ”
” other places 350 ”
-----
Total 4,890 ”
-----

Of this large quantity, the greater portion was re-shipped to Bombay, Calcutta, and Cochin China.

=Uses=—Cajuput oil is occasionally administered internally as a stimulant, antispasmodic and diaphoretic: externally as a rubefacient it is in frequent use.

=Substitutes=—The oil of _Eucalyptus oleosa_ F. Muell. has, we find, the odour of cajuput; and according to Gladstone it agrees, as well as the oils of _Melaleuca ericifolia_ Sm. and _M. linariifolia_ Sm., almost entirely with cajuput oil, except in optical properties. The same is probably the case with the oil of _Eucalyptus globulus_ Labill, which Cloez (1870) states to be dextrogyre. These oils are shipped to some extent from Australia to Europe, probably as adulterants of other essential oils.

CARYOPHYLLI.

_Cloves_; F. _Girofles_, _Clous de Girofles_; G. _Gewürznelken_.

=Botanical Origin=—_Eugenia caryophyllata_ Thunberg (_Caryophyllus aromaticus_ L.), a beautiful evergreen tree, 30 to 40 feet high, resembling a gigantic myrtle, bearing numerous flowers grouped in small terminal tricotomous cymes. The flower has an inferior ovary about ½ an inch long, cylindrical, of a crimson colour, dividing at the top into 4 sepals; and 4 round concave petals larger than the calyx, imbricated in the bud like a globe, but at length spreading and soon dropping off.

The clove-tree is said to be strictly indigenous only in the five small islands constituting the proper Moluccas, namely Tarnati, Tidor, Mortir, Makiyan and Bachian.[1071] These form a chain on the west side of the large island of Jilolo, where, strange to say, the tree appears not to exist in a wild state (Crawfurd). According to Rumphius, it was introduced into Amboyna before the arrival of the Portuguese, and is still cultivated there and in the neighbouring islands of Haruku, Saparua and Nusalaut, also in Sumatra and Penang. It is likewise now found in Malacca, the Mascarene Islands, the islands of Zanzibar and Pemba on the eastern coast of Africa, and the West Indies.

[1069] _Hist. des Drog._ iii. (1869) 278.

[1070] _Blue Book of the Colony of the Straits Settlements_ for 1871, Singapore, 1872.

[1071] Though these are the original Moluccas or Clove Islands, the name has been extended to all islands east of Celebes and west of New Guinea.

The tree which is grown for the spice appears to be a cultivated variety, of lower stature and more aromatic than the wild form.

=History=[1072]—The Greek name Καρυόϕυλλον is supposed to refer to the ball-like _petals_ of the bud, which, as above described, might be compared to a small nut (κάρυον). But the name is very variably written, as γαροῦμϕουλ, καρϕούϕουλ, γαρόϕαλα,[1073] whence it becomes probable that it is not really Greek, but an Asiatic word hellenized.

Cloves have been long known to the Chinese. Mr. Mayers, late Chinese Secretary to the British Legation at Pekin, has communicated to us the interesting fact that they are mentioned by several Chinese writers as in use under the Han dynasty, B.C. 266 to A.D. 220, during which period it was customary for the officers of the court to hold the spice in the mouth before addressing the sovereign, in order that their breath might have an agreeable odour.[1074]

The Sanskrit name is “_Lavanga_,” whence the vernacular Hindustani “_Laung_.”

The first European author to mention _Caryophyllon_ is Pliny, who describes it, after _pepper_, as a grain resembling that spice but longer and more brittle, produced in India, and imported for the sake of its odour. It is doubtful whether this description really refers to cloves.

By the 4th century, cloves must have become well known in Europe, if credence can be placed in a remarkable record preserved by Vignoli,[1075] which states that the emperor Constantine presented to St. Silvester, bishop of Rome, A.D. 314-335, numerous vessels of gold and silver, incense and spices, among which last were 150 pounds of _Cloves_—a vast quantity for the period.

Kosmas Indicopleustes,[1076] in his _Topographia Christiana_ written about A.D. 547, states in the account of Taprobane (Ceylon) that silk, aloes [-wood], cloves (Καρυόϕυλλον) and sandal-wood, besides other productions, are imported thither from China, and other emporia, and transmitted to distant regions. Alexander Trallianus,[1077] who was a friend of Kosmos and a pupil of his father, prescribed in several receipts 5 or 8 cloves, καρυοϕυλλου κόκκους, from which fact it may be inferred that at his time (at Rome?) cloves were a very rare article. A century later, Paulus Ægineta[1078] distinctly described cloves as _Caryophyllon_—_ex India, veluti flores cujusdam arboris.. odorati, acres_ ... and much used for a condiment and in medicine.

[1072] For the history of the oil see our article Cortex Cinnamon, chemical composition.

[1073] Langkavel, _Botanik der späteren Griechen_, Berlin, 1866. 19.

[1074] At this period, the clove was called _Ki shêh hiang_, i.e. _fowl’s tongue spice_. The modern name _Ting hiang_, i.e. _nail-scent_ or-_spice_, was in use in the 5th or 6th century of our era.

[1075] _Liber Pontificalis, seu de Gestis Romanorum Pontificum_, Romæ, i. (1724) 94.

[1076] Migne, _Patrologiæ Cursus_, series Græca, lxxxviii. (1860) 446.

[1077] Puschman’s edition (quoted in the appendix) i. 435. 580. Alexander dedicated his work to his teacher, the father of Cosmas.

[1078] _De re medica_, lib. vii. c. 3.

In the beginning of the 8th century, the same spice is noticed by Benedictus Crispus,[1079] archbishop of Milan, who calls it _Cariophylus ater_; and in A.D. 716, it is enumerated with other commodities in the diploma granted by Chilperic II. to the monastery of Corbie in Normandy.[1080]

We find cloves among the wares on which duty was levied at Acon (the modern Acre) in Palestine at the end of the 12th century, at which period that city was a great emporium of Mediterranean trade.[1081] They are likewise enumerated in the tariff of Marseilles of A.D. 1228,[1082] in that of Barcelona of 1252[1083] and of Paris, 1296.[1084]

These facts show that the spice was a regular object of commerce at this period. But it was very costly: the Household Book of the Countess of Leicester, A.D. 1265,[1085] gives its price as 10_s._ to 12_s._ per lb., exactly the same as that of saffron. Several other examples of the high cost of the spice might be adduced.

Of the place of growth of cloves, the first distinct notice seems to be that of the Arabian geographer Ibn Khurdádbah,[1086] A.D. 869-885, who names the spice, with cocoa-nuts, sugar, and sandal-wood as produced in Java. Doubtless he was misinformed, for the clove-tree had not come so far west at that period. Marco Polo[1087] made the same mistake four centuries later: finding the spice in Java, he supposed it the growth of the island.

Nicolo Conti,[1088] a Venetian merchant who lived from A.D. 1424 to 1448 in the Indian Archipelago, learned that cloves are brought to Java from the island of Banda, fifteen days’ sail further east. With the arrival of the Portuguese at the commencement of the 16th century, more accurate accounts of the Spice Islands began to reach Europe; and Pigafetta,[1089] the companion of Magellan, gave a very good description of the clove-tree as he observed it in 1521.

The Portuguese had the principal share in the clove trade for nearly a century. In 1605 they were expelled by the Dutch, who took exclusive possession of the Moluccas and adopted extraordinary measures for keeping the traffic in their own hands. Yet notwithstanding this, large supplies of cloves reached England direct. In 1609 a ship of the East India Company called the _Consent_ arrived with 112,000 lb., the duty on which amounted to £1400 and the impost to as much more. The spice ungarbled was sold at 5_s._ 6_d._ and 5_s._ 9_d._ per lb.—of course, in bond.[1090]

[1079] _Poematium Medicum_—Migne, _Patrologiæ Cursus_, lxxxix. (1850) 374.

[1080] Pardessus, _Diplomata, Chartæ_, etc., ii. (1849) 309.

[1081] _Recueil des Historiens des Croisades, Lois_, (1843) 173.

[1082] _Méry et Guindon, Hist. des Actes ... de la municipalité de Marseille_, 1841. 373.

[1083] Capmany, _Memorias sobre la marina etc. de Barcelona_, iii. 170.

[1084] Douet d’Arcq, _Revue archéologique_, ix. (1852) 213.

[1085] _Manners and Household Expenses in England_ (Roxburgh Club), 1841. lii.

[1086] _Le Livre des routes et des provinces_, traduit par C. Barbier de Meynard, _Journ. Asiat._ sér. 6. tome v. (1865) 227.

[1087] Yule, _Marco Polo_, ii. (1871) 217.—It should however be borne in mind that the name Java was applied in a general sense by the Arab geographers to the islands of the Archipelago.

[1088] Kunstmann, _Die Kenntniss Indiens im XVᵗᵉⁿ Jahrhundert_, München, 1863. 46.

[1089] Ramusio, _Delle navigationi et viaggi_, Venetia, 1554, fol. 404b.

[1090] _Calendar of State Papers, Colonial series, East Indies_, 1862. 181.

To effect their purpose, the Dutch endeavoured to extirpate the clove-tree from its native islands, and even instituted periodical expeditions for the purpose of destroying any young trees that might have accidentally sprung up. This policy, the object of which was to confine the growth of the spice to a group of small islands of which Amboyna is the largest, has but very recently been abandoned: though the cultivation of the spice was free in all other localities, the _clove parks_ of the Amboyna islands remained the property of the Dutch Government. The original Moluccas or Clove Islands now produce no cloves at all.

The enterprise of Poivre, the French governor of Mauritius and Bourbon, so far eluded the vigilance of the Dutch, that both clove and nutmeg-trees were introduced into those islands in the year 1770.[1091] The clove-tree was carried thence to Cayenne in 1793, and to Zanzibar about the end of the century.

Crawfurd,[1092] in an excellent article of which we have made free use, aptly remarks that it is difficult to understand how the clove first came to the notice of foreign nations, considering the well ascertained fact that it has never been used as a condiment or in any other way by the inhabitants of the islands of which it is a native. We may observe however that there were some singular superstitions among the islanders with regard to the so-called _Royal Clove_ (p. 287), a tree of which on the island of Makiyan was long supposed to be unique.

=Collection=—The flower-buds of the clove-tree when young are nearly white, but afterwards become green and lastly bright red, when they must at once be gathered. This in Zanzibar is done by hand; each clove is picked singly, a moveable stage the height of the tree being used to enable the labourers to reach the upper branches. The buds are then simply dried in the sun, by which they acquire the familiar dark brown tint of the commercial article. The gathering takes place twice a year; in the Moluccas where the harvest occurs in June and December, the cloves are partly gathered by hand, and partly beaten off the tree by bamboos on to cloths spread beneath. The annual yield of a good tree is about 4½ pounds, but sometimes reaches double that quantity.

=Description=—Cloves are about ⁶/₁₀ of an inch in length, and consist of a long cylindrical calyx dividing above into 4 pointed spreading sepals which surround 4 petals, closely imbricated as a globular bud about ²/₁₀ of an inch in diameter.

The petals which are of lighter colour than the rest of the drug and somewhat translucent from numerous oil-cells, spring from the base of a 4-sided epigynous disc, the angles of which are directed towards the lobes of the calyx. The stamens which are very numerous, are inserted at the base of the petals and are arched over the style. The latter which is short and subulate, rises from a depression in the centre of the disc. Immediately below it and united with the upper portion of the calyx is the ovary, which is 2-celled and contains many ovules. The lower end of the calyx (_hypanthium_) has a compressed form; it is solid but has its internal tissue far more porous than the walls. The whole calyx is of a deep rich brown, has a dull wrinkled surface, a dense fleshy texture, and abounds in essential oil which exudes on simple pressure with the nail. Cloves have an agreeable spicy odour, and a strong biting aromatic taste.

[1091] Tessier, _Sur l’importation du Giroflier des Moluques aux Isles de France, de Bourbon et de Sechelles, et de ces isles à Cayenne_.—_Observations sur la physique_, Paris, Juillet, 1779.

[1092] _Dictionary of the Indian Islands_, 1856, article _Clove_.

The varieties of cloves occurring in commerce do not exhibit any structural differences. Inferior kinds are distinguished by being less plump, less bright in tint, and less rich in essential oil. In London price-currents, cloves are enumerated in the order of value thus: Penang, Bencoolen, Amboyna, Zanzibar.

=Microscopic Structure=—A transverse section of the lower part of a clove shows a dark rhomboid zone, the tissue on either side of which is of a lighter hue. The outer layer beneath the epidermis exhibits a large number of oil-cells, frequently as much as 300 mkm. in diameter. About 200 oil-cells may be counted in one transverse section, so that the large amount of essential oil in the drug is well shown by its microscopic characters. The above-mentioned zone is chiefly made up of about 30 fibro-vascular bundles, another stronger bundle traversing the centre of the clove. The fibro-vascular bundles, as well as the tissue bordering the oil-cells, assume a greenish black hue by alcoholic perchloride of iron. Oil-cells are also largely distributed in the leaves, petals and even the stamens of Eugenia.

=Chemical Composition=—Few plants possess any organ so rich in essential oil as the drug under consideration. The oil known in pharmacy as _Oleum Caryophylli_, which is the important constituent of cloves, is obtainable to the extent of 16 to 20 per cent. But to extract the whole, the distillation must be long continued, the water being returned to the same material.

The oil is a colourless or yellowish liquid with a powerful odour and taste of cloves, sp. gr. 1·046 to 1·058. It is a mixture of a hydrocarbon, and an oxygenated oil called _Eugenol_, in variable proportions. The former which is termed _light oil of cloves_ and comes over in the first period of the distillation, has the composition C₁₅H₂₄, a sp. gr. of 0·918 and boils at 251° C. It deviates the plane of polarization slightly to the left, and is not coloured on addition of ferric chloride; it is of a rather terebinthinaceous odour.

Eugenol, sometimes called _Eugenic Acid_, has a sp. gr. of 1·087 at 0° C., and possesses the full taste and smell of cloves. Its boiling point is 247°·5 C. With alkalis, especially ammonia and baryta, it yields crystallizable salts. Eugenol may therefore be prepared by submitting the crude oil of cloves to distillation with caustic soda; the “light oil” distils then, the eugenol, being now combined with sodium, remains in the still. It will be obtained on addition of an acid and again distilling. Eugenol is devoid of rotatory power, whence the crude oil of cloves, of which eugenol is by far the prevailing constituent, is optically almost inactive. The constitution of eugenol is given by the

{OCH₃
formula C₆H₃ {OH .
{CH·CH·CH₃

It belongs to the phenol class, and has also been met with in the fruits of Pimenta officinalis (see next article), in the Bay leaves, in Canella bark (see page 75), in the leaves and flower buds of Cinnamomum zeilanicum and in Brazilian clove-bark (_Dicypellium caryophyllatum_ Nees).

Eugenol can be converted into _Vanillin_ (see Fructus Vanillæ).

The water distilled from cloves is stated to contain, in addition to the essential oil, another body, _Eugenin_, which sometimes separates after a while in the form of tasteless, crystalline laminæ, having the same composition as eugenol.[1093] We have never met with it.

According to Scheuch (1863), oil of cloves also (sometimes) contains a little _Salicylic acid_,

{OH
C₆H₄ { ,
{COOH

which may be removed by shaking the oil with a solution of carbonate of ammonium.

_Caryophyllin_, C₂₀H₃₂O, is a neutral, tasteless, inodorous substance, crystallizing in needle-shaped prisms. We have obtained it in small quantity, by treating with boiling ether cloves, which we had previously deprived of most of their essential oil by small quantities of alcohol. E. Mylius (1873) obtained from it by nitric acid, crystals of _Caryophyllinic Acid_, C₂₀H₃₂O₆.

_Carmufellic Acid_ obtained in colourless crystals, C₁₂H₂₀O₁₆, in 1851 by Muspratt and Danson after digesting an aqueous extract of cloves with nitric acid, is a product of this treatment and not a natural constituent of cloves.

Cloves contain a considerable proportion of gum; also a tannic acid not yet particularly examined.

=Production and Commerce=—Of late years the principal locality for the production of cloves has been the islands of Zanzibar and Pemba on the east coast of Africa, which until very recently were capable of producing a maximum crop of 10½ millions of pounds in a single season. On the 15th April 1872, Zanzibar was visited by a hurricane of extraordinary violence, by which about five-sixths of the clove-trees in the island were destroyed; and although the plantations are being renewed, many years must elapse before the crop can resume its former importance. Pemba, which is distant from Zanzibar 25 miles, and produced about half as much of the spice as that island, did not appreciably suffer from the storm.

The crop on these islands fluctuates, a good year alternating with a bad one. This is partly shown in the imports of Bombay, the great mart of Zanzibar produce, which have been as follows:—

1869-70 1870-71 1871-72 1872-73
45,642 cwt. 21,968 cwt. 43,891 cwt. 25,185 cwt.

The quantity of cloves shipped from Bombay to the United Kingdom is comparatively small, being in 1871-72, 3279 cwt.; in 1872-73, 3271 cwt.

The imports of cloves to the United Kingdom are from one million to four million pounds annually.

Cloves are also largely shipped direct from Zanzibar to the United States and Hamburg. A small amount is taken in native vessels to the Red Sea ports; these are packed in raw hides. Those for the European and American markets are shipped in mat bags made of split cocoa-nut leaf.

[1093] Gmelin, _Chemistry_, xiv. (1860) 201.

The clove trade of the Moluccas has been for many years in the hands of the Dutch Government, which, by its restrictive policy, assumed practically the position of growers, disposing of their produce through the Netherlands Trading Company at auctions held in Holland twice a year. This system having been abolished in 1872, has proved disastrous to the trade it was designed to protect, and to such a degree that the produce of cloves in the Moluccas is but a tenth of what it was in the early days of their intercourse with Europe. The crop of the four islands, Amboyna, Haruku, Saparua, and Nusalaut, the only Moluccas in which the tree is cultivated, was reckoned in 1854 as 510,912 lb.

The export of cloves from Java in 1871 was 1397 peculs[1094] (186,226 lb.). The French island of Réunion which from 1825 to 1849 used to produce annually as much as 800,000 kilogrammes (1,764,571 lb.), now yields almost none, owing chiefly to the frequent hurricanes.

=Uses=—As a remedy, cloves are unimportant, though in the form of infusion or distilled water they are useful in combination with other medicines. The essential oil which sometimes relieves toothache is a frequent ingredient of pill-masses. The chief consumption of cloves is as a culinary spice.

=Substitutes=—1. _Clove Stalks_—_Festucœlvel Stipites Caryophylli_, in French _Griffes de Girofle_, in German _Nelkenstiele_, were an article of import into Europe during the middle ages, when they were chiefly known by their low Latin name of _fusti_, or the Italian _bastaroni_. Thus under the statutes of Pisa,[1095] A.D. 1305, duty was levied not only on cloves (_garofali_), but also on _Folia et fusti garofalorum_. Pegolotti[1096] a little later names both as being articles of trade at Constantinople. Clove _Leaves_ are enumerated[1097] as an import into Palestine in the 12th century; they are also mentioned in a list of the drugs sold at Frankfort[1098] about the year 1450; we are not aware that they are used in modern times.

As to Clove Stalks, they are still a considerable object of trade, especially from Zanzibar, where they are called by the natives _Vikunia_. They taste tolerably aromatic, and yield 4 to 6·4 per cent. of volatile levogyre oil; they are used for adulterating the _Ground Cloves_ sold by grocers. Such an admixture may be detected by the microscope, especially if the powder after treatment with potash be examined in glycerin. If clove stalks have been ground, thick-walled or stone-cells will be found in the powder; such cells do not occur in cloves. Powdered allspice is also an adulterant of powdered cloves; it also contains stone-cells, but in addition numerous starch granules which are entirely wanting in cloves.

2. _Mother Cloves, Anthophylli_—are the _fruits_ of the clove-tree, and are ovate-oblong berries about an inch in length and much less rich in essential oil than cloves. Though occasionally seen in the London drug sales in some quantity, they are not an article of regular import.[1099] As they contain very large starch granules, their presence as an adulteration of ground cloves would be revealed by the microscope.

[1094] _Consular Reports_, Aug. 1873. 952.

[1095] Bonaini, _Statuti inediti della città di Pisa dal xii. al xiv. secolo_, iii. (1857) 106.

[1096] See p. 235, note 2.

[1097] _Recueil des Historiens des Croisades, Lois_, ii. (1843) 173.

[1098] Flückiger, _Die Frankfurter Liste_, Halle, 1873. 11. 38.

[1099] We find in the fortnightly price current of a London drug-broker under date Nov. 27, 1873, the announcement of the sale of 1,050 bags of Mother Cloves at 2_d._ to 3_d._ per lb., besides 4,200 packages of Clove Stalks at 3_d._ to 4_d._ per lb.

3. _=Royal Cloves=_—Under this name or _Caryophyllum regium_, a curious monstrosity of the clove was formerly held in the highest reputation, on account of its rarity and the strange stories told respecting it.[1100] Specimens in our possession show it to be a very small clove, distinguished by an abnormal number of sepals and large bracts at the base of the calyx-tube, the corolla and internal organs being imperfectly developed.

FRUCTUS PIMENTÆ.

_Semen Amomi_; _Pimento_, _Allspice_, _Jamaica Pepper_; F. _Poivre de la Jamaïque_, _Piment des Anglais_, _Toute-épice_; G. _Nelkenpfeffer_, _Nelkenköpfe_, _Neugewürz_.

=Botanical Origin=—_Pimenta officinalis_ Lindley[1101] (_Myrtus Pimenta_ L., _Eugenia Pimenta_ DC.), a beautiful evergreen tree, growing to about 30 feet in height, with a trunk 2 feet in circumference, common throughout the West India Islands. In Jamaica, it prefers limestone hills near the sea, and is especially plentiful on the north side of the island.

=History=—The high value placed on the spices of India sufficiently explains the interest with which aromatic and pungent plants were regarded by the early explorers of the New World; while the eager desire to obtain these lucrative commodities is shown by the names _Pepper_, _Cinnamon_, _Balsam_, _Melegueta_, _Amomum_, bestowed on productions totally distinct from those originally so designated.

Among the spices thus brought to the notice of Europe were the little dry berries of certain trees of the myrtle tribe, which had some resemblance in shape and flavour to peppercorns, and hence were named _Pimienta_,[1102] corrupted to _Pimenta_ or _Pimento_. It was doubtless a drug of this kind, if not our veritable allspice, that was given to Clusius in 1601 by Garret, a druggist of London, and described and figured by the former in his _Liber Exoticorum_.[1103] A few years later it began to be imported into England, being, as Parkinson[1104] says, “obtruded for _Amomum_” (_Round Cardamom_), so that “some more audacious than wise ... put it in their compositions instead of the right.” Francesco Redi mentioned the fruits as _Pimienta de Chapa_; Chiapas, now the south-eastern department of Mexico, bordering Guatemala. Redi states that the spice was also called _Pimienta de Tavasco_ from the adjoining department of Tabasco. According to Sloane[1105] (1691) it was commonly sold by druggists for _Carpobalsamum_. Ray (1693) distinguished the spice as a production of Jamaica under the name of _Sweet-scented Jamaica Pepper_ or _Allspice_, and states it to be abundantly imported into England, and in frequent use as a condiment, though not employed in medicine. The spice had a place in the London Pharmacopœia as early as 1721.

[1100] Rumphius in his letter from Amboina, Sept. 20, 1696, to Dr. Schröck, in _Ephemerides Acad. Cæs. Leopold. Decur._ iii. Frankfurt and Leipzig. 1700. p. 308, with figure.—Also Rumphius, _Herb. Amb._ ii. (1742) 11. tab. 2.—See also Hasskarl, _Neuer Schlüssel zu Rumph’s Herb. Amb._, Halle, 1866; Berg, _Linnæa_, 1854. 137; Valmont de Bomare, _Dict. d’Hist. Nat._ iii. (1775) 70.

[1101] Fig. in Bentley and Trimen, _Med. Plants_, part 20 (1877).

[1102] _Pimienta_, the Spanish for _pepper_, is derived from _pigmentum_, a general name in mediæval Latin for _spicery_.—_Malaguetta_ (see article Grana Paradisi) is also a name which has been transferred by the Spaniards and Portuguese to the drug under notice.

[1103] Lib. i. c. 17.

[1104] _Theatrum Botanicum_ (1640) 1567.

[1105] _Description of the Pimienta or Jamaica Pepper-tree._—_Phil. Trans._ xvii. No. 191.

The consumption of Pimento has been enormous. In the year 1804-5, the quantity shipped from the British West Indies was 2,257,000 lb., producing on import duty a net revenue of £38,063.[1106]

=Production and Commerce=—The spice found in commerce is furnished wholly by the island of Jamaica. A plantation, there called a _Pimento walk_, is a piece of natural woodland stocked with the trees, which require but little attention. The flowers appear in June, July, and August, and are quickly succeeded by the berries, which are gathered when of full size but still unripe. This is performed by breaking off the small twigs bearing the bunches. These are then spread out, and exposed to the sun and air for some days, after which the stalks are removed, and the berries are fit for being packed.

By an official document[1107] it appears that, in the year 1871, the amount of land in Jamaica cropped with pimento was 7,178 acres. In that year the island exported of the spice 6,857,838 lb., value £28,574. Of this quantity Great Britain took 4,287,551 lb., and the United States 2,266,950 lb. In 1875 the export was 57,500 cwts., valued at £40,250, of which 10,894 cwts. only went to the United States.

[1106] _Parliamentary Return_, March 1805, quoted in Young’s _West India Commonplace Book_, 1807. 79.

[1107] _Blue Book_ for Jamaica, printed 1872.

=Description=—Allspice is a small, dry globular berry, rather variable in size, measuring ³/₁₀ to less than ²/₁₀ of an inch in diameter. It is crowned by a short style, seated in a depression, and surrounded by 4 short thick sepals; generally however the latter have been rubbed off, a scar-like raised ring marking their former position. The berry has a woody shell or pericarp, easily cut, of a dark ferruginous brown, and rugose by reason of minute tubercles filled with essential oil. It is two-celled, each cell containing a single, reniform, exalbuminous seed, having a large spirally curved embryo. The seed is aromatic, but less so than the pericarp.

Allspice has an agreeable, pungent, spicy flavour, much resembling that of cloves.

=Microscopic Structure=—The outer layer of the pericarp, immediately beneath the epidermis, contains numerous large cells filled with essential oil. The parenchyme further exhibits thick-walled cells loaded with resin, and smaller cells enclosing crystals of oxalate of calcium. The whole tissue is traversed by small fibro-vascular bundles. The seeds are also provided with a small number of oil-cells, and contain starch granules.

=Chemical Composition=—The composition of pimento resembles in many points that of cloves. The berries yield to the extent of 3 to 4½ per cent. a volatile oil, sp. gr. 1·037 (Gladstone), having the characteristic taste and odour of the spice, and known in the shops as _Oleum Pimentæ_. We have found it to deviate the ray of polarized light 2° to the left, when examined in a column of 50 mm.

Oeser (1864), whose experiments have been confirmed by Gladstone (1872), has shown that oil of pimento has substantially the same composition as oil of cloves; salicylic acid has not been found. Pimento is rich in tannin, striking with a persalt of iron an inky black. Its decoction is coloured deep blue by iodine, showing the presence of starch. Dragendorff (1871) pointed out the existence in allspice of an extremely small quantity of an alkaloid, having somewhat the odour of coniine.

=Uses=—Employed as an aromatic clove; a distilled water (_Aqua Pimentæ_) is frequently prescribed. The chief use of pimento is as a culinary spice.

=Substitute=—The Mexican spice called _Pimienta de Tabasco_ (_Piment Tabago_ Guibourt) is somewhat larger and less aromatic than Jamaica allspice. Analogous products are afforded by _Pimenta acris_ Wight[1108] (_Myrcia acris_ DC, _Amomis acris_ Berg), the _Bay-berry_ tree, and _P. Pimento_ Griseb. The oil of bay-berry consists of eugenol and a hydrocarbon, possibly identical with the “light oil of cloves” (p. 284), but present in a larger amount. _Bay rum_, much used in the United States by the perfumers, is an alcoholic tincture flavoured with oil of bay-berry.

GRANATEÆ.

CORTEX GRANATI FRUCTUS.

_Cortex Granati_; _Pomegranate Peel_; F. _Ecorce de Grenades_; G. _Granatschalen_.

=Botanical Origin=—_Punica Granatum_ L., a shrub or low tree, with small deciduous foliage and handsome scarlet flowers. It is indigenous to North-western India, and the counties south and south-west of the Caspian to the Persian Gulf and Palestine, and grows wild in the hills of Western Sindh in elevations of 4000 feet, in Balutchistan to 6000 feet, also in the east flank of Soliman range. The trunk is short, rarely over 20 feet high. The tree has long been cultivated, and is now found throughout the warm parts of Europe, and in the subtropical regions of both hemispheres.

=History=—The pomegranate has been highly prized by mankind from the remotest antiquity, as is shown by the references to it in the Scriptures,[1109] and by the numerous representations of the fruit in the sculptures of Persepolis and Assyria,[1110] and on the ancient monuments of Egypt.[1111] It was probably introduced into the south of Italy by Greek colonists, and is named as a common fruit-tree by Porcius Cato[1112] in the 3rd century B.C. The peel of the fruit was recognized as medicinal by the ancients, and among the Romans was in common use for tanning leather,[1113] as it still is in Tunis.

[1108] Figured in Bentley and Trimen, part 20.—The fruit of this species is easily distinguished, being crowned by 5-calyx lobes.

[1109] _Exodus_ xxviii. 33, 34; _Numbers_ xx. 2; _Deut._ viii 8; _Cant._ iv. 13; viii. 2.

[1110] Layard, _Nineveh and its Remains_, ed. 5, ii. (1849) 296.

[1111] Wilkinson, _Ancient Egyptians_, ii. (1837) 142.

[1112] Nisard’s edition, Paris, 1877, capp. 7. 127. 133.

[1113] See also Hehn, _Kulturpflanzen_, Berlin, 1877, 206.

=Description=—The fruit of the pomegranate tree is a spherical, somewhat flattened and obscurely six-sided berry, the size of a common orange and often much larger, crowned by the thick, tubular, 5-to 9-toothed calyx. It has a smooth, hard, coriaceous skin, which when the fruit is ripe, is of a brownish yellow tint, often finely shaded with red. Membranous dissepiments, about 6 in number meeting in the axis of the fruit, divide the upper and larger portion into equal cells. Below these a confused conical diaphragm separates the lower and smaller half, which in its turn is divided into 4 or 5 irregular cells. Each cell is filled with a large number of grains, crowded on thick spongy placentæ, which in the upper cells are parietal but in the lower appear to be central. The grains, which are about ½ an inch in length, are oblong or obconical and many-sided, and consist of a thin transparent vesicle containing an acid, saccharine, red, juicy pulp, surrounding an elongated angular seed.

The only part of the fruit used medicinally is the peel, _Cortex Granati_ of the druggists, which in the fresh state is leathery. When dry as imported, it is in irregular, more or less concave fragments, some of which have the toothed, tubular calyx still enclosing the stamens and style. It is ⅒ to ¹/₂₀ of an inch thick, easily breaking with a short corky fracture; externally it is rather rough, of a yellowish-brown or reddish colour. Internally it is more or less brown or yellow, and honey-combed with depressions left by the seeds. It has hardly any odour, but has a strongly astringent taste.

=Microscopic Structure=—The middle layer of the peel consists of large thin-walled and elongated, sometimes even branched cells, among which occur thick-walled cells and fibro-vascular bundles. Both the outer and the inner surface are made up of smaller, nearly cubic and densely packed cells. Small starch granules occur sparingly throughout the tissue, as well as crystals of oxalate of calcium.

=Chemical Composition=—The chief constituent is tannin, which in an aqueous infusion of the dried peel produces with perchloride of iron an abundant dark blue precipitate. The peel also contains sugar and a little gum. Dried at 100° C. and incinerated, it yielded us 5·9 per cent. of ash.

=Uses=—Pomegranate peel is an excellent astringent, now almost obsolete in British medicine. Waring[1114] asserts that when combined with opium and an aromatic, as cloves, it is a most useful remedy in the chronic dysentery of the natives of India, as well as in diarrhœa.

[1114] _Pharm. of India_, 1868. 93. 447.

CORTEX GRANATI RADICIS.

_Pomegranate-root Bark_; F. _Ecorce de racine de Grenadier_; G. _Granatwurzelrinde_.

=Botanical Origin=—_Punica Granatum_ L., see page 289.

=History=—In addition to the particulars regarding the pomegranate tree given in the preceding article, the following which concern the drug under notice may be stated.

A decoction of the root of the pomegranate was recommended by Celsus,[1115] Dioscorides,[1116] and Pliny[1117] for the expulsion of tapeworm; but the remedy had fallen into complete oblivion, until its use among the Hindus attracted the notice of Buchanan[1118] at Calcutta about the year 1805. This physician pointed out the efficacy of the root-bark, which was further shown by Fleming and others. Pomegranate-root is known to have been long used for a similar purpose by the Chinese.[1119]

Though the medicine is admitted to be efficient, and is employed with advantage in India where it is easily procured both genuine and fresh, it is hardly ever administered in England, the extract of male-fern being generally preferred; but it has a place in several continental pharmacopœias.

=Description=—The bark occurs in rather thin quills or fragments, 3 to 4 inches long. Their outer surface is yellowish-grey, sometimes marked with fine longitudinal striations or reticulated wrinkles, but more often furrowed by bands of cork, running together in the thickest pieces into broad flat conchoidal scales. The inner surface, which is smooth or marked with fine striæ and is of a greyish yellow, has often strips of the tough whitish wood attached to it. The bark breaks short and granular; it has a purely astringent taste, but scarcely any odour.

=Microscopic Structure=—On a transverse section, the liber is seen to be the prevailing part of the cortical tissue. The former consists of alternating layers of two kinds of cells—one of them loaded with tufted crystals of oxalate of calcium, the other filled with starch granules and tannic matter. The bark is traversed by narrow medullary rays, and very large sclerenchymatous cells are scattered through the liber. Touched with a dilute solution of a persalt of iron, the bark assumes a dark blackish blue tint.

=Chemical Composition=—The bark contains, according to Wackenroder (1824), more than 22 per cent. of tannic acid, which Rembold (1867) has ascertained to consist for the most part of a peculiar variety called _Punico-tannic Acid_, C₂₀H₁₆O₁₃; when boiled with dilute sulphuric acid, it is resolved into _Ellagic Acid_, C₁₄H₈O₉, and sugar. Punico-tannic acid is accompanied by common tannic acid, yielding, by means of sulphuric acid, gallic acid, which appears sometimes to pre-exist in the bark. If a decoction of pomegranate bark is precipitated by acetate of lead, and the lead is separated from the filtered liquid, the latter on evaporation yields a considerable amount of mannite. This is probably the _Punicin_ or _Granatin_ of former observers.

[1115] _De Medicina_, lib. iv. c. 17.

[1116] Lib. i. c. 153.

[1117] Lib. xxiii. c. 60.

[1118] _Edinb. Med. and Surg. Journ._, iii. (1807) 22.

[1119] Debeaux, _Pharmacie et Mat. Méd. des Chinois_, 1865. 70.

The tænicide power is due, according to Tanret (1878) to _Pelletierine_, C₈H₁₅NO, a liquid dextrogyre alkaloid, boiling at 180° to 185° C. It can be obtained colourless by evaporating its ethereal solution in a vacuum, but in the open air becomes yellow. Pelletierine, so called in honour of Pelletier, is readily soluble in water, alcohol or chloroform, and has a somewhat aromatic odour. Several of its salts are crystallizable, yet extremely hygroscopic. The yield of the root-bark was about ½ per cent. of the alkaloid, or about 2 per cent. of crystallized sulphate from trees grown near Troyes, in the Champagne.

=Uses=—A decoction, followed by a purgative, is stated by Waring[1120] and others to be most efficient for the expulsion of the tapeworm. The _fresh_ bark is said to be preferable to the dried.

=Adulterations=—The commercial drug frequently consists partly or entirely of the bark of the stem or branches, characterized by its less abundant cork-formation, which exhibits longitudinal bands or ridges of light brownish cork, but not conchoidal exfoliations. The middle cortical layer is somewhat more developed, and contains in the outer cells deposits of chlorophyll. The cambial zone is not distinctly observable. Such bark is reputed to be less active than that of the root, but we are not aware that the fact has ever been proved.

The bark of _Buxus sempervirens_ and of _Berberis vulgaris_ are somewhat similar to the drug under notice, but their decoctions are not affected by salts of iron.

CUCURBITACEÆ.

FRUCTUS ECBALLII.

_Fructus Elaterii_; _Elaterium Fruit_, _Squirting Cucumber_, _Wild Cucumber_; F. _Concombre purgatif ou sauvage_; G. _Springgurke_.

=Botanical Origin=—_Ecballium[1121] Elaterium_ A. Richard (_Momordica Elaterium_ L.), a coarse, hispid, fleshy, decumbent plant without tendrils, having a thick white perennial root. It is common throughout the Mediterranean region, extending eastward as far as Southern Russia and Persia, and westward to Portugal. It succeeds well in Central Europe, and is cultivated to a small extent for medicinal use at Mitcham and Hitchin in England.

=History=—Theophrastus mentions the plant under notice by the name of Σίκυος ἄγριος. It is also particularly noticed by Dioscorides, who explicitly describes the singular process for making elaterium (ἐλατήριον), which was almost exactly like that followed at the present day.

The Wild or Squirting Cucumber was well known and cultivated in gardens in England as early as the middle of the 16th century.[1122]

[1120] _Indian Annals of Med. Science_, vi. (1859); _Pharmacopœia of India_, 1868. 93.

[1121] _Ecballium_ from ἐκβάλλω, I expel, in allusion to the expulsion of the seeds: often erroneously written _Ecbalium_.

[1122] Turner’s _Herball_, 1568, part i. 180.

=Description=—The fruit is ovoid-oblong, nodding, about 1½ inch long, hispid from numerous short fleshy prickles terminating in white elongated points. It is attached by a long scabrous peduncle, is fleshy and green while young, becoming slightly yellowish when mature; it is 3-celled and contains numerous oblong seeds lodged in a very bitter succulent pulp. The fruit when ripe separates suddenly from the stalk, and at the same moment the seeds and juice are forcibly expelled from the aperture left by the detached peduncle. This interesting phenomenon[1123] is due to the process of exosmosis, by which the juice of the outer part of the fruit gradually passes through the strong contractile tissue which lines the central cavity, until the pressure becomes so great that the cell gives way at its weakest point. This point is that at which the peduncle is articulated with the fruit; and it is the sudden and powerful contraction of the elastic tissue when relieved from pressure that occasions the violent expulsion of the contents of the central cavity.

For the preparation of the officinal elaterium, the fruit has to be employed while still somewhat immature, for the simple reason that it would be impossible to gather it so as to retain its all-important juice if left till quite ripe. When it is sliced longitudinally as in making elaterium, some of the juice is expelled by virtue of the endosmotic action already described, as can easily be seen on examining the contracted lining of the sliced fruit.

Pereira observes[1124] that if the juice of a fruit is received on a plate of glass, it is seen to be nearly colourless and transparent. In a few minutes however, by exposure to the air, it becomes slightly turbid, and small white coagula are formed in it. By slow evaporation, minute rhomboidal crystals make their appearance: these are _elaterin_.

Hot, dry weather favours the development of the active principle of the drug.[1125]

=Microscopic Structure=—The middle layer of the fruit is built up of large somewhat thick-walled cells, traversed by a few fibro-vascular bundles. The former abound in small starch grains, and also contain granules of albuminous matter.

=Chemical Composition=—The experiments of Clutterbuck (1819) proved that the active properties of the elaterium plant reside chiefly, though not exclusively, in the juice that surrounds the seeds; and it is to this juice and to the medicinal product which it yields, that the attention of chemists has been hitherto directed.

The juice obtained by lightly pressing the sliced fruits is at first greenish and slightly turbid. After having been set aside a few hours, it yields a deposit, which has to be collected on calico, rapidly drained with gentle pressure between layers of bibulous paper and porous bricks, and dried in a warm place. The substance thus obtained is the _Elaterium_ of pharmacy.[1126] The method recommended by Clutterbuck[1127] involves no pressing. The juice of the sliced fruit is saved, and the pulp, scooped out by the thumb of the operator, is thrown on a sieve and slightly washed with pure water. From these liquors, elaterium is deposited.

[1123] I have not yet seen Yule’s paper on the dehiscence of this fruit in the _Journ. of Anat. and Physiology_, 1877. The structure of the testa of the seed is explained by Fickel, in the _Botanische Zeitung_, 1876. 774.—F. A. F..

[1124] _Elem. of Mat. Med._ ii. (1853) 1745.

[1125] Having had to procure elaterium fruits at Mitcham in the very fine summer of 1868, I was told that the people occupied in slicing the fruits had never suffered so severely from their work as in that year.—D. H.

[1126] There is a genus of _Cucurbitaceæ_ founded by Linnæus, also called _Elaterium_.

[1127] _Lond. Med. Repository_, xii. (1820) 1.

Elaterium occurs in irregular cake-like fragments, light, friable, and opaque; when new, of a bright pale green, becoming by age greyish and exhibiting minute crystals on the surface. It has a herby tea-like odour and a very bitter taste. The produce is extremely small: 240 lb. of fruit gathered at Mitcham, 1Oth August 1868, yielded 4⅝ ounces of elaterium = 0·123 per cent.