_Concerning the Opinion, that Mercury cures the Lues Venerea by the
evacuation it produces._
THERE are few medicines with regard to the operation of which all
practitioners are agreed. It is, however, by no means incumbent on him
who means to establish the truth of any one opinion to overturn every
hypothesis advanced on the same subject. But, as the arguments urged in
favour of any hypothesis will have much less weight when another is
previously believed to be true, and as the regulation of practice is, in
every case, to a certain extent, founded upon theory, no inconsiderable
advantage may be derived from overturning an ill-founded opinion,
especially when it is generally received. The theory of the action of
mercury, as well as of other substances, has afforded room for a
diversity of opinions. For the reasons mentioned above, then, although
it is by no means intended, that every opinion, with regard to the
operation of that medicine, should here be considered; yet, as it is a
very prevailing opinion, that the good effects obtained from mercury in
the cure of _lues venerea_, depend upon its action as an evacuant; and,
as a variety of seemingly strong arguments have been adduced in favour
of that hypothesis, it will be necessary to examine how far they are
sufficient to establish its truth.
In favour of the opinion, that mercury cures _lues venerea_ by acting as
an evacuant, the following arguments have been employed. It is alledged,
that the good effects obtained from mercury in the cure of this disease,
are in proportion to the evacuation which it produces; that the cure
produced by mercury depends more upon the stimulant power of the
preparation which is employed, than upon the quantity taken; and that
the same good effects are obtained from other evacuants as from mercury;
particularly, that the venereal disease is cured in a similar manner
from the employment of guaiac. The arguments here enumerated, if not the
only ones upon which this opinion is founded, are at least those which
are principally employed. To examine, then, how far these are well
founded, will be sufficient.
The first argument here adduced is, that the good effects of mercury are
proportioned to the evacuation which it produces. This assertion, if
allowed to be true, might, at first sight, appear to be a very strong
argument in favour of the theory here adopted. But it is strong in
appearance only; for, although it should be admitted, it in fact proves
nothing.
But, even previous to this, it might be made a question, how far what is
here assumed as a fact is well founded? And if it should appear, that
mercury does not cure _lues venerea_ in proportion to the evacuation
which it produces, a strong argument might from thence be brought
against this theory. But what may be said on this question will, with
greater propriety, occur when the objections to the theory come to be
adduced, than in attempting to refute and invalidate the arguments
brought in its favour. At present, it will be sufficient to show, that,
even allowing it to be true, it is no argument in favour of the
supposition.
If it be true, that mercury cures _lues venerea_ in proportion to the
evacuation it produces, it may indeed, with some degree of probability,
be concluded, that the evacuation and cure are not unconnected. And, if
the evacuation is not the cause of the cure, it might at least from
thence be inferred, that both of them depend upon the same cause; but it
no more, unquestionably, follows from thence, that the evacuation is the
cause of the cure, than that the cure produces the evacuation.
The degree of evacuation which, in any case, arises from the employment
of mercury, will, it is natural to imagine, be proportioned to the
quantity of active mercury which is introduced into the system. But, in
whatever way mercury acts in the cure of the venereal disease, it may
then be supposed to act most powerfully when it is present in the system
in most considerable quantity. In this point of view, then, the
evacuation which arises from the use of mercury is to be considered
merely as an index of the quantity of the medicine which is introduced
into the system in an active state; and the cure may be proportioned to
the evacuation, only as pointing out the degree in which the mercury
exists in the habit. Even supposing, then, that the foundation upon
which this argument is built were not to be called in question, yet,
taken in its greatest latitude, it is still at best but doubtful; and
from it no conclusion can be drawn in favour of the theory which it is
brought to support.
The second argument mentioned in proof of the supposition that mercury
acts, in the cure of _lues venerea_, as an evacuant, was, that the cure
produced by mercury depends more upon the stimulant power of the
preparation employed, than upon the quantity of mercury which is used.
This argument may be answered in the same manner with the preceeding. It
is indeed true, that different preparations of mercury, when used in
equal quantities, have by no means equal influence in the cure of _lues
venerea_. There is seldom an opportunity of observing what would be the
effects of the most stimulant preparations, as, in the venereal disease,
they are by no means in common use; and as, from their action on the
alimentary canal, they exert very violent effects, without entering the
circulating system. They, in general, operate very roughly, both as
emetics and purgatives; but it is not clear that, in the venereal
disease, any benefit has been obtained from their effects in either of
these ways. It can therefore by no means be allowed, that the foundation
of this argument, in its full extent, is strictly true. It cannot indeed
be denied, that some preparations of mercury, which possess a
considerable stimulant power, have a greater influence in the cure of
_lues venerea_, than several others which are less stimulant. So far,
then, the foundation upon which this argument is built, must be allowed
to be just, and its weight, as tending to establish this theory,
requires a refutation.
But, even admitting it to be just, without any reserve, still, no more
than from the former, can any conclusion be drawn from this in favour of
the theory which it is meant to support. It has already been observed,
that, in whatever way mercury operates in the cure of _lues venerea_,
its good effects may always be supposed to be proportioned to the
quantity of the medicine which enters the system in such a state as to
become active there. But the quantity of active mercury entering the
system can in no case be judged of from the quantity of the preparation
which is employed. One preparation of mercury much more readily admits
of a mixture with the animal fluids than another; in consequence of
this, it will find a more ready entrance into the system. And further,
this variety in the facility of access into the system, not only holds
in different preparations, but even in the same preparation at different
times.
In proof of the first of these propositions, we have a convincing
example in the difference which is observable between the effects
arising from the use of crude mercury, and of this metallic substance,
when no other means are used to render it active than simple
trituration. It is well known, that even a very inconsiderable quantity,
taken in this last way, will soon shew its effects at the most remote
excretories of the body; in the other, although swallowed to the
quantity of many pounds, it is a very rare occurrence that any effects
can be observed from which it can be concluded, that it has, in any
degree, entered the mass of circulating fluids.
But it was likewise alledged, that mercury, used at different times,
although given in equal quantities and in the same form, produces very
different effects. Crude mercury, as has already been observed, although
swallowed in considerable quantities, rarely produces any other effect
on the body, than what arises from the passage through the alimentary
canal. This, however, although generally, is not universally the case.
On some occasions, when taken in this way, it operates with as great
activity as when used in any other form; and, from many well attested
instances, it appears, that, by being swallowed even in a crude state, a
high salivation has been excited. In this we have an instance in which a
remarkable difference of effect arises from the employment of the same
preparation at different times. This difference cannot arise from the
quantity of mercury employed; for while, in some cases, no operation of
the nature here mentioned takes place from the use of a large quantity,
in others, it will be excited where an inconsiderable quantity only has
been taken. The difference of effects here observed, then, must be
ascribed to some other cause; and it is most reasonable to refer it to
particular accidents in the constitution at the time the medicine is
used. In these cases, where no operation takes place from its use, it
may be concluded, that the whole quantity of mercury swallowed has
passed through the alimentary canal in the same state in which it was
taken in. When, on the other hand, an operation upon the salivary
glands, or any other excretory remote from the alimentary canal, is
observed from the use of crude mercury, it may be concluded, that part
of the mercury, from some peculiarity in the habit at the time, such,
for example, as the presence of superabundant acid in the stomach, has
been brought into such a state as to be capable of entering the
circulating system. From these instances, then, it evidently appears,
that the facility with which mercury enters the system, admits of very
great variety. And from this a strong objection may be adduced against
the argument here brought to support the hypothesis that mercury cures
_lues venerea_ by its evacuant power.
It is alledged, that mercury cures _lues venerea_ by the evacuation it
occasions; because the good effects derived from its employment are
observed to be more in proportion to the stimulant power of the
preparation which is used, than to the quantity of mercury taken. The
data, however, here assumed by no means lead to the conclusion deduced
from thence. The most stimulant preparations of mercury, by their action
on the _primæ viæ_, are in general immediately expelled from the system.
When this happens, they have no influence in the cure of venereal
complaints. When they are not thus expelled, their nature is such that
they most readily enter the system. Their superior action, then, may be
accounted for without supposing that it depends on their producing the
most considerable evacuation.
From the facts as here stated, it indeed follows, that the good effects
obtained from mercury are greatest in those cases in which the mercury
enters the system in most considerable quantity. The evacuation, it is
true, is then likewise greatest. But this will unquestionably follow as
the necessary consequence of the presence of active mercury in the
system, and can by no means be concluded to be the cause of the cure.
The evacuation which occurs in this case, then, as was observed in the
objections adduced against the last argument, can be considered only as
an index of the quantity of active mercury which is present in the
system. The superior activity, therefore, which some stimulant
preparations possess, when compared with those of a milder nature, is by
no means a proof of the supposition that mercury cures _lues venerea_ by
means of the evacuation which it produces; and this argument, as well as
the former, may be set aside.
The third argument mentioned in favour of this theory, and the last
which we proposed to consider, is, that the same good effects, in the
cure of _lues venerea_, may be obtained from the employment of other
evacuants, as from that of mercury; and particularly, that the venereal
disease is cured in a similar manner by the use of guaiac.
This argument, if well founded, would indeed be a conclusive proof of
the theory, in support of which it is here adduced. Evacuation may be
occasioned by a great variety of other means besides mercury. The
influence of any discharge, as tending to cure _lues venerea_, will fall
more particularly to be considered in stating the objections against
this theory. A full answer, then, to the first part of this argument,
would at present be superfluous: But it may be observed, that it is by
no means a common practice to attempt the cure of _lues venerea_ by the
safest and most effectual evacuants now in use; and that, when evacuants
are employed for the cure of other diseases, while a venereal infection
at the same time exists in the system, it is never found to yield to
them. This first part of the argument, then, may be shortly answered, by
denying it to be true.
It is indeed true, that much benefit has been alledged to be obtained
from guaiac in the cure of the _lues venerea_. Experience, however, has
sufficiently demonstrated, that these testimonies are not altogether to
be relied upon. The influence of guaiac may perhaps be very considerable
in certain stages of _lues venerea_, when the malignity of the disease
is already overcome by means of mercury; or in particular climates,
where the nature of this infection seems to be in some degree different
from what it is in this country. But, how far the good effects of guaiac
are established by facts in this climate, and before a cure has been
attempted by mercury, is still a matter of great doubt. And, at any
rate, even the most sanguine advocates for the use of guaiac will allow,
that the good effects obtained from its use are by no means to be put in
competition with those which are derived from the employment of mercury.
But, even admitting all that has been said in favour of guaiac to be
strictly true, still it does not follow, that it cures the _lues
venerea_ by evacuation. Many medicines which operate much more
powerfully as evacuants have no such effect. And, what was formerly said
with regard to the cure of _lues venerea_, being proportioned to the
evacuation produced by mercury, may perhaps, with equal justice, be
applied to guaiac. It cannot be, with certainty, concluded, that the
evacuation in either case is to be looked upon as the cause of the cure,
since, in both, it may only be its concomitant. From this argument,
then, nothing can be inferred, which has any tendency to establish the
truth of the theory in support of which it is adduced.
Thus have we examined the different arguments used in favour of the
supposition, that mercury cures _lues venerea_ by acting as an evacuant.
And, from this examination, it appears, that they admit of satisfactory
answers. What has then been said in proof of the theory, can by no means
be considered as sufficient to establish its truth. But the
insufficiency of the arguments adduced in support of it, is not the only
reason for not adopting it. There are many objections to this
hypothesis, which would have been sufficient for rejecting it, even
supposing that the arguments brought to prove it had been such, that no
falacy in them could have been detected. That this theory, then, may,
with less hesitation, be set aside, it will be necessary to mention a
few of these objections.
It obviously occurs as a first objection to this theory, that
evacuation, from its nature, cannot easily be supposed capable of
producing a cure of _lues venerea_. The changes which evacuation may
produce upon the fluids of the body, can only be conceived to be of two
kinds. They must either depend on a diminution of the quantity of the
fluids, or on a change of their quality. But, it is not easy to conceive
how the effects of the _venereal virus_ should be removed, or on what
footing this virus should be expelled from the system, by either of
these changes, when induced by evacuation.
A mere diminution of the quantity of circulating fluids, is certainly
insufficient for the cure of _lues venerea_. The venereal matter, as
present in the body, must either be diffused through the whole mass of
fluids, or confined to particular parts only. If it be diffused through
the whole mass, the taint, even after the most considerable evacuations,
will remain equally strong in the fluids still left in the body. And, as
the venereal virus evidently possesses a power of assimulation, when in
the human system, the whole mass of fluids would soon return to its
former state. This being the case, then, it must be allowed, that an
inconsiderable diminution of quantity cannot reasonably be supposed to
counteract an infection which exists in the remaining mass.
If, on the other hand, the venereal poison be supposed to exist only as
a noxious matter in the body, when collected at particular parts, it is
equally difficult to conceive, how evacuation from its nature should
produce a cure. It never has been observed, that mercury particularly
encreases the discharge by those parts where the venereal matter appears
actually to exist. In almost every case where it is used only
internally, there is no encrease of evacuation by venereal ulcerations.
It cannot, however, be imagined, that a discharge which takes place by
the salivary glands or skin, will particularly evacuate what is lodged
in the genitals, or extremities. We may therefore, with certainty,
conclude that evacuation does not at least cure _lues venerea_ by any
change arising merely from a diminution of the quantity of circulating
fluids.
Evacuants may perhaps be alledged to operate in the cure of _lues
venerea_ in another manner. It may be supposed, that they remove the
distemper from a change which they produce in the quality of the
circulating mass. But, from the smallest consideration, it will appear,
that this supposition is equally unsatisfactory as the former. If, from
evacuation, a diminution takes place equally from every part of the mass
of circulating fluids, no change of quality will ensue. If, however,
this proportion is not properly observed, a change of quality will
indeed take place. But that change will consist merely in the diminution
of particular parts in a compound mass, and can never be supposed to
remove a contagious matter of any kind, even supposing it to be lodged
in the particular part of that mass thus diminished. Much less will it
remove an infectious matter uniformly diffused through the whole parts
of the compound mass, or existing as a morbid matter in particular parts
of the body only. From the nature of evacuation, then, whether it be
supposed to operate by a diminution of the quantity of circulating
fluids, or by any change it can produce in point of quality, it may
readily be concluded, that it is by no means fitted for the cure of
_lues venerea_.
Another and more conclusive objection against the supposition that
mercury cures _lues venerea_ by evacuation, is, that this disease is by
no means cured by evacuation taking place in an equal, or even in a
greater degree, from other causes. This, however, should of necessity be
the case, were the former supposition well founded. Effectually to
overturn this theory, then, it will be necessary only to establish the
truth of this assertion.
It cannot perhaps be alledged, that any fair trial has ever been made of
evacuation, instituted solely with a view to cure the venereal disease,
and that in such cases it has been found to fail. But, without any such
trial, there are sufficient arguments to shew, that for this purpose it
really is ineffectual.
_Lues venerea_ would never, upon its first introduction, have been
considered as so unconquerable a disease, could it have been cured by
evacuation. Various modes of evacuation were then in common use in
medicine, and considered as the most effectual means of cure in many
diseases. The venereal distemper, till the introduction of mercury,
resisted the power of almost all the medicines employed against it; and,
in some parts, it was at that time reckoned so incurable, that the
police of the country obliged the unhappy sufferers who laboured under
it to separate themselves from all intercourse with the rest of mankind.
While this was the condition of the distemper, is it to be imagined that
every method of cure was not tried? May we not, then, conclude, that,
upon the first introduction of this disease, evacuation, by every known
means, and carried to the greatest height, was had recourse to, but
without effect?
But, to prove that evacuation will not cure the distemper, it is
needless to travel back to the first periods of this disease, or to rest
the evidence even upon the highest probability. From what occurs in many
morbid cases, we have every day evident proof of the insufficiency of
any discharge for producing a cure of the venereal disease. _Lues
venerea_ often exists at the same time with diseases in which an
increase of natural evacuations takes place. None of these diseases,
whether the evacuation happens by the salivary glands, as in small-pox,
by stool, as in dysentery, or by the skin, as in intermittents, have
ever been found to break its force, much less to produce a perfect cure.
Besides what happens in natural evacuations, we have likewise proofs of
the insufficiency of artificial evacuations for the cure of this
disease. Although evacuation, at least by other means than by the use of
mercury, is never now employed as a cure for the venereal disease; yet
venereal complaints are often complicated with others, for which various
evacuations are proper. And while evacuations are, with success,
employed for the cure of these, it is found, that the venereal taint
either remains unchanged, or is even increased in force. It cannot here
be alledged, that the difference of effect depends upon the mode of
evacuation. On such occasions, every mode of evacuation has been tried
with equal want of success. Even salivation, which was long considered
as the only effectual discharge, when excited by other means than by
mercury, or even by mercury itself, when externally applied to the
organs secreting saliva, has not been found more effectual than other
modes of evacuation. In some cases, indeed, mercury received into the
mouth by steam, or otherwise, has had good effects; but these were
either to be accounted for from its application to the diseased part, or
from its introduction into the system. It is, then, sufficiently
evident, that evacuation, at least by other means than mercury, does not
cure _lues venerea_.
To this theory it may be urged as a third, and not less powerful
objection than any of the former, that where the evacuation arising from
the use of mercury in _lues venerea_ is the greatest, the cure is often
retarded; and that mercury never more frequently fails than in those
cases where it begins to evacuate upon its first introduction into the
system.
That these assertions are true, at least of the obvious discharge
produced by mercury, will not be refused by any advocate for its action
as an evacuant. To this, indeed, they may think it a satisfactory
answer, that the influence of mercury as an evacuant cannot be judged of
from the apparent discharge. It may be alledged, and indeed with some
appearance of reason, that the greatest discharge produced by mercury is
by insensible perspiration; that mercury, in consequence of this, is a
more powerful evacuant than many other medicines by which a greater
obvious evacuation is produced; and that it has the effect to increase
perspiration in a more remarkable degree, when it increases no other
discharge than when it induces the greatest obvious evacuation. But
although it cannot be denied, that the use of mercury does increase
insensible perspiration; and that evacuation in this way may, on some
occasions, be greater than what would arise from salivation or any other
obvious discharge; yet these facts by no means tend to any conclusion
which will remove the difficulty formerly stated. Nor can it from thence
be supposed, that mercury always evacuates most powerfully in those
cases where it produces the most successful cure.
The degree of evacuation which takes place from the employment of any
medicine cannot indeed, in every case, be ascertained by the obvious
discharge. But, where the judgment formed from this test would be
fallacious, the marks of inanition consequent upon the use of any
medicine are always certain tests for determining the degree of
evacuation. From these it is evident, that the suppositions here
advanced, that mercury operates more powerfully as an evacuant than any
other medicine, and that it always produces a greater discharge when it
acts by the skin, than when it affects the salivary glands, or any other
excretory, are entirely without foundation.
From the marks of inanition appearing in the system, it is
demonstratively proved, that, from a variety of other means, a greater
evacuation can be produced than from mercury. In such circumstances,
however, by mercury the venereal disease is cured, by these other
evacuants it is not. And farther, where the cure of _lues venerea_ has
been retarded by a salivation occurring early, or where no cure has
taken place after salivation has been continued for a considerable time,
there is every mark of a much higher degree of inanition than when the
disease has been removed by mercury without any sensible evacuation.
There can remain no doubt, then, that the cure of _lues venerea_ is by
no means in proportion to the evacuation which it produces. This,
however, should necessarily be the case, were the cure effected by
evacuation.
Upon the whole, then, from what has been said of this theory of the
action of mercury in the cure of the _lues venerea_, it appears, that
the cure can by no means be referred to the evacuation. The different
arguments adduced in favour of that theory, we have endeavoured to shew,
either proceed on wrong principles, or, although admitted in their
greatest latitude, can afford no ground for any conclusion to support
it. Evacuation, from its nature, whether supposed to operate by
diminishing the quantity of circulating fluids, or by any change it can
induce in their quality, can scarce be conceived to be a cause adequate
to the cure of _lues venerea_. Evacuation does not produce a cure of the
venereal disease, when it takes place in an equal, or even in a much
greater degree, from the employment of other medicines, than when the
disease is effectually removed from the use of mercury. And, _lastly_,
the venereal disease is never more effectually cured by mercury, than
when it is evident, from every mark by which the degree of evacuation
can be determined, that the evacuation arising from it is least
considerable. It may, therefore, with confidence be asserted, that
mercury does not cure _lues venerea_ by evacuation.
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