Sex. Syst. Enneandria, Monogynia.
(Rheum Sinense; Rhei, species incerta; Radix, L. The root of undetermined species.—E. D.)
History.—Dioscorides [Lib. iii. cap. 11.] speaks of a root which he calls rha or rheon (ρά ρήον), and which has been regarded by some as identical with our rhubarb." Rha, by some called rheon, grows," says Dioscorides, "in those countries which are beyond the Bosphorus, and from which it is brought. It is a root which is black externally, like to great centaury, but smaller and redder, odourless, loose or spongy, and somewhat smooth internally." Pliny [Hist. Nat. lib. xxvi. cap. 105, ed. Valp.] gives a similar account of it, under the name of rhacoma; it comes, he says, from the countries beyond Pontus, resembles the black costus, is odourless, and has a hot, astringent taste. Prosper Alpinus [De Rhapontico, 1612.] was of opinion that the rha of Dioscorides was the root of Rheum rhaponticum, which Alpinus obtained from Thracia, in 1608, A. D., and cultivated at Pavia. The later Greek writers are supposed to have been acquainted with our rhubarb. Alexander of Tralles [Lib. viii. cap. 3.] is the first who speaks of it. He used it in weakness of the liver and dysentery. Paulus Aegineta says that, in the crudities and vomiting of pregnant women, we may give "the knot-grass, boiled in water, for drink; and likewise dill, and the pontic root, called rha in the dialect of its native country;" [Paulus Aegineta. Syd. Soc. edit, by Dr. Adams, vol. i. book i.] and, in noticing the practice of the ancients, he says," alvine discharges they promoted by giving turpentine to the extent of an olive, when going to rest; or, when they wished to purge more effectually, by adding a little rhubarb," [rheon.] [Ibid. book i. Sect. 43, p. 54. See also vol. iii. pp. 317 und 478.] This is the first notice of the purgative properties of rhubarb.
Tn one of the Arabian authors (Mesue, the younger) we find three kinds of rhubarb mentioned: The Indian, said to be the best; the Barbarian; and the Turkish, which is the worst of all.
Botany. Gen. Char.— Calyx petaloid, 6-parted, withering. Stamina about 9, inserted into the base of the calyx. Styles 3, reflexed. Stigmas peltate, entire. Achenium 3-cornered, winged, with the withered calyx at the base. Embryo in the centre of the albumen (Lindley).
It is not yet ascertained what species of Rheum yields the officinal rhubarb. Several species, now cultivated in this country, have been, at different times, declared to be partially or wholly the source of it. Formerly, Rheum Rhaponticum was supposed to yield it. [Alston, Mat. Med. vol. i. p. 502.]
In 1732, R. undulatum was sent from Russia to the Messrs. Jussieu at Paris, and to Rand of Chelsea, as the true rhubarb. This is the species which Linnaeus described as R. Rhabarbarum. [Ibid.] About 1750, at the desire of Kauw Boerhaave, first physician to the Emperor of Russia, the senate commissioned a Tartarian merchant, a dealer in rhubarb, to procure them some seeds of the genuine plant. This he did, or pretended to do; and,on sowing them, two species of Rheum were obtained; namely, the undulatum and the palmatum. [Murray, Mat. Med. vol. iv. p. 463.] In 1762, seeds of the latter species were received by Dr. Hope, of Edinburgh, from Dr. Mounsey, at Petersburg; they were sown, and the plants cultivated with success. [Hope, Phil. Trans. vol. lv. for the year 1765. p. 290.] The root of this species being found to agree, in many of its characters, with that of genuine rhubarb, led to the belief that the palmatum was the true species. The inquiries of Pallas, however, raised some doubts about the correctness of this opinion; for the Bucharians declared themselves unacquainted with the leaves of the palmatum, and described the true plant as having round leaves, with a few incisions only at the margin. This description agreed best with Rheum compactum, the roots of which were declared, by Millar, who cultivated the plant, to be as good as foreign rhubarb. [Murray, pp. 365-6.] Georgi says, that a Cossack pointed out to him the leaves of the R. undulatum as the true species.[Ibid. p. 360.] These accounts were not satisfactory to the Russians; and, in consequence, in 1790, Sievers, an apothecary, went to Siberia, under the auspices of Catherine II., with a view of settling the question; but, after four years of persevering attempts to reach the country where the true rhubarb grew, or even to obtain the seeds, he was obliged to be satisfied with negative results only. "My travels," says he, "as well as acquaintance with the Bucharians, have satisfied me that as yet nobody—that is, no scientific person—has seen the true rhubarb plant. All that is said of it by the Jesuits is miserable, confused stuff; all the seeds procured under the name of true rhubarb are false; all the plantations, from those of the Knight Murray down to the flowerpot of a private individual, will never yield true rhubarb. Until further determination, I hereby declare all the descriptions in all the Materia Medicas to be incorrect." [Duncan, Suppl. to the Edinb. New Disp. p. 89.] Calau, [Pharm. Journ. vol. ii. p. 658, 1843.] Apothecary in the Rhubarb Factory at Kiachta, and who, from his appointment, might be expected to know the origin of the rhubarb he receives from the Bucharians, says, "All that we know of the rhubarb plant or its origin is defective and wrong; every sacrifice to obtain a true plant or the seed has been in vain; nor has the author been enabled to obtain it. A severe prohibition from the Chinese government prevents all possibility of eliciting the truth."
Himalayan rhubarb is obtained from several species of Rheum : viz. R. Emodi, Wallich; [Bot. Mag. t. 3508.] R. Webbianum, Royle; [Illust. of the Bot. of the Himal. Mount.] R. spiciforme, Royle; and R. Moorcroftianum, Royle; but there are no reasons for supposing that they yield any of the rhubarb of European commerce. It is not improbable that the species yielding the officinal rhubarb is yet undescribed. Dr. Royle, [Op. cit.] after referring to the accounts of different authors, as to the precise locality of the country yielding Russian rhubarb, concludes that it is within 95° of E. long, in 35° of N. latitude—that is, in the heart of Thibet. And he adds, "as no naturalist has visited this part, and neither seeds nor plants have been obtained thence, it is as yet unknown what species yields this rhubarb."
The late Mr. Anderson, of the Apothecaries' Botanic Garden, Chelsea, furnished me with the fresh roots of thirteen species or Rheum : viz. R. palmatum, undulatum, compactum, Rhaponticum, Emodi, crassinervium, caspicum, tartaricum, hybridum, confluens, Fischeri, bardanifolium, and bullatum. Having carefully dried these by artificial heat, I found that one species only, viz. R. palmatum, closely resembled Asiatic rhubarb in the combined qualities of odour, colour, and marbling: R. undulatum agreed tolerably well in colour and marbling, but not in odour. It deserves, however, to be noticed that the specimens examined were of unequal ages—some forming the rootstock, others root-branches of the respective plants—a circumstance which considerably diminishes the value of a comparative examination of them. Furthermore, all the samples were probably injured by the wet season. The root-branches of R. crassinervium (from a strong plant of six or seven years old, but which had not flowered) did not resemble Asiatic rhubarb in either colour or odour. [In 1834, Geiger (Pharm. Central Blatt für 1834, S. 209) made a comparative examination of (he roots of R. Emodi. compactum, undulatum, and Rhaponticum.]
Species.—I. With compound racemes.
1. Rheum palmatum, Linn. L. D. Palmated Rhubarb. Commonly known to gardeners as the True Turkey Rhubarb.—" Leaves roundish-cordate, half pal. mate; the lobes pinnatifid, acuminate, deep dull green, not wavy, but uneven, and very much wrinkled on the upper side, hardly scabrous at the edge, minutely downy on the under side; sinus completely closed; the lobes of the leaf standing forward beyond it. Petiole pale green, marked with short purple lines, terete, obscurely channelled quite at the upper end. Flowering stems taller than those of any other species," (Lindley.)—Perennial. Grows spontaneously in the Mongolian empire, on the confines of China. [Murray, App. Med. vol. iv. p 363.] Its leaf-stalks make excellent tarts and puddings.
Prof. Guibourt [Hist. Des. Drogs.] observes that out of the roots of R. palmatum, undulatum, compactum, and Rhaponticum, those of the first species possess only the exact odour and taste (grittiness excepted) of the China rhubarb.
2. Rheum undulatum, Linn. D. Wave-leaved Rhubarb.—"Leaves oval, obtuse, extremely wavy, deep green, with veins purple at the base, often shorter than the petiole, distinctly and copiously downy on each side, looking as if frosted when young, scabrous at the edge; sinus open, wedge-shaped, with the lower lobes of the leaves turned upwards. Petiole downy, bloody, semicylindrical, with elevated edges to the upper side, which is narrower at the upper than the lower end," (Lindley.)—Perennial. Grows in Siberia (Georgi and Pallas, cited by Murray), [App. Med.] and China (Ammann, quoted by Lindley). Cultivated in France, and yields part of the French Rhubarb [Guibourt, Hist, des Drogues.] It was formerly cultivated at Siberia as the real officinal plant; but, as genuine rhubarb could not be procured from it, its cultivation has been given up. [Ibid.]
3. Rheum compactum, Linn.; Thick-leaved Rhubarb.—"Leaves heart-shaped, obtuse, very wavy, deep green, of a thick texture, scabrous at the margin, quite smooth on both sides, glossy and even on the upper side; sinus nearly closed by the parenchyma. Petiole green, hardly tinged with red, except at the base, semicylindrical, a little compressed at the sides, with the upper side broad, flat, bordered by elevated edges, and of equal breadth at each end," (Lindley.)—Perennial. Grows in Tartary and China. Cultivated in France, and yields part of the French rhubarb. [Guibourt. supra cit.] This rhubarb is a very fair imitation of that from China; but is distinguished by its reddish tint, its different odour (common to it, to R. undulatum, and R. rhaponticum), its close and radiated marbling, its not tinging the saliva, and its not grating under the teeth.
4. Rheum Emodi, Wallich; R. australe, Don.—"Leaves cordate, acute, dull green, but little wavy,flattish, very much wrinkled, distinctly rough, with coarse short hairs on each side; sinus of the base distinctly open, not wedge-shaped, but diverging at an obtuse angle, with the lobes nearly turned upwards. Petioles very rough, rounded angular, furrowed; with the upper side depressed, bordered by an elevated edge, and very much narrower at the upper than the lower end," (Lindley.)—Perennial. Grows on the Himalayas. It yields part of the Himalayan rhubarb. Its stalks make excellent tarts and puddings.
5. Rheum Webbianum, Royle. Choor Mountain, Niti Pass. Yields part of the Himalayan rhubarb.
6. Rheum Rhaponticum, Linn.; Common or Rhapontic Rhubarb.—Grows in Thrace; borders of the Euxine Sea; north of the Caspian; Siberia, &c. Cultivated in this country for the leaf-stalks, which are used for tarts and puddings; whence it is frequently termed culinary or tart rhubarb. Grown largely at Banbury, in Oxfordshire, on account of its roots, which, when dried, constitute English or Banbury rhubarb. [See note by the author, in the Pharmaceutical Journal, vol. vi. p. 76, 1846; also a paper by Mr. W. Bigg, in thee same volume, p. 74.] Cultivated also in France, and yields part of the French rhubarb.
7. R. crassinervium, Fischer.—Habitation unknown. Sent from St. Petersburg to the Apothecaries' Garden, Chelsea. Its roots possess, according, to the late Mr. Anderson, the colour and odour of Turkey rhubarb.[Lindley, Fl. Med.]
8. R. leucorrhizum, Pallas; R. nanum, Sievers. Ledebour, Fl. PI. Ross. t. 492. Deserts of the Kirghis, and south of Siberia and Altai Mountains. Said to yield white or imperial rhubarb.
9. R. hybridum, Murray, Comm. Gott. t. i.—Cultivated as a culinary rhubarb.
II. With spiciform racemes.
10. Rheum spiciforme, Royle.—Kherang Pass, and other places in Kunawar. Also Thibet.
11. Rheum Moorcroftianum, Royle; Small-stalked Rhubarb.—Niti Pass, in the Himalayas. This and the preceding species have denser and more yellow roots than the two other Himalayan species of Rheum above noticed (viz. R. Emodi and R. Webbianum).
Preparation.—The method of curing or preparing Asiatic rhubarb for the market varies somewhat in different localities. In China it is as follows: The roots are dug up, cleansed, cut in pieces, and dried on stone tables, heated beneath by a fire. During the process, the roots are frequently turned. They are after wards pierced, strung upon cords, and further dried in the sun. [Du Halde, Descript. Géograph. et Hist. de. la Chine, t. iii. p. 492.] In Tartary, the Moguls cut the roots in small pieces, in order that they may dry the more readily, and make a hole in the middle of every piece, through which a cord is drawn, in order to suspend them in any convenient place. They hang them, for the most part, about their tents, and sometimes on the horns of their sheep. [Bell, Travels from St. Petersburg to divers parts of Asia, vol. i. p. 311.] Sievers, however, states that the roots are cut in pieces, strung upon threads, and dried under sheds, so as to exclude the solar rays; and the same author tells us that sometimes a year elapses from the time of their collection until they are ready for exportation. [Duncan, Suppl. to the Edinb. New Disp. p. 88.]
Varieties and Description.—The various sorts of rhubarb (radix rhei) of commerce may be conveniently arranged in four divisions, respectively distinguished as Muscovitic or Russian, Canton, Himalayan, and European.
1. Muscovitic or Russian Rhubarb (Radix Rhei Muscovitici, Ruthenici vel Rossici).—Under this head are included those sorts of Asiatic rhubarb which are brought into Europe by way of Russia. The principal and chief sort is the Crown Rhubarb. Two other inferior sorts, called respectively Bucharian and Siberian Rhapontic Rhubarb, are occasionally imported, but are not found in the shops, Taschkent and White Rhubarb are other Russian sorts which I have not met with.
1. Russia Crown Rhubarb.—This is Chinese rhubarb, which is taken in exchange, on behalf of the Russian crown, at Kiachta. In Russia, it is known as Chinese rhubarb; in Europe, it is frequently called Bucharian rhubarb, not because it is the growth of Bucharia, but from the circumstance of a few Bucharian families having been the purveyors to the Russian crown for a century. It might with propriety be termed Chinese-Russian rhubarb. In English commerce, it is commonly called Turkey rhubarb (radix rhei turcici), because formerly this description of rhubarb came into Europe by way of Natolia. [Murray, App. Med. vol. iv. p. 379.]
The barter of rhubarb is carried on by the Russian government, under a contract made with Bucharians at Kiachta for ten years, and confirmed by the Chinese government. According to this contract, the Bucharians undertake to furnish a certain quantity of rhubarb annually to the Russian crown, for a certain quantity of goods of a certain quality, and to deliver up all rhubarb not approved of, without remuneration, and permit it to be burnt by the Russian government.
The rhubarb grows wild in Chinese Tartary, especially in the province Kansu. It is collected on that long chain of mountains of Tartary, destitute for the most part of woods, and which arises not far from the town of Selin, and extends to the south as far as the lake Kokonor, near Thibet. [Pallas, Voyages en différ. Prov. de l'Empire de Russie, t. iv. p. 216, et seq.] It is generally gathered in summer, from plants of six years of age. When the root is dug up it is washed, to free it from earthy particles, peeled, bored through the centre, strung on a thread, and dried in the sun. In autumn, all the dried rhubarb collected in the province is brought in horse-hair sacks, containing about 200 lbs. to Sinin (the residence of the dealers), loaded on camels, and sent over Mongolia to Kiachta, Canton, Macao, and partly to Pekin. All the rhubarb brought to Kiachta undergoes an examination, prescribed by the Imperial Russian Medical Council, according to directions of the Russian government. The selection of the rhubarb bartered for by Russian merchants takes place in the custom-house at Kiachta; and of that for the crown, in a house for that purpose on the Chinese borders.
In this selection, the following rules are chiefly to be observed:— [Calau, Pharm. Journ. vol. ii. p. 658, 1843.]
a. To reject pieces obtained from dead plants, which are porous, of a gray colour, and, besides fibre and oxalate of lime, contain little of the other constituents of rhubarb.
b. To reject pieces that are small, derived from young plants, and which are of a pale colour, and without much virtue.
c. To reject roots of other plants, which are casually or purposely mixed with the rhubarb.
d. To pare the rhubarb. This is done, first, to remove remaining portions of the bark and the upper part of the foot; and, secondly, to cleanse those parts that may be stained with the sweat of the camels.
e. To perforate all pieces, and examine their interior.
f. To re-dry those roots which may be moist.
As the rhubarb taken in exchange by the crown is not permitted to be imported into the European part of Russia, except in quantities of 1,000 poods, or 40,000 pounds, the roots approved of, after the examination, are packed in bags, and placed where there is a free current of air, until the necessary quantity has accumulated, which is then packed in cases capable of containing 4—5 poods. These chests are covered with linen and pitched, then sewed into skins and marked with the year of the importation of the root, and sent to Moscow.
Crown rhubarb is imported in chests holding from 156 to 160 lbs. each. Each chest is pitched on the outside and covered with a hempen cloth and a hide. On the outside of the chest is a printed paper, stating the year in which the rhubarb was imported into Russia, and the weight of the chest. The following is a literal copy (reduced in size) of one of these papers:—
The best prices are obtained for those chests whose rhubarb is in small pieces (for retailing), has a bright colour, and is sound and hard. The shapes of the pieces are various, being angular, rounded, irregular, &c. The flat surfaces and angles which the pieces present show that the cortical portion of the root has been removed by slicing (and not by scraping, as in the Canton rhubarb). Holes are observed in some of the pieces extending completely through; they have been made for the purpose of hanging the pieces to dry; but all traces of the cord have been carefully removed, and the holes scraped or filed to get rid of all decayed portions. The holes which extend only partially through the pieces are borings which have been made to examine the condition of the interior of the pieces.
Externally, the pieces are covered with a bright yellow-coloured powder, usually said to be produced by the mutual friction of the pieces in the chests during their passage to this country; though many druggists believe it is derived from the process of rouncing (that is, shaking in a bag with powdered rhubarb), before its exportation. The odour is strong and peculiar, but somewhat aromatic. It is considered by druggists to be so delicate, that in all wholesale drug-houses a pair of gloves is kept in the Russian rhubarb drawer, with which only are the assistants permitted to handle the pieces. When chewed, it feels gritty under the teeth, from the presence of numerous crystals of oxalate of lime; it communicates a bright yellow colour to the saliva, and has a bitter, slightly astringent taste.
Beneath the dust with which the pieces are covered, the surface has a reddish-white tint, owing to the intermixture of white and red parts. The yellowish-white parts have the form of lines or veins, which, by their union with each other, assume a reticular form. Irregularly scattered over the surface we observe small star-like spots and depressions, of a darker colour. The transverse fracture is uneven, and presents numerous brownish-red or dark carmine-coloured undulating veins. The longitudinal fracture is still more uneven, and shows the longitudinal direction of the veins, which are often interrupted with white. The surface obtained by cutting is more or less yellow, and often exposes the veins, disposed in groups.
By boiling very thin slices of the root in water, and then submitting them to the microscope, we observe cellular tissue annular ducts, and numerous conglomerate raphides (clumps of crystals of oxalate of lime). From 100 grs. of Russian rhubarb, the late Mr. Edwin Quekett procured between 35 and 40 grs. of these raphides. [Lindley's Introduction to Botany, 3d ed. p. 553.] Turpin considered the presence of these crystals sufficient to distinguish Russian and Chinese rhubarb from that grown in Europe; but in some specimens of English rhubarb I have met with them in as great abundance as in foreign rhubarb. According to Raspail, [Chim. Organ.] they are situated in the interstices of the elongated tissue; but this statement is erroneous, the situation of the crystals being in the interior of the cells.
The small pieces of crown rhubarb are usually picked out and sold as radix rhei turcici electa; the larger pieces and dust being employed for powdering.
The powder of Russian rhubarb is of a bright yellow colour, with a reddish tint; but, as met with in the shops, it is almost invariably mixed with the powder of English rhubarb.
2. White or Imperial Rhubarb.—When Pallas was at Kiachta, the Bucharian merchants, who supplied the crown with rhubarb, brought some pieces of rhubarb as white as milk, with a sweet taste, and the same properties as rhubarb of the best quality. [Voyages, t. iv. p. ] It is not met with in English commerce as a distinct kind; and it is almost unknown in Russia [Grassman; Buchner's Repert. Bd. xxxviii. S. 179, 1831.] But in the chests of Russian rhubarb there are occasionally found pieces having an unusually white appearance; these I presume to be the kind alluded to. [Consult Goebel and Kunze, Pharm. Waarenkunde.] White rhubarb is said to be the produce of R. leucorrhizum, Pallas (R. nanum, Sievers.)
3. Taschkent Rhubarb.—This is the refuse of the true Russian rhubarb, which comes by way of Taschkent. It differs but little from the crown rhubarb. On account of its cheapness, it, like the Bucharian sort, is employed for purposes for which the crown rhubarb of Russia is too expensive. I have not met with it in English commerce.
4. Bucharian Rhubarb (Rheum bucharicum.)—Grassman, an apothecary, at St. Petersburg, who has described this sort, [Buchner's Repertorium, Bd. xxxviii. S. 179, 1831.] considers it to be the rhubarb which, according to Pallas, is obtained from Rheum undulatum, and which, in the Pharmacopeia Rossica, for 1798, was denominated radix rharbarbi sibiriri. As it is not under the control of the crown, in Russia, it undergoes no examination, and inferior and rotten pieces, therefore, are often met with. On account of its cheapness it is used, in Russia, in veterinary medicine.
In 1840, some of it was received here by Mr. Faber, from Russia, to whom I am indebted for samples of it. It is described as being carried into the latter country by way of Nischny, where it is trimmed for the Moscow market.
This kind of rhubarb is intermediate between the Chinese and Russian or Muscovite rhubarb, but is of inferior quality. The pieces are, more or less, rounded or flattened, and weigh from one to two ounces each. Some of them appear to have been deprived of their cortical portion by scraping, as in the Chinese rhubarb; but in others, the cortex has been removed by slicing. Most of them are perforated by a hole, apparently for the purpose of drying them; but in none of the holes are there any remains of the cord used in suspending the roots. The holes, moreover, appear to have been cleaned out, as in the Russian rhubarb, for no portion of decayed rhubarb is seen in them. Some of the pieces are dense, but most of them are lighter than good Russian rhubarb. Internally, they are often decayed and dark coloured. Their texture is similar to that of genuine rhubarb. The odour is also like that of rhubarb, but much feebler; the taste is bitter and astringent. When chewed, this rhubarb feels gritty under the teeth. Its colour is darker than that of good Russian rhubarb.
5. Siberian Rhubarb; Rheum sibiricum. [For a notice of this and two preceding varieties, see a paper by the author in the Pharmaceutical journal, vol. iv. pp. 445 and 500, 1845.] —This is the sort which Grassman has described as Siberian rhapontic rhubarb. In 1815, three chests of it came to England from St. Petersburg, under the name of Bucharian rhubarb, and were sold by public sale at 6d. per. lb.
In its general appearance, it agreed with rhubarb grown in this country, and known as English stick rhubarb. It had been decorticated, though imperfectly so, as portions of the dark brown cortex were here and there left adherent. The pieces were all more or less cylindrical, seldom exceeding four inches in length and an inch in diameter, and on the average weighed about 100 grains each; the longest piece was six inches in length; and an inch and a half in diameter. The broadest piece was somewhat flattened, and about three inches in its broadest diameter. Its colour was, in general, darker than that of the ordinary rhubarb, but was of the same kind of tint. Its odour was remarkably sweet, similar to what I have perceived when drying the roots of different species of Rheum cultivated in England. When chewed it was not gritty. Its taste was mucilaginous, bitterish, but not astringent. The fracture of the smaller and sound pieces was similar to that of English stick rhubarb; the larger pieces were decayed, dark brown, and tasteless in the centre.
2. Canton Rhubarb.—This, like the Russian crown rhubarb, is the produce of China, but is exported from Canton. It is usually known in English commerce as
Chinese or East Indian rhubarb (radix rhei chinensis seu indici.) It is imported either directly from Canton, or indirectly by Singapore and other parts of the East Indies, and is probably the produce of the province of Se-tchuen (Du Halde), of Hoo-nan and Hoo-pih, as well as of other provinces (Gutzlaffe and Reed).
Three kinds of Canton rhubarb are known in commerce; these are, the untrimmed or half-trimmed, the trimmed, sometimes called the Dutch trimmed, and what I have called stick rhubarb.
6. Half trimmed or untrimmed Canton Rhubarb.—This is usually Chinese or East Indian rhubarb of the shops. It is called "untrimmed," or "half-trimmed," because the cortical portion of the root has been incompletely scraped (not sliced) off; and consequently the pieces have a rounded character, and are devoid of the flat surfaces and angles produced by slicing (as in the Russian and Dutch trimmed rhubarbs). The inferior pieces present the remains of the greenish-brown or blackish cortex. The pieces are frequently cylindrical or roundish, but sometimes flattened; in trade, they are distinguished as rounds and flats. They are generally perforated with holes, in many of which, we find portions of the cords by which they were suspended. These holes are smaller than those observed in Russian rhubarb, and that portion of the root forming their sides is usually dark-coloured, decayed, and of inferior quality. The best pieces are heavier and more compact than that of the Russian kind; and are covered with an easily separable dust. When this is removed, we observe that the surface is not so regularly reticulated, is of a more yellowish-brown than reddish-white colour, and has coarser fibres than Russian rhubarb. On the finer pieces, we notice numerous star-like spots or depressions. The fracture is uneven; the veins, especially towards the middle, have a less determinate direction, and are of a duller or reddish-brown colour, and, in very bad pieces, of an umber-brown colour, with a gray substance between the veins.
The odour of this species is much less powerful than that of Russian rhubarb, and is somewhat less aromatic. The taste, grittiness when chewed, and microscopic appearances, are similar to those of Russian rhubarb. The colour of the powder is of a more dull yellow or brownish cast.
This sort of rhubarb is imported in chests and half chests; the former contains one picul (133 ½ lbs.), the latter half a picul. The chests are oblong, have been coarsely put together, and, except in shape, resemble tea-chests; and, like the latter, are lined with sheet-lead. The cover is a double one.
When this sort arrives in London, it is hand-picked, tared, and sorted into three qualities—bright and sound, dark and horny, and worm-eaten. This is not done with Russian rhubarb.
7. Dutch-trimmed or Batavian Rhubarb, offic. (Rhubarbe de Perse, Gruibourt.)— This kind of rhubarb is closely allied to, if it be not identical with, the preceding in its texture. In commerce, however, it is always regarded as distinct. It is imported from Canton and Singapore in chests, each containing one picul, (133 ½ lbs.) It has been dressed or trimmed to resemble the Russian crown rhubarb, which it does in shape, size, and general appearance; for the cortical portion of the root seems to have been separated by slicing, and hence the pieces have the same angular appearance on the surface that the Russian rhubarb has. The pieces arc frequently perforated, and in the holes are found the remains of the cord by which the root has been suspended; in this it differs from the Russian crown rhubarb In the drug-trade, this kind of rhubarb is said to be trimmed, and, according to the shape of the pieces, they are called flats or rounds The colour and weight of the pieces are variable.
8. Canton Stick Rhubarb. [See a paper by the author in the Pharmaceutical Journal, vol. iv. p. 446, 1845.] —In 1844, five cases of this rhubarb were imported from Canton and were sold by public sale, at 8d. per pound.
All the pieces but one of my sample are cylindrical, about two inches long, from half to three-quarters of an inch in diameter, and weigh each on the average about 100 grains The piece to which I have referred as forming the exception is shaped like a flattened cylinder cut obliquely at one end; its greatest length is about two and a half inches, its greatest breadth two inches and a quarter; while its depth is about one inch, and its weight is about two ounces. Mr. Faber, from whom I received it, tells me, that on the examination of a quantity of Canton stick rhubarb he found several such pieces.
Most of the pieces are decorticated. These resemble English stick rhubarb in their texture and colour, except that they are, perhaps, somewhat paler. The taste is bitter, and somewhat astringent, but considerably less so than that of good, half-trimmed, Canton Rhubarb. By chewing it, little or no grittiness is perceptible.
This kind of rhubarb is probably obtained from the root-branches of the plant which yields the usual Canton rhubarb.
3. Himalayan Rhubarb (Radix Rhei Himalayanensis; Radix Rhei Indici).— Rhubarb, the produce of the Himalayas, which makes its way through the plains of India, through Kahlsee, Almora, and Butan, is probably, from its usual dark colour and spongy texture, the produce of either or both R. Emodi and R. Webbianum; the roots of R. spiciforme and R. Moorcroftianum being lighter coloured and more compact in structure.
I have met with two sorts of Himalayan rhubarb :—
9. Large Himalayan Rhubarb; Rhubarb from Rheum Emodi?—I am indebted to Dr. Wallich for some specimens of this sort of rhubarb. He obtained them from the inhabitants of the Himalayas, who had strung the pieces around the necks of their mules. It has scarcely any resemblance to the officinal rhubarb. The pieces are cylindrical, and are cut obliquely at the extremities; the cortex of the root is not removed; the colour is dark-brown, with a slight tint of yellow; they are without odour, and have a coarse fibrous texture.
In November, 1840, when China rhubarb was very scarce and dear, nineteen chests of Himalayan rhubarb were imported from Calcutta into this country. The chests were of the usual Calcutta kind, made of the hard, heavy, brittle Bengal wood. The weight per chest was gross 1 cwt, 2 qrs. 26 lbs.
The pieces varied considerably in size and shape; some were twisted, cylindrical, furrowed pieces, cut obliquely at the extremities, about four inches long, and an inch and a half in diameter. Others were circular disks, about three inches in diameter, two inches thick, and weighed about four ounces each. Besides these, semicylindrical, angular, and other-shaped pieces were met with, and were obviously obtained by slicing the root. Some of the pieces were decorticated, others were coated. The general colour was dark brown; the prominent decorticated and paler parts having an ochre-brown tint. It had a feeble rhubarb odour, and a bitter astringent taste. When broken, it did not present the marbled texture characteristic of ordinary rhubarb. By chewing it, little or no grittiness was perceived. It was exceedingly light, and worm-eaten.
This was the first shipment of Himalayan rhubarb ever made to this country. Two chests sold at 4d. per lb.; the remainder at 1d. per lb. [Dr. Royle (Illust. of the Botany of the Himalayan Mountains, p. 316.) says that the Himalayan rhubarb sells for only one-tenth of the price of the best rhubarb, resembling in quality the Russian, and which is found in India.]
10. Small Himalayan Rhubarb; Rhubarb from Rheum Webbianum.—I am indebted to Dr. Royle for this sort. It is the same as that referred to in the experiments of Mr. Twining. [Trans. Med. and Phys. Sur. of Calcutta, vol. iii. p. 411.] The pieces are short transverse segments of the root-branches, of a dark brownish colour, odourless, or nearly so, with a very bitter astringent taste, and in quality do not essentially differ from the roots given me by Dr. Wallich.
4. European Rhubarb (Radix Rhei Europaei).—This is rhubarb cultivated in Europe. The only two sorts with which I am acquainted are the English and French.
11. English Rhubarb (Radix Rhei Anglici).—This is the produce of Rheum Rhaponticum, cultivated in the neighbourhood of Banbury in Oxfordshire.
The history of this rhubarb is not a little curious. It appears that Mr. Wm. Hayward, an apothecary at Banbury, was the original cultivator of rhubarb in that locality. From his own statement [Trans. Society of Arts, vol. viii. pp. 75 and 76, 1790.] it appears that he began to cultivate it about the year 1777. [The cultivation of rhubarb in Britain was long since recommended by Sir William Fordyee in a work entitled The Great Importance and Proper Method of Cultivating and Curing Rhubarb in Britain for Medical Purposes, Lond. 1784.] In 1789 he obtained a silver medal, and in 1794 a gold medal, from the Society of Arts, for the cultivation of what he terms "the true Turkey rhubarb;" [Trans. Society Arts, vol. xii pp. 225-229, 1791.] the plant for which the Society offered the premium being the "R. palmatum, or true rhubarb." [Ibid. vols. vii. p. 281, and xi p. 285.] Mr. Hayward died in 1811, and his plants were purchased by the father of one of the present cultivators.
At present there are three cultivators of Banbury rhubarb; viz. Mr. R. Usher of Overthorpe and Bodicott, Mr. T. Tustian of Milcombe, and Mr. E. Hughes of Neithorp. These parties grow altogether about 12 acres of rhubarb. Only one species is in cultivation, and that I find to be R. rhaponticum. I have examined specimens of it sent to me by Mr. Rye, surgeon of Banbury, and to the Pharmaceutical Society by Mr. W. Bigg. Mr. Usher states that no other species was ever cultivated at Banbury; and that he cannot produce English rhubarb from the "Giant rhubarb," or any other sort. [For further details see Mr Bigg's Answers to Queries (drawn up by the author), and the author's Note on Banbury Rhubarb, in the Pharmaceutical Journal, vol. vi. pp 73 74 and 76 .]
At Banbury, the rhubarb is obtained from roots of three or four years old. They are dug up in October or November, freed from dirt, deprived of their outer coat by a sharp knife, exposed to the sun and air for a few days, and dried on basketwork in drying-houses heated by stove-pipes or brick flues. Mr. Hayward accelerated the curing process by scooping a hole in the largest pieces; and dried both these; and the smaller pieces strung on packthread, and hung in a warm room.
The root-stock yields the trimmed English rhubarb; the root-branches yield the cuttings or stick English rhubarb. The produce of the process of trimming is called raspings, and serves for powdering.
Trimmed or dressed English rhubarb is the kind frequently observed in the show-bottles of druggists' windows, and was formerly sold in Cheapside and the Poultry for "Turkey rhubarb," by persons dressed up as Turks. It occurs in various-sized and shaped pieces, which are trimmed and frequently perforated, so as to represent foreign rhubarb; [Specimens in the Russian or Dutch style of trimming, in the Chinese or East India style of trimming, and of small trimmed (pieces like truncated cones) and fine trimmed Banbury rhubarb, are contained in the museum of the Pharmaceutical Society.] some of the pieces are cylindrical in their form, and are evidently segments of cylinders; others are flat. This kind of rhubarb is very light, spongy (especially in the middle of the large flat pieces), attractive of moisture, pasty under the pestle, and has a reddish or pinkish hue not observed in the Asiatic kind. Internally it has usually a marbled appearance; the streaks are pinkish, parallel, and have a radiated disposition;_ and in the centre of some of the larger pieces the texture is soft and woolly, and may be easily indented by the nail. Its taste is astringent and very mucilaginous; it is not at all, or only very slightly, gritty tinder the teeth; its odour is feeble, and more unpleasant than either the Russian or East Indian kinds. The microscope discovers in it, for the most part, very few crystals of oxalate of lime.
The common stick English rhubarb (called at Banbury the cuttings) occurs in angular or roundish pieces, of about five or six inches long, and an inch thick. When fractured it presents the radiated appearance, and the red-coloured streaks of the kind last mentioned. Its taste is astringent, but very mucilaginous- it is not gritty under the teeth; it breaks very short.
English rhubarb is extensively employed by druggists to adulterate the powder of Asiatic rhubarb.
12. French rhubarb (Radix Rhei Gallici).—This kind of rhubarb is procured from Rheum Rhaponticum, undulatum, and especially compactum. [Guibourt, op. supra cit.] These are cultivated at Rheumpole, a place not far from Lorient, in the department of Morbihan. Rheum palmatum is no longer cultivated there. Through the kindness of Professor Guibourt, I possess two kinds of French rhubarb. One of these he calls flat, and is probably the produce of R. rhaponticum; the other be terms round, and is the produce of R. compactum.
Composition.—Few, if any, articles of the materia medica have been so frequently the subject of chemical investigation as rhubarb. Many chemists have submitted it to examination for the purpose of discovering all its proximate principles. Among these, may be mentioned Schrader [Berlinisches Jahrbuch f. d. Pharmacie auf das J. 1807, p. 123.] in 1807, N. E. Henry [Bull. de Pharm. vi. 87, 1814.] in 1814, Brande [Quart. Journ. of Science, vol. x. p. 288, 1821.] in 1821, Hornemann [Berl. Jahrb. Bd. xxiii. p 252, 1822.] in 1822, Peretti [Journ. de Pharm. xiv. 536, 1828.] in 1826, Buchner and Herberger [Buchner's Repertor. Bd. xxxviii. p 337, 1831.] in 1831, Lucae [Ibid für 1834, p. 78.] in 1833, O. Henry [Journ. de Pharm. xxii. 393, 1836.] in 1836, Brandes [Pharm Central-Blatt für 1836, p. 482.] in 1836, and Schlossberger and Doepping in 1844. [Ann. der Chem. u. Pharm. Bd. 1. p. 196, 1814; and Pharm. Journal, vol. iv. p. 136, 1811.]
But several of the more important chemical examinations of rhubarb have been made with the view chiefly of discovering the one or more active principles of rhubarb. Among these I include the investigations of Trommsdorff, [Journ. de Pharm. iii. 1, p. 106.] Pfaff, [Syst. d. Mat. Med. Bd. iii. p. 23. 1814; and Bd. vi. p. 308, 1821.] Nani, [Biblioth. Univ. xxxiii. 232.] Caventou, [Journ. de Pharm. t. xii. p. 22. 1826.] Carpenter, [Philadelphia Journal of Pharmacy, vol. i. p. 139.] Dulk, [Arch. d. Pharm. Bd. xvii. p. 26; also, Pharm. Central-Blatt für 1839, p. 102.] and especially of Schlossberger and Doepping, before quoted.
One hundred grains of the finest Russian rhubarb, according to Mr. Brande, lost 44.2 grs. by being repeatedly digested in alcohol (sp. gr. 0.815). By evaporation, the alcoholic solution yielded a residue of 36 grains (the loss 8.2 grs. may be ascribed to water), of which 10 grains (resin 1) were insoluble in water.
The rhubarb left after the action of alcohol weighed, when dried at 212° F., 55.8 grs. It yielded to water 31 grs. (gum?) The insoluble residue, weighing 24.8 grs., must have consisted of woody fibre, oxalate of lime, &c.
|Hormenann's Analyses.||Lucae's Analysis.|
|Russian.||English [Chinese?]||Sicilian [English?]||Rheum Emodi.|
|Bitter principle of Pfaff||16.042||14.375||10.156||4.220|
|Yellow colouring matter of Henry||9.583||9.166||2.187||7.500|
|Astringent extractive||14.687||16.458||10.417||6 158|
|Substance extracted by potash lye||28.333||30.416||41042||55.833|
|Oxalic acid||1.042||0.833||. . .||1 302|
|Moisture||3.333||3.125||6.042||. . .|
|Rhaponticin||. . .||. . .||1.042||. . .|
|Starch||. . .||. . .||14.583||. . .|
|Loss (water and odorous matter?)||0.939||0 629||1.614||1.604|
|The woody fibre being incinerated, yielded||The quantities of potash, lime, alumina, and magnesia, were too small to be accurately determined.|
|Potash||trace||trace||. . .|
|Carbonate of magnesia||0.208||0.208||0.208|
|Alumina with oxide of iron||0.208||0.208||0.572|
|Carbonate of lime||5.883||7.083||3.854|
|Ashes||8.873||8.123||. . .||4.997|
|Brande's Analysis||Schlossberger and Doepping's Analysis|
|(Chinese Rhubarb)||(Moscow and Chinese Rhubarb)|
|Pure rhabarberic acid||2.0||1. Chrysophanic acid.|
|Impure rhabarberic acid||7.5||2. Three resins (aporetine, phaeoretine, and erythroretine.)|
|Gallic acid, with some rhabarberic acid||2.5||3. Extractive matter.|
|Tannin||9.0||4. Tannic acid.|
|Colouring extractive||3.5||5. Gallic acid.|
|Uncrystallizable sugar, with tannin||11.0||6. Sugar.|
|Starch and pectic acid||4.0||7. Pectine.|
|Malate and gallate of lime||1.1||8. Oxalate of lime.|
|Oxalate of lime||11.0||9. Ashes (containing potash, soda, silica and sand, traces of sesquioxide of iron, phosphate of lime and magnesia, sulphuric, muriatic (chlorine), phosphoric and carbonic acids.|
|Sulphate of potash, and chloride of potassium||1.5|
|Phosphate of lime with oxide of iron||0.5|
Schlossberger and Doepping conclude that the flavour, relation to chemical reagents, and therapeutical properties of rhubarb, depend on the conjoint operation of the resin, the colouring matter, and the extractive; modified perhaps in some degree by the other ingredients.
1. Odorous Matter of Rhubarb (Volatile Oil?).—In none of the analyses of rhubarb is any mention made of a distinct odorous principle; yet it appears to me that such must exist As the colour and odour bear no proportion to each other in different kinds of rhubarb, it is tolerably clear, that they cannot depend on one and the same principle. The odorous principle is probably a volatile oil, but it has not hitherto been isolated. A few years since, Dr. Bressy announced to the Académie de Médecine that he had separated it, but the committee appointed to repeat his experiments was unable to procure it by his process. [Dict. des Drog. t. iv. p. 425.] Zenneck [Pharm. Central-Blatt für 1832, S. 237.] says that the rhubarb odour is imitated by a mixture of nitric acid, aloes, and chloride of iron.
2. Yellow Crystalline Granular Matter of Rhubarb. Chrysophanic Acid (so called from χρυσός, gold, and φαίνοο, I shine); Rheic Acid. C10H8O3. Found in Russian and Canton rhubarb; in the roots of Rheum Rhaponticum arid Rumex obtusifolius; and in Parmelia parietina (see ante, p. 69). In the pure or more or less impure state, it has been long known under the names of rhabarbaric acid, rheumin, rhabarberin, and rhein. It may be procured from rhubarb by means of ether in Robiquet's displacement apparatus.
Pure chrysophanic acid is a beautiful, clear, yellow, odourless, and tasteless substance, which separates in granular masses, and shows little disposition to crystallize. It is tolerably soluble in hot rectified spirit of wine; not very soluble in ether, even when boiling; and almost insoluble in cold water, but more soluble in boiling water. Heated, it evaporates, emits yellow fumes which condense and form yellow flocculi, and at the same time a part becomes carbonized. It dissolves in alkalies, producing a beautiful red colour; if the potash solution be evaporated to dryness, the red colour changes to violet, and then to a beautiful blue. It dissolves in oil of vitriol, forming a beautiful red solution, from which water precipitates yellow flocculi.
3. Resins. According to Schlossberger and Doepping, rhubarb contains three resins, soluble in alcohol, but insoluble in water.
a. Aporetine (from άπο, from, and ρητίνη, resin) is a product or deposit of the resin of rhubarb. It is black and shining when dry; slightly soluble in hot spirit, ether, cold and hot water; very soluble in ammonia and potash.
6. Phaoretine (from φαιός, red brown, and ρητίνη); Brown resin of rhubarb. C16H8O7. It is yellowish brown, very slightly soluble in water and ether; very soluble in spirit and its alkalies, and may be thrown down from the latter solution by the mineral acids.
y. Erythoretine (from εγηθόσ, red, and ρητίνη); Red resin of rhubarb. C19H9O7. It is yellow, soluble in ether, very soluble in alcohol; forms rich purple combinations with potash and ammonia, which are very soluble in water. To this resin, as well as to chrysophanic acid, rhubarb chiefly owes its colour.
4. Bitter Principle; Extractive? Rhubarb contains a bitter principle; but most of the substances which have been announced as the bitter principle of rhubarb, under the name of caphopicrite (? from καφέω, I exhale, and πικγός, bitter), or rhabarberin, are themselves compounded of two or more principles. Schlossberger and Doepping describe the extractive matter of rhubarb as having a bitter taste, but not the flavour of rhubarb.
5. Astringent Matter (Tannic and Gallic adds) —The red veins are the seat of the astringent matter. This is proved by brushing the cut surface of rhubarb with a weak solution of a ferruginous salt; the red veins only undergo a change of colour.
6. Indifferent Substances.—Rhubarb contains a considerable quantity of starch and pectine or vegetable jelly. The starch consists of small grains, with a very distinct nucleus or hilum, and arranged in groups, each of 2, 3, or more grains. Sugar also may be detected by Trommer's test and fermentation (see ante, p. 150). Cellulose and mucilage also are present.
7. Oxalate of Lime.—The conglomerate raphides before noticed (see ante, p. 426) are crystals of oxalate of lime. They may be separated in great abundance by boiling Russian or China rhubarb in water until the cohesion of the tissue is completely destroyed. When the decomposed tissue is well shaken with water, the crystals fall to the bottom of the vessel. Heated to redness, they are changed into carbonate of lime. A solution of them in diluted nitric acid, or a solution obtained by boiling the crystals with a solution of carbonate of soda, forms, with nitrate of silver, a white precipitate (oxalate of silver), which explodes when heated. It has been already stated that the late Mr. Edwin Quekett obtained from 35 to 40 per cent, of oxalate of lime from Russian rhubarb.
8. Rhaponticin.—A yellow, crystallizable, odourless, tasteless substance, obtained from the root of European (English?) rhubarb. It is insoluble in cold water,ether, and the volatile oils, but soluble in 24 times its weight of boiling water, and twice its weight of absolute alcohol. [Berzelius, Traité de Chim. vi. 205.]
Chemical Characteristics.—If the powder of rhubarb be heated in a glass capsule over a lamp, an odorous yellow vapour (oil? or resin with chrysophanic acid) is obtained, which communicates a red colour to a solution of caustic potash. The aqueous infusion of rhubarb is rendered green by the sesquichloride of iron (tanno-gallate of iron); with a solution of gelatin it yields a copious yellow precipitate (tannate of gelatin), which is dissolved on the application of heat, or by the addition of an excess of gelatin; with a solution of disulphate of quinia, a yellowish precipitate (tannate of quinia); with the alkalies (potash, soda, and ammonia), a red-coloured solution (soluble alkaline chrysophanates); with lime-water, a reddish precipitate (chrysophanate of lime); with the acids (the acetic excepted), precipitates; and with various metallic solutions (as of acetate of lead, protochloride of tin, protonitrate of mercury, and the nitrate of silver), precipitates (principally metallic chrysophanates and tannates).
Distinguishing characteristics of rhubarb and turmeric.—Paper stained by a strong decoction of tincture of rhubarb is not affected by boracic acid, or by the borates rendered acid, whereas turmeric paper is reddened by these agents. [Faraday, Quart. Journ. of Science, vol. vi. p. 152.] Hence the presence of turmeric in powdered rhubarb may be detected by this means.
Differential characteristics of the commercial sorts of rhubarb.—All the different commercial sorts of rhubarb contain the same constituents, but in different proportions; hence the differential characteristics are founded on relative or comparative differences, not on absolute ones. English rhubarb usually contains a smaller quantity of crystals of oxalate of lime, and a larger quantity of starch. It, therefore, is less gritty between the teeth. In general, a decoction of Russian, Dutch-trimmed, or of China rhubarb, becomes, with a solution of iodine, greenish-blue (iodide of starch) : after a few minutes the colour disappears, and no iodine can be detected in the liquor by starch, unless nitric acid be previously added. A decoction of English rhubarb, however, is rendered, by a solution of iodine, intensely blue (iodide of starch), the colour not completely disappearing by standing. These peculiarities, however, are not constant. Some specimens of Russian rhubarb, however, contain so much starch that they react on iodine, like those of English rhubarb.
Physiological Effects, α. On Animals.—On the solipedes rhubarb acts as a tonic, confining its action principally to the stomach, whose digestive power it augments. On the carnivora it operates, in doses of half a drachm, in the same way; but, in doses of several drachms, as a purgative. On the larger herbivora it may be given to the extent of several ounces without causing purgation. [Moiroud, Pharm. Vétér. p. 260.] Tiedemann and Gmelin [Versuche ü. d. Wege auf welch. Subst. aus d. Magen u. Darmk. gelang. S. 10-12. ] detected it by its yellow colour in the serum of the blood of the mesenteric, splenic, and portal veins, and in the urine of dogs to which rhubarb had been administered by the mouth. They failed to recognize it in the chyle.
β. On Man.—In small doses (as from four to eight grains) it acts as an astringent tonic, its operation being principally or wholly confined to the digestive organs. In relaxed conditions of these parts it promotes the appetite, assists the digestive process, improves the quality of the alvine secretions, and often restrains diarrhoea. In large doses (as from a scruple to a drachm) it operates, slowly and mildly, as a purgative, sometimes causing slight griping. It never inflames the mucous membrane of the alimentary canal, as jalap, scammony, colocynth, and some other drastic purgatives are capable of doing. The constipation which follows its cathartic effect has been ascribed to the operation of its astringent matter. In febrile complaints and inflammatory diseases it sometimes accelerates the pulse, and raises the temperature of the body; whence the impropriety of its use in these cases.
Under the use of rhubarb the secretions, especially the urine, become coloured by it. According to Heller, the colour which the urine acquires under the employment of this medicine depends on the acid or alkaline condition of this secretion; if acid, it is yellow; if alkaline, it becomes reddish-yellow or blood-red. From Schlossberger's experiments, [Pharmaceutical Journal, vol. viii. p. 190, 1818.] it appears that the colour is communicated to the urine by the phaeoretine and erythroretine, and not by the chrysophanic acid, which, when pure, neither operates on the bowels nor colours the urine. Urine coloured by rhubarb stains the linen, and is reddened by caustic potash.
The cutaneous secretion (especially of the arm-pits) also becomes coloured under the use of rhubarb. The milk of nurses who have taken it is said to acquire a purgative property.
Rhubarb has for a long period been considered to possess a specific influence over the liver, to promote the secretion of bile, and to be used in jaundice. These opinions, which, as Dr. Cullen [Mat. Med.] correctly observed, have no foundation either in theory or practice, arose from the absurd doctrine of signatures.
Considered in relation to other medicinal agents, rhubarb holds an intermediate rank between the bitter tonics on the one hand, and the drastics on the other. From the first it is distinguished by its purgative qualities; from the latter, by its tonic operation and the mildness of its evacuant effects. As a purgative, it is perhaps more closely allied to aloes than to any other cathartic in ordinary use; but is distinguished by its much milder operation, and its want of any specific action on the large intestines.
The comparative power of the several kinds of rhubarb has scarcely been ascertained with precision. The remarks above made apply to the Russian and Chinese varieties, whose power is about equal. From experiments made by Dr. Parry, at the Bath Hospital, it appears that the purgative qualities of the English rhubarb are scarcely so strong as those of the Russian and Chinese varieties; but the difference is not great. [Stephenson and Churchill, Med. Bot.] For several years past, English rhubarb has been exclusively employed at the London Hospital; and no complaints have been made respecting its operation. Himalayan rhubarb is, according to Dr. Twining, [Trans. Med. and Phys. Soc. of Calcutta, vol. iii. p. 441.] almost equal to Russian rhubarb in its purgative effects; but is less aromatic, though more astringent.
Uses.—The remedial value of rhubarb depends on the mildness and safety of its operation, and on its tonic and astringent influence over the alimentary canal.
1. As a purgative.—There are many cases in which the above-mentioned qualities render rhubarb peculiarly valuable as a purgative. In mild cases of diarrhoea it sometimes proves peculiarly efficacious, by first evacuating any irritating matter contained in the bowels, and afterwards acting as an astringent. Given at the commencement of the disease, it is a very popular remedy; and though doubtless it is often employed unnecessarily (since, as Dr. Cullen has justly observed, in many cases no further evacuation is necessary or proper, than what is occasioned by the disease), yet it rarely, if ever, does harm. Sulphate of potash is a very useful adjunct to it, and promotes its purgative operation. Antacids (as chalk or magnesia) are frequently conjoined with it. It is not fitted for inflammatory or febrile cases. As an infant's purgative it is deservedly celebrated. It is well adapted for a variety of children's complaints; but is peculiarly adapted to scrofulous subjects, and those afflicted with enlargement of the mesenteric glands, accompanied with tumid belly and atrophy. Magnesia, sulphate of potash, or calomel may be associated with it, according to circumstances. For an ordinary purgative in habitual costiveness it is scarcely adapted, on account of the constipation which follows its purgative effect.
2. As a stomachic and tonic.—In dyspepsia, accompanied with a debilitated condition of the digestive organs, small doses of rhubarb sometimes prove beneficial, by promoting the appetite and assisting the digestive process. In scrofulous enlargement of the lymphatic glands, in children, rhubarb, in small doses, is often combined with mercurial alteratives (as the hydrargyrum cum cretâ), or with antacids (as magnesia or chalk), and frequently with apparent advantage.
3. As an external application.—Sir Everard Home [Pract. Observ. on the Treatment of Ulcers, p. 96, 1801.] used it as a topical application to promote the healing of indolent non-painful ulcers. The powder is to be lightly strewed over the ulcer, and a compress applied. In irritable ulcers an eighth part of opium is to be added. When applied to large ulcers it has produced pretty active purging. [Arnemann, Chirurg. Arzneim. 6ste Aufl. S. 224.] The powder of rhubarb, incorporated with saliva and rubbed on the abdomen, proves purgative. [Alibert, Nouv. Elem. de Thérap. t. ii. p. 275, et seq. 5me. éd.]
Administration.—The powder of Russian or China rhubarb may be exhibited, as a stomachic and tonic, in doses of from five to ten grains; as a purgative, from a scruple to a drachm. The dose of indigenous rhubarb should be about twice as j much as the above.
"By roasting it with a gentle heat, till it becomes friable [rheum torrefactum], its cathartic power is diminished, and its astringency supposed to be increased," (Lewis.)
1. INFUSUM RHEI, L. E. D. [U. S.]; Infusion of Rhubarb.—(Rhubarb, sliced [in coarse powder, E.], ʒiij [℥j, E.; ʒij, D.]; Boiling [distilled, L.] Water Oj [℥ix, D.; f℥xviij, E.]; [Spirit of Cinnamon f℥ij, E.]. Macerate for two [one hour, D.] hours in a lightly-covered vessel, and strain [through linen or calico, E].)— [The product should measure about eight ounces, D.] [The U. S. Pharm. directs Rhubarb, bruised, ʒi; Boiling Water Oss. Digest for two hours in a covered vessel, and strain.] Boiling water extracts from rhubarb chrysophanic acid, resin, tannin, gallic acid, sugar, extractive, and starch. As the liquor cools, it becomes turbid. Infusion of rhubarb is stomachic and gently purgative. It is usually employed as an adjunct to, or vehicle for, other mild purgatives or tonics. The alkalies or magnesia are sometimes conjoined. The stronger acids, and most metallic solutions, are incompatible with it. Dose, fʒj to f℥ij.
2. TINCTURA RHEI, E. [U.S.]; Tincture of Rhubarb.—(Rhubarb, in moderately fine powder, ℥iijss [℥iij, U. S.]; Cardamom Seeds, bruised, ℥ss; Proof Spirit [Diluted Alcohol, U. S.] Oij. Mix the rhubarb and cardamom seeds, and proceed by the process of percolation, as directed for tincture of cinchona. This tincture may also be prepared by digestion.)—The alcoholic tincture of rhubarb contains chrysophanic acid, tannin, resin, and uncrystallizable sugar. Cordial, stomachic, and mildly purgative. Dose, as a stomachic, fʒj to fʒiij; as a purgative, f℥ss to f℥j.
3. TINCTURA RHEI COMPOSITA, L. D.; Compound Tincture of Rhubarb.—(Rhubarb, sliced, ℥ijss [℥iij> D.]; Liquorice, bruised, ʒvi [℥ss, D.]; Saffron ʒiij [ʒij, D.]; [Ginger, bruised, ʒiij, L.; Cardamom Seeds ℥i, D.]; Proof Spirit Oij. Macerate for seven [fourteen, D.] days, then express and strain.)—Cordial, stimulant, stomachic, and mildly purgative. A popular remedy in various disordered conditions of the alimentary canal, especially at the commencement of diarrhoea, also in flatulent colic. It is a very useful adjunct to purgative mixtures, in cases in which the use of a cordial and stomachic cathartic is required. Dose, as a stomachic, fʒj to fʒiij; as a purgative, f℥ss to f℥jss.
4. TINCTURA RHEI ET ALOES, E. [U.S.]; Tincture of Rhubarb and Aloes.—(Rhubarb, in moderately fine powder, ℥iss; Socotrine or East Indian Aloes, in moderately fine powder, ʒvj; Cardamom Seeds, bruised, ʒv; Proof Spirit Oij. Mix the powders, and proceed as for the tincture of cinchona.)—[The U. S. Pharm. directs Rhubarb, bruised, ʒx; Aloes, in powder, ʒvi; Cardamom, bruised, ℥ss; Diluted Alcohol Oij. Macerate for fourteen days, express, and filter through paper.] A cordial and stomachic purgative, in doses of from f℥ss to f℥j.
5. TINCTURA RHEI ET GENTIANAE, E. [U.S.]; Tincture of Rhubarb and Gentian.—(Rhubarb, in moderately fine powder, ℥ij; Gentian, finely cut or in coarse powder, ℥ss; Proof Spirit [Diluted Alcohol, U. S.] Oij. Mix the powders, and proceed as directed for tincture of cinchona.)—Stomachic, tonic, and feebly purgative. Dose, as a tonic, fʒj to f℥iij; as a very mild purgative, f℥ss to f℥j.
6. VINUM RHEI, E. D. [U. S.]; Wine of Rhubarb.—(Rhubarb, in coarse powder, ℥v [℥iij, D.]; Canella, in coarse powder, ʒij [Proof Spirit f℥v, E.]; Sherry Oj and f℥xv [Oij, D.]. Digest for seven days, strain, express strongly the residuum, and filter the liquors.)—[Rhubarb, bruised, ℥ij; Canella, bruised, ʒj; Diluted Alcohol f℥ij; Wine Oj. Macerate for fourteen days, with occasional agitation, then express and filter through paper, U. S.]—Cordial, stomachic, and mildly purgative. Used in the same cases as the compound tincture of rhubarb. Dose, as a stomachic, fʒj to fʒiij; as a purgative, f℥ss to f℥j.
7. EXTRACTUM RHEI, L. E- D. [U. S.]; Extract of Rhubarb.—(Rhubarb, powdered, ℥xv; Proof Spirit Oj; Distilled Water Ovij. Macerate for four days with a gentle heat, afterwards strain, and set by, that the dregs may subside. Pour off the liquor, and evaporate it, when strained to a proper consistence, L.—The process of the Edinburgh and Dublin Colleges is as follows: Take of Rhubarb ℔j; Water Ov. Cut the rhubarb into small fragments; macerate it for twenty-four hours in three pints of the water, filter the liquor through a cloth, and express it with the hands or otherwise moderately; macerate the residuum with the rest of the water for twelve hours at least; filter the liquor with, the same cloth as before, and express the residuum strongly. The liquors, filtered again, if necessary, are then to be evaporated together to a proper consistence in a vapour-bath. The extract, however, is obtained of finer quality by evaporation in a vacuum with a gentle heat.)—[The U. S. Pharm. directs Rhubarb, in coarse powder, ℔j; Diluted Alcohol a sufficient quantity. Mix the Rhubarb with an equal bulk of coarse sand, moisten it thoroughly with Diluted Alcohol, and having allowed it to stand for twenty-four hours, put it into a percolator, and add Diluted Alcohol gradually until four pints of filtered liquor are obtained; then, by means of a water-bath, evaporate to the proper consistence.]
The Edinburgh and Dublin Colleges, it will be observed, employ no spirit in the above process. Great care is required in the preparation of this extract, as both the purgative and tonic properties of rhubarb are very apt to become deteriorated by the process. I have some extract prepared in vacuo more than twenty years ago, which still preserves the proper odour and flavour of rhubarb. The dose of extract of rhubarb, as a purgative, is from grs. x to ʒss.
[8. EXTRACTUM RHEI FLUIDUM, U. S.; Fluid Extract of Rhubarb.—(Take of Rhubarb, in coarse powder, ℥viij; Sugar ℥v; Tincture of Ginger ℥ss; Oil of Fennel, Oil of Anise, each ♏jv; Diluted Alcohol a sufficient quantity. To the Rhubarb, previously mixed with an equal bulk of coarse sand, add twelve fluidounces of Diluted Alcohol, and allow the mixture to stand for twenty-four hours. Transfer the mass to a percolator, and gradually pour upon it Diluted Alcohol until the liquid which passes has little of the odour or taste of the rhubarb. Evaporate the tincture thus obtained, by means of a water-bath, to five fluidounces; then add the sugar, and after it is dissolved, mix thoroughly with the resulting fluid extract, the tincture of ginger holding the oils in solution.—This is an excellent and efficient preparation in doses of fʒi—ij. It may be given to children in small doses. By addition to magnesia it constitutes an effective combination.]
9. PILULAE RHEI, E. [U.S.]; Rhubarb Pills.—(Rhubarb, in fine powder, nine parts; Acetate of Potash one part; Conserve of Red Roses five parts. Beat them into a proper mass, and divide it into five-grain pills.)—[Rhubarb, powdered, ʒvj; Soap ʒij. Make a mass with water, and divide into 120 pills. The soap renders them antacid, U. S.]—Stomachic and purgative. The acetate of potash is employed, I presume, to prevent the pills becoming hard by keeping. Each pill contains nearly three and a half grains of rhubarb.
10. PILULA RHEI COMPOSITAE, L. E. [U. S.]; Pilulae Rhei Compositae, D.; Compound Pills of Rhubarb.—(Rhubarb, powdered, ʒiv [twelve parts, E.]; Aloes powdered, ʒiij [nine parts, E.]; Myrrh, powdered, ʒij [six parts, E.]; Soap ʒss [six parts, E.]; [Oil of Caraway ♏xv, L., Oil of Peppermint one part, E.]; Treacle, q. s. [Conserve of Red Roses five parts, E.]. Mix them, and beat them into a proper mass [and divide this into five-grain pills. [The U. S. Pharm. directs Rhubarb, in powder, ℥i; Aloes, in powder, ʒvj; Myrrh, in powder, ℥ss; Oil of Peppermint fʒss. Beat them with water so as to form a mass, to be divided into two hundred and forty pills.] This pill may be also made without oil of peppermint, when so preferred, E. The Dublin College orders of Rhubarb, in fine powder, ℥iss; Hepatic Aloes, in fine powder, ʒix; Myrrh, in fine powder, Castile Soap, of each, ʒvi; Oil of Peppermint fʒi; Treacle, by weight, ℥ij.]—Tonic and mildly purgative. Dose, ℈j, or two to four pills.
11. PILULAE RHEI ET FERRI, E.; Pills of Rhubarb and Iron.—(Dried Sulphate of Iron four parts; Extract of Rhubarb ten parts; Conserve of Red Roses about five parts. Beat them into a proper pill mass, and divide into five-grain pills.)— Tonic. Dose, two to four pills.
12. PULVIS RHEI COMPOSITUS, E. D.; Compound Powder of Rhubarb.—(Magnesia, ℔j [℥vi, D.]; Ginger, in fine powder, ℥ij [℥i, D.]; Rhubarb, in fine powder, ℥iv [℥ij, D.]. Mix them thoroughly, and preserve the powder in well-closed bottles.)—A very useful antacid and mild stomachic purgative, especially adapted for children. Dose, for adults, ℈j to ℥ss; for children, gr. v to gr. x.
[13. SYRUPUS RHEI, U. S.; Syrup of Rhubarb.—(Take of Rhubarb, bruised, two ounces; Boiling Water a pint; Sugar two pounds. Macerate the rhubarb in the water for twenty-four hours and strain; then add the sugar, and proceed in the manner directed for syrup.)—This is a mild astringent and laxative, and may be used in bowel affections. The dose is from fʒj to f℥j.
14. SYRUPUS RHEI AROMATICUS, U. S.; Aromatic Syrup of Rhubarb; Spiced Syrup of Rhubarb.—(Take of Rhubarb, bruised, two ounces and a half; Cloves, bruised, Cinnamon, bruised, each half an ounce; Nutmeg, bruised, two drachms; Diluted Alcohol two pints; Syrup six pints. Macerate the rhubarb and aromatics in the diluted alcohol for fourteen days, and strain; then, by means of a water-bath, evaporate the liquor to a pint, and, while it is still hot, mix it with the syrup previously heated; or it may be made by displacement.)—This syrup is cordial, carminative, and slightly laxative. It is well adapted to weak and relaxed conditions of the bowels, as in chronic diarrhoea, dysentery, and infantile bowel complaints, with feeble action. The dose is fʒj to f℥ss.]