Adulteration-Linseed is very liable to adulteration with other seeds, especially when the commodity is scarce. The admixture in question is due in part to careless harvesting and in part to intentional. additions. In 1864 the impure condition of the linseed shipped to the English market had become so detrimental to the trade that the importers and crushers' founded an association called The Linseed Association of London, by which they bound themselves to refuse all linseed containing more than 4 per cent. of foreign seeds, and this step very rapidly improved the quality of the article.1 As the druggist has to purchase linseed meal, he must of necessity rely to some extent on the character of the oil-presser from whom he derives his supplies. The presence of the seeds of Cruciferæ (as rape and mustard) which is common, may be recognized by the pungent odour of the essential oil which they develope in contact with water. The introduction of cereals would also be easily discovered by iodine, which strikes no blue colour in a decoction of linseed. The microscope will also afford important aid in the examination of linseed cake or meal. ZYGOPHYLLEÆ. LIGNUM GUAIACI. Lignum sanctum; Guaiacum Wood, Lignum Vita; F. Bois de Gayac; G. Guaiakholz, Pockholz. Botanical Origin-This wood is furnished by two West Indian species of Guaiacum, namely: 1. G. officinale L., a middle-sized or low evergreen tree, with light blue flowers, paripinnate leaves having ovate, very obtuse leaflets in 2, less often in 3 pairs, and 2-celled fruits. It grows in Cuba, Jamaica (abundantly on the arid plains of the south side of the island), Les Gonaives in the N.W. of Hayti (plentiful), St. Domingo, Martinique, St. Lucia, St. Vincent, Trinidad, and the northern coast of the South American continent. This tree affords the Lignum Vitae of Jamaica (of which very little is imported), a portion of that shipped from the ports of Hayti, and probably the small quantity exported by the United States of Colombia. 2. G. sanctum L., a tree much resembling the preceding, but distinguishable by its leaves having 3 to 4 pairs of leaflets which are very obliquely obovate or oblong, passing into rhomboid-ovate, and mucronulate; and a 5-celled fruit. It is found in Southern Florida, the Bahama Islands, Key West, Cuba, St. Domingo (including the part called Hayti) and Puerto Rico, and is certainly the source of the small but excellent Lignum Vitæ exported from the Bahamas as well as of some of that shipped from Hayti. History-There can be no doubt but that the earliest importations of Lignum Vitae were obtained from St. Domingo, of which island, Oviedo 2 who landed in America in 1514 mentions the tree, under the name of Guayacan, as a native. He points out its fruits as yellow and 2 Natural Hystoria de las Indias, Toledo, 1526. fol. xxxvii. 1 Greenish in Year-Book of Pharmacy, 1871. 590; Pharm. Journ. Sept. 9, 1871. resembling two joined lupines, which could only be said with reference to G. officinale and would not apply to the ovoid, five-cornered fruits of G. sanctum. Oviedo appears however to have been aware of two species, one of which he found in Española (St. Domingo) as well as in Nagrando (Nicaragua), and the other in the island of St. John (Puerto Rico), whence it was called Lignum sanctum. The first edition of Oviedo was printed in 1526; but some years before this the wood must have been known in Germany, as is evident by the treatises written in 1517, 1518, and 1519 by Nicolaus Poll,1 Leonard Schmaus 2 and Ulrich von Hutten.3 The last which gives a tolerable description of the tree, its wood, bark, and medicinal properties was translated into English in 1533 by Thomas Paynel, canon of Merton Abbey, and published in London in 1536 under the title- Of the wood called Guaiacum that healeth the Frenche Pockes and also helpeth the goute in the feete, the stoone, the palsey, lepree, dropsy, fallynge ewyll, and other dyseases." It was several times reprinted. Description-The wood (always known in commerce as Lignum Vita) as imported consists of pieces of the stem and thick branches, usually stripped of bark, and often weighing a hundredweight each. It is remarkably heavy and compact. Its sp. gr. which exceeds that of most woods is about 1.3. Lignum Vitae is mostly imported for turnery, and the chips, raspings and shavings are the only form in which it is commonly seen in pharmacy. A stem 7 to 8 inches in diameter cut transversely exhibits a light-yellowish zone of sapwood about an inch wide, enclosing a sharply defined heartwood of a dark greenish brown. Both display alternate lighter and darker layers, which especially in the sapwood are further distinguished by groups of vessels. In this manner are formed a large number of circles resembling annual rings, the general form of which is evident, though the individual rings are by no means well defined. More than 20 such rings may be counted in the sapwood of a log such as we have mentioned, and more than 30 in the heartwood. The pithless centre is usually out of the axis. The medullary rays are not visible to the naked eye but may be seen by a lens to be very numerous and equidistant. The pores of the heartwood may be distinguished as containing a brownish resin, while those of the outermost layer of sapwood are empty. In the thickest pieces sapwood is wanting and even in stems of about a foot in diameter it is reduced to of an inch. It is of looser texture than the heartwood and floats on water, whereas the latter sinks, Both sapwood and heartwood owe their tenacity to a peculiar zigzag arrangement of the woody bundles. 1 De cura Morbi Gallici per Lignum Guayacanum libellus, printed in 1535 but dated 19 Dec. 1517, 8 pages 8°. 2 De Morbo Gallico tractatus, Salisburgi, November 1518,-reprinted in the Aphrodisiacus of Luisinus, Lugd. Bat. 1728. 383. -We have only seen the latter. 3 Ulrichi de Hutten equitis de Guaiaci medicina et morbo gallico liber unus, 4°. (26 chapters) Moguntiæ, 1519. The Lignum Vitae of Jamaica (G. officinale) and that of the Bahamas (G. sanctum), The sapwood is tasteless. The of which authentic specimens have been kindly placed at our disposal by Mr. G. Shadbolt, display the same appearance as well as microscopic structure. 5 Lignum Vitæ is much used for the wheels (technically "sheaves") of ships' blocks (pulleys) the circumference of which ought to consist of the white sapwood. It is also required for caulking mallets, skittle balls and for the large balls used in American bowling alleys, for which purposes it should be as sound and homogeneous as possible. heartwood has a faintly aromatic and slightly irritating taste, and when heated or rubbed emits a weak agreeable odour. The bark which was formerly officinal but is now almost obsolete, is very rich in oxalate of calcium and affords upon incineration not less than 23 per cent. of ash. It contains a resin distinct from that of the wood, and also a bitter acrid principle. Microscopic Structure-The wood consists for the most part of pointed, not very long, ligneous cells (libriform), traversed by one-celled rows of medullary rays. There are also thin layers of parenchymatous tissue, to which the zones apparent in a transverse section of the drug are due. The pitted vessels are comparatively large but not very numerous. The structure of the sapwood is the same as that of the heartwood, but in the latter the ligneous cells are filled with resin. The parenchymatous cells contain crystals of oxalate of calcium. Chemical Composition-The only constituent of any interest is the resin which the heartwood contains to the extent of about a fourth of its weight. The sapwood afforded us 0.91 and the heartwood 0-60 per cent. of ash. Commerce-Lignum Vitae varies much in estimation, according to size, soundness, and the cylindrical form of the logs. The best is exported from the city of Santo Domingo whither it is brought from the interior of the island. The quantity shipped from this port during 1871 was 1494 tons.1 That obtained from the Haytian ports of the same island is much less esteemed in the London market. Some small wood of good quality comes from the Bahamas, and an ordinary quality, also small, from Jamaica. From the latter island, the quantity exported in 1871 was only 14 tons; from the Bahamas in the same year 199 tons.3 Lignum Vitae was shipped from Santa Marta in 1872 to the extent of 115 tons.1 Uses-Guaiacum wood is only retained in the pharmacopoeia as an ingredient of the Compound Decoction of Sarsaparilla. It is probably inert, at least in the manner in which it is now administered.5 Adulteration-In purchasing guaiacum chips it is necessary to observe that the non-resinous sapwood is absent, and still more that there is no admixture of any other wood. A spurious form of the drug seems to be by no means rare in the United States." RESINA GUAIACI. Guaiacum Resin; F. Résine de Gayac; G. Guaiakharz. Botanical Origin-Guaiacum officinale L., see preceding article. History-Hutten in 1519 stated that guaiacum wood when set on fire exudes a blackish resin which quickly hardens, but of which he 1 Consular Reports presented to Parliament, Aug. 1872. 2 Blue Book-Island of Jamaica for 1871. 3 Blue Book for Colony of Bahamas for 1871. 4 Consular Reports, Aug. 1873. 746. 5 The ancient treatment of syphilis by guaiacum which gained for the drug such immense reputation, consisted in the administration of vast quantities of the decoction, the patient being shut up in a warm room and kept in bed.` 6 Schulz, in the (Chicago) Pharmacist, Sept. 1873. 7 Op. cit. at p. 93. knew no use. The resin was in fact introduced into medicine much later than the wood. The first edition of the London Pharmacopoeia in which we find the former named, is that of 1677. Production In the island of St. Domingo whence the supplies of guaiacum resin are chiefly derived, the latter is collected from the stems of the trees, in part as a natural exudation, and in part as the result of incisions made in the bark. In some districts as in the island of Gonave near Port-au-Prince, another method of obtaining it is adopted. A log of the wood is supported in a horizontal position above the ground by two upright bars. Each end of the log is then set on fire, and a large incision having been previously made in the middle, the melted resin runs out therefrom in considerable abundance. The resin is collected chiefly from G. officinale, which affords it in greater plenty than G. sanctum. Description-The resin occurs in globular tears an inch to 1 inch in diameter, but much more commonly in the form of large compact masses, containing fragments of wood and bark. The resin is brittle, breaking with a clean, glassy fracture; in thin pieces it is transparent and appears of a greenish brown hue. The powder when fresh is grey, but becomes green by exposure to light and air. It has a slight balsamic odour and but little taste, yet leaves an irritating sensation in the throat. The resin has a sp. gr. of about 12. It fuses at 85° C., emitting a peculiar odour somewhat like that of benzoin. It is easily soluble in acetone, ether, alcohol, amylic alcohol, chloroform, creasote, caustic alkaline solutions, and oil of cloves; but is not dissolved or only partially by other volatile oils, benzol or bisulphide of carbon. By oxidizing agents it acquires a fine blue colour, well shown when a fresh alcoholic solution is allowed to dry up in a very thin layer and this is then sprinkled with a dilute alcoholic solution of ferric chloride. Reducing agents of all kinds, and heat produce decoloration. An alcoholic solution may be thus blued and decolorized several times in succession, but it loses at length its susceptibility. This remarkable property of guaiacum was utilized by Schönbein in his well-known researches on ozone. Chemical Composition-The composition of guaiacum resin was ascertained by Hadelich (1862) to be as follows: If the mother liquor obtained in the preparation of the potassium salt of guaiaretic acid (vide infra) is decomposed by hydrochloric acid, and the precipitate washed with water, ether will extract from the mass Guaiaconic Acid, a compound discovered by Hadelich, having the formula C38H4010. It is a light brown, amorphous substance, fusing at 100° C. 1 We have to thank Mr. Eugène Nau of Port-au-Prince for the information given under this head, as well as for some interesting specimens. it is without acid reaction but decomposes alkaline carbonates, forming uncrystallizable salts easily soluble in water or alcohol. It is insoluble in water, benzol, or bisulphide of carbon, but dissolves in ether, chloroform, acetic acid or alcohol. With oxidizing agents it acquires a transient blue tint. Guaiaretic Acid, C20H2604, discovered by Hlasiwetz in 1859, may be extracted from the crude resin by alcoholic potash or by quick lime. With the former it produces a crystalline salt; with the latter an amorphous compound: from either, the liquid which contains chiefly a salt of guaiaconic acid, may be easily decanted. Guaiaretic acid is obtained by decomposing one of the salts referred to with hydrochloric acid, and crystallizing from alcohol. The crystals, which are soluble also in ether, benzol, chloroform, carbon bisulphide or acetic acid, but neither in ammonia nor in water, melt below 80° C. and may be volatilized without decomposition. The acid is not coloured blue by oxidizing agents. After the extraction of the guaiaconic acid there remains a substance insoluble in ether to which the name Guaiac Beta-resin has been applied. It dissolves in alcohol, acetic acid or alkalis, and is precipitated by ether, benzol, chloroform or carbon bisulphide in brown flocks, the composition of which appears not greatly to differ from that of guaiaconic acid. Guaiacic Acid, C12H1606, obtained in 1841 by Thierry from guaiacum wood or from the resin, crystallizes in colourless needles. Hadelich was not able to obtain more than one part from 20,000 of guaiacum resin. Hadelich's Guaiac-yellow, the colouring matter of guaiacum resin, first observed by Pelletier, crystallizes in pale yellow quadratic octohedra, having a bitter taste. Like the other constituents of the resin, it is not a glucoside. The decomposition-products of guaiacum are of peculiar interest. On subjecting the resin to dry distillation in an iron retort and rectifying the distillate, Guaiacene (Guajol of Völckel), CHO, passes over at 118° C. as a colourless neutral liquid having a burning aromatic taste. At 205°-210° C., there pass over other products, Guaiacol (or Pyroguaiacic Acid or Guaiacyl-hydride), C'HO2, and Kreosol, C8H1002. Both are thickish, aromatic, colourless liquids, which become green by caustic alkalis, blue by alkaline earths, and are similar in their chemical relations to eugenic acid. Guaiacol has been prepared synthetically by GorupBesanez (1868) by combining iodide of methyl, CH3I, with pyrocatechin, C6H6O2. The After the removal by distillation of the liquids just described, there sublime upon the further application of heat, pearly crystals of Pyroguaiacin, C8H40°, an inodorous substance melting at 180° C. same compound is obtained together with guaiacol by the dry distillation of guaiaretic acid. Pyroguaiacin is coloured green by ferric chloride, and blue by warın sulphuric acid. The similar reactions of the crude resin are probably due to this substance (Hlasiwetz). Beautiful coloured reactions are likewise exhibited by two new acids which Hlasiwetz and Barth obtained (1864) in small quantity together with traces of fatty volatile acids, by melting purified resin of guaiacum with potassium hydrate. One of them is isomeric with pyrocatechuic acid. Uses-Guaiacum resin is reputed diaphoretic and alterative. It is frequently prescribed in cases of gout and rheumatism. |