_Lignum sanctum_; _Guaiacum Wood_, _Lignum Vitæ_; F. _Bois de Gaïac_;
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, parapinnate 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 Vitæ 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 Vitæ were obtained from St. Domingo, of which island,
Oviedo[403] 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
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,[404]
Leonard Schmaus[405] and Ulrich von Hutten.[406] 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 gout in the feete, the stoone, the palsey, lepree, dropsy,
fallynge euyll, and other dyseases._” It was several times reprinted.
In the old pharmacy the products of destructive distillation of
guaiacum wood were known as _Oleum ligni sancti_. It must have
consisted of the substances which we mention further on in the
following article.
=Description=—The wood (always known in commerce as _Lignum Vitæ_) 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 Vitæ is mostly imported for turnery,[407] 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.
[403] _Natural Hystoria de las Indias_, Toledo, 1526. fol. xxxvii.
[404] _Decura Morbi Gallici per Lignum Guayacanum libellus_, printed in
1535 but dated 19 Dec. 1517, 8 pages 8°.
[405] _De Morbo Gallico tractatus_, Salisburgi, November
1518,—reprinted in the _Aphrodisiacus_ of Luisinus, Lugd. Bat. 1728.
383.—We have only seen the latter.
[406] _Ulrichi de Hutten equitis de Guaiaci medicina et morbo gallico
liber unus_, 4°. (26 chapters) Moguntiæ, 1519.
[407] It 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.
In the thickest pieces sapwood is wanting, and even in stems of about a
foot in diameter it is reduced to ⅕ 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 an extremely peculiar
zigzag arrangement[408] of the woody bundles. The sapwood is tasteless.
The 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.[409]
The Lignum Vitæ of Jamaica (_G. officinale_) and that of the Bahamas
(_G. sanctum_), of which authentic specimens have been kindly placed at
our disposal by Mr. G. Shadbolt, display the same appearance as well as
microscopic structure.[410]
=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 Vitæ 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;[411] 220 tons were exported in 1877 from Puerto Plata on the
northern coast of the island. The wood obtained from the Haytian ports
(of the western part of the same island) is much less esteemed in the
London market.
[408] It has been remarkably well pointed out already by Valerius
Cordus (_obiit_ 1544). See Gesner’s edition of his _Hist. Stirpium
Argentorat_., 1561. 191.
[409] See also Oberlin et Schlagdenhauffen, _Journ. de Pharm._ 28
(1878) 246 and plate vi.
[410] That of _Guaiacum arboreum_ DC. is apparently very different.
This tree, occurring in New Granada, has already been noticed
(1571-1577) by Francisco Hernandez (_Nova plantarum, animal, et
mineral. mexicanor. hist._, Romæ 1651, fol. 63) under the name of
_Guayacan_. He mentions its large umbels with yellow flowers, those of
Guaiacum officinale, the “_Hoaxacan_” or Lignum sanctum, being blue. In
the _Prodromus Floræ Neo-Granatentis_ (_Ann. Scienc. nat._ xv., 1872.
p. 361) J. E. Planchon also describes Guaiacum arboreum, known there as
_Guayacan polvillo_; its wood is of an almost pulverulent fracture.
[411] _Consular Reports_ presented to Parliament, Aug. 1872.
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;[412] from the Bahamas in the same
year 199 tons.[413] Lignum Vitæ was shipped from Santa Marta in 1872 to
the extent of 115 tons.[414]
Hamburg is also an important place for the wood under notice; in 1877
there were imported 22,404 centners from S. Domingo and 3551 centners
from Venezuela.
=Uses=—Guaiacum wood is only retained in the pharmacopœia as an
ingredient of the Compound Decoction of Sarsaparilla. It is probably
inert, at least in the manner in which it is now administered.[415]
=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.[416]