BURSERACEÆ.

OLIBANUM.

Gummmi-resina Olibanum, Thus masculum[520]; Olibanum, Frankincense; F. Encens; G.Weihrauch.

Botanical Origin—Olibanum is obtained from the stem of several species of Boswellia, inhabiting the hot and arid regions of Eastern Africa, near Cape Gardafui and of the southern coast of Arabia. Notwithstanding the recent elaborate and valuable researches of Birdwood,[521] the olibanum trees are still but imperfectly known, as will be evident in the following enumeration:—

1. Boswellia Carterii Birdw.—This includes the three following forms, which may be varieties of a single species, or may belong to two or more species,—a point impossible to settle until more perfect materials shall have been obtained.

a. Boswellia No. 5, Oliver, Flora of Tropical Africa, I. (1868) 324, Mohr meddu or Mohr madow of the natives; meddu, according to Playfair and Hildebrandt, means black. The leaflets are crenate, undulate, and pubescent on both sides.

This tree is found in the Somali Country, growing a little inland in the valleys and on the lower part of the hills, never on the range close to the sea. It yields the olibanum called Lubân Bedowi or Lubân Sheheri (Playfair).

Hildebrandt describes the Mohr meddu as a tree 12 to 15 feet high, with a few branches, indigenous to the limestone range of Ahl or Serrut, in the northern part of the Somali Country, where it occurs in elevations of from 3000 to 5000 feet. To this tree belongs the figure 58 in Bentley and Trimen’s Medicinal Plants (Part 20, 1877).

b. Boswellia No. 6, Oliver, op. cit., Birdwood, Linn. Trans. xxvii., tab. 29.—Sent by Playfair among the specimens of the preceding, and with the same indications and native name. This form, the “Mohr meddu” of the Somalis, has obscurely serrulate or almost entire leaflets, velvety and paler below, glabrous above. The figure (which is not given in the reprint) is very much the same as that of the following.

c. Maghrayt d’sheehaz of the Maharas, Birdwood, l. c. tab. 30, reprinted in Cooke’s report, plate I; Carter, Journ. of Bombay Branch of R. Asiat. Soc. ii., tab. 23; B. sacra Flückiger, Lehrbuch der Pharmakognosie des Pflanzenreiches, 1867. 31.—Ras Fartak, S.E. coast of Arabia, growing in the detritus of limestone cliffs and close to the shore,[522] also near the village of Merbat (Carter, 1844-1846).

Birdwood’s figure refers to a specimen propagated in the Victoria Gardens, Bombay, from cuttings sent there from the Somali country by Playfair.

2. B. Bhau-Dajiana Birdw. l. c. tab. 31, or plate III. of the reprint.—Somali Country (Playfair); cultivated in Victoria Gardens, Bombay, where it flowered in 1868. The differences between this species and B. Carterii are not very obvious.

3. Boswellia No. 4, Oliver, op. cit.—Bunder Murayah, Somali Country (Playfair). Grows out of the rock, but sometimes in the detritus of limestone; never found on the hills close to the sea, but further inland and on the highest ground. Yields Lubân Bedowi and L. Sheheri; was received at Kew as Mohr add, a name applied by Birdwood also to B. Bhau-Dajiana.

From the informations due to Captains Miles[523] and Hunter and to Haggenmacher[524] it would appear that the Beyo or Beyu of the Somalis (Boido, Capt. Hunter) is agreeing with this tree.

4. Boswellia neglecta, S. Le M. Moore, in Journ. of Botany, xv.(1877) 67 and tab. 185. This tree has been collected by Hildebrandt in the limestone range, Ahl or Serrut, in the northern part of the Somali Country. It occurs in elevations of 1000 to 1800 metres, and attains a height of 5 to 6 metres. Its exudation, according to Hildebrandt, is collected in but small quantity and mixed with the other kinds of olibanum. Moore gives Murlo as the vernacular name of this tree, Hildebrandt calls it Mohr add.

In addition to the foregoing, from which the olibanum of commerce is collected, it may be convenient to mention also the following:—

1. Boswellia Frereana Birdw., a well-marked and very distinct species of the Somali Country, which the natives call Yegaar. It abounds in a highly fragrant resin collected and sold as Lubân Meyeti or Lubân Mati, which we regard to be the substance originally known as Elemi (see this article).

2. B. papyrifera Richard (Plösslea floribunda Endl.), the “Makar” of Sennaar and the mountainous region ascending to 4000 feet above the level of the sea on the Abyssinian rivers Takazze and Mareb. It appears not to grow in the outer parts of north-eastern Africa. Its resin is not collected, and stated by Richard[525] to be transparent; it consists no doubt merely of resin (and essential oil?) without gum.[526]

3. B. thurifera Colebr. (B. glabra et B. serrata Roxb.), the Salai tree of India, produces a soft odoriferous resin which is used in the country as incense but is not the olibanum of commerce. The tree is particularly abundant on the trap hills of the Dekhan and Satpura range. Berg, in “Offizinelle Gewächse,” xiv. c. gives a good figure of this species.

History—The use of olibanum goes back to a period of extreme antiquity, as proved by the numerous references[527] in the writings of the Bible to incense, of which it was an essential ingredient. It is moreover well known that many centuries before Christ, the drug was one of the most important objects of the traffic which the Phœnicians[528] and Egyptians carried on with Arabia.

Professor Dümichen[529] of Strassburg has discovered at the temple of Dayr el Báhri in Upper Egypt, paintings illustrating the traffic carried on between Egypt and a distant country called Punt or Pount as early as the 17th century b.c. In these paintings there are representations not only of bags of olibanum, but also of olibanum trees planted in tubs or boxes, being conveyed by ship from Arabia to Egypt. Inscriptions on the same building, deciphered by Professor D., describe with the utmost admiration the shipments of precious woods, heaps of incense, verdant incense trees,[530] ivory, gold, stimmi (sulphide of antimony), silver, apes, besides other productions not yet identified. The country Pount was first thought to be southern Arabia, but is now considered to comprehend the Somali coast, together with a portion of the opposite Arabian coast. Punt possibly refers to “Opone,” an old name for Hafoon, a place south of Cape Gardafui.

A detailed account of frankincense is given by Theophrastus[531] (b.c. 370-285) who relates that the commodity is produced in the country of the Sabæans, one of the most active trading nations of antiquity, occupying the southern shores of Arabia. It appears from Diodorus that the Sabæans sold their frankincense to the Arabs, through whose hands it passed to the Phœnicians who disseminated the use of it in the temples throughout their possessions, as well as among the nations with whom they traded. The route of the caravans from south-eastern Arabia to Gaza in Palestine, has recently (1866) been pointed out by Professor Sprenger. Plutarch relates that when Alexander the Great captured Gaza, 500 talents of olibanum and 100 talents of myrrh were taken, and sent thence to Macedonia.

The libanotophorous region of the old Sabæans is in fact the very country visited by Carter in 1844 and 1846, and lying as he states on the south coast of Arabia between long. 52° 47′ and 52° 23′ east.[532] It was also known to the ancients, at least to Strabo and Arrian, that the opposite African coast likewise produced olibanum,[533] as it is now doing almost exclusively; and the latter states that the drug is shipped partly to Egypt and partly to Barbaricon at the mouth of the Indus.

As exemplifying the great esteem in which frankincense was held by the ancients, the memorable gifts presented by the Magi to the infant Saviour will occur to every mind. A few other instances may be mentioned: Herodotus[534] relates that the Arabians paid to Darius, king of Persia, an annual tribute of 1000 talents of frankincense.

A remarkable Greek inscription, brought to light in modern times[535] on the ruins of the temple of Apollo at Miletus, records the gifts made to the shrine by Seleucus II., king of Syria (b.c. 246-227), and his brother Antiochus Hierax, king of Cilicia, which included in addition two vessels of gold and silver, ten talents of frankincense (λιβανωτοός) and one of myrrh.

The emperor Constantine made numerous offerings to the church under St. Silvester, bishop of Rome a.d. 314-335, of costly vessels and fragrant drugs and spices,[536] among which mention is made in several instances of Aromata and Aromata in incensum, terms under which olibanum is to be understood.[537]

With regard to the consumption of olibanum in other countries, it is an interesting fact that the Arabs in their intercourse with the Chinese, which is known to have existed as early as the 1Oth century, carried with them olibanum, myrrh, dragon’s blood, and liquid storax,[538] drugs which are still imported from the west into China. The first-named is called Ju-siang, i.e. milk perfume, a curious allusion to its Arabic name Lubân signifying milk. In the year 1872, Shanghai imported[539] of this drug no less than 1,360 peculs (181,333 lb.).

Collection—The fragrant gum-resin is distributed through the leaves and bark of the trees, and even exudes as a milky juice also from the flowers; its fragrance is stated to be already appreciable in a certain distance. Cruttenden,[540] who visited the Somali Country in 1843, thus describes the collecting of olibanum by the Mijjertheyn tribe, whose chief port is Bunder Murayah (lat. 11° 43′ N.)[541]:—

“During the hot season the men and boys are daily employed in collecting gums, which process is carried on as follows:—About the end of February or beginning of March, the Bedouins visit all the trees in succession and make a deep incision in each, peeling off a narrow strip of bark for about 5 inches below the wound. This is left for a month when a fresh incision is made in the same place, but deeper. A third month elapses and the operation is again repeated, after which the gum is supposed to have attained a proper degree of consistency. The mountain sides are immediately covered with parties of men and boys, who scrape off the large clear globules into a basket, whilst the inferior quality that has run down the tree is packed separately. The gum when first taken from the tree is very soft, but hardens quickly.... Every fortnight the mountains are visited in this manner, the trees producing larger quantities as the season advances, until the middle of September, when the first shower of rain puts a close to the gathering that year.”

The informations due to J. M. Hildebrandt, who visited the Somali in 1875, are in accordance with Cruttenden’s statements. The former says, that the latest crops are greatly injured by the rains, the drug being partly dissolved by the water.

Carter[542] describing the collection of the drug in southern Arabia, writes thus:—“The gum is procured by making longitudinal incisions through the bark in the months of May and December, when the cuticle glistens with intumescence from the distended state of the parts beneath; the operation is simple, and requires no skill on the part of the operator. On its first appearance the gum comes forth white as milk, and according to its degree of fluidity, finds its way to the ground, or concretes on the branch near the place from which it first issued, from whence it is collected by men and boys employed to look after the trees by the different families who possess the land in which they grow.” According to Captain Miles,[543] the drug is not collected by the people of the country, but by Somalis who cross in numbers from the opposite coast, paying the Arab tribes for the privilege. The Arabian Lubân, he says, is considered inferior to the African.

It would even appear that the collection of the drug has ceased in Arabia, and that the names of Lubân Maheri or Mascati or Sheehaz, referring to the coast of Arabia between Ras Fartak (52° 10′ E.) and Ras Morbas (54° 34′) are now applied to the olibanum brought there from the opposite African coast.[544] Hildebrandt informed one of us (letter dated 26th Dec., 1878) that he has ascertained at Aden, that all the frankincense imported in Aden comes from Africa.

Description—Olibanum as found in commerce varies rather considerably in quality and appearance. It may in general terms be described as a dry gum-resin, consisting of detached tears up to an inch in length, of globular, pear-shaped, clavate, or stalactitic form, mixed with more or less irregular lumps of the same size. Some of the longer tears are slightly agglutinated, but most are distinct. The predominant forms are rounded,—angular fragments being less frequent, though the tears are not seldom fissured. Small pieces of the translucent brown papery bark are often found adhering to the flat pieces. The “Lubân Fasous Bedow” as exported from the Mijjertheyn district, in the eastern part of the Somali Country, is in very fine large tears.

The colour of the drug is pale yellowish or brownish, but the finer qualities consist of tears which are nearly colourless or have a greenish hue. The smallest grains only are transparent, the rest are translucent and somewhat milky, and not transparent even after the removal of the white dust with which they are always covered. But if heated to about 94° C., they become almost transparent. When broken they exhibit a rather dull and waxy surface. Examined under the polarizing microscope no trace of crystallization is observable.

Olibanum softens in the mouth; its taste is terebinthinous and slightly bitter, but by no means disagreeable. Its odour is pleasantly aromatic, but is only fully developed when the gum-resin is exposed to an elevated temperature. At 100° C. the latter softens without actually fusing, and if the heat be further raised decomposition begins.

Chemical Composition—Cold water quickly changes olibanum into a soft whitish pulp, which when rubbed down in a mortar forms an emulsion. Immersed in spirit of wine, a tear of olibanum is not altered much in form, but it becomes of an almost pure opaque white. In the first case the water dissolves the gum, while in the second the alcohol removes the resin. We find that pure olibanum treated with spirit of wine leaves 27 to 35 of gum,[545] which forms a thick mucilage with three parts of water. Dissolved in 5 parts of water it yields a neutral solution, which is precipitated by perchloride of iron as well as by silicate of sodium, but not by neutral acetate of lead. It is consequently a gum of the same class as gum arabic, if not identical with it. Its solution contains the same amount of lime as gum arabic affords.

The resin of olibanum has been examined by Hlasiwetz (1867), according to whom it is a uniform substance having the composition C₂₀H₃₀O₃. We find that it is not soluble in alkalis, nor have we succeeded in converting it into a crystalline body by the action of dilute alcohol. It is not uniformly distributed throughout the tears; if they are broken after having been acted upon by dilute alcohol, it now and then happens that a clear stratification is perceptible, showing a concentric arrangement.

Olibanum contains an essential oil, of which Braconnot (1808) obtained 5 per cent., Stenhouse (1840) 4 per cent., and Kurbatow (1871-1874) 7 per cent. According to Stenhouse it has a sp. gr. of 0·866, a boiling point of 179·4° C., and an odour resembling that of turpentine but more agreeable. Kurbatow separated this oil into two portions, the one of which has the formula C₁₀H₁₆, boils at 158° C., and combines with HCl to form crystals; the other contains oxygen. The bitter principle of olibanum forms an amorphous brown mass.

The resin of olibanum submitted to destructive distillation affords no umbelliferone. Heated with strong nitric acid it develops no peculiar colour, but at length camphretic acid (see Camphor) is formed, which may be also obtained from many resins and essential oils if submitted to the same oxidizing agent.

Commerce—The olibanum of Arabia is shipped from several small places along the coast between Damkote and Al Kammar, but the quantity produced in this district is much below that furnished by the Somali Country in Eastern Africa. The latter is brought to Zeyla, Berbera, Bunder Murayah, and many smaller ports, whence it is shipped to Aden or direct to Bombay. The trade is chiefly in the hands of Banians, and the great emporium for the drug is Bombay. A certain portion is shipped through the straits of Bab-el-Mandeb to Jidda,—Von Kremer[546] says to the value of £12,000 annually. The quantity exported from Bombay in the year 1872-73 was 25,100 cwt., of which 17,446 cwt. were shipped to the United Kingdom, and 6,184 cwt. to China.[547]

Uses—As a medicine olibanum is nearly obsolete, at least in Britain. The great consumption of the drug is for the incense used in the Roman Catholic and Greek Churches.

MYRRHA.

Gummi-resina Myrrha; Myrrh; F. Myrrhe; G. Myrrhe.

Botanical Origin—Ehrenberg who visited Egypt, Nubia, Abyssinia, and Arabia in the years 1820-26, brought home with him specimens of the myrrh trees found at Ghizan (Gison or Dhizân), a town on the strip of coast-region called Tihâma, opposite the islands of Farsan Kebir and Farsan Seghir, and a little to the north of Lohaia, on the eastern side of the Red Sea, in latitude 16° 40′, and also on the neighbouring mountains of Djara (or Shahra) and Kara. Here the myrrh trees form the underwood of the forests of Acacia, Moringa, and Euphorbia. Nees von Esenbeck who examined these specimens, drew up from them a description of what he called Balsamodendron Myrrha, which he figured in 1828.[548]

After Ehrenberg’s herbarium had been incorporated in the Royal Herbarium of Berlin, Berg examined these specimens, and came to the conclusion that they consist of two species, namely that described and figured by Nees, and a second to which was attached (correctly we must hope) two memoranda bearing the following words:—“Ipsa Myrrhæ arbor ad Gison,—Martio,” and “Ex huic simillima arbore ad Gison ipse Myrrham effluentem legi.[549] Hæc specimina lecta sunt in montibus Djara et Kara Februario.” This plant Berg named B. Ehrenbergianum.[550] Oliver in his Flora of Tropical Africa (1868)[551] is disposed to consider Berg’s plant the same as B. Opobalsamun Kth., a tree or shrub yielding myrrh, found by Schweinfurth on the Bisharrin mountains in Abyssinia, not far from the coast between Suakin and Edineb. But Schweinfurth himself does not admit the identity of the two plants.[552] It is certain, however, that the myrrh of commerce is chiefly of African origin.

Captain F. M. Hunter, Assistant Resident of Aden, informed us[553] that the Arabian myrrh tree, the Didthin, is found not only in the southern provinces of Arabia, Yemen, and Hadramant, probably also in the southern part of Oman, but likewise on the range of hills which, on the African shore, runs parallel to the Somali coast. The Somalis who gather the myrrh in Arabia allege that the Arabian “Didthin” is identical with that of their own district. Its exudation is the true myrrh, “Mulmul” of the Somalis, the “Mur” of the Arabs, or “Heerabole[554] of the Indians.

Another myrrh tree, according to Captain Hunter, is growing in Ogadain and the districts round Harrar, that is between the 7th and 10th parallels, N. lat., and 43° to 50° E. long. This is the “Habaghadi” of the Somalis, which is not found in Arabia, nor in the coast range of the Somali country, but only at a considerable distance from the sea-shore. Its exudation is the coarse myrrh, habaghadi of the Somalis and Arabs and “Baisabole” of the Indians.

Hildebrandt has collected the didthin, or didin as he writes, in the coast range alluded to, that is in the Ahl or Serrut Mountains, where the tree is growing on sunny slopes in elevations of 500 to 1,500 metres. He has ascertained that it is identical with Ehrenberg’s tree, Balsamodendron Myrrha Nees. It is a low tree of crippled appearance, attaining not more than 3 metres. This species must therefore be pointed out as the source of true myrrh of the European commerce.

History—(See also further on, Bissabol). Myrrh has been used from the earliest times together with olibanum as a constituent of incense,[555] perfumes, and unguents. It was an ingredient of the holy oil used in the Jewish ceremonial as laid down by Moses: and it was also one of the numerous components of the celebrated Kyphi of the Egyptians, a preparation used in fumigations, medicine, and the process of embalming, and of which there were several varieties.

In the previous article we have pointed out (p. 137) several early references to myrrh in connection with olibanum, in which it is observable that the myrrh (when weights are mentioned) is always in the smaller quantity. Of the use of the drug in mediæval Europe there are few notices, but they tend to show that the commodity was rare and precious. This myrrh is recommended in the Anglo-Saxon Leech-books[556] to be used with frankincense in the superstitious medical practice of the 11th century. In a manuscript of the Monastery of Rheinau, near Schaffhausen, Switzerland, we also find that, apparently in the 11th century, myrrh as well as olibanum were used in ordeals in the “judicium aquæ bullientis.”[557] The drug was also used by the Welsh “Physicians of Myddfai” in the 13th century. In the Wardrobe accounts of Edward I. there is an entry under date 6th January, 1299, for gold, frankincense, and myrrh, offered by the king in his chapel on that day, it being the Feast of Epiphany.[558] Myrrh again figures in the accounts of Geoffroi de Fleuri,[559] master of the wardrobe (argentier) to Philippe le Long, king of France, where record is made of the purchase of—“4 onces d’estorat calmite” (see Styrax) “et mierre (myrrh) ... encenz et laudanon,” (Ladanum, the resin of Cistus creticus L.)—for the funeral of John, posthumous son of Louis X., a.d. 1316.

Gold, silver, silk, precious stones, pearls, camphor, musk, myrrh, and spices are enumerated[560] as the presents which the Khan of Cathay sent to Pope Benedict XII. at Avignon about the year 1342. The myrrh destined for this circuitous route to Europe[561] was doubtless that of the Arabian traders, with whom the Chinese had constant intercourse during the middle ages. Myrrh in fact is still somewhat largely consumed in China.[562]

The name Myrrh is from the Hebrew and Arabic Mur, meaning bitter, whence also the Greek σμύρνα. The ancient Egyptian Bola or Bal, and the Sanskrit Vola are preserved in the Persian and Indian words Bol, Bola, and Heerabol, well-known names for myrrh.

Stacte (στακτὴ), a substance often mentioned by the ancients, is said by Pliny to be a spontaneous liquid exudation of the myrrh tree, more valuable than myrrh itself. The author of the Periplus of the Erythrean Sea represents it as exported from Muza in Arabia[563] together with myrrh. Theophrastus[564] a.d. 314-335.[565]

The myrrh of the ancients was not always obtained from Arabia. The author of the Periplus,[566] who wrote about a.d. 64, records it to have been an export of Abalites, Malao, and Mosyllon (the last named the modern Berbera), ancient ports of the African coast outside the straits of Bab-el-Mandeb; and he even mentions that it is conveyed by small vessels to the opposite shores of Arabia.

Secretion—Marchand[567] who examined and figured the sections of a branch of three years’ growth of B. Myrrha, represents the gum-resin as chiefly deposited in the cortical layers, with a little in the medulla.

Collection—By the Somal tribe myrrh is largely collected as it flows out, incisions, according to Hildebrandt, being never practised. From the information given by Ehrenberg to Nees von Esenbeck,[568] it appears that myrrh when it first exudes is of an oily and then of a buttery appearance, yellowish white, gradually assuming a golden tint and becoming reddish as it hardens. It exudes from the bark like cherry-tree gum, and becomes dark and of inferior value by age. Although Ehrenberg says that the myrrh he saw was of fine quality, he does not mention it being gathered by the natives.

With regard to the localities[569] in which the drug is collected, Cruttenden,[570] who visited the Somali coast in 1843, says that myrrh is brought from the Wadi Nogâl, south west of Cape Gardafui, and from Murreyhan, Ogadain and Agahora; and that some few trees are found on the mountains behind Bunder Murayah. Major Harris[571] saw the myrrh tree in the Adel desert and in the jungle of the Háwash, on the way from Tajura to Shoa.

Vaughan[572] states that the Somali Country and the neighbourhood of Hurrur (or Harar or Adari, 9° 20′ N., 42° 17′ E.) south west of Zeila are the chief producing districts. It is generally brought to the great fair of Berbera held in November, December, and January, where it is purchased by the Banians of India, and shipped for Bombay.

It appears that all these informations rather refer to the Bisabol or Habaghadi variety of myrrh; only the first notice, due to Hildebrandt, applies to true myrrh.

Myrrh trees abound on the hills about Shugra and Sureea in the territory of the Fadhli or Fudthli tribe, lying to the eastward of Aden; myrrh is collected from them by Somalis who cross from the opposite coast for the purpose and pay a tribute for the privilege to the Arabs, who appear to be scarcely acquainted with this drug.[573] But a sample of it, received by one of us from Vaughan in 1852, and others we have since seen in London (and easily, recognized), proved it to be somewhat different from typical myrrh, and it is probably afforded by another species than Balsamodendron Myrrha.

It would thus appear that there are three different trees affording myrrh, namely that just alluded to, secondly the “Habaghadi,” and thirdly that growing east of Aden.

Description—Myrrh consists of irregular roundish masses, varying in size from small grains up to pieces as large as an egg, and occasionally much larger. They are of an opaque reddish-brown with dusty dull surface. When broken, they exhibit a rough or waxy fracture, having a moist and unctuous appearance, especially when pressed, and a rich brown hue. The fractured, translucent surface often displays characteristic whitish marks which the ancients compared to the light mark at the base of the finger-nails. Myrrh has a peculiar and agreeable fragrance with an aromatic, bitter, and acrid taste. It cannot be finely powdered until deprived by drying of some of its essential oil and water; nor when heated does it melt like colophony.

Water disintegrates myrrh, forming a light brown emulsion, which viewed under the microscope appears made up of colourless drops, among which are granules of yellow resin. Alcohol dissolves the resin of myrrh, leaving angular non-crystalline particles of gum[574] and fragments of bark.

Chemical Composition—Myrrh is a mixture, in very varying proportions, of resin, mucilaginous matters, and essential oil. A fine specimen of myrrh from the Somali coast, with which Captain Hunter, in 1877, kindly presented one of us, yielded 27 per cent. of resin. The undissolved portion is partly soluble in water.

The resin dissolves completely in chloroform or alcohol, and the colour of the latter solution is but slightly darkened by perchloride of iron. It is but partially soluble in alkalis or in bisulphide of carbon. Brückner (1867) found this portion to yield 75·6 per cent. of carbon and 9·5 of hydrogen. The resin which the bisulphide refuses to dissolve, is freely soluble in ether. It contains only 57·4 per cent. of carbon. The resin of myrrh to which, when moistened with alcohol, a small quantity of concentrated nitric or hydrochloric acid is added, assumes a violet hue, but far less brilliant than that displayed by resin of galbanum when treated in a similar manner. But a most intensely violet liquid may be obtained by adding bromine to the resin dissolved in bisulphide of carbon. If the resin of myrrh as afforded by alcohol is warmed with petroleum (boiling at 70° C.), only a small amount of resin is dissolved. This liquid becomes turbid if vapours of bromine are added; a violet flocculent matter deposits, whereas the just above-mentioned solution in the bisulphide continues clear on addition of bromine.

The resin of myrrh is not capable of affording umbelliferone like that of galbanum. By melting it with potash, pyrocatechin and protocatechuic acid are produced in small amount.

Myrrh yields on distillation a volatile oil which in operating on 25 lb. of the drug, we obtained to the extent of ¾ per cent.[575] It is a yellowish, rather viscid liquid, neutral to litmus, having a powerful odour of myrrh and sp. gr. 0·988 at 13° C.[576] In a column 50 mm. long, it deviates a ray of light 30·1° to the left. By submitting it to distillation, we obtained before the oil boiled, a few drops of a strongly acid liquid having the smell of formic acid. Neutralized with ammonia, this liquid produced in solution of mercurous nitrate a whitish precipitate which speedily darkened, thus indicating formic acid, which is developed in the oil. Old myrrh is in fact said to yield an acid distillate. The oil begins to boil at about 266° C., and chiefly distills over between 270° and 290°.

On combustion in the usual way it afforded carbon 84·70, hydrogen 9·98. Having been again rectified in a current of dry carbonic acid, it had a boiling point of 262-263° C., and now afforded[577] carbon 84·70, hydrogen 10·26, which would nearly answer to the formula C₂₂H₃₂O. The results of Ruickholdt’s analysis (1845) of essential oil of myrrh assign it the formula C₁₀H₁₄O, which is widely different from that indicated by our experiments.

The oil which we rectified displays a faintly greenish hue; it is miscible in every proportion with bisulphide of carbon, the solution exhibiting at first no peculiar coloration when a drop of nitric or sulphuric acid is added. Yet the mixture to which nitric acid (1·20) has been added, assumes after an hour or two a fine violet hue which is very persistent, enduring even if the liquid is allowed to dry up in a large capsule. If to the crude oil dissolved in bisulphide of carbon bromine be added, a violet hue is produced; and if the solution is allowed to evaporate, and the residue diluted with spirit of wine, it assumes a fine blue which disappears on addition of an alkali. The oil is not much altered by boiling with alcoholic potash, nor does it combine with alkaline bisulphites.

The Bitter principle of myrrh is contained in the resin as extracted by alcohol. By exhausting the resin with warm water an acid brown solution is obtained, from which a dark, viscid, neutral mass separates if the liquid is concentrated; it is contaminated with a large amount of inorganic matter, from which it may be purified by means of ether. Yet the latter affords also but an amorphous, somewhat brittle brown substance, softening at 80°-90° C. This bitter principle reminds us of that mentioned in our article Elemi, page 151; it is but sparingly soluble in water; the yellowish solution is intensely bitter. The bitter principle of myrrh appears to be a glucoside. We have not succeeded in preparing it in a more satisfactory state.

Commerce—Myrrh is chiefly shipped by way of Berbera to Aden, and thence either to Europe or to Bombay. The exports of Aden in the fiscal year 1875 to 1876 were 1439 cwt.; one-half of which went to Bombay, one third to the United Kingdom.[578]

The bags or bales which contain the myrrh are opened in Bombay, and the drug is sorted. The better portion goes to Europe, the refuse to China, where it is probably used as an incense.[579]

Uses—Myrrh, though much used, does not appear to possess any very important medicinal powers, and is chiefly employed on account of its bitter, aromatic properties.

Other Varieties of Myrrh—Though the myrrh of commerce exhibits some diversity of appearance, the drug-brokers and druggists of London are not in the habit of applying any special designations to the different qualities. There are however two varieties which deserve notice.

1. Bissa Bol (Bhesabol, Bysabole), Habaghadi or Hebbakhade of the Somalis, formerly called East India Myrrh.[580]

This drug is of African origin, but of the plant which yields it nothing is known. Vaughan[581] who sent a sample from Aden to one of us in 1852, was told by the natives that the tree from which it is collected resembles that affording Heera Ból or true myrrh, but that it is nevertheless distinct. The drug is exported from the whole Somali coast to Mokha, Jidda, Aden, Makulla, the Persian Gulf, India and even China.[582] Bombay official returns show that the quantity imported thither in the year 1872-73, was 224 cwt, all shipped from Aden.

Some myrrh, no doubt that from the interior of north-eastern Africa, the Habaghadi or Baisabole, finds its way by the country of the Wagadain (Ugahden or Ogadain) to the small port of Brava (Barawa, Braoua), about 1° N. lat., and to Zanzibar.[583] This is, possibly, also the “Mirra fina” which is stated, about the year 1502, by Tomé Lopez to be collected (?) in the island of “Monzambiche.”[584]

According to Vaughan, Bissa Bôl is mixed with the food given to milch cows and buffaloes in order to increase the quantity and improve the quality of their milk, and that it is also used as size to impart a bright gloss to whitewashed walls.

Miles mentions[585] that myrrh, called there hodthai, is only used in the Somali country, by men to whiten their shields (by means of an emulsion made with the drug), by women to cleanse their hair. Probably hodthai and habaghadi is one and the same thing.

Bissa Bôl differs from myrrh in its stronger, almost acrid taste and in odour, which, when once familiar is easily recognizable; fine specimens of the former have the outward characters of myrrh and perhaps are often passed off for it. A good sample of “coarse” habaghadi myrrh as sent in 1877 by Captain Hunter from Aden proved to contain but very little resin. This resin is manifestly different from that of myrrh as already shown by its paler, more reddish colour. The resin of Bissa Bôl moreover is but very sparingly soluble in bisulphide of carbon; this solution is not altered by bromine, that of true myrrh, as above stated, assuming a most intense violet colour on addition of bromine. Nor is the resin of habaghadi soluble in petroleum ether. Of the gummy substance, which is by far the prevailing constituent of this drug, a small portion only is soluble in water. These extremely marked differences no doubt depend upon a widely discrepant composition of the resins of the two kinds of myrrh as well as upon a different proportion of gum and resin. The Bissa Bôl usually seen is an impure and foul substance, which is regarded by London druggists as well as by the Banian traders in India as a very inferior dark sort of myrrh.

2. Arabian Myrrh—The drug we have mentioned at p. 143 as collected to the eastward of Aden, is of interest as substantiating the statement of Theophrastus that both olibanum and myrrh grow in Southern Arabia.

The drug, which is not distinguished by any special name in English trade, is in irregular masses seldom exceeding 1½ inches long, and having a somewhat gummy-looking exterior. The larger lumps seem formed by the cohesion of small, rounded, translucent, externally shining tears or drops. The fracture is like that of common myrrh, but less unctuous and wants the whitish markings. The odour and taste are those of the ordinary drug. Pieces of a semi-transparent papery bark are attached to some of the lumps. We extracted the resin of a sample of this myrrh from the territory of the Fadhli, as sent to us by Captain Hunter. Its solution in bisulphide of carbon or petroleum ether was coloured by bromine as stated above, (p. 144) with regard to typical myrrh (Heerabol) from the Somali Country. The name applies to myrrh from the vicinity of Ras Morbat in the same region. But the resin of another kind of Arabian myrrh, for which we are likewise indebted to Captain Hunter, is not coloured when treated in the same way. This is the myrrh “Hodaidia Jebeli” from north and north-western Yenen.

ELEMI.

Resina Elemi; Elemi; F. Résine Elemi; G. Elemiharz.

Botanical Origin—The resin known in pharmacy as Elemi is derived from a tree growing in the Philippines, which Blanco,[586] a botanist of Manila, described in 1845 under the name of Icica Abilo, but which is completely unknown to the botanists of Europe. Blanco’s description is such that, if correct, the plant cannot be placed in either of the old genera Icica or Elaphrium, comprehended by Bentham and Hooker in that of Bursera, nor yet in the allied genus Canarium; in fact even the order to which it belongs is somewhat doubtful.[587]

The tree grows in the province of Batangas in the island of Luzon (south of Manila), where its name in the Tagala language is ábilo; the Spaniards call it Arbol a brea, i.e. pitch-tree, from the circumstance that its resin is used for the caulking of boats.

History—The explicit statements of Theophrastus in the 3rd century b.c. relative to olibanum have already been mentioned. The same writer narrates[588] that a little above Coptus on the Red Sea, no tree is found except the acacia (ἀκάνθη) of the desert ... but that on the sea there grow laurel (δάϕνη) and olive (ἐλαία), from the latter of which exudes a substance much valued to make a medicine for the staunching of blood.

This story appears again in Pliny[589] who says that in Arabia the olive tree exudes tears which are an ingredient of the medicine called by the Greeks Enhæmon, from its efficacy in healing wounds.

Dioscorides[590] briefly notices the Gum of the Ethiopian olive, which he likens to scammony; and the same substance is named by Scribonius Largus[591] who practised medicine at Rome during the 1st century.

The writers who have commented on Dioscorides have generally adopted the opinion that the exudation of the so-called olive tree of Arabia and Ethiopia was none other than the substance known to them as Elemi, though, as remarked by Mattioli,[592] the oriental drug thus called by no means well accords with the description left by that author.

As to that name, the earliest mention of it appears in the middle of the 15th century. Thus in a list of drugs sold at Frankfort about 1450, we find Gommi Elempnij.[593] Saladinus,[594] who lived about this period, enumerates Gumi Elemi among the drugs kept by the Italian apothecaries, but we have not met with the name in any other writer of the school of Salerno. The Arbolayre,[595] a herbal supposed to have been printed about 1485, gives some account of Gomme Elempni, stating that it is the gum of the lemon tree and not of fennel as some think,—that it resembles Male Incense,—and makes an excellent ointment for wounds.

The name Enhæmon[596] of Pliny, also written Enhæmi, is probably the original form of the word Animi, another designation for the same drug, though also applied as at the present day to a sort of copal. It is even possible that the word Elemi has the same origin.[597]

This primitive Elemi is in our opinion identical with a peculiar sort of olibanum known as Luban Meyeti, afforded by Boswellia Frereana Birdwood (p. 135). It has a remarkable resemblance both in external appearance and in odour to the substance in after-times imported from America, and which were likened to the elemi and animi of the Old World. The description of “gummi elemnia” given by Valerius Cordus,[598] the most careful observer of his period, could in our opinion well apply to Luban Meyeti. (See p. 153 further on.)

The first reference to Elemi as a production of America comes from the pen of Monardes[599] who has a chapter on Animi and Copal. He describes animi as of a more oily nature than copal, of a very agreeable odour, and in grains resembling olibanum but of larger size, and adds that it differs from the animi of the Old World in being less white and clear.

At a somewhat later period this resin and some similar substances began to be substituted for Elemi which had become scarce.[600] Pomet,[601] who as a dealer in drugs was a man of practical knowledge, laments that this American drug was being sold by some as Elemi, and by others as Animi or as Tacamaca. It was however introduced in great plenty, and at length took the place of the original elemi which became completely forgotten.

American Elemi was in turn discarded in favour of another sort imported from the Philippines. The first mention of this substance is to be found among the descriptions accompanied by drawings sent by Father Camellus to Petiver of London, of the shrubs and trees of Luzon,[602] in the year 1701. Camellus states that the tree, which from his drawing preserved in the British Museum appears to us to be a species of Canarium, is very tall and large, that it is called by the Spaniards Arbol de la brea, and that it yields an abundance of odorous resin which is commonly used for pitching boats. Living specimens of the tree together with samples of the resin were brought to Paris from Manila by the traveller Perrottet about the year 1820. For the last twenty years the resin has been common, and is now imported in large quantities[603] for use in the arts, so displacing all other kinds. It has been adopted as the Elemi of the British Pharmacopœia (1867), and is in fact the only variety of elemi now found in English commerce.

Description—Manila elemi is a soft, resinous substance, of granular consistence not unlike old honey, and when recent and quite pure is colourless; more often it is found contaminated with carbonaceous matter which renders it grey or blackish, and it is besides mixed with chips and similar impurities. By exposure to the air it becomes harder and acquires a yellow tint. It has a strong and pleasant odour suggestive of fennel and lemon, yet withal somewhat terebinthinous. When moistened with spirit of wine, it disintegrates, and examined under the microscope is seen to consist partly of acicular crystals. At the heat of boiling water the hardened drug softens, and at a somewhat higher temperature fuses into a clear resin.

Chemical Composition—Manila elemi is rich in essential oil. On submitting 28 lb. of it to distillation with water, we obtained 2 lb. 13 oz. (equivalent to 10 per cent.) of a fragrant, colourless, neutral oil, of sp. gr. 0·861 at 15° C. Observed in Wild’s polaristrobometer we found it to be strongly dextrogyre.[604] H. Sainte Claire Deville[605] on the other hand has examined an oil of elemi that was strongly levogyre. This discrepancy shows that there are among the oils of various kinds of elemi, differences similar to those existing in the oils of turpentine and copaiba. By the action of dry hydrochloric acid gas, Deville obtained from his oil of elemi a solid crystalline substance, C₁₀H₁₆ + 2 HCl. We failed to produce any such compound from the oil of Manila elemi. Our oil of elemi dissolves in bisulphide of carbon; when mixed with concentrated sulphuric acid, it becomes thick and assumes a deep orange colour.

By submitting the crude oil to fractional distillation, we separated it into six portions, of which the first five were dextrogyre in gradually diminishing degree, while the sixth displayed a weak deviation to the left.[606] The first portion having been dissolved in four times its weight of strong sulphuric acid, washed and again distilled, exhibit a deviation to the left.[607]

If the essential oil of elemi (8 parts) is shaken with alcohol, 0·816 sp. gr. (2 parts), nitric acid, 1·2 sp. gr. (1 part) and water (5 parts), the mixture, on exposure to air in a shallow capsule soon yields large crystals, which were found to agree crystallographically[608] perfectly with terpin, C₁₀H₂₀O₂ + OH₂ from oil of turpentine.

Maujean,[609] a French pharmacien, examined Manila elemi as long ago as 1821 and proved it to contain two resins, the one soluble in cold, the other only in hot spirit of wine. The former, which appears to constitute by far the prevailing part of all varieties of elemi, has not yet been satisfactorily examined. Bonastre[610] a little latter made a more complete analysis, showing that the less soluble resin which he obtained to the extent of 25 per cent. is easily crystallizable, and apparently identical with a substance obtainable in a similar manner from what he regarded as true elemi, which the Manila resin was not then held to be. Baup (1851) gave it the name of Amyrin. According to our experiments, it is readily isolated to the extent of 20 per cent. when Manila elemi is treated with cold spirit of wine, in which the crystals of amyrin are but slightly soluble. If the elemi is pure, the amyrin may be thus obtained (by washing with spirit and pressure between bibulous paper) in a cake of snowy whiteness, which may be further purified by crystallization from boiling alcohol. The fusing point of the crystals is 177° C.; their composition has been ascertained by Buri[611] to agree with the formula C₂₅H₄₂O, which may be written thus: (C₅H₈)₅ OH₂. Amyrin at 16° C. dissolves in 27·5 parts of alcohol 0·816 sp. gr., being readily soluble also in all the usual solvents for resins. The alcoholic solution is slightly dextrogyre. Amyrin is a neutral substance, and may be sublimed in small quantities by very carefully heating it.

By heating amyrin with zinc dust Ciamician[612] obtained chiefly toluol, methyl-ethyl-benzol and ethyl-naphtalin.

By allowing an alcoholic solution of the amorphous resin of Manila elemi[613] to evaporate, Baup obtained in very small quantity crystals of Bréine, a substance fusing at 187° C., which he considered to be distinct from amyrin. In our opinion it was impure amyrin; it is extremely difficult, or rather practically impossible to extract all the crystallizable resin from the amorphous. If the latter, perfectly transparent, is kept for several years, an elegant crystallization at last begins to make its appearance throughout the bulk of the resin.

Baup further extracted from Manila elemi a crystallizable substance soluble in water to which he gave the name of Bryoidin,[614] and in smaller quantity a second also soluble in water which he called Bréidine. From the experiments of Baup it appears that bryoidin is soluble in 360 parts of water at 10° C., and melts at 135° C.; whereas bréidine requires for solution 260 parts of water and fuses at a temperature not much over 100° C.

We have also obtained Bryoidin[615] by operating in the following manner: the watery liquid left in the still after the distillation of 28 lb. of Manila elemi was poured off from the mass of hard resin, and having been duly concentrated, it deposited together with a dark extractiform matter, colourless acicular crystals of bryoidin. The deposit in question having been drained and allowed to dry, the bryoidin may be separated by boiling water or by cold ether. We found the latter the more convenient; it readily takes up the bryoidin contaminated only with a little resin. The ethereal solution should be allowed to evaporate and the residual crystalline mass boiled in water, when the solution (which is colourless), poured off from the resin, will deposit upon cooling brilliant tufts of acicular crystals of bryoidin. The boiling in water requires to be several times repeated before the whole of the bryoidin can be removed; the latter sometimes crystallizes as a mossy arborescent growth. Bryoidin is a neutral substance, of bitter taste, scarcely soluble in cold water, but dissolving easily in boiling water, or in alcohol or ether. When a little is placed in a watch-glass, covered with a plate of glass, and then gently heated over a lamp, it sublimes in delicate needles. To obtain it perfectly pure, it is best to sublime it in a current of dry carbonic acid. Thus purified its fusing point is 133·5 C.; after fusion it concretes as a transparent, amorphous mass, which if immersed in glycerin and raised to the temperature of 135° C., suddenly crystallizes.

We have observed that if the filtered mother-liquor of bryoidin after complete cooling and standing for a day or two is warmed, it becomes turbid and that in a few minutes there separate from it long white flocks like bits of paper or wool, which do not disappear either by warming or by cooling the liquid; under the microscope they are seen to consist partly of thread-like, partly of acicular crystals. It is possible this substance is Baup’s Bréidine; we found it to fuse at 135° C., to be neutral, and to crystallize from weak alcohol exactly like bryoidin. Both it and bryoidin look very voluminous in water, but are extremely small in weight, and are present in the drug in but a very small amount. The composition of bryoidin agrees with the formula C₂₀H₃₈O₃, which might be written thus (C₅H₈)₄+3OH₂. But it contains no water of crystallization. In the vapour of dry hydrochloric gas, bryoidin assumes a fine red colour, turning violet, then blue, and lastly green. This behaviour is not at all displayed by amyrin.

The liquids from which bryoidin is obtained contain an amorphous brown substance of intensely bitter taste, at the same time somewhat aromatic. It is decomposed by dilute mineral acids, evolving a very peculiar strong odour.

Buri[616] isolated from Manila Elemi an extremely small amount of Elemic acid, C₃₅H₅₆O₄. It is in very brilliant crystals, much larger than those of the other constituents of elemi. Although we have before us some prisms of the acids several millimetres long, it has been found impossible to ascertain their crystallographic character, each of the prisms being formed of very intimately aggregated crystals. Elemic acid melts at 215° C.; its alcoholic solution decidedly reddens litmus. Elemate of potassium is a crystalline salt.

The relations of the substances hitherto isolated from elemi may perhaps be given thus:—

Essential oil, C₅H₈.  
Amyrin, (C₅H₈)₅  +   OH₂
Amorphous resin (?)   (C₅H₈)₂  +   OH₂
Bryoidin, (C₅H₈)₄  + 3OH₂
Elemic acid, (C₅H₈)₇  +   O₄

Uses—Elemi is scarcely used in British medicine except in the form of an ointment, sometimes prescribed as a stimulating application to old wounds.

Other sorts of Elemi—1. Mexican Elemi, Vera Cruz Elemi—This drug, which used to be imported into London about thirty years ago, but which has now disappeared from commerce, is the produce of a tree named by Royle Amyris elemifera growing at Oaxaca in Mexico.[617] It is a light yellow, or whitish, brittle resin occurring in semi-cylindrical scraped pieces, or in irregular fragments which are sometimes translucent but more often dull and opaque. It easily softens in the mouth so that it may be masticated, and has an agreeable terebinthinous odour. Treated with cold spirit of wine (·828), it breaks down into a white magma of acicular crystals (Amyrin?).

2. Brazilian Elemi—Was described as long ago as 1658 by the traveller Piso, as a substance completely resembling the elemi of the Old World and applicable to the same purposes. It is the produce of several trees described as species of Icica, as I. Icicariba DC.,[618] I. heterophylla DC., I. heptaphylla Aublet, I. guianensis Aubl., I. altissima Aubl.—In New Granada a similar exudation[619] is furnished by I. Caranna H.B.K.

A specimen in our possession from Pernambuco[620] is a translucent, greenish yellow, fragrant, terebinthinous resin, which by cold spirit of wine may be separated into two portions, the one soluble, the other a mass of colourless acicular crystals. The resin spontaneously exuded and collected from the trunks, is often opaque and white, grey, or yellowish, looking not unlike fragments of old mortar. The microscope shows it to be made up of minute acicular crystals.[621]

3. Mauritius Elemi—Fine specimens of this substance and of Colophonia Mauritiana DC. the tree affording it, were sent to one of us (H.) in 1855 by Mr. Emile Fleurot of Mauritius. The resin accords in its general characters with Manila elemi, like which it leaves after treatment with cold spirit of wine, an abundance of crystals resembling amyrin.

4. Luban Meyeti[622] or Luban Mati.—This substance, which we claim to be the Oriental or African Elemi of the older writers, and also one of the resins anciently designated Animi,[623] is the exudation of Boswellia Frereana Birdwood, a remarkable tree gregarious on the bare limestone hills near Bunder Murayah to the west of Cape Gardafui. The tree which is called Yegaar by the natives, is of small stature, and differs from the other species of Boswellia growing on the same coast in having glabrous, glaucous leaves with obtuse leaflets, crisped at the margin.[624] The bark is smooth, papery, and translucent, and easily stripped off in thin sheets which are used for writing on. Though growing wild, the trees are said by Capt. Miles[625] to be carefully watched and even sometimes propagated. The resin exudes after incision in great plenty, soon hardens, and is collected by the Somali tribes who dispose of it to traders for shipment to Jidda and ports of Yemen: occasionally a package reaches London among the shipments of olibanum. It is used in the East for chewing like mastich.

In modern times Luban Mati has been mentioned by Wellsted in his “Travels in Arabia” (1838).

Luban Meyeti occurs in the form of detached droppy tears and fragments, occasionally in stalactitic masses several ounces in weight. It breaks very easily with a brilliant conchoidal fracture, showing an internal substance of a pale amber yellow and perfectly transparent. Externally it is more or less coated with a thin opaque white crust, which seen under the microscope appears non-crystalline. Many of the tears have pieces of the thin, brown, papery bark adhering to them. The resin has an agreeable odour of lemon and turpentine, and a mild terebinthinous taste.

Treated with alcohol (·838) it is almost entirely dissolved; the very small undissolved portion is not crystalline. The former agrees with the formula C₂₀H₃₀O₂. 20 lb. of Luban Mati yielded us 10 ounces of a volatile oil (= 3·1 per cent.) having a fragrant odour suggestive of elemi and sp. gr. 0·856 at 17° C. The oil examined in a column 50 millim. long, deviates the ray 2°·5 to the left. By fractional distillation we found it to consist of dextrogyre hydrocarbon, C₁₀H₁₆, mixed with an oxygenated oil which we did not succeed in isolating; the latter is evidently lævogyre, and exists in proportion more than sufficient to overcome the weak dextrogyre power of the hydrocarbon.

There is no gum in this exudation; it is therefore essentially different from olibanum, the product of closely allied species of Boswellia.[626]