The _Croton Tiglium_ is a native of the island of Ceylon, and is found
in Malabar, China, Cochinchina, and the Molucca Islands. Every part of
the plant would seem to be endowed with medicinal activity; the _root_
acts as a drastic purgative, and when pulverized, and exhibited in the
dose of a few grains, is considered at Amboyna and Batavia, as a
specific for dropsy; the _wood_ (_lignum Pavanæ_) produces, when
administered in small doses, a diaphoretic effect, and in larger ones it
proves drastic; the _leaves_ are also purgative, and when dried and
powdered are supposed to afford an antidote against the bite of the
_cobra del Capella_. The _seeds_, however, are the parts which have been
more generally employed in medicine, the effects of which appear to have
been well known for nearly a thousand years.[A] They were early
introduced into Europe, and long known under the names of _Grana
Molucca_—_Tilii Grana_—and _Grana Tiglia_.[678] It appears that they
were at first very frequently administered, but their extreme acrimony
and violence,[679] and probably the accidents which arose from their
injudicious use, soon banished the article from medical practice; in
India, however these seeds are still employed as an effectual purgative,
after first undergoing the process of roasting, or baking, for the
purpose of removing the shell, rendering the nut pulverulent, and at the
same time of moderating the acrimonious qualities.[680] The expressed
oil of these seeds does not appear to have been obtained in a separate
form until a later period; Lemery speaks of it, and Geoffroy in
directing its dose cautions us against giving more than ʒj!—he probably
meant a drop. Its use has very lately been revived, and there can be
little doubt but that under proper restrictions, it may become a
valuable acquisition to the practitioner. The profession is indebted for
its late introduction, or rather revival, to Mr. E. Conwell, of the East
India Company’s Medical Service, on the Madras Establishment, who,[681]
having for many years prescribed it with advantage, introduced a
quantity of it for trial in London, through the medium of his friend,
Mr. Short, of Ratcliffe Highway.
QUALITIES. This expressed oil has a yellow colour, a faint odour, and an
acrid taste; these qualities however will be found to vary in different
samples; but the fact, as Dr. Nimmo[682] has justly observed, may be
fairly explained, without suspecting the existence of any fraud, by
supposing that the seeds have undergone a different degree of
torrefaction, in order to separate the oil from the farinaceous part.
CHEMICAL COMPOSITION. The recent experiments of Dr. Nimmo have very
satisfactorily shewn that this oil consists of 45 parts of an _Acrid
purgative principle_, and 55 of a fixed oil resembling that of olives,
and not possessed of any cathartic property. The acrid principle appears
to reside in a resinous matter soluble in alcohol and sulphuric æther,
and in volatile and fixed oils. I have lately repeated some of Dr.
Nimmo’s experiments on a recently imported sample of oil, and with
similar results. The acrid principle appears to bear a strong analogy to
that which I separated from elaterium, and as I gave to this latter
principle the term _Elatin_, it seems to me that we might with much
propriety, apply the name _Tiglin_ to the former, especially as it does
not appear to possess any of the characters and habitudes of a
salifiable basis; at all events the adoption of such a term will obviate
the necessity of circumlocution in our descriptions. SOLUBILITY. By
alcohol the oil undergoes a ready decomposition; the _Tiglin_ is
dissolved together with a very minute quantity of the oily part. Ether
and oil of turpentine dissolve the whole; a fact which enables us, by
digesting the seeds in these menstrua, to obtain the article in as
genuine, and certainly in a much more uniform, condition, than by the
processes of torrefaction and expression, as practised in India; for
this fact we are also indebted to Dr. Nimmo. MED. USES. As far as I have
been able to ascertain the fact, this oil does not appear to produce any
effects which cannot be commanded by other drastic purgatives; its value
depends upon the facility with which it may be administered; in some
cases it is amply sufficient to touch the tongue, in others, a drop or
two will be required. In maniacs, and in cases where the administration
of bulky medicines is extremely difficult, it would seem to offer a
decided advantage.[683] FORMS OF EXHIBITION. It has been usually given
in this country in the proportion of from one to two drops, in the form
of pills. Dr. Nimmo’s discovery with respect to the chemical composition
of the oil, very naturally suggested to him the mode of administering it
in the form of an alcoholic tincture, (_Tinctura Tiglii_,) and he has
found by experience that such a preparation furnishes the means of
readily apportioning the dose to the various circumstances of the case;
thus he found that in administering a tincture[684] in doses equivalent
to the number of drops decomposed, the same effects were produced as
have been attributed to the entire oil. ADULTERATIONS. Much has been
said upon the fraudulent admixture of this comparatively expensive
article with the cheaper fixed oils; and we believe with much truth; a
circumstance which will of necessity prevent the general use of the
article; and occasion very different reports with respect to its value
and activity. Dr. Nimmo however proposes a method of detecting such
adulteration, by a process suggested by the results of his experiments
upon its composition, and whose rationalé will be easily understood
after the chemical history that has been just presented.
“Let a very light phial be counterpoised in an accurate balance; pour
into it 50 grains of the suspected oil, add alcohol (which has been
previously digested[685] upon olive oil,) agitate them well, pour off
the solution and add more alcohol as before, until the dissolved portion
is diffused in such a proportion of alcohol that each half drachm
measure shall contain equal to one dose of the oil of _Tiglium_ for an
adult. By afterwards placing the phial near a fire, to evaporate what
remains of the alcohol in the bottle, _if the residuum be to that which
has been abstracted by the alcohol as_ 55 to 45, _the oil is genuine_.
If olive, or any other oil little soluble in alcohol, has been employed
as the adulterating agent, it is evident that the residuum will be in a
larger proportion; but should _Castor Oil_ have been employed for that
purpose, the proportion of the residuum will be smaller even than in the
genuine medicine.”