chiefly mucilage, and (probably) pectin which separates if the liquid is concentrated by evaporation. The mucilage may be precipitated by neutral acetate of lead or by alcohol, but is not coloured by iodine. It may be separated by a filter into a portion truly soluble (as proved by the addition of alcohol or acetate of lead), and another, comprehending the larger bulk, which is only swollen like tragacanth, but is far more glutinous and completely transparent.

Neither a per- nor a proto-salt of iron shows the infusion to contain any appreciable quantity of tannin,' nor is the drug in any sense possessed of astringent properties.

Uses-Bael is held in high repute in India as a remedy for dysentery and diarrhoea; at the same time it is said to act as a laxative where constipation exists.

Adulteration-The fruit of Feronia Elephantum Correa, which has a considerable external resemblance to that of Egle Marmelos and is called by Europeans Wood Apple, is sometimes supplied in India for bael. It may be easily distinguished: it is one-celled with a large fivelobed cavity (instead of 10 to 15 cells) filled with numerous seeds. The tree has pinnate leaves with 2 or 3 pairs of leaflets. We have seen Pomegranate Peel offered as Indian Bael.2

SIMARUBEÆ.

LIGNUM QUASSIÆ.

Quassia, Quassia Wood, Bitter Wood; F. Bois de Quassia de la Jamaïque, Bois amer; Jamaica Quassiaholz.

Botanical Origin-Picræna excelsa Lindl. (Quassia excelsa Swartz, Simaruba excelsa DC., Picrasma excelsa Planchon), a tree 50 to 60 feet in height, somewhat resembling an ash and having inconspicuous greenish flowers and black shining drupes the size of a pea. It is common on the plains and lower mountains of Jamaica, and is also found in the islands of Antigua and St. Vincent. It is called in the West Indies Bitter Wood or Bitter Ash.

History Quassia wood was introduced into Europe about the middle of the last century. It was derived from Quassia amara L., a shrub or small tree with handsome crimson flowers, belonging to the same order, native of Panama, Venezuela, Guiana, and Northern Brazil. It was subsequently found that the Bitter Wood of Jamaica which Swartz and other botanists referred to the same genus, possessed similar properties, and as it was obtainable of much larger size, it has since the end of the last century been generally preferred. The wood of Q. amara, called Surinam Quassia, is however still used in France and Germany.3

1 We are thus at variance with Collas of Pondichery, who attributes to the ripe fruit 5 per cent. of tannin.-Hist. nat. etc. du Bel ou Vilva in Revue Coloniale, xvi. (1856) 220-238.

240 bags in a drug sale, 8th May, 1873. 3 The Pharmacopoea Germanica of 1872 expressly forbids the use of the wood of Picrana in place of Quassia.

The first to give a good account of Jamaica quassia was John Lindsay, a medical practitioner of the island, who writing in 1791 described the tree as long known not only for its excellent timber, but also as a useful medicine in putrid fevers and fluxes. He adds that the bark is exported to England in considerable quantity—" for the purposes of the brewers of ale and porter.'

Quassia, defined as the wood, bark, and root of Q. amara L., was introduced into the London Pharmacopoeia of 1788; in the edition of 1809, it was superseded by the wood of Picrana excelsa. In the stockbook of a London druggist (J. Gurney Bevan, of Plough Court, Lombard Street) we find it first noticed in 1781 (as rasura), when it was reckoned as having cost 4s. 2d. per lb.

Description-The quassia wood of commerce consists of pieces of the stem and larger branches, some feet in length, and often as thick as a man's thigh. It is covered with bark externally of a dusky grey or blackish hue, white and fibrous within, which it is customary to strip off and reject. The wood, which is of a very light yellowish tint, is tough and strong, but splits easily. In transverse section it exhibits numerous fine close medullary rays, which intersect the rather obscure and irregular rings resembling those of annual growth of our indigenous woody stems. The centre is occupied by a cylinder of pith of minute size. In a longitudinal section, whether tangential or radial, the wood appears transversely striated by reason of the small vertical height of the medullary rays.

The wood often exhibits certain blackish markings due to the mycelium of a fungus; they have sometimes the aspect of delicate patterns, and at others appear as large dark patches.

Quassia has a strong, pure bitter taste, but is devoid of odour. It is always supplied to the retail druggist in the form of turnings or raspings, the former being obtained in the manufacture of the Bitter Cups, now often seen in the shops.

Microscopic Structure-The wood consists for the most part of elongated pointed cells (libriform), traversed by medullary rays, each of the latter being built up of about 15 vertical layers of cells. The single layers contain from one to three rows of cells. The ligneous rays thus enclosed by medullary parenchyme, are intersected by groups of tissue constituting the above-mentioned irregular rings. On a longitudinal section this parenchyme exhibits numerous crystals of oxalate of calcium, and sometimes deposits of yellow resin. The latter is more abundant in the large vessels of the wood. Oxalate and resin are the only solid matters perceptible in the tissues of this drug.

Chemical Composition-The bitter taste of quassia is due to Quassiin, which was first obtained, no doubt, from the wood of Quassia amara, by Winckler in 1835. It was analysed by Wiggers, who assigned it the formula CH2O3, now regarded as doubtful. According to the latter, quassiin is an irresolvable, neutral substance, crystallizable from dilute alcohol or from chloroform. It requires for solution about 200 parts of water, but is not soluble in ether; it forms an insoluble compound with tannic acid. Quassia wood is said to yield about

1 Trans. Roy. Soc. Edinburgh, iii. (1794) 205. tab. 6.

2 Liebig's Annalen der Pharm. xxi. (1837) 40.

per cent. of quassiin. A watery infusion of quassia, especially if a little caustic lime has been added to the drug, displays a slight fluorescence, due apparently to quassiin. Goldschmiedt and Weidel (1877) failed in obtaining quassiin. They isolated the yellow resin which we mentioned above, and stated that it yields protocatechuic acid when melted with potash. Quassia wood dried at 100° C. yielded us 7.8 per cent. of ash.

Commerce-The quantity of Bitter Wood shipped from Jamaica in 1871 was 56 tons.1

Uses The drug is employed as a stomachic and tonic. It is poisonous to flies, and is not without narcotic properties in respect to the higher animals.

Substitutes-The wood of Quassia amara L., the Bitter Wood of Surinam, bears a close resemblance, both external and structural, to the drug just noticed; but its stems never exceed four inches in diameter and are commonly still thinner. Their thin, brittle bark is of a greyish yellow, and separates easily from the wood. The latter is somewhat denser than the quassia of Jamaica, from which it may be distinguished by its medullary rays being composed of a single or less frequently of a double row of cells, whereas in the wood of Picrana excelsa, they consist of two or three rows, less frequently of only one.

Surinam Quassia Wood is exported from the Dutch colony of Surinam. The quantity shipped thence during the nine months ending 30th Sept., 1872, was 264,675 lb.2

3

The bark of Samadera indica Gärtn., a tree of the same natural order, owes its bitterness to a principle which agrees perhaps with quassiin. The aqueous infusion of the bark is abundantly precipitated by tannic acid, a compound of quassiin probably being formed. A similar treatment applied to quassia would possibly easier afford quassiin than the extraction of the wood by means of alcohol, as performed by Wiggers.

BURSERACEÆ.

OLIBANUM.

Gummi-resina Olibanum, Thus masculum; 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

Blue Book, Island of Jamaica, for 1871.

2 Consular Reports, No. 3, presented to Parliament, July 1873.

3 Rost van Tonningen, Jahresbericht of Wiggers (Canstatt) for 1858. 75; Pharm. Journ. ii. (1872) 644. 654.

The Aißavos of the Greeks, the Latin Olibanum, as well as the Arabic Luban,

and the analogous sounds in other languages, are all derived from the Hebrew Lebonah, signifying milk: and modern travellers who have seen the frankincense trees state that the fresh juice is milky, and hardens when exposed to the air. The word Thus, on the other hand, seems to be derived from the verb Ovew, to sacrifice.

Africa, near Cape Gardafui and of the southern coast of Arabia. Notwithstanding the recent elaborate and valuable researches of Birdwood,' 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,2 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.

1 On the Genus Boswellia, with descriptions and figures of three new species.--Linn. Trans. xxvii. (1870) 111. 148. This paper is reprinted as an appendix to Cooke's "Report on the gums, resins,

of the Indian Museum," Lond. 1874.The original plates are much superior and more complete than the reprints.-The materials on which Dr. Birdwood's observations have been chiefly founded, and to which we also have had access, are,-1. Specimens collected during an expedition to the Somali Coast made by Col. Playfair in 1862.-2. Growing Plants at Bombay

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' and Hunter and to Haggenmacher 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 Luban Meyeti or Luban 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 Richard3 to be transparent; it consists no doubt merely of resin (and essential oil?) without gum.*

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.

5

History The use of olibanum goes back to a period of extreme antiquity, as proved by the numerous references 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 Phoenicians and Egyptians carried on with Arabia.

Professor Dümichen of Strassburg has discovered at the temple of

1See his picturesque description of the tree, Journ. R. Geograph. Soc. 22 (1872) 64.

2 Flückiger, Pharm. Journ. viii. (1878) 805.

3 Tent. Flora Abyssinicae, i. (1847) 248; figure of the tree tab. xxxiii.

See the paper quoted in note 2.

5 As for instance, Exod. xxx. 34; 1 Chron. x. 29; Matth. ii. 11.

6

Movers, Das phönizische Alterthum, iii. (1856) 99. 299.-Sprenger, l.c. p. 299, also points out the importance of the olibanum with regard to the commercial relations of those early periods.

7 Dümichen (Joannes), The fleet of an