Chapter XXVI: Part 26

=Production=—The manna of commerce is collected at the present day exclusively in Sicily. The principal localities producing the drug are the districts around Capaci, Carini, Cinisi, and Favarota, small towns 20 to 25 miles west of Palermo near the shores of the bay of Castellamare; also the townships of Geraci, Castelbuono, and other places in the district of Cefalù, 50 to 70 miles eastward of Palermo.

The manna-ash, in the districts whence the best manna is obtained, does not at the present day form natural woods, but is cultivated in regular plantations called _frassinetti_. The trees, which attain a height of from 10 to 20 feet, are planted in rows and stand about 7 feet apart, the soil between being at times loosened, kept free from weeds, and enriched by manure. After a tree is 8 years old and when its stem is at least 3 inches in thickness, the gathering of manna may begin; and may continue for 10 or 12 years, when the stem is usually cut down, and a young one brought up from the same root takes its place. The same stump thus has often two or three stems rising from it.

To obtain manna, transverse cuts from 1½ to 2 inches long and 1 inch apart, are made in the bark, just reaching to the wood. One cut is made daily, beginning at the bottom of the tree, the second directly above the first, and so on while dry weather lasts. In the following year, cuts are made in the untouched part of the stem, and in the same way in succeeding seasons. When after some years the tree has been cut all round and is exhausted, it is felled. Pieces of sticks or straws are inserted in the incisions, and become encrusted with the very superior manna, called _Manna a cannolo_, which however is unknown in commerce as a special sort. The fine manna ordinarily seen appears to have hardened on the stem of the tree. The manna which flows from the lower incisions, and is often collected on tiles or on a cup-shaped piece of the stem of the prickly pear (_Opuntia_), is less crystalline, and more gummy and glutinous, and is regarded of inferior quality.

The best time for notching the stems is in July and August, when the trees have ceased to push forth more leaves. Dry and warm weather is essential for a good harvest. The manna after removal from the tree, is laid upon shelves in order that it may dry and harden before it is packed. The masses left adhering to the stem after the finer pieces have been gathered, are scraped off and form part of the _Small Manna_ of commerce.[1510]

=Secretion=—We have examined microscopically the bark of stems of _Fraxinus Ornus_ that had been incised for manna at Capaci. It exhibits no peculiarity explaining the formation of manna, or any evidence that the saccharine exudation is due to an alteration of the cell-walls as in the case of tragacanth. The bark is poor in tannic matter; it contains starch, and imparts to water a splendid fluorescence due to the presence of _Fraxin_.

[1510] Our account of the production of manna has been derived from the observations of Stettner, who visited Sicily in the summer of 1847 (_Archiv der Pharm._ iii. 194; also Wiggers’ _Jahresbericht_, 1848. 35; _Hooker’s Journ. of Bot._ i. 1849. 124), from those of Cleghorn (_Trans. of the Bot. Soc. of Edinburgh_, x. 1868-69. 132), and from personal investigations made by one of us in the neighbourhood of Palermo in May 1872. See Hanbury, _Science Papers_, 367.

=Description=—Various terms have been used by pharmacological writers to designate the different qualities of manna, but in English commerce they are not now employed; and the better kinds of the drug are called simply _Flake Manna_, while the smaller pieces, usually loosely agglutinated and sold separately, are termed _Small Manna_ or _Tolfa Manna_.

Owing to the gradual exudation of the juice and the deposition of one layer over another, manna has a stalactitic aspect. The finest pieces are mostly in the form of three-edged sticks, sometimes as much as 6 to 8 inches long and an inch or more wide, grooved on the inner side, which is generally soiled by contact with the bark; of a porous, crystalline, friable structure and of a pale brownish yellow tint, becoming nearly pure white in those parts which have been most distant from the bark of the tree. The pieces which are of deeper colour, and of an unctuous or gummy appearance, are less esteemed. Good manna is crisp and brittle, and melts in the mouth with an agreeable, honey-like sweetness, not entirely devoid of traces of bitterness and acridity. Its odour may be compared to that of honey or moist sugar.

Manna of the best quality dissolves at ordinary temperatures in about six parts of water, forming a clear, neutral liquid. It contains besides mannite, a small proportion of sugar and gum.

The manna which exudes from the older stems and from the lower parts of even young trees, contains more or less considerable quantities of gum and fermentable sugar, as well as extraneous impurities. The less favourable weather of the later summer and autumn promotes an alteration in the composition of the juice, and impairs its property of concreting into a crystalline mass.

=Chemical Composition=—The predominant constituent of manna, at least of the better sorts, is _Manna-sugar_ or _Mannite_, C₆H₈(OH)₆ which likewise occurs, though in much smaller quantity, in many other plants besides _Fraxinus_. Artificially, it is produced by treating glucose, C₆H₁₂O₆, with sodium amalgam, and indirectly in the fermentation of glucose or of cane-sugar. It is isomeric with dulcite or melampyrin; crystallizes in shining prisms or tables, belonging to the rhombic system; melts at 166° C., and in very small quantity may by careful heating be sublimed and decomposed. It dissolves in 6·5 parts of water at 16° C., less freely in aqueous alcohol, very sparingly in absolute alcohol, and not in ether. The solution has an extremely weak rotatory power, and is not altered by boiling with dilute acids or alkalis, or with alkaline cupric tartrate.

Berthelot has shown that mannite is susceptible of fermentation, though not so easily as sugars belonging to the group of carbo-hydrates. The quantity of mannite in the best manna varies from 70 to 80 per cent.

When a solution of manna is mixed with alkaline cupric tartrate, rapid reduction to cuprous hydrate takes place even in the cold. This effect is due to the presence of a sugar which, according to Backhaus (1860), consists of ordinary dextro-glucose. It may amount to as much as 16 per cent., and is found in the best flake manna, but most abundantly in the unctuous varieties. Buignet[1511] has pointed out that the rotatory power of this sugar being inconsiderable, it probably consists of a mixture of _Cane-sugar_ and _Levulose_. He found however that an aqueous solution of manna deviates powerfully to the right, a fact which he considers due to the presence of a large proportion of _Dextrin_. The best kinds of manna, according to Buignet, contain about 20 per cent. of dextrin; the inferior much more.

[1511] _Journ. de Pharm._ vii. (1867) 401; viii. (1868) 5.

In our experiments we have not succeeded in isolating either dextrin or cane-sugar. There is present, even in the finest manna, a small amount of a dextrogyre mucilage, which is precipitated by neutral acetate of lead, and yields mucic acid when boiled with concentrated nitric acid.

Ether extracts from an aqueous solution of manna a very small quantity of red-brown resin, having an offensive odour and sub-acrid taste; together with traces of an acid which reduces silver salts and appears to be easily resinified. The quantity of water in the inferior kinds of manna often amounts to 10 or 15 per cent. The finest manna affords about 3·6 per cent. of ash.

The greenish colour of certain pieces of manna was formerly attributed to the presence of copper, till Gmelin, on account of the fluorescence of the solution, ascribed it to _Æsculin_. It is in reality produced by a body much resembling æsculin, namely _Fraxin_, C₁₆H₁₈O₁₀, occurring in the bark of the manna-ash and of the common ash, and together with æsculin, in that of the horse-chestnut. Fraxin crystallizes in colourless prisms, easily soluble in hot water and in alcohol, and having a faintly astringent and bitter taste. By dilute acids, it is resolved into _Fraxetin_, C₁₀H₈O₃, and _Glucose_, C₆H₁₂O₆. The presence of fraxin in manna, especially in the inferior sorts, is made apparent by the faint fluorescence of the alcoholic manna solution. The smallest fragment of the bark of the ash or the manna-ash immersed in water displays the same fluorescence.

=Commerce=—The exports of manna from Sicily[1512] (chiefly from Palermo) have been as follows:—

1869 1870 1871
2546 cwt., 1564 cwt., 3038 cwt.,
val. £15,972. val. £10,220. val. £19,528.

About half the quantity is sent to France. Italian commercial statistics[1513] represent the export of manna in 1870 thus:—_in canelli_ 58,691 kilo. (1155 cwt.), _in sorte_ 186,664 kilo. (3676 cwt.). The United Kingdom imported in the year 1870, 230 cwt. of manna, valued at £4447.[1514]

[1512] _Report by Consul Dennis on the Commerce and Navigation of Sicily in 1869, 1870 and 1871._

[1513] Direzione generale delle Gabelle—_Movimento commerciale del regno d’Italia nel 1870_, Milano, 1871.

[1514] _Annual Statement of the Trade and Navigation of the U.K. for 1870_, p. 102.

In 1877 the exports of “canelli” from Messina were 4273 kilogrammes, and of the drug “in sorte” 52,874 kilogr.; total value, 127,145 lire.

=Adulteration=—It can hardly be said that manna is subject to adulteration, though attempts to introduce a spurious manna made of glucose have been recorded. But considerable skill and ingenuity have been expended in converting the inferior sorts of manna into what has the aspect of fine natural Flake Manna, the manufacturers admitting however the factitiousness of their product. The artificial Flake Manna has the closest superficial resemblance to very fine pieces of the natural drug, but differs in its more uniform colour, and in being uncontaminated with the slight impurities, from which natural manna is never wholly free. It differs also in that when broken, no crystals of mannite are to be seen in the interstices of the pieces, and it wants the peculiar odour and slightly bitter flavour of natural manna. If one part of it is boiled with four of alcohol (0·838), a viscid honey-like residue will be obtained, whereas natural manna leaves undissolved a hard substance. Histed[1515] found it to afford about 40 per cent. of mannite, while fine manna similarly treated yielded 70 per cent.

=Uses=—A gentle laxative, much less frequently employed in this country than formerly, but still largely consumed in South America. Mannite, which possesses similar properties, is often prescribed in Italy.

Other sorts of Manna.

Various plants besides _Fraxinus_ afford, under certain conditions, saccharine exudations, some of which constituted the _Oriental Manna_ used in Europe in early times. So far as is known, they differ from officinal manna in containing no mannite.

_Alhagi Manna_; _Turanjabín_ (Arabic); is afforded by _Alhagi Camelorum_ Fisch. (Hedysarum Alhagi Pallas, non L.), a small spiny plant of the order _Leguminosæ_ found in Persia, Afghanistan and Beluchistan. It had already been noticed by Isztachri.[1516] Excellent specimens of the manna, kindly obtained for us in the north-west of India by Dr. E. Burton Brown and Mr. T. W. H. Tolbort, show it as a substance in little roundish, hard, dry tears, varying from the size of a mustard seed to that of a hemp seed, of a light brown colour, agreeable saccharine taste, and senna-like smell. The leaflets, spines and pods of the plant, mixed with the grains of this manna, are characteristic and easily recognizable.

Villiers (1877) showed this manna to contain cane-sugar, a dextrogyrate glucose, and _melezitose_ (see further on: Briançon manna, page 416). Ludwig[1517] had also found some dextrin and mucilage.

Alhagi Manna is collected near Kandahar and Herat, where it is found on the plants at the time of flowering. It is imported into India from Kabul and Kandahar to the extent of about 25 _maunds_ (2000 lb.) annually; its value is reckoned at 30 rupees per _secr_, = 30_s._ per lb.[1518]

[1515] _On artificial Flake Manna_, in _Pharm. Journ._ xi. (1870) 629.

[1516] Tchihatcheff, _l’Asie mineure_, ii. (1856) 355.

[1517] _Archiv der Pharmacie_, 193 (1870) 32-52.

[1518] Stewart, _Punjab Plants_, Lahore (1869) p. 57; Davies, _Report on the trade and resources of the countries on the N. W. boundary of British India_, Lahore, 1862.

_Gaz-anjabin_ (Arabic); _Tamarisk Manna_ (in part)—In the months of June and July, the shrubs of tamarisk (_Tamarix gallica_ var. _mannifera_ Ehrenb.) growing in the valleys of the peninsula of Sinai, especially in the Wady es Sheikh, exude from their slender branches, in consequence of the puncture of an insect (_Coccus manniparus_ Ehrenb.) little honey-like drops, which in the coolness of early morning are found in a solid state. This substance is _Tamarisk Manna_: it is collected by the Arabs, and by them sold to the monks of St. Katharine, who dispose of it to the pilgrims visiting the convent. Tamarisk Manna is also produced (but is perhaps no longer collected?) in Persia, where it is called _Gaz-angabín_;[1519] and probably likewise in the Punjab,[1520] from which regions it may have been brought to Europe in ancient times.

A specimen of tamarisk manna brought from Sinai, examined in 1861 by Berthelot, had the appearance of a thick yellowish syrup, contaminated with vegetable remains. It was found to consist of cane-sugar, inverted sugar (lævulose and glucose), dextrin and water, the last constituting one-fifth of the whole.[1521]

Although the name _Gaz-angabín_ signifies _tamarisk-honey_, it is used according to Haussknecht[1522] at the present time in Persia, to designate certain round cakes, common in all the bazaars, of which the chief constituent is a manna collected in the mountain districts of Chahar-Mahal and Faraidan, and especially about the town of Khonsar, south-west of Ispahan, from _Astragalus florulentus_ Boiss. et Haussk. and _A. adscendens_ Boiss. et Haussk. The best sorts of this manna, which are termed _Gaz Alefi_ or _Gaz Khonsari_, are obtained in August by shaking it from the branches, the little drops finally sticking together and forming a dirty, greyish-white, tough mass. The commoner sort got by scraping the stem, is still more impure. The specimen of it brought by Haussknecht yielded to Ludwig[1523] dextrin, uncrystallizable sugar and organic acids.

_Shir-khist_—Ancient writers on materia medica as Garcia d’Orta (1563) mention a sort of manna known by this name. The substance is still found in the bazaars of North-western India, being imported in small quantity from Afghanistan and Turkistan.[1524] Haussknecht in his paper on Oriental Manna already quoted, states that it is the exudation of _Cotoneaster nummularia_ Fisch. et Mey. (_Rosaceæ_), also of _Atraphaxis spinosa_ L. (_Polygonaceæ_), and that it is brought chiefly from Herat. We have to thank Dr. E. Burton Brown of Lahore, and Mr. Tolbort for specimens of this manna, which, from fragments it contains, is without doubt derived from a _Cotoneaster_. It is in irregular roundish tears, from about ¼ up to ¾ of an inch in greatest length, of an opaque dull white, slightly clammy, and easily kneaded in the fingers. It has a manna-like smell, a pure sweet taste and crystalline fracture. With water, it forms a syrupy solution with an abundant residue of starch granules.

Shír-khist was found by Ludwig to consist of an exudation analogous to tragacanth, but containing at the same time two kinds of gum, an amorphous levogyre sugar, besides starch and cellulose.

_Oak Manna_—The occurrence of a saccharine substance on the oak is noticed by both Ovid and Virgil, and it is also mentioned by the Arabian physicians, as Ibn Baytar[1525] and Elluchasem Elimithar.[1526] The last named, who died A.D. 1052, states that the exudation appears upon the oaks in the region of Diarbekir. At the present day, it is the object of some industry among the wandering tribes of Kurdistan, who, according to Haussknecht, collect it from _Quercus Vallonea_ Kotschy and _Q. persica_ Jaub. et Spach. These trees are visited in the month of August by immense numbers of a small white _Coccus_, from the puncture of which a saccharine fluid exudes, and solidifies in little grains. The people go out before sunrise, and shake the grains of manna from the branches on to linen cloths, spread out beneath the trees. The exudation is also collected by dipping the small branches on which it is formed, into vessels of hot water, and evaporating the saccharine solution to a syrupy consistence, which in this state is used for sweetening food, or is mixed with flour to form a sort of cake.

[1519] Angelus, _Pharm. Persica_ (see appendix) p. 359.

[1520] Stewart, _op. cit._ p. 92.

[1521] _Comptes Rendus_, liii. (1861) 583; _Pharm. Journ._ iii. (1862) 274.

[1522] _Archiv d. Pharmacie_, 192 (1870) 246.

[1523] _Loc. cit._

[1524] Davies in the work quoted at page 414, note 4.

[1525] Ed. Sontheimer, i. (1840) 375.

[1526] _Tacuini Sanitatis_, Argentorati (1531) 24.

A fine specimen of the Oak Manna of Diarbekir was sent to the London International Exhibition of 1862. It constituted a moist soft mass of agglutinated tears, much resembling an inferior sort of ash-manna, and had an agreeable saccharine taste.

A less pure form of this manna occurs as a compact, greyish, saccharine mass, sometimes hard enough to be broken with a hammer. It consists of sugary matter, mixed with abundance of small fragments of green leaves, and has a herby smell and pleasant sweet taste. A sample of it brought from Diarbekir, examined by one of us, yielded 90 per cent. of dextrogyre sugar, which could not be obtained in a crystalline state, though it exists in such condition in the crude drug. Starch and dextrine were entirely wanting.[1527]

A specimen furnished to Ludwig[1528] by Haussknecht afforded much mucilage, a small amount of starch, about 48 per cent. of dextrogyre grape sugar, with traces of tannic acid and chlorophyll.

_Briançon Manna_—This is a white saccharine substance which, in the height of summer and in the early part of the day, is found adhering in some abundance to the leaves of the larch (_Pinus Larix_ L.), growing on the mountains about Briançon in Dauphiny. It was formerly collected for use in medicine, but only to a very limited extent, for it was rare in Paris in the time of Geoffroy (1709-1731), and at the present day has quite disappeared from trade, though still gathered by the peasants. A specimen collected for one of us near Briançon in 1854, consists of small, detached, opaque, white tears, many of them oblong and channelled, and encrusting the needle-like leaf of the larch; they have a sweet taste and slight odour.[1529] Under the microscope they exhibit indistinct crystals.

Briançon manna has been examined in 1858 by Berthelot, who detected in it a peculiar sugar termed _Melezitose_, answering to the formula C₁₂H₂₂O₁₁ + OH₂.

Several other saccharine exudations have been observed by travellers and naturalists; we shall simply enumerate the more remarkable, referring the reader for further information to the original notices.

_Pirus glabra_ Boiss. affords in Luristan a substance which, according to Haussknecht, is collected by the inhabitants, and is extremely like Oak Manna. It is stated by the same traveller that _Salix fragilis_ L., and _Scrophularia frigida_ Boiss., likewise yield in Persia saccharine exudations. A kind of manna was anciently collected from the cedar, _Pinus Cedrus_ L.[1530] Manna is yielded in Spain by _Cistus ladaniferus_ L.[1531] _Australian Manna_, which is in small rounded, opaque, white, dry masses, is found on the leaves of _Eucalyptus viminalis_ Labill. It contains a kind of sugar called _Melitose_,[1532] has a sweet thistle, is devoid of medicinal properties and is not collected for use.[1533]

[1527] Further particulars, see Flückiger, _Ueber die Eichenmanna von Kurdistan_, in _Archiv der Pharmacie_, 200 (1872) 159.

[1528] _Loc. cit._ p. 35.

[1529] Hanbury, _Science Papers_, p. 438.

[1530] Geoffroy, _Mat. Med._ ii. (1741) 584.

[1531] Dillon, _Travels through Spain_ (1780) p. 127.

[1532] Gmelin, _Chemistry_, xv. 296.

[1533] _Pharm. Journ._ iv. (1863) 108.

The substance named _Tigala_ (corrupted into _Trehala_), from which a peculiar sugar has been obtained,[1534] is the coccoon of a beetle, and not properly a saccharine exudation.[1535]

The _Lerp Manna_ of Australia is also of animal origin.[1536] It consists of water 14, white thread-like portion 33, sugar 53 parts. The threads possess some of the characteristic properties of starch, from which they differ entirely by their form and unalterability even in boiling water. Yet in sealed tubes, they dissolve in 30 parts of water at 135° C. The sugar is dextrogyre; it impregnates the threads as a soft brown amorphous mass. In the purified state it does not crystallize, even after a long time. By means of dilute sulphuric acid, the threads are converted into crystalline grape sugar.

OLEUM OLIVÆ.

_Olive Oil_; _Salad Oil_; F. _Huile d’Olives_; G. _Olivenöl_; _Baumöl_; _Provencer Oel_.

=Botanical Origin=—_Olea europæa_ L., an evergreen tree,[1537] seldom exceeding 40 feet in height, yet attaining extreme old age, abundantly cultivated in the countries bordering the Mediterranean, up to an elevation of about 2000 feet above the sea-level.[1538] _Olea ferruginea_ Royle (_O. cuspidata_ Wallich), a tree abundant in Afghanistan, Beluchistan and Western Sind, has been supposed to be a wild form of _O. europæa_, but is regarded by Brandis[1539] as a distinct species. It is not known to have been ever cultivated, yet its fruit, which is of a small size and but sparingly produced, is capable of affording a good oil.

_History_—In ancient Egypt the olive was known by the term _bāk_; it can be traced as far as the 17th century before our era.[1540]

According to the elaborate investigations of Ritter[1541] and of A. De Candolle,[1542] the olive tree is a native of Palestine, and perhaps of Asia Minor and Greece. Its original area also extends over north-eastern Africa; Schweinfurth[1543] regards it as undoubtedly wild on the mountains of Elbe and Soturba in lat. 22 N. on the western shores of the Red Sea, a locality which he visited in 1868. The olive tree has also been met with as far eastward as the country of the Gallas, where it is much appreciated as affording excellent timber.[1544] It is also stated by Theophrastus, that in his time the tree was plentiful in the Cyrenaica, the modern Barca, in northern Africa.

[1534] _Comptes Rendus_, xlvi. (1858) 1276; Gmelin, _Chemistry_, xv. 299.

[1535] Belon, _Singularitez_ (1554) l. 2. cap. 91; Guibourt, _Comptes Rendus_ (1858) 1213; Hanbury, _Journ. Linn. Soc._, Zoology, iii. (1859) 178; also _Science Papers_, 158.

[1536] Dobson, _Proceedings of Royal Society of Van Diemen’s Land_, i. (1851) 234; _Pharm. Journ._ iv. (1863) 108; Flückiger, _Wittstein’s Vierteljahresschrift_, xvii. (1868) 161; _Archiv der Pharmacie_, 196 (1871) 7; abstracted in the _Yearbook of Pharmacy_, 1871. 188.

[1537] Readers desiring full information about the olive tree, its oil, its history, etc., should refer to the extremely exhaustive work of Coutance, _l’Olivier_, Paris, 1877, 456 pages, 120 figures.

[1538] Grisebach states the elevation above the sea of olive-cultivation thus:—Portugal (Algarve) 1400 feet; Sierra Nevada 3000; do., southern slope 4200; Nice 2400; Etna 2200; Macedonia 1200; Cilicia 2000.—_Die Vegetation der Erde nach ihrer klimatologischen Anordnung_, i. (1872) 262. 283. 342.

[1539] _Forest Flora of North-western and Central India_, 1874, 307.

[1540] Brugsch-Bey, _Reise nach der grossen Oase Kargeh_, Leipzig, 1878. 80. etc.—See also _Journ. of Botany_, 1879. 52.

[1541] _Erdkunde von Asien_, vii. (part 2. 1844) 516-537.

[1542] _Géographique Botanique_ (1855) 912.

[1543] _Bot. Zeitung_, 1868. 860.

[1544] Arnoux, _Revue des Deux Mondes_, Janvier 1879. 381.

The olive would appear to have been introduced at a very remote period into north-western Africa and Spain. Willkomm (1876) is of the opinion that it was originally a native of the whole Mediterranean region.

At the present day it is largely cultivated in Algeria, Spain, Portugal, Southern France, Italy, the Greek Peninsula and Asia Minor. In the Crimea the tree grows well, but does not afford good fruit. It was carried to Lima in Peru about 1560 and still flourishes there, and in great plenty in the coast valleys further south as far as Santiago in Chili.[1545]

Olive oil is mentioned in the Bible so frequently that it must have been an important object with the ancient Hebrews. It held an equally prominent place among the Greeks and Romans,[1546] whose writers on agriculture and natural history treat of it in the most circumstantial manner. Olive fruits preserved in brine were used by the Romans as an article of food,[1547] and were an object of commerce with Northern Europe as early as the 8th century.[1548]

=Production=—In common with many important cultivated plants, the olive occurs under several varieties differing more or less from the wild form, the finer of which are propagated by grafting. It is also increased by the suckers which old trees throw up from their naked roots, and which are easily made to develope into separate plants.[1549] The fruit, an oval drupe, half an inch to an inch or more in length, and of a deep purple, is remarkable for the large amount of fat oil contained in its pulpy portion (sarcocarp). The latter is most rich in oil when ripe, containing then nearly 70 per cent., besides 25 per cent. of water. The unripe fruit, as well as other parts of the plant, abounds in mannite, which disappears in proportion as the oil increases. The ripe olive contains no mannite, it having probably been transformed into fatty oil.[1550]

[1545] Perez-Rosales, _Essai sur le Chili_, Hambourg, 1857. 133.

[1546] Hehn, _Kulturpflanzen und Hausthiere in ihrem Uebergange aus Asien nach Griechenland und Italien_, Berlin, 1877. 88-142,—an interesting account of the importance of the olive in ancient times.

[1547] Specimens may be seen among the antiquities found at Pompei.

[1548] Diploma of Chilperic, A.D. 716.—Pardessus, _Diplomata_, _Chartæ_, etc., Paris, ii. (1849) 309.

[1549] Winter, in _Pharm. Journ._ Sept. 7, 1872.

[1550] De Luca in _Journ. de Pharm._ xlv. (1864) 65.—Some further researches by Harz on the formation of olive oil may be found in the _Jahresbericht_ of Wiggers and Husemann (1870) 392.

The process for extracting olive oil varies slightly in different countries, but consists essentially in subjecting the crushed pulp of the ripe fruit to moderate pressure. The olives, which are gathered from the trees, or collected from the ground, in November, or during the whole winter and early spring, are crushed under a millstone to a pulpy mass. This is then put into coarse bags, which, piled upon one another, are subjected to moderate pressure in a screw press. The oil thus obtained is conducted into tubs or cisterns containing water, from the surface of which it is skimmed with ladles. This is called _Virgin Oil_. After it has ceased to flow, the contents of the bags are shovelled out, mixed with boiling water, and submitted to stronger pressure than before, by which a second quality of oil is got. If the fruit is left for a considerable time in heaps it undergoes decomposition, yielding by pressure a very inferior quality of oil called in French _Huile fermentée_. The worst oil of all, obtained from the residues, has the name of _Huile tournante_ or _Huile d’enfer_.

It is said that in some districts the millstones are so mounted as to crush the pulp without breaking the olive-stones, and that thus the oil of the pulp is obtained unmixed with that of the kernels.[1551] We have made many inquiries in Italy and France as to this method of oil-making, but cannot find that it is anywhere followed.

The fixed oil of the kernels of ripe olives has been extracted and examined by one of us (F.). Though the kernels have a bitterish taste, the oil they yield is quite bland; by exposure to the vapour of hyponitric acid, it concretes like that of the pulp. If the whole of it were extracted in making olive oil, it would only be about as 1 part of oil of the _kernel_, to 40 parts of oil of the _pulp_.

=Description=—Olive Oil is a pale yellow or greenish yellow, somewhat viscid liquid, of a faint agreeable smell and of a bland oleaginous taste, leaving in the throat a slight sense of acridity.[1552] Its specific gravity on an average is 0·916 at 17° C. In cold weather, olive oil loses its transparency by the separation of a crystalline fatty body. The deposition takes place at a few degrees above the freezing point of water, and in some oils even at 10° C. (50° F.) If the oil is allowed to congeal perfectly, and is then submitted to strong pressure, about one-third of its weight of solid fat may be separated. After repeated crystallizations, this fat melts at 20 to 28° C. The fluid part or _Olein_, continues fluid at -4° to -10° C. Olive oil belongs to the class of the less alterable, non-drying oils.

The foregoing description does not apply to the inferior sorts of oil, which congeal more easily, are more or less deep-coloured, have a disagreeable odour and taste, and quickly turn rancid. These inferior oils have their special applications in the arts.

=Chemical Composition-=-The chief constituent of olive oil is _Olein_ or more correctly _Triolein_, C₃H₅(O·C₁₈H₃₃O)₃, identical so far as at present ascertained with the fluid part of all oils of the non-drying class. The proportion of olein in olive oil, as well as in other oils, is liable to variation, the result partly of natural circumstances and partly of the processes of manufacture. The best oils are rich in olein.

[1551] _The Grocer_, April 25, 1868, supplement; Pereira, _Elem. of Mat. Med._ ii. (1850) 1505.

[1552] This according to our experience is the case even with oil as it runs from the pulp and therefore in the freshest condition; but the acrid after-taste is more perceptible in oil which has been long kept.

As to the solid part of olive oil, Chevreul believed it to be constituted of _Margarin_, which he first examined in 1820. But Heintz (1852 and later) showed margarin to be a mixture of palmitin with other compounds of glycerin and fatty acids. Collett in 1854 isolated _Palmitic Acid_, C₁₆H₃₂O₂, from olive oil; and Heintz and Krug (1857) further proved that _Tripalmitin_ is the chief of the solid constituents of olive oil. They also met with an acid melting at 71°·4 C., which they regarded as _Arachic Acid_ (p. 187). As to stearic acid, Heintz and Krug did not fully succeed in evidencing its presence in olive oil.

Lastly, Benecke discovered in olive oil a small quantity of _Cholesterin_, C₂₆H₄₄O. It may be removed by means of glacial acetic acid or alcohol, which dissolve but very little of the oil.

=Commerce=—Various sorts of olive oil are distinguished in the English market, as Florence, Gallipoli, Gioja, Spanish (Malaga and Seville), Sicily, Myteline, Corfu and Mogador.

Olive oil was imported into the United Kingdom in the year 1872 to the value of £1,193,064. Nearly half the quantity was shipped from Italy, one-fifth from Spain, and the remainder from other Mediterranean countries.

The average annual production in Italy is estimated at about 3 millions of hectolitres (66 million gallons), but the quantity exported does not reach half that amount.

The statistics of the French Government indicate the annual production of olive oil in France to be not more than 250,000 hectolitres, equivalent in value to 30 millions of francs (£1,200,000).[1553]

=Uses=—The uses of olive oil in medicine and its immense consumption in the warmer parts of Europe as an article of food, are too well known to require more than a passing allusion.

=Adulteration=—Olive Oil is the subject of various fraudulent admixtures with less costly oils, the means of detecting which has engaged much attention. Of the various methods by which chemists have endeavoured to ascertain the purity of olive oil, the following are the more noteworthy:—

=a.= Drying oils (such as the oils of poppy and walnut) may be distinguished by their not being converted into solid crystallizable elaidin by hyponitric acid or concentrated solution of nitrate of protoxide of mercury. Olive oil which contains any considerable proportion of one of these oils, no longer solidifies if exposed for a moment to one of the above-mentioned reagents. This test however is not of sufficient delicacy for small amounts of drying oils.

=b.= Olive oil being one of the lighter oils, the specific gravity may to some degree indicate admixture with a heavier oil. To make use of this fact, Gobley and other chemists have invented an instrument called an _elaiometer_, for taking the specific gravity of oils.

=c.= Observation of the Cohesion-figure.—This test, proposed by Tomlinson in 1864,[1554] depends on the forces of cohesion, adhesion, and diffusion. Thus, if a drop of any oil hanging from the end of a glass rod is gently deposited upon the surface of chemically clean water, contained in a clean glass, a contest takes place between the forces in question the moment the drop flattens down by its gravity upon the surface of the water. The adhesion of the liquid surface tends to spread out the drop into a film, the cohesive force of the particles of the drop strives to prevent that extension, and the resultant of these forces is a figure which Mr. Tomlinson believes to be definite for every independent liquid. The figure thus produced is named the _cohesion-figure_.

[1553] Exposition de 1867 à Paris, _Rapports du Jury International_, xi. 108.—In the work of Coutance, quoted p. 417, note 7, nearly 400,000 hectolitres are calculated for the year 1866.

[1554] _Pharm. Journ._ v. (1864) 387. 495, with figures.

So far as our experience goes, the processes hitherto recommended for testing olive oil (and there are several that we have not mentioned) are only available in cases where the adulteration is considerable, and are quite insufficient for discovering a small admixture of other oils. How little they are appreciated, may be inferred from the fact that the Chamber of Commerce of Nice[1555] offered a reward of 15,000 francs (£600) for a simple and easy process for making evident an admixture with olive oil of 5 per cent. at least of any seed-oil.

APOCYNEÆ.

=CORTEX ALSTONIÆ.=

_Cortex Alstoniæ scholaris_; _Dita Bark_;[1556] _Alstonia Bark_.

=Botanical Origin=—_Alstonia[1557] scholaris_ R. Brown (_Echites scholaris_ L.), a handsome forest tree, 50 to 90 feet in height, common throughout the Indian Peninsula from the sub-Himalayan region to Ceylon and Burma; found also in the Philippines, Java, Timor and Eastern Australia, likewise in Tropical Africa. It has oblong obovate leaves, in whorls of 5 to 7, and slender pendulous pods a foot or more in length.

=History=—Saptachhada and saptaparna (literally seven-leaf), occurring in early Sanskrit epic poetry and also in Susruta, are ancient names of Alstonia (Dr. Rice). Rheede[1558] in 1678 and Rumphius[1559] in 1741 described and figured the tree, and mentioned the use made of its bark by the native practitioners. Rumphius also explained the trivial name _scholaris_ as referring to slabs of the close-grained wood which are used as school-slates, the letters being traced upon them in sand. The tonic properties of the bark were favourably spoken of by Graham in his _Catalogue of Bombay Plants_ (1839), and further recommended by Dr. Alexander Gibson in 1853[1560]. The drug has a place in the _Pharmacopœia of India_, 1868.

=Description=—The drug, as presented to one of us by the late Dr. Gibson and by Mr. Broughton of Ootacamund, consists of irregular fragments of bark, ⅛ to ½ an inch thick, of a spongy texture, easily breaking with a short, coarse fracture. The external surface is very uneven and rough, dark grey or brownish, sometimes with blackish spots; the interior substance and inner surface (liber) is of a bright buff. A transverse section shows the liber to be finely marked by numerous small medullary rays. The bark is almost inodorous; its taste is purely bitter and neither aromatic nor acrid.

[1555] _Annales de Chimie et de Physique_, March, 1869. 309.

[1556] From _Dita_, the name of the tree in the island of Luzon.

[1557] So named in honour of Charles Alston, Professor of Botany and Materia Medica (1740-1760) in the University of Edinburgh.—The plant is figured in Bentley and Trimen, _Med. Pl._ part 25 (1877).

[1558] _Hortus Malabaricus_, i. tab. 45.

[1559] _Herb. Amboin._ ii. tab. 82.

[1560] _Pharm. Journ._ xii. (1853) 422.

=Microscopic Structure=—The cortical tissue is covered with a thin suberous coat; the middle layer of the bark is built up of a thin walled parenchyme, through which enormous, hard, thick-walled cells are scattered in great numbers and are visible to the naked eye, as they form large irregular groups of a bright yellow colour. Towards the inner part these stone-cells disappear, the tissue being traversed by undulated medullary rays, loaded with very small starch grains; many of the other parenchymatous cells of the liber contain crystals of calcium oxalate. The longitudinal section of the liber exhibits large but not very numerous laticiferous vessels, containing a brownish mass, the concrete milk juice in which all parts of the tree abound.

=Chemical Composition=—The first attempts to isolate the active principles of this bark were made by two apothecaries, Scharlée at Batavia[1561] (1862) and Gruppe at Manila[1562] (1872).

In 1875 Jobst and Hesse exhausted the powdered bark with petroleum ether, and then extracted, by boiling alcohol, the salt of an alkaloid, which they called _Ditamine_. After the evaporation of the alcohol, it is precipitated by carbonate of sodium and dissolved by ether, from which it is removed by shaking it with acetic acid. Ditamine as again isolated from the acetate forms an amorphous and somewhat crystalline, bitterish powder of decidedly alkaline character; the barks yields about 0·02 per cent. of it.

From the substances extracted by means of petroleum ether, as above stated, Jobst and Hesse further isolated (1) _Echicaoutchin_, C₂₅H₄₀O₂, an amorphous yellowish mass; (2) _Echicerin_, C₃₀H₄₈O₂, forming acicular crystals, melting at 157° C.; (3) _Echitin_, C₃₂H₅₂O₂, crystallized scales, melting at 170°; (4) _Echiteïn_, C₄₂H₇₀O₂, which forms rhombic prisms, melting at 195°; (5) _Echiretin_, C₃₅H₅₆O₂, an amorphous substance melting at 52° C.

Echicaoutchin may be written thus: (C₅H₈)₅O₂, echicerin (C₅H₈)₆O₂, echiretin (C₅H₈)₇O₂; these formulæ at once point out how nearly the three last named substances are allied. They are probably constituents of the milky juice of the tree.

Lastly, Jobst and Hesse pointed out the existence of another alkaloid in Dita bark.

Harnack (1877) on the other hand is of the opinion that it contains only one alkaloid, which he terms _Ditaïne_. He used the alcoholic extract of the bark which he treated with ether to which he added a little ammonia. By this process ditamine of Jobst and Hesse would have been removed, but Harnack suggests that only a little ditaïne is dissolved by ether. He then mixed the extract with potash and exhausted it with alcohol, which afforded crystals of ditaïne, answering to the formula C₂₂H₃₀N₂O₄; its physiological action is nearly the same as that of curare. Ditaïne is but sparingly soluble in ether or petroleum ether, but dissolves readily in water, alcohol, or chloroform; it has a decidedly alkaline reaction. It would appear that it is a glucoside.

[1561] Geneesk, _Tijdschr. Nederl. Indië_, x. (1863) 209; also _Archiv der Pharmacie_, 212 (1878) 439.

[1562] _Jahresbericht_ of Wiggers and Husemann, 1873. 51.

Dita bark is stated[1563] to yield 5 per cent. of “ditaïne”; but this probably refers not to the pure alkaloid.

=Uses=—The bark has been recommended as a tonic and antiperiodic, being extravagantly praised as a substitute for quinine.

ASCLEPIADEÆ.

=RADIX HEMIDESMI.=

_Hemidesmus Root_, _Nunnari Root_, _Indian Sarsaparilla_.

=Botanical Origin=—_Hemidesmus indicus_ R. Brown (_Periploca indica_ Willd., _Asclepias Pseudo-sarsa_ Roxb.), a twining shrub, growing throughout the Indian Peninsula and in Ceylon. The leaves are very diverse, being narrow and lanceolate in the lower part of the plant, and broadly ovate in the upper branches.[1564]

=History=—In the ancient Sanskrit literature the plant occurs frequently under the name _Sārivā_, and its root under the name of _Nannārī_ or _Ananta-mūl_ (_i.e._ endless root) has long been employed in medicine in the southern parts of India.[1565] Ashburner in 1831 was the first to call the attention of the profession in Europe to its medicinal value.[1566] In 1864 it was admitted to a place in the _British Pharmacopœia_, but its efficiency is by no means generally acknowledged.

=Description=[1567]—The root is in pieces of 6 inches or more in length; it is cylindrical, tortuous, longitudinally furrowed, from ²/₁₀ to ⁷/₁₀ of an inch in thickness, mostly simple or provided with a few thin rootlets emitting slender, branching woody aerial stems, ³/₀ of an inch or less thick. Externally it is dark brown, sometimes with a slight violet-grey hue, which is particularly obvious in the sunshine. The transverse section of the hard root shows a white mealy or brownish or somewhat violet cortical layer, not exceeding ⅒ of an inch in thickness, and a yellowish woody column, separated by a narrow dark undulated cambial line. Neither the wood nor the cortical tissue present a radiate structure in the stout pieces; in the thinner roots, medullary rays are obvious in the woody part. The extremely thin corky layer easily separates from the bark, which latter is frequently marked transversely by large cracks. The root, whether fresh or dried, has an agreeable odour resembling tonka bean or melilot. The dried root has a sweetish taste with a very slight acidity. The stems are almost tasteless and inodorous. The root found in the English market is often of very bad quality.

[1563] _Yearbook of Pharm._ 1878. 624, from _Proc. of the American Pharm. Association_, 1877.

[1564] Fig. in Bentley and Trimen, _Med. Plants_, part 6 (1876).

[1565] There is an Indian root figured as _Palo de Culebra_ by Acosta (_Tractado de las Drogas ... de las Indias Orientales_, 1578, cap. lv.) which is astonishingly like the drug in question. He describes it moreover as having a sweet smell of melilot. The plant he says is called in Canarese _Duda sali_. The figure is reproduced in Antoine Colin’s translation, but not in that of Clusius.

[1566] _Lond. Med. and Phys. Journ._ lxv. 189.

[1567] Taken from excellent specimens obligingly sent to us from India by Dr. L. W. Stewart and Mr. Broughton.

=Microscopic Structure=—All the proper cortical tissue shows a uniform parenchyme, not distinctly separated into liber, medullary rays and mesophlœum. On making a longitudinal section however, one can observe some elongated laticiferous vessels filled with the colourless concrete milky juice. In a transverse section, they are seen to be irregularly scattered through the bark, chiefly in its inner layers, yet even here in not very considerable number. They are frequently 30 mkm. in diameter and not branched.

The wood is traversed by small medullary rays, which are obvious only in the longitudinal section. The parenchymatous tissue of the root is loaded with large, ovoid starch granules. Tannic matters do not occur to any considerable amount, except in the outermost suberous layer.

=Chemical Composition=—The root has not been submitted to any adequate chemical examination. Its taste and smell appear not to depend on the presence of essential oil, so far as may be inferred from microscopic examination; and it is probable the aroma is due to a body of the cumarin class. According to Scott,[1568] the root yields by simple distillation with water a stearoptene, which is probably the substance obtained by Garden in 1837, and supposed to be a volatile acid.

=Uses=—The drug is reputed to be alterative, tonic, diuretic and diaphoretic, but is rarely employed, at least in England.

CORTEX MUDAR.

_Cortex Calotropidis_; _Mudar_; F. _Ecorce de racine de Mudar_.

=Botanical Origin=—The drug under notice is furnished by two nearly allied species of _Calotropis_, occupying somewhat distinct geographical areas, but not distinguished from each other in the native languages of India. These plants are:—

1. _Calotropis procera_ R. Brown (_C. Hamiltonii_ Wight), a large shrub, 6 or more feet high, with dark green, oval leaves, downy beneath, abounding in acrid milky juice.

It is a native of the drier parts of India, as the Deccan, the Upper Provinces of Bengal, the Punjab and Sind, but is quite unknown in the southern provinces; it also extends to Persia, Palestine, the Sinaitic Peninsula, Arabia, Egypt, to the oasis Dachel, and other oases of the Sahara, to Nubia, Abyssinia, the lake Tsad and through the Sudan. Lastly it has been naturalized in the West Indies.

2. _C. gigantea_ R. Brown (_Asclepias gigantea_ Willd.), a large erect shrub, 6 to 10 feet high, with stem as thick as a man’s leg,[1569] much resembling preceding, indigenous to Lower Bengal and the southern parts of India, Ceylon, the Malayan Peninsula, and the Moluccas.

Both species are extremely common in waste ground over their respective areas.[1570]

[1568] _Pharm. of India_, 457; also _Chem. Gazette_, 1843. 378.

[1569] Hence the specific name _gigantea_.

[1570] The botanical distinctions between the two species may be stated thus:—

_C. procera_, corolla cup-shaped, petals somewhat erect, flower-buds spherical, appendages of corona with a blunt upward point. See Fig. in Bentley and Trimen, _Med. Plants_, part 25 (1877).

_C. gigantea_, corolla opening flat, flower-buds bluntly conical or oblong, appendages of corona rounded.

=History=—The ancient name of the plant, which occurs already in the Vedic literature, was _Arka_ (wedge), alluding to the form of the leaves which were used in sacrificial rites. From one of the Sanskrit names of this plant, namely _Mandāra_, Mudar is a corruption;[1571] the latter is frequently mentioned in the writings of Susruta.

The plant was likewise well known to the Arabian physicians.[1572]

_C. procera_ was observed in Egypt by Prosper Alpinus (1580-84), and upon his return to Italy was figured, and some account given of its medicinal properties.[1573] It is also the “Apocynum syriacum” figured by Clusius.[1574]

_C. gigantea_ was figured by Rheede[1575] in 1679, and in our own day by Wight.[1576]

The medicinal virtues of mudar, though so long esteemed by the natives of India, were not investigated experimentally by Europeans until the present century, when Playfair recommended the drug in elephantiasis, and its good effects were afterwards noticed by Vos (1826), Cumin (1827), and Duncan (1829). The last named physician also performed a chemical examination of the root-bark, the activity of which he referred to an extractive matter which he termed _Mudarine_.[1577]

=Description=—The root-bark of _C. procera_, as we have received it,[1578] consists of short, arched, bent, or nearly flat fragments, ⅛ to ⅕ of an inch thick. They have outwardly a thickish, yellowish-grey, spongy cork, more or less fissured lengthwise, frequently separating from the middle cortical layer; the latter consists of a white mealy tissue, traversed by narrow brown liber-rays. The bark is brittle and easily powdered; it has a mucilaginous, bitter, acrid taste, but no distinctive odour. The light yellow, fibrous wood is still attached to many of the pieces.

The roots of _C. gigantea_ are clothed with a bark which seems to be undistinguishable from that of _C. procera_ just described. The wood of the root consists of a porous, pale yellow tissue, exhibiting large vascular bundles, and very numerous small medullary rays, consisting of 1 to 3 rows of the usual cells.[1579]

[1571] Information for which we are indebted to Dr. Rice.

[1572] Ibn Baytar, translated by Sontheimer, ii. (1842) 193.

[1573] _De Plantis Ægypti_, Venet. 1592. cap. xxv.

[1574] _Rarior. plantar. hist._ ii. (1601) lxxxvii.

[1575] _Hortus Malabaricus_, ii. tab. 31.

[1576] _Illustrations of Indian Botany_, Madras, ii. (1850) tab. 155.—_C. procera_ is figured by the same author in his _Icones Plantarum Indiæ Orientalis_, iv. tab. 1278.

[1577] _Edinb. Med. and Surg. Journ._ xxxii. (1829) 60.

[1578] We are indebted for an authentic specimen to Dr. E. Burton Brown of Lahore.

[1579] Roots of _C. gigantea_ kindly supplied to us by Dr. Bidie of Madras consist of light, woody truncheons, ½ to 2¼ inches in diameter.

=Microscopic Structure=—In the root-bark of _C. procera_, the suberous coat is made up of large, thin-walled, polyhedral, or almost cubic cells; the middle cortical layer, of a uniform parenchyme, loaded with large starch granules, or here and there containing some thick-walled cells (sclerenchyme) and tufts of oxalate of calcium. The large medullary rays are built up of the usual cells, having porous walls and containing starch and oxalate. In a longitudinal section, the tissue, chiefly of the middle cortical layer, is found to be traversed by numerous laticiferous vessels, containing the dry milk juice[1580] as a brownish granular substance not soluble in potash.

The microscopic characters of the root-bark of _C. gigantea_ agree with those here detailed of _C. procera_. The stems of _Calotropis_ are distinguished by strong liber-fibres, which are not met with in the roots.

=Chemical Composition=—By following the process of Duncan above alluded to, 200 grammes of the powdered bark of _C. gigantea_ yielded us nothing like his _Mudarine_, but 2·4 grammes of an acrid _resin_, soluble in ether as well as in alcohol. The latter solution reddens litmus; the former on evaporation yields the resin as an almost colourless mass. If the aqueous liquid is separated from the crude resin, and much absolute alcohol added, an abundant precipitate of mucilage is obtained. The liquid now contains a bitter principle, which after due concentration may be separated by means of tannic acid.

We obtained similar results by exhausting the bark of _C. procera_ with dilute alcohol. The tannic compound of the bitter principle was mixed with carbonate of lead, dried and boiled with spirit of wine. This after evaporation furnished an amorphous, very bitter mass, not soluble in water, but readily so in absolute alcohol. The solution is _not_ precipitated by an alcoholic solution of acetate of lead. By purifying the bitter principle with chloroform or ether, it is at last obtained colourless. This bitter matter is probably the active principle of _Calotropis_; we ascertained by means of the usual tests that no alkaloid occurs in the drug. The large juicy stem, especially that of _C. gigantea_, ought to be submitted to an accurate chemical and therapeutical examination.[1581]

=Uses=—Mudar is an alterative, tonic and diaphoretic,—in large doses emetic. By the natives of India, who employ it in venereal and skin complaints, almost all parts of the plant are used. According to Moodeen Sheriff,[1582] the bark of the root and the dried milky juice are the most efficient; the latter is however somewhat irregular and unsafe in its action. The same writer remarks that he has found that the older the plant, the more active is the bark in its effects. He recommends that the corky outer coat, which is tasteless and inert, should be scraped off before the bark is powdered for use: of a powder so prepared, 40 to 50 grains suffice as an emetic.

The stems of _C. gigantea_ afford a very valuable fibre which can be spun into the finest thread for sewing or weaving.[1583]

[1580] It is evidently with a view to the retention of this juice, that the _Pharmacopœia of India_ orders the bark to be stripped from the roots when the latter are half-dried. Moodeen Sheriff remarks of _C. gigantea_, that although it is frequently used in medicine, no part of it is sold in the bazaars,—no doubt from the circumstance that the plant is everywhere found wild and can be collected as required.

[1581] List’s _Asclepione_ (Gmelin’s _Chemistry_, xvii. 368) might then be sought for.

[1582] _Supplement to the Pharmacopœia of India_, Madras, 1869. 364; for further information on the therapeutic uses of mudar, see also _Pharm. of India_, 458.

[1583] Drury, _Useful Plants of India_, 2nd ed. 1873. 101.

FOLIA TYLOPHORÆ.

_Country or Indian Ipecacuanha_.

=Botanical Origin=—_Tylophora asthmatica_ Wight et Arnott (_Asclepias asthmatica_ Roxb.), a twining perennial plant, common in sandy soils throughout the Indian Peninsula and naturalized in Mauritius. It may be distinguished from some of its congeners by its reddish or dull pink flowers, with the scale of the staminal corona abruptly contracted into a long sharp tooth.[1584]

=History=—The employment of this plant in medicine is well known to the Hindus, who call it _Antamul_ and use it with considerable success in dysentery, but we have not succeeded in tracing it in the ancient Indian literature. During the last century it attracted the attention of Roxburgh[1585] who made many observations on the administration of the root, while physician to the General Hospital of Madras from 1776 to 1778. It was also used very successfully in the place of ipecacuanha by Anderson, Physician-General to the Madras army.[1586] In more recent times, the plant has been prescribed by O’Shaughnessy, who pronounced the root an excellent substitute for ipecacuanha if given in rather larger doses.[1587] Kirkpatrick[1588] administered the drug in at least a thousand cases, and found it of the greatest value; he prescribed the _dried leaf_, not only because superior to the root in certainty of action, but also as being obtainable without destruction of the plant. The drug has been largely given by many other practitioners in India. _Tylophora_ is also employed in Mauritius, where it is known as _Ipéca sauvage_ or _Ipéca du pays_. It has a place in the _Bengal Pharmacopœia_ of 1844, and in the _Pharmacopœia of India_ of 1868.

=Description=[1589]—The leaves are opposite, entire, from 2 to 5 inches long, ¾ to 2½ inches broad, somewhat variable in outline, ovate or subrotund, usually cordate at the base, abruptly acuminate or almost mucronate, rather leathery, glabrous above, more or less downy beneath with soft simple hairs. The pedicel, which is channelled, is ½ to ¾ of an inch in length. In the dry state the leaves are rather thick and harsh, of a pale yellowish green; they have a not unpleasant herbaceous smell, with but very little taste.[1590]