actions are associated, was too great before cold immersion, as in the hot
days of summer, and by that means the sensorial power was previously
diminished, we see the cause why the cold bath gives such present strength;
namely, by stopping the unnecessary activity of the subcutaneous vessels,
and thus preventing the too great exhaustion of sensorial power; which, in
metaphorical language, has been called _bracing_ the system: which is,
however, a mechanical term, only applicable to drums, or musical strings:
as on the contrary the word _relaxation_, when applied to living animal
bodies, can only mean too small a quantity of stimulus, or too small a
quantity of sensorial power; as explained in Sect. XII. 1.
3. This experiment of cold bathing presents us with a simple fever-fit; for
the pulse is weak, small, and quick during the cold immersion; and becomes
strong, full, and quick during the subsequent glow of heat; till in a few
minutes these symptoms subside, and the temporary fever ceases.
In those constitutions where the degree of inirritability, or of debility,
is greater than natural, the coldness and paleness of the skin with the
quick and weak pulse continue a long time after the patient leaves the
bath; and the subsequent heat approaches by unequal flushings, and he feels
himself disordered for many hours. Hence the bathing in a cold spring of
water, where the heat is but forty-eight degrees on Fahrenheit's
thermometer, much disagrees with those of weak or inirritable habits of
body; who possess so little sensorial power, that they cannot without
injury bear to have it diminished even for a short time; but who can
nevertheless bear the more temperate coldness of Buxton bath, which is
about eighty degrees of heat, and which strengthens them, and makes them by
habit less liable to great quiescence from small variations of cold, and
thence less liable to be disordered by the unavoidable accidents of life.
Hence it appears, why people of these inirritable constitutions, which is
another expression for sensorial deficiency, are often much injured by
bathing in a cold spring of water; and why they should continue but a very
short time in baths, which are colder than their bodies; and should
gradually increase both the degree of coldness of the water, and the time
of their continuance in it, if they would obtain salutary effects from cold
immersions. See Sect. XII. 2. 1.
On the other hand, in all cases where the heat of the external surface of
the body, or of the internal surface of the lungs, is greater than natural,
the use of exposure to cool air may be deduced. In fever-fits attended with
strength, that is with great quantity of sensorial power, it removes the
additional stimulus of heat from the surfaces above mentioned, and thus
prevents their excess of useless motion; and in fever-fits attended with
debility, that is with a deficiency of the quantity of sensorial power, it
prevents the great and dangerous waste of sensorial power expended in the
unnecessary increase of the actions of the glands and capillaries of the
skin and lungs.
4. In the same manner, when any one is long exposed to very cold air, a
quiescence is produced of the cutaneous and pulmonary capillaries and
absorbents, owing to the deficiency of their usual stimulus of heat; and
this quiescence of so great a quantity of vessels affects, by irritative
association, the whole absorbent and glandular system, which becomes in a
greater or less degree quiescent, and a cold fit of fever is produced.
If the deficiency of the stimulus of heat is very great, the quiescence
becomes so general as to extinguish life, as in those who are frozen to
death.
If the deficiency of heat be in less degree, but yet so great as in some
measure to disorder the system, and should occur the succeeding day, it
will induce a greater degree of quiescence than before, from its acting in
concurrence with the period of the diurnal circle of actions, explained in
Sect. XXXVI. Hence from a small beginning a greater and greater degree of
quiescence may be induced, till a complete fever-fit is formed; and which
will continue to recur at the periods by which it was produced. See Sect.
XVII. 3. 6.
If the degree of quiescence occasioned by defect of the stimulus of heat be
very great, it will recur a second time by a slighter cause, than that
which first induced it. If the cause, which induces the second fit of
quiescence, recurs the succeeding day, the quotidian fever is produced; if
not till the alternate day, the tertian fever; and if not till after
seventy-two hours from the first fit of quiescence, the quartan fever is
formed. This last kind of fever recurs less frequently than the other, as
it is a disease only of those of the temperament of associability, as
mentioned in Sect. XXXI.; for in other constitutions the capability of
forming a habit ceases, before the new cause of quiescence is again
applied, if that does not occur sooner than in seventy-two hours.
And hence those fevers, whose cause is from cold air of the night or
morning, are more liable to observe the solar day in their periods; while
those from other causes frequently observe the lunar day in their periods,
their paroxysms returning near an hour later every day, as explained in
Sect. XXXVI.
IV. Another frequent cause of the cold fits of fever is the defect of the
stimulus of distention. The whole arterial system would appear, by the
experiments of Haller, to be irritable by no other stimulus, and the
motions of the heart and alimentary canal are certainly in some measure
dependant on the same cause. See Sect. XIV. 7. Hence there can be no
wonder, that the diminution of distention should frequently induce the
quiescence, which constitutes the beginning of fever-fits.
Monsieur Leiutaud has judiciously mentioned the deficiency of the quantity
of blood amongst the causes of diseases, which he says is frequently
evident in dissections: fevers are hence brought on by great hæmorrhages,
diarrhoeas, or other evacuations; or from the continued use of diet, which
contains but little nourishment; or from the exhaustion occasioned by
violent fatigue, or by those chronic diseases in which the digestion is
much impaired; as where the stomach has been long affected with the gout or
schirrus; or in the paralysis of the liver, as described in Sect. XXX.
Hence a paroxysm of gout is liable to recur on bleeding or purging; as the
torpor of some viscus, which precedes the inflammation of the foot, is thus
induced by the want of the stimulus of distention. And hence the
extremities of the body, as the nose and fingers, are more liable to become
cold, when we have long abstained from food; and hence the pulse is
increased both in strength and velocity above the natural standard after a
full meal by the stimulus of distention.
However, this stimulus of distention, like the stimulus of heat above
described, though it contributes much to the due action not only of the
heart, arteries, and alimentary canal, but seems necessary to the proper
secretion of all the various glands; yet perhaps it is not the sole cause
of any of these numerous motions: for as the lacteals, cutaneous
absorbents, and the various glands appear to be stimulated into action by
the peculiar pungency of the fluids they absorb, so in the intestinal canal
the pungency of the digesting aliment, or the acrimony of the fæces, seem
to contribute, as well as their bulk, to promote the peristaltic motions;
and in the arterial system, the momentum of the particles of the
circulating blood, and their acrimony, stimulate the arteries, as well as
the distention occasioned by it. Where the pulse is small this defect of
distention is present, and contributes much to produce the febris
irritativa pulsu debili, or irritative fever with weak pulse, called by
modern writers nervous fever, as a predisponent cause. See Sect. XII. 1. 4.
Might not the transfusion of blood, suppose of four ounces daily from a
strong man, or other healthful animal, as a sheep or an ass, be used in the
early state of nervous or putrid fevers with great prospect of success?
V. 1. The defect of the momentum of the particles of the circulating blood
is another cause of the quiescence, with which the cold fits of fever
commence. This stimulus of the momentum of the progressive particles of the
blood does not act over the whole body like those of heat and distention
above described, but is confined to the arterial system; and differs from
the stimulus of the distention of the blood, as much as the vibration of
the air does from the currents of it. Thus are the different organs of our
bodies stimulated by four different mechanic properties of the external
world: the sense of touch by the pressure of solid bodies so as to
distinguish their figure; the muscular system by the distention, which they
occasion; the internal surface of the arteries, by the momentum of their
moving particles; and the auditory nerves, by the vibration of them: and
these four mechanic properties are as different from each other as the
various chemical ones, which are adapted to the numerous glands, and to the
other organs of sense.
2. The momentum of the progressive particles of blood is compounded of
their velocity and their quantity of matter: hence whatever circumstances
diminish either of these without proportionally increasing the other, and
without superadding either of the general stimuli of heat or distention,
will tend to produce a quiescence of the arterial system, and from thence
of all the other irritative motions, which are connected with it.
Hence in all those constitutions or diseases where the blood contains a
greater proportion of serum, which is the lightest part of its composition,
the pulsations of the arteries are weaker, as in nervous fevers, chlorosis,
and hysteric complaints; for in these cases the momentum of the progressive
particles of blood is less: and hence, where the denser parts of its
composition abound, as the red part of it, or the coagulable lymph, the
arterial pulsations are stronger; as in those of robust health, and in
inflammatory diseases.
That this stimulus of the momentum of the particles of the circulating
fluid is of the greatest consequence to the arterial action, appears from
the experiment of injecting air into the blood vessels, which seems to
destroy animal life from the want of this stimulus of momentum; for the
distention of the arteries is not diminished by it, it possesses no
corrosive acrimony, and is less liable to repass the valves than the blood
itself; since air-valves in all machinery require much less accuracy of
construction than those which are opposed to water.
3. One method of increasing the velocity of the blood, and in consequence
the momentum of its particles, is by the exercise of the body, or by the
friction of its surface: so, on the contrary, too great indolence
contributes to decrease this stimulus of the momentum of the particles of
the circulating blood, and thus tends to induce quiescence; as is seen in
hysteric cases, and chlorosis, and the other diseases of sedentary people.
4. The velocity of the particles of the blood in certain circumstances is
increased by venesection, which, by removing a part of it, diminishes the
resistance to the motion of the other part, and hence the momentum of the
particles of it is increased. This may be easily understood by considering
it in the extreme, since, if the resistance was greatly increased, so as to
overcome the propelling power, there could be no velocity, and in
consequence no momentum at all. From this circumstance arises that curious
phænomenon, the truth of which I have been more than once witness to, that
venesection will often instantaneously relieve those nervous pains, which
attend the cold periods of hysteric, asthmatic, or epileptic diseases; and
that even where large doses of opium have been in vain exhibited. In these
cases the pulse becomes stronger after the bleeding, and the extremities
regain their natural warmth; and an opiate then given acts with much more
certain effect.
VI. There is another cause, which seems occasionally to induce quiescence
into some part of our system, I mean the influence of the sun and moon; the
attraction of these luminaries, by decreasing the gravity of the particles
of the blood, cannot affect their momentum, as their vis inertiæ remains
the same; but it may nevertheless produce some chemical change in them,
because whatever affects the general attractions of the particles of matter
may be supposed from analogy to affect their specific attractions or
affinities: and thus the stimulus of the particles of blood may be
diminished, though not their momentum. As the tides of the sea obey the
southing and northing of the moon (allowing for the time necessary for
their motion, and the obstructions of the shores), it is probable, that
there are also atmospheric tides on both sides of the earth, which to the
inhabitants of another planet might so deflect the light as to resemble the
ring of Saturn. Now as these tides of water, or of air, are raised by the
diminution of their gravity, it follows, that their pressure on the surface
of the earth is no greater than the pressure of the other parts of the
ocean, or of the atmosphere, where no such tides exist; and therefore that
they cannot affect the mercury in the barometer. In the same manner, the
gravity of all other terrestrial bodies is diminished at the times of the
southing and northing of the moon, and that in a greater degree when this
coincides with the southing and northing of the sun, and this in a still
greater degree about the times of the equinoxes. This decrease of the
gravity of all bodies during the time the moon passes our zenith or nadir
might possibly be shewn by the slower vibrations of a pendulum, compared
with a spring clock, or with astronomical observation. Since a pendulum of
a certain length moves slower at the line than near the poles, because the
gravity being diminished and the vis inertiæ continuing the same, the
motive power is less, but the resistance to be overcome continues the same.
The combined powers of the lunar and solar attraction is estimated by Sir
Isaac Newton not to exceed one 7,868,850th part of the power of
gravitation, which seems indeed but a small circumstance to produce any
considerable effect on the weight of sublunary bodies, and yet this is
sufficient to raise the tides at the equator above ten feet high; and if it
be considered, what small impulses of other bodies produce their effects on
the organs of sense adapted to the perception of them, as of vibration on
the auditory nerves, we shall cease to to be surprised, that so minute a
diminution in the gravity of the particles of blood should so far affect
their chemical changes, or their stimulating quality, as, joined with other
causes, sometimes to produce the beginnings of diseases.
Add to this, that if the lunar influence produces a very small degree of
quiescence at first, and if that recurs at certain periods even with less
power to produce quiescence than at first, yet the quiescence will daily
increase by the acquired habit acting at the same time, till at length so
great a degree of quiescence is induced as to produce phrensy, canine
madness, epilepsy, hysteric pains or cold fits of fever, instances of many
of which are to be found in Dr. Mead's work on this subject. The solar
influence also appears daily in several diseases; but as darkness, silence,
sleep, and our periodical meals mark the parts of the solar circle of
actions, it is sometimes dubious to which of these the periodical returns
of these diseases are to be ascribed.
As far as I have been able to observe, the periods of inflammatory diseases
observe the solar day; as the gout and rheumatism have their greatest
quiescence about noon and midnight, and their exacerbations some hours
after; as they have more frequently their immediate cause from cold air,
inanition, or fatigue, than from the effects of lunations: whilst the cold
fits of hysteric patients, and those in nervous fevers, more frequently
occur twice a day, later by near half an hour each time, according to the
lunar day; whilst some fits of intermittents, which are undisturbed by
medicines, return at regular solar periods, and others at lunar ones; which
may, probably, be owing to the difference of the periods of those external
circumstances of cold, inanition, or lunation, which immediately caused
them.
We must, however, observe, that the periods of quiescence and exacerbation
in diseases do not always commence at the times of the syzygies or
quadratures of the moon and sun, or at the times of their passing the
zenith or nadir; but as it is probable, that the stimulus of the particles
of the circumfluent blood is gradually diminished from the time of the
quadratures to that of the syzygies, the quiescence may commence at any
hour, when co-operating with other causes of quiescence, it becomes great
enough to produce a disease: afterwards it will continue to recur at the
same period of the lunar or solar influence; the same cause operating
conjointly with the acquired habit, that is with the catenation of this new
motion with the dissevered links of the lunar or solar circles of animal
action.
In this manner the periods of menstruation obey the lunar month with great
exactness in healthy patients (and perhaps the venereal orgasm in brute
animals does the same), yet these periods do not commence either at the
syzygies or quadratures of the lunations, but at whatever time of the lunar
periods they begin, they observe the same in their returns till some
greater cause disturbs them.
Hence, though the best way to calculate the time of the expected returns of
the paroxysms of periodical diseases is to count the number of hours
between the commencement of the two preceding fits, yet the following
observations may be worth attending to, when we endeavour to prevent the
returns of maniacal or epileptic diseases; whose periods (at the beginning
of them especially) frequently observe the syzygies of the moon and sun,
and particularly about the equinox.
The greatest of the two tides happening in every revolution of the moon, is
that when the moon approaches nearest to the zenith or nadir; for this
reason, while the sun is in the northern signs, that is during the vernal
and summer months, the greater of the two diurnal tides in our latitude is
that, when the moon is above the horizon; and when the sun is in the
southern signs, or during the autumnal and winter months, the greater tide
is that, which arises when the moon is below the horizon: and as the sun
approaches somewhat nearer the earth in winter than in summer, the greatest
equinoctial tides are observed to be a little before the vernal equinox,
and a little after the autumnal one.
Do not the cold periods of lunar diseases commence a few hours before the
southing of the moon during the vernal and summer months, and before the
northing of the moon during the autumnal and winter months? Do not palsies
and apoplexies, which occur about the equinoxes, happen a few days before
the vernal equinoctial lunation, and after the autumnal one? Are not the
periods of those diurnal diseases more obstinate, that commence many hours
before the southing or northing of the moon, than of those which commence
at those times? Are not those palsies and apoplexies more dangerous which
commence many days before the syzygies of the moon, than those which happen
at those times? See Sect. XXXVI. on the periods of diseases.
VII. Another very frequent cause of the cold fit of fever is the quiescence
of some of those large congeries of glands, which compose the liver,
spleen, or pancreas; one or more of which are frequently so enlarged in the
autumnal intermittents as to be perceptible to the touch externally, and
are called by the vulgar ague-cakes. As these glands are stimulated into
action by the specific pungency of the fluids, which they absorb, the
general cause of their quiescence seems to be the too great insipidity of
the fluids of the body, co-operating perhaps at the same time with other
general causes of quiescence.
Hence, in marshy countries at cold seasons, which have succeeded hot ones,
and amongst those, who have lived on innutritious and unstimulating diet,
these agues are most frequent. The enlargement of these quiescent viscera,
and the swelling of the præcordia in many other fevers, is, most probably,
owing to the same cause; which may consist in a general deficiency of the
production of sensorial power, as well as in the diminished stimulation of
the fluids; and when the quiescence of so great a number of glands, as
constitute one of those large viscera, commences, all the other irritative
motions are affected by their connection with it, and the cold fit of fever
is produced.
VIII. There are many other causes, which produce quiescence of some part of
the animal system, as fatigue, hunger, thirst, bad diet, disappointed love,
unwholesome air, exhaustion from evacuations, and many others; but the last
cause, that we shall mention, as frequently productive of cold fits of
fever, is fear or anxiety of mind. The pains, which we are first and most
generally acquainted with, have been produced by defect of some stimulus;
thus, soon after our nativity we become acquainted with the pain from the
coldness of the air, from the want of respiration, and from the want of
food. Now all these pains occasioned by defect of stimulus are attended
with quiescence of the organ, and at the same time with a greater or less
degree of quiescence of other parts of the system: thus, if we even endure
the pain of hunger so as to miss one meal instead of our daily habit of
repletion, not only the peristaltic motions of the stomach and bowels are
diminished, but we are more liable to coldness of our extremities, as of
our noses, and ears, and feet, than at other times.
Now, as fear is originally excited by our having experienced pain, and is
itself a painful affection, the same quiescence of other fibrous motions
accompany it, as have been most frequently connected with this kind of
pain, as explained in Sect. XVI. 8. 1. as the coldness and paleness of the
skin, trembling, difficult respiration, indigestion, and other symptoms,
which contribute to form the cold fit of fevers. Anxiety is fear continued
through a longer time, and, by producing chronical torpor of the system,
extinguishes life slowly, by what is commonly termed a broken heart.
IX. 1. We now step forwards to consider the other symptoms in consequence
of the quiescence which begins the fits of fever. If by any of the
circumstances before described, or by two or more of them acting at the
same time, a great degree of quiescence is induced on any considerable part
of the circle of irritative motions, the whole class of them is more or
less disturbed by their irritative associations. If this torpor be
occasioned by a deficient supply of sensorial power, and happens to any of
those parts of the system, which are accustomed to perpetual activity, as
the vital motions, the torpor increases rapidly, because of the great
expenditure of sensorial power by the incessant activity of those parts of
the system, as shewn in No. 3. 2. of this Section. Hence a deficiency of
all the secretions succeeds, and as animal heat is produced in proportion
to the quantity of those secretions, the coldness of the skin is the first
circumstance, which is attended to. Dr. Martin asserts, that some parts of
his body were warmer than natural in the cold fit of fever; but it is
certain, that those, which are uncovered, as the fingers, and nose, and
ears, are much colder to the touch, and paler in appearance. It is
possible, that his experiments were made at the beginning of the subsequent
hot fits; which commence with partial distributions of heat, owing to some
parts of the body regaining their natural irritability sooner than others.
From the quiescence of the anastomosing capillaries a paleness of the skin
succeeds, and a less secretion of the perspirable matter; from the
quiescence of the pulmonary capillaries a difficulty of respiration arises;
and from the quiescence of the other glands less bile, less gastric and
pancreatic juice, are secreted into the stomach and intestines, and less
mucus and saliva are poured into the mouth; whence arises the dry tongue,
costiveness, dry ulcers, and paucity of urine. From the quiescence of the
absorbent system arises the great thirst, as less moisture is absorbed from
the atmosphere. The absorption from the atmosphere was observed by Dr.
Lyster to amount to eighteen ounces in one night, above what he had at the
same time insensibly perspired. See Langrish. On the same account the urine
is pale, though in small quantity, for the thinner part is not absorbed
from it; and when repeated ague-fits continue long, the legs swell from the
diminished absorption of the cellular absorbents.
From the quiescence of the intestinal canal a loss of appetite and
flatulencies proceed. From the partial quiescence of the glandular viscera
a swelling and tension about the præcordia becomes sensible to the touch;
which is occasioned by the delay of the fluids from the defect of venous or
lymphatic absorption. The pain of the forehead, and of the limbs, and of
the small of the back, arises from the quiescence of the membranous fascia,
or muscles of those parts, in the same manner as the skin becomes painful,
when the vessels, of which it is composed, become quiescent from cold. The
trembling in consequence of the pain of coldness, the restlessness, and the
yawning, and stretching of the limbs, together with the shuddering, or
rigours, are convulsive motions; and will be explained amongst the diseases
of volition; Sect. XXXIV.
Sickness and vomiting is a frequent symptom in the beginnings of
fever-fits, the muscular fibres of the stomach share the general torpor and
debility of the system; their motions become first lessened, and then stop,
and then become retrograde; for the act of vomiting, like the globus
hystericus and the borborigmi of hypochondriasis, is always a symptom of
debility, either from want of stimulus, as in hunger; or from want of
sensorial power, as after intoxication; or from sympathy with some other
torpid irritative motions, as in the cold fits of ague. See Sect. XII. 5.
5. XXIX. 11. and XXXV. 1. 3. where this act of vomiting is further
explained.
The small pulse, which is said by some writers to be slow at the
commencement of ague-fits, and which is frequently trembling and
intermittent, is owing to the quiescence of the heart and arterial system,
and to the resistance opposed to the circulating fluid from the inactivity
of all the glands and capillaries. The great weakness and inability to
voluntary motions, with the insensibility of the extremities, are owing to
the general quiescence of the whole moving system; or, perhaps, simply to
the deficient production of sensorial power.
If all these symptoms are further increased, the quiescence of all the
muscles, including the heart and arteries, becomes complete, and death
ensues. This is, most probably, the case of those who are starved to death
with cold, and of those who are said to die in Holland from long skaiting
on their frozen canals.
2. As soon as this general quiescence of the system ceases, either by the
diminution of the cause, or by the accumulation of sensorial power, (as in
syncope, Sect. XII. 7. 1.) which is the natural consequence of previous
quiescence, the hot fit commences. Every gland of the body is now
stimulated into stronger action than is natural, as its irritability is
increased by accumulation of sensorial power during its late quiescence, a
superabundance of all the secretions is produced, and an increase of heat
in consequence of the increase of these secretions. The skin becomes red,
and the perspiration great, owing to the increased action of the
capillaries during the hot part of the paroxysm. The secretion of
perspirable matter is perhaps greater during the hot fit than in the
sweating fit which follows; but as the absorption of it also is greater, it
does not stand on the skin in visible drops: add to this, that the
evaporation of it also is greater, from the increased heat of the skin. But
at the decline of the hot fit, as the mouths of the absorbents of the skin
are exposed to the cooler air, or bed-clothes, these vessels sooner lose
their increased activity, and cease to absorb more than their natural
quantity: but the secerning vessels for some time longer, being kept warm
by the circulating blood, continue to pour out an increased quantity of
perspirable matter, which now stands on the skin in large visible drops;
the exhalation of it also being lessened by the greater coolness of the
skin, as well as its absorption by the diminished action of the lymphatics.
See Class I. 1. 2. 3.
The increased secretion of bile and of other fluids poured into the
intestines frequently induce a purging at the decline of the hot fit; for
as the external absorbent vessels have their mouths exposed to the cold
air, as above mentioned, they cease to be excited into unnatural activity
sooner than the secretory vessels, whose mouths are exposed to the warmth
of the blood: now, as the internal absorbents sympathize with the external
ones, these also, which during the hot fit drank up the thinner part of the
bile, or of other secreted fluids, lose their increased activity before the
gland loses its increased activity, at the decline of the hot fit; and the
loose dejections are produced from the same cause, that the increased
perspiration stands on the surface of the skin, from the increased
absorption ceasing sooner than the increased secretion.
The urine during the cold fit is in small quantity and pale, both from a
deficiency of the secretion and a deficiency of the absorption.
During the hot fit it is in its usual quantity, but very high coloured and
turbid, because a greater quantity had been secreted by the increased
action of the kidnies, and also a greater quantity of its more aqueous part
had been absorbed from it in the bladder by the increased action of the
absorbents; and lastly, at the decline of the hot fit it is in large
quantity and less coloured, or turbid, because the absorbent vessels of the
bladder, as observed above, lose their increased action by sympathy with
the cutaneous ones sooner than the secretory vessels of the kidnies lose
their increased activity. Hence the quantity of the sediment, and the
colour of the urine, in fevers, depend much on the quantity secreted by the
kidnies, and the quantity absorbed from it again in the bladder: the kinds
of sediment, as the lateritious, purulent, mucous, or bloody sediments,
depend on other causes. It should be observed, that if the sweating be
increased by the heat of the room, or of the bed-clothes, that a paucity of
turbid urine will continue to be produced, as the absorbents of the bladder
will have their activity increased by their sympathy with the vessels of
the skin, for the purpose of supplying the fluid expended in perspiration.
The pulse becomes strong and full owing to the increased irritability of
the heart and arteries, from the accumulation of sensorial power during
their quiescence, and to the quickness of the return of the blood from the
various glands and capillaries. This increased action of all the secretory
vessels does not occur very suddenly, nor universally at the same time. The
heat seems to begin about the center, and to be diffused from thence
irregularly to the other parts of the system. This may be owing to the
situation of the parts which first became quiescent and caused the
fever-fit, especially when a hardness or tumour about the præcordia can be
felt by the hand; and hence this part, in whatever viscus it is seated,
might be the first to regain its natural or increased irritability.
3. It must be here noted, that, by the increased quantity of heat, and of
the impulse of the blood at the commencement of the hot fit, a great
increase of stimulus is induced, and is now added to the increased
irritability of the system, which was occasioned by its previous
quiescence. This additional stimulus of heat and momentum of the blood
augments the violence of the movements of the arterial and glandular system
in an increasing ratio. These violent exertions still producing more heat
and greater momentum of the moving fluids, till at length the sensoral
power becomes wasted by this great stimulus beneath its natural quantity,
and predisposes the system to a second cold fit.
At length all these unnatural exertions spontaneously subside with the
increased irritability that produced them; and which was itself produced by
the preceding quiescence, in the same manner as the eye, on coming from
darkness into day-light, in a little time ceases to be dazzled and pained,
and gradually recovers its natural degree of irritability.
4. But if the increase of irritability, and the consequent increase of the
stimulus of heat and momentum, produce more violent exertions than those
above described; great pain arises in some part of the moving system, as in
the membranes of the brain, pleura, or joints; and new motions of the
vessels are produced in consequence of this pain, which are called
inflammation; or delirium or stupor arises; as explained in Sect. XXI. and
XXXIII.: for the immediate effect is the same, whether the great energy of
the moving organs arises from an increase of stimulus or an increase of
irritability; though in the former case the waste of sensorial power leads
to debility, and in the latter to health.
_Recapitulation._
X. Those muscles, which are less frequently exerted, and whose actions are
interrupted by sleep, acquire less accumulation of sensorial power during
their quiescent state, as the muscles of locomotion. In these muscles after
great exertion, that is, after great exhaustion of sensorial power, the
pain of fatigue ensues; and during rest there is a renovation of the
natural quantity of sensorial power; but where the rest, or quiescence of
the muscle, is long continued, a quantity of sensorial power becomes
accumulated beyond what is necessary; as appears by the uneasiness
occasioned by want of exercise; and which in young animals is one cause
exciting them into action, as is seen in the play of puppies and kittens.
But when those muscles, which are habituated to perpetual actions, as those
of the stomach by the stimulus of food, those of the vessels of the skin by
the stimulus of heat, and those which constitute the arteries and glands by
the stimulus of the blood, become for a time quiescent, from the want of
their appropriated stimuli, or by their associations with other quiescent
parts of the system; a greater accumulation of sensorial power is acquired
during their quiescence, and a greater or quicker exhaustion of it is
produced during their increased action.
This accumulation of sensorial power from deficient action, if it happens
to the stomach from want of food, occasions the pain of hunger; if it
happens to the vessels of the skin from want of heat, it occasions the pain
of cold; and if to the arterial system from the want of its adapted
stimuli, many disagreeable sensations are occasioned, such as are
experienced in the cold fits of intermittent fevers, and are as various, as
there are glands or membranes in the system, and are generally termed
universal uneasiness.
When the quiescence of the arterial system is not owing to defect of
stimulus as above, but to the defective quantity of sensorial power, as in
the commencement of nervous fever, or irritative fever with weak pulse, a
great torpor of this system is quickly induced; because both the irritation
from the stimulus of the blood, and the association of the vascular motions
with each other, continue to excite the arteries into action, and thence
quickly exhaust the ill-supplied vascular muscles; for to rest is death;
and therefore those vascular muscles continue to proceed, though with
feebler action, to the extreme of weariness or faintness: while nothing
similar to this affects the locomotive muscles, whose actions are generally
caused by volition, and not much subject either to irritation or to other
kinds of associations besides the voluntary ones, except indeed when they
are excited by the lash of slavery.
In these vascular muscles, which are subject to perpetual action, and
thence liable to great accumulation of sensorial power during their
quiescence from want of stimulus, a great increase of activity occurs,
either from the renewal of their accustomed stimulus, or even from much
less quantities of stimulus than usual. This increase of action constitutes
the hot fit of fever, which is attended with various increased secretions,
with great concomitant heat, and general uneasiness. The uneasiness
attending this hot paroxysm of fever, or fit of exertion, is very different
from that, which attends the previous cold fit, or fit of quiescence, and
is frequently the cause of inflammation, as in pleurisy, which is treated
of in the next section.
A similar effect occurs after the quiescence of our organs of sense; those
which are not subject to perpetual action, as the taste and smell, are less
liable to an exuberant accumulation of sensorial power after their having
for a time been inactive; but the eye, which is in perpetual action during
the day, becomes dazzled, and liable to inflammation after a temporary
quiescence.
Where the previous quiescence has been owing to a defect of sensorial
power, and not to a defect of stimulus, as in the irritative fever with
weak pulse, a similar increase of activity of the arterial system succeeds,
either from the usual stimulus of the blood, or from a stimulus less than
usual; but as there is in general in these cases of fever with weak pulse a
deficiency of the quantity of the blood, the pulse in the hot fit is weaker
than in health, though it is stronger than in the cold fit, as explained in
No. 2. of this section. But at the same time in those fevers, where the
defect of irritation is owing to the defect of the quantity of sensorial
power, as well as to the defect of stimulus, another circumstance occurs;
which consists in the partial distribution of it, as appears in partial
flushings, as of the face or bosom, while the extremities are cold; and in
the increase of particular secretions, as of bile, saliva, insensible
perspiration, with great heat of the skin, or with partial sweats, or
diarrhoea.
There are also many uneasy sensations attending these increased actions,
which, like those belonging to the hot fit of fever with strong pulse, are
frequently followed by inflammation, as in scarlet fever; which
inflammation is nevertheless accompanied with a pulse weaker, though
quicker, than the pulse during the remission or intermission of the
paroxysms, though stronger than that of the previous cold fit.
From hence I conclude, that both the cold and hot fits of fever are
necessary consequences of the perpetual and incessant action of the
arterial and glandular system; since those muscular fibres and those organs
of sense, which are most frequently exerted, become necessarily most
affected both with defect and accumulation of sensorial power: and that
hence _fever-fits are not an effort of nature to relieve herself_, and that
therefore they should always be prevented or diminished as much as
possible, by any means which decrease the general or partial vascular
actions, when they are greater, or by increasing them when they are less
than in health, as described in Sect. XII. 6. 1.
Thus have I endeavoured to explain, and I hope to the satisfaction of the
candid and patient reader, the principal symptoms or circumstances of fever
without the introduction of the supernatural power of spasm. To the
arguments in favour of the doctrine of spasm it may be sufficient to reply,
that in the evolution of medical as well as of dramatic catastrophe,
Nec Deus intersit, nisi dignus vindice nodus inciderit.--HOR.
* * * * *
SECT. XXXIII.
DISEASES OF SENSATION.
I. 1. _Motions excited by sensation. Digestion. Generation. Pleasure of
existence. Hypochondriacism._ 2. _Pain introduced. Sensitive fevers of
two kinds._ 3. _Two sensorial powers exerted in sensitive fevers. Size
of the blood. Nervous fevers distinguished from putrid ones. The septic
and antiseptic theory._ 4. _Two kinds of delirium._ 5. _Other animals
are less liable to delirium, cannot receive our contagious diseases,
and are less liable to madness._ II. 1. _Sensitive motions generated._
2. _Inflammation explained._ 3. _Its remote causes from excess of
irritation, or of irritability, not from those pains which are owing to
defect of irritation. New vessels produced, and much heat._ 4.
_Purulent matter secreted._ 5. _Contagion explained._ 6. _Received but
once._ 7. _If common matter be contagious?_ 8. _Why some contagions are
received but once._ 9. _Why others may be received frequently.
Contagions of small-pox and measles do not act at the same times. Two
cases of such patients._ 10. _The blood from patients in the small-pox
will not infect others. Cases of children thus inoculated. The
variolous contagion is not received into the blood. It acts by
sensitive association between the stomach and skin._ III. 1.
_Absorption of solids and fluids._ 2. _Art of healing ulcers._ 3.
_Mortification attended with less pain in weak people._
I. 1. As many motions of the body are excited and continued by irritations,
so others require, either conjunctly with these, or separately, the
pleasurable or painful sensations, for the purpose of producing them with
due energy. Amongst these the business of digestion supplies us with an
instance: if the food, which we swallow, is not attended with agreeable
sensation, it digests less perfectly; and if very disagreeable sensation
accompanies it, such as a nauseous idea, or very disgustful taste, the
digestion becomes impeded; or retrograde motions of the stomach and
oesophagus succeed, and the food is ejected.
The business of generation depends so much on agreeable sensation, that,
where the object is disgustful, neither voluntary exertion nor irritation
can effect the purpose; which is also liable to be interrupted by the pain
of fear or bashfulness.
Besides the pleasure, which attends the irritations produced by the objects
of lust and hunger, there seems to be a sum of pleasurable affection
accompanying the various secretions of the numerous glands, which
constitute the pleasure of life, in contradistinction to the tedium vitæ.
This quantity or sum of pleasurable affection, seems to contribute to the
due or energetic performance of the whole moveable system, as well that of
the heart and arteries, as of digestion and of absorption; since without
the due quantity of pleasurable sensation, flatulency and hypochondriacism
affect the intestines, and a languor seizes the arterial pulsations and
secretions; as occurs in great and continued anxiety of the mind.
2. Besides the febrile motions occasioned by irritation, described in Sect.
XXXII. and termed irritative fever, it frequently happens that pain is
excited by the violence of the fibrous contractions; and other new motions
are then superadded, in consequence of sensation, which we shall term
febris sensitiva, or sensitive fever. It must be observed, that most
irritative fevers begin with a decreased exertion of irritation, owing to
defect of stimulus; but that on the contrary the sensitive fevers, or
inflammations, generally begin with the increased exertion of sensation, as
mentioned in Sect. XXXI. on temperaments: for though the cold fit, which
introduces inflammation, commences with decreased irritation, yet the
inflammation itself commences in the hot fit during the increase of
sensation. Thus a common pustule, or phlegmon, in a part of little
sensibility does not excite an inflammatory fever; but if the stomach,
intestines, or the tender substance beneath the nails, be injured, great
sensation is produced, and the whole system is thrown into that kind of
exertion, which constitutes inflammation.
These sensitive fevers, like the irritative ones, resolve themselves into
those with arterial strength, and those with arterial debility, that is
with excess or defect of sensorial power; these may be termed the febris
sensitiva pulsu forti, sensitive fever with strong pulse, which is the
synocha, or inflammatory fever; and the febris sensitiva pulsu debili,
sensitive fever with weak pulse, which is the typhus gravior, or putrid
fever of some writers.
3. The inflammatory fevers, which are here termed sensitive fevers with
strong pulse, are generally attended with some topical inflammation, as
pleurisy, peripneumony, or rheumatism, which distinguishes them from
irritative fevers with strong pulse. The pulse is strong, quick, and full;
for in this fever there is great irritation, as well as great sensation,
employed in moving the arterial system. The size, or coagulable lymph,
which appears on the blood, is probably an increased secretion from the
inflamed internal lining of the whole arterial system, the thinner part
being taken away by the increased absorption of the inflamed lymphatics.
The sensitive fevers with weak pulse, which are termed putrid or malignant
fevers, are distinguished from irritative fevers with weak pulse, called
nervous fevers, described in the last section, as the former consist of
inflammation joined with debility, and the latter of debility alone. Hence
there is greater heat and more florid colour of the skin in the former,
with petechiæ, or purple spots, and aphthæ, or sloughs in the throat, and
generally with previous contagion.
When animal matter dies, as a slough in the throat, or the mortified part
of a carbuncle, if it be kept moist and warm, as during its abhesion to a
living body, it will soon putrify. This, and the origin of contagion from
putrid animal substances, seem to have given rise to the septic and
antiseptic theory of these fevers.
The matter in pustules and ulcers is thus liable to become putrid, and to
produce microscopic animalcula; the urine, if too long retained, may also
gain a putrescent smell, as well as the alvine feces; but some writers have
gone so far as to believe, that the blood itself in these fevers has smelt
putrid, when drawn from the arm of the patient: but this seems not well
founded; since a single particle of putrid matter taken into the blood can
produce fever, how can we conceive that the whole mass could continue a
minute in a putrid state without destroying life? Add to this, that putrid
animal substances give up air, as in gangrenes; and that hence if the blood
was putrid, air should be given out, which in the blood-vessels is known to
occasion immediate death.
In these sensitive fevers with strong pulse (or inflammations) there are
two sensorial faculties concerned in producing the disease, viz. irritation
and sensation; and hence, as their combined action is more violent, the
general quantity of sensorial power becomes further exhausted during the
exacerbation, and the system more rapidly weakened than in irritative fever
with strong pulse; where the spirit of animation is weakened by but one
mode of its exertion: so that this febris sensitiva pulsu forti (or
inflammatory fever,) may be considered as the febris irritativa pulsu
forti, with the addition of inflammation; and the febris sensitiva pulsu
debili (or malignant fever) may be considered as the febris irritativa
pulsu debili (or nervous fever), with the addition of inflammation.
4. In these putrid or malignant fevers a deficiency of irritability
accompanies the increase of sensibility; and by this waste of sensorial
power by the excess of sensation, which was already too small, arises the
delirium and stupor which so perpetually attend these inflammatory fevers
with arterial debility. In these cases the voluntary power first ceases to
act from deficiency of sensorial spirit; and the stimuli from external
bodies have no effect on the exhausted sensorial power, and a delirium like
a dream is the consequence. At length the internal stimuli cease to excite
sufficient irritation, and the secretions are either not produced at all,
or too parsimonious in quantity. Amongst these the secretion of the brain,
or production of the sensorial power, becomes deficient, till at last all
sensorial power ceases, except what is just necessary to perform the vital
motions, and a stupor succeeds; which is thus owing to the same cause as
the preceding delirium exerted in a greater degree.
This kind of delirium is owing to a suspension of volition, and to the
disobedience of the senses to external stimuli, and is always occasioned by
great debility, or paucity of sensorial power; it is therefore a bad sign
at the end of inflammatory fevers, which had previous arterial strength, as
rheumatism, or pleurisy, as it shews the presence of great exhaustion of
sensorial power in a system, which having lately been exposed to great
excitement, is not so liable to be stimulated into its healthy action,
either by additional stimulus of food and medicines, or by the accumulation
of sensorial power during its present torpor. In inflammatory fevers with
debility, as those termed putrid fevers, delirium is sometimes, as well as
stupor, rather a favourable sign; as less sensorial power is wasted during
its continuance (see Class II. 1. 6. 8.), and the constitution not having
been previously exposed to excess of stimulation, is more liable to be
excited after previous quiescence.
When the sum of general pleasurable sensation becomes too great, another
kind of delirium supervenes, and the ideas thus excited are mistaken for
the irritations of external objects: such a delirium is produced for a time
by intoxicating drugs, as fermented liquors, or opium: a permanent delirium
of this kind is sometimes induced by the pleasures of inordinate vanity, or
by the enthusiastic hopes of heaven. In these cases the power of volition
is incapable of exertion, and in a great degree the external senses become
incapable of perceiving their adapted stimuli, because the whole sensorial
power is employed or expended on the ideas excited by pleasurable
sensation.
This kind of delirium is distinguished from that which attends the fevers
above mentioned from its not being accompanied with general debility, but
simply with excess of pleasurable sensation; and is therefore in some
measure allied to madness or to reverie; it differs from the delirium of
dreams, as in this the power of volition is not totally suspended, nor are
the senses precluded from external stimulation; there is therefore a degree
of consistency, in this kind of delirium, and a degree of attention to
external objects, neither of which exist in the delirium of fevers or in
dreams.
5. It would appear, that the vascular system of other animals are less
liable to be put into action by their general sum of pleasurable or painful
sensation; and that the trains of their ideas, and the muscular motions
usually associated with them, are less powerfully connected than in the
human system. For other animals neither weep, nor smile, nor laugh; and are
hence seldom subject to delirium, as treated of in Sect. XVI. on Instinct.
Now as our epidemic and contagious diseases are probably produced by
disagreeable sensation, and not simply by irritation; there appears a
reason, why brute animals are less liable to epidemic or contagious
diseases; and secondly, why none of our contagions, as the small-pox or
measles, can be communicated to them, though one of theirs, viz. the
hydrophobia, as well as many of their poisons, as those of snakes and of in
insects, communicate their deleterious or painful effects to mankind.
Where the quantity of general painful sensation is too great in the system,
inordinate voluntary exertions are produced either of our ideas, as in
melancholy and madness, or of our muscles, as in convulsion. From these
maladies also brute animals are much more exempt than mankind, owing to
their greater inaptitude to voluntary exertion, as mentioned in Sect. XVI.
on Instinct.
II. 1. When any moving organ is excited into such violent motions, that a
quantity of pleasurable or painful sensation is produced, it frequently
happens (but not always) that new motions of the affected organ are
generated in consequence of the pain or pleasure, which are termed
inflammation.
These new motions are of a peculiar kind, tending to distend the old, and
to produce new fibres, and thence to elongate the straight muscles, which
serve locomotion, and to form new vessels at the extremities or sides of
the vascular muscles.
2. Thus the pleasurable sensations produce an enlargement of the nipples of
nurses, of the papillæ of the tongue, of the penis, and probably produce
the growth of the body from its embryon state to its maturity; whilst the
new motions in consequence of painful sensation, with the growth of the
fibres or vessels, which they occasion, are termed inflammation.
Hence when the straight muscles are inflamed, part of their tendons at each
extremity gain new life and sensibility, and thus the muscle is for a time
elongated; and inflamed bones become soft, vascular, and sensible. Thus new
vessels shoot over the cornea of inflamed eyes, and into scirrhous tumours,
when they become inflamed; and hence all inflamed parts grow together by
intermixture, and inosculation of the new and old vessels.
The heat is occasioned from the increased secretions either of mucus, or of
the fibres, which produce or elongate the vessels. The red colour is owing
to the pellucidity of the newly formed vessels, and as the arterial parts
of them are probably formed before their correspondent venous parts.
3. These new motions are excited either from the increased quantity of
sensation in consequence of greater fibrous contractions, or from increased
sensibility, that is, from the increased quantity of sensorial power in the
moving organ. Hence they are induced by great external stimuli, as by
wounds, broken bones; and by acrid or infectious materials; or by common
stimuli on those organs, which have been some time quiescent; as the usual
light of the day inflames the eyes of those, who have been confined in
dungeons; and the warmth of a common fire inflames those, who have been
previously exposed to much cold.
But these new motions are never generated by that pain, which arises from
defect of stimulus, as from hunger, thirst, cold, or inanition, with all
those pains, which are termed nervous. Where these pains exist, the motions
of the affected part are lessened; and if inflammation succeeds, it is in
some distant parts; as coughs are caused by coldness and moisture being
long applied to the feet; or it is in consequence of the renewal of the
stimulus, as of heat or food, which excites our organs into stronger action
after their temporary quiescence; as kibed heels after walking in snow.
4. But when these new motions of the vascular muscles are exerted with
greater violence, and these vessels are either elongated too much or too
hastily, a new material is secreted from their extremities, which is of
various kinds according to the peculiar animal motions of this new kind of
gland, which secretes it; such is the pus laudabile or common matter, the
variolous matter, venereal matter, catarrhous matter, and many others.
5. These matters are the product of an animal process; they are secreted or
produced from the blood by certain diseased motions of the extremities of
the blood-vessels, and are on that account all of them contagious; for if a
portion of any of these matters is transmitted into the circulation, or
perhaps only inserted into the skin, or beneath the cuticle of an healthy
person, its stimulus in a certain time produces the same kind of morbid
motions, by which itself was produced; and hence a similar kind is
generated. See Sect. XXXIX. 6. 1.
6. It is remarkable, that many of these contagious matters are capable of
producing a similar disease but once; as the small-pox and measles; and I
suppose this is true of all those contagious diseases, which are
spontaneously cured by nature in a certain time; for if the body was
capable of receiving the disease a second time, the patient must
perpetually infect himself by the very matter, which he has himself
produced, and is lodged about him; and hence he could never become free
from the disease. Something similar to this is seen in the secondary fever
of the confluent small-pox; there is a great absorption of variolous
matter, a very minute part of which would give the genuine small-pox to
another person; but here it only stimulates the system into common fever;
like that which common puss, or any other acrid material might occasion.
7. In the pulmonary consumption, where common matter is daily absorbed, an
irritative fever only, without new inflammation, is generally produced;
which is terminated like other irritative fevers by sweats, or loose
stools. Hence it does not appear, that this absorbed matter always acts as
a contagious material producing fresh inflammation or new abscesses. Though
there is reason to believe, that the first time any common matter is
absorbed, it has this effect, but not the second time, like the variolous
matter above mentioned.
This accounts for the opinion, that the pulmonary consumption is sometimes
infectious, which opinion was held by the ancients, and continues in Italy
at present; and I have myself seen three or four instances, where a husband
and wife, who have slept together, and have thus much received each other's
breath, who have infected each other, and both died in consequence of the
original taint of only one of them. This also accounts for the abscesses in
various parts of the body, that are sometimes produced after the inoculated
small-pox is terminated; for this second absorption of variolous matter
acts like common matter, and produces only irritative fever in those
children, whose constitutions have already experienced the absorption of
common matter; and inflammation with a tendency to produce new abscesses in
those, whose constitutions have not experienced the absorptions of common
matter.
It is probable, that more certain proofs might have been found to shew,
that common matter is infectious the first time it is absorbed, tending to
produce similar abscesses, but not the second time of its absorption, if
this subject had been attended to.
8. These contagious diseases are very numerous, as the plague, small-pox,
chicken-pox, measles, scarlet-fever, pemphigus, catarrh, chincough,
venereal disease, itch, trichoma, tinea. The infectious material does not
seem to be dissolved by the air, but only mixed with it perhaps in fine
powder, which soon subsides; since many of these contagions can only be
received by actual contact; and others of them only at small distances from
the infected person; as is evident from many persons having been near
patients of the small-pox without acquiring the disease.
The reason, why many of these diseases are received but once, and others
repeatedly, is not well understood; it appears to me, that the constitution
becomes so accustomed to the stimuli of these infectious materials, by
having once experienced them, that though irritative motions, as hectic
fevers, may again be produced by them, yet no sensation, and in consequence
no general inflammation succeeds; as disagreeable smells or tastes by habit
cease to be perceived; they continue indeed to excite irritative ideas on
the organs of sense, but these are not succeeded by sensation.
There are many irritative motions, which were at first succeeded by
sensation, but which by frequent repetition cease to excite sensation, as
explained in Sect. XX. on Vertigo. And, that this circumstance exists in
respect to infectious matter appears from a known fact; that nurses, who
have had the small-pox, are liable to experience small ulcers on their arms
by the contact of variolous matter in lifting their patients; and that when
patients, who have formerly had the small-pox have been inoculated in the
arm, a phlegmon, or inflamed sore, has succeeded, but no subsequent fever.
Which shews, that the contagious matter of the small-pox has not lost its
power of stimulating the part it is applied to, but that the general system
is not affected in consequence. See Section XII. 7. 6. XIX. 9.
9. From the accounts of the plague, virulent catarrh, and putrid dysentery,
it seems uncertain, whether these diseases are experienced more than once;
but the venereal disease and itch are doubtless repeatedly infectious; and
as these diseases are never cured spontaneously, but require medicines,
which act without apparent operation, some have suspected, that the
contagious material produces similar matter rather by a chemical change of
the fluids, than by an animal process; and that the specific medicines
destroy their virus by chemically combining with it. This opinion is
successfully combated by Mr. Hunter, in his Treatise on Venereal Disease,
Part I. c. i.
But this opinion wants the support of analogy, as there is no known process
in animal bodies, which is purely chemical, not even digestion; nor can any
of these matters be produced by chemical processes. Add to this, that it is
probable, that the insects, observed in the pustules of the itch, and in
the stools of dysenteric patients, are the consequences, and not the causes
of these diseases. And that the specific medicines, which cure the itch and
lues venerea, as brimstone and mercury, act only by increasing the
absorption of the matter in the ulcuscles of those diseases, and thence
disposing them to heal; which would otherwise continue to spread.
Why the venereal disease, and itch, and tenia, or scald head, are
repeatedly contagious, while those contagions attended with fever can be
received but once, seems to depend on their being rather local diseases
than universal ones, and are hence not attended with fever, except the
purulent fever in their last stages, when the patient is destroyed by them.
On this account the whole of the system does not become habituated to these
morbid actions, so as to cease to be affected with sensation by a
repetition of the contagion. Thus the contagious matter of the venereal
disease, and of the tenia, affects the lymphatic glands, as the inquinal
glands, and those about the roots of the hair and neck, where it is
arrested, but does not seem to affect the blood-vessels, since no fever
ensues.
Hence it would appear, that these kinds of contagion are propagated not by
means of the circulation, but by sympathy of distant parts with each other;
since if a distant part, as the palate, should be excited by sensitive
association into the same kind of motions, as the parts originally affected
by the contact of infectious matter; that distant part will produce the
same kind of infectious matter; for every secretion from the blood is
formed from it by the peculiar motions of the fine extremities of the
gland, which secretes it; the various secreted fluids, as the bile, saliva,
gastric juice, not previously existing, as such, in the blood-vessels.
And this peculiar sympathy between the genitals and the throat, owing to
sensitive association, appears not only in the production of venereal
ulcers in the throat, but in variety of other instances, as in the mumps,
in the hydrophobia, some coughs, strangulation, the production of the
beard, change of voice at puberty. Which are further described in Class IV.
1. 2. 7.
To evince that the production of such large quantities of contagious
matter, as are seen in some variolous patients, so as to cover the whole
skin almost with pustules, does not arise from any chemical fermentation in
the blood, but that it is owing to morbid motions of the fine extremities
of the capillaries, or glands, whether these be ruptured or not, appears
from the quantity of this matter always corresponding with the quantity of
the fever; that is, with the violent exertions of those glands and
capillaries, which are the terminations of the arterial system.
The truth of this theory is evinced further by a circumstance observed by
Mr. J. Hunter, in his Treatise on Venereal Disease; that in a patient, who
was inoculated for the small-pox, and who appeared afterwards to have been
previously infested with the measles, the progress of the small-pox was
delayed till the measles had run their course, and that then the small-pox
went through its usual periods.
Two similar cases fell under my care, which I shall here relate, as it
confirms that of Mr. Hunter, and contributes to illustrate this part of the
theory of contagious diseases. I have transcribed the particulars from a
letter of Mr. Lightwood of Yoxal, the surgeon who daily attended them, and
at my request, after I had seen them, kept a kind of journal of their
cases.
Miss H. and Miss L. two sisters, the one about four and the other about
three years old, were inoculated Feb. 7, 1791. On the 10th there was a
redness on both arms discernible by a glass. On the 11th their arms were so
much inflamed as to leave no doubt of the infection having taken place. On
the 12th less appearance of inflammation on their arms. In the evening Miss
L. had an eruption, which resembled the measles. On the 12th the eruption
on Miss L. was very full on the face and breast, like the measles, with
considerable fever. It was now known, that the measles were in a farm house
in the neighbourhood. Miss H.'s arm less inflamed than yesterday. On the
14th Miss L.'s fever great, and the eruption universal. The arm appears to
be healed. Miss H.'s arm somewhat redder. They were now put into separate
rooms. On the 15th Miss L.'s arms as yesterday. Eruption continues. Miss
H.'s arms have varied but little. 16th, the eruptions on Miss L. are dying
away, her fever gone. Begins to have a little redness in one arm at the
place of inoculation. Miss H.'s arms get redder, but she has no appearance
of complaint. 20th, Miss L.'s arms have advanced slowly till this day, and
now a few pustules appear. Miss H.'s arm has made little progress from the
16th to this day, and now she has some fever. 21st, Miss L. as yesterday.
Miss H. has much inflammation, and an increase of the red circle on one arm
to the size of half a crown, and had much fever at night, with fetid
breath. 22d, Miss L.'s pustules continue advancing. Miss H.'s inflammation
of her arm and red circle increases. A few red spots appear in different
parts with some degree of fever this morning, 23d. Miss L. has a larger
crop of pustules. Miss H. has small pustules and great inflammation of her
arms, with but one pustule likely to suppurate. After this day they
gradually got well, and the pustules disappeared.
In one of these cases the measles went through their common course with
milder symptoms than usual, and in the other the measly contagion seemed
just sufficient to stop the progress of variolous contagion, but without
itself throwing the constitution into any disorder. At the same time both
the measles and small-pox seem to have been rendered milder. Does not this
give an idea, that if they were both inoculated at the same time, that
neither of them might affect the patient?
From these cases I contend, that the contagious matter of these diseases
does not affect the constitution by a fermentation, or chemical change of
the blood, because then they must have proceeded together, and have
produced a third something, not exactly similar to either of them: but that
they produce new motions of the cutaneous terminations of the
blood-vessels, which for a time proceed daily with increasing activity,
like some paroxysms of fever, till they at length secrete or form a similar
poison by these unnatural actions.
Now as in the measles one kind of unnatural motion takes place, and in the
small-pox another kind, it is easy to conceive, that these different kinds
of morbid motions cannot exist together; and therefore, that that which has
first begun will continue till the system becomes habituated to the
stimulus which occasions it, and has ceased to be thrown into action by it;
and then the other kind of stimulus will in its turn produce fever, and new
kinds of motions peculiar to itself.
10. On further considering the action of contagious matter, since the
former part of this work was sent to the press; where I have asserted, in
Sect. XXII. 3. 3. that it is probable, that the variolous matter is
diffused through the blood; I prevailed on my friend Mr. Power, surgeon at
Bosworth in Leicestershire to try, whether the small-pox could be
inoculated by using the blood of a variolous patient instead of the matter
from the pustules; as I thought such an experiment might throw some light
at least on this interesting subject. The following is an extract from his
letter:--
"March 11, 1793. I inoculated two children, who had not had the small-pox,
with blood; which was taken from a patient on the second day after the
eruption commenced, and before it was completed. And at the same time I
inoculated myself with blood from the same person, in order to compare the
appearances, which might arise in a person liable to receive the infection,
and in one not liable to receive it. On the same day I inoculated four
other children liable to receive the infection with blood taken from
another person on the fourth day after the commencement of the eruption.
The patients from whom the blood was taken had the disease mildly, but had
the most pustules of any I could select from twenty inoculated patients;
and as much of the blood was insinuated under the cuticle as I could
introduce by elevating the skin without drawing blood; and three or four
such punctures were made in each of their arms, and the blood was used in
its fluid state.
"As the appearances in all these patients, as well as in myself, were
similar, I shall only mention them in general terms. March 13. A slight
subcuticular discoloration, with rather a livid appearance, without
soreness or pain, was visible in them all, as well as in my own hand. 15.
The discoloration somewhat less, without pain or soreness. Some patients
inoculated on the same day with variolous matter have considerable
inflammation. 17. The discoloration is quite gone in them all, and from my
own hand, a dry mark only remaining. And they were all inoculated on the
18th, with variolous matter, which produced the disease in them all."
Mr. Power afterwards observes, that, as the patients from whom the blood
was taken had the disease mildly, it may be supposed, that though the
contagious matter might be mixed with the blood, it might still be in too
dilute a state to convey the infection; but adds at the same time, that he
has diluted recent matter with at least five times its quantity of water,
and which has still given the infection; though he has sometimes diluted it
so far as to fail.
The following experiments were instituted at my request by my friend Mr.
Hadley, surgeon in Derby, to ascertain whether the blood of a person in the
small-pox be capable of communicating the disease. "Experiment 1st. October
18th, 1793. I took some blood from a vein in the arm of a person who had
the small-pox, on the second day of the eruption, and introduced a small
quantity of it immediately with the point of a lancet between the scars and
true skin of the right arm of a boy nine years old in two or three
different places; the other arm was inoculated with variolous matter at the
same time.
"19th. The punctured parts of the right arm were surrounded with some
degree of subcuticular inflammation. 20th. The inflammation more
considerable, with a slight degree of itching, but no pain upon pressure.
21st. Upon examining the arm this day with a lens I found the inflammation
less extensive, and the redness changing to a deep yellow or orange-colour,
22d. Inflammation nearly gone. 23d. Nothing remained, except a slight
discoloration and a little scurfy appearance on the punctures. At the same
time the inflammation of the arm inoculated with variolous matter was
increasing fast, and he had the disease mildly at the usual time.
"Experiment 2d. I inoculated another child at the same time and in the same
manner, with blood taken on the first day of the eruption; but as the
appearance and effects were similar to those in the preceding experiment, I
shall not relate them minutely.
"Experiment 3d. October 20th. Blood was taken from a person who had the
small-pox, on the third day of the eruption, and on the sixth from the
commencement of the eruptive fever. I introduced some of it in its fluid
state into both arms of a boy seven years old.
21st. There appeared to be some inflammation under the cuticle, where the
punctures were made. 22d. Inflammation more considerable. 23d. On this day
the inflammation was somewhat greater, and the cuticle rather elevated.
"24th. Inflammation much less, and only a brown or orange-colour remained.
25th. Scarcely any discoloration left. On this day he was inoculated with
variolous matter, the progress of the infection went on in the usual way,
and he had the small-pox very favourably.
"At this time I was requested to inoculate a young person, who was thought
to have had the small-pox, but his parents were not quite certain; in one
arm I introduced variolous matter, and in the other blood, taken as in
experiment 3d. On the second day after the operation, the punctured parts
were inflamed, though I think the arm in which I had inserted variolous
matter was rather more so than the other. On the third the inflammation was
increased, and looked much the same as in the preceding experiment. 4th.
The inflammation was much diminished, and on the 5th almost gone. He was
exposed at the same time to the natural infection, but has continued
perfectly well.
"I have frequently observed (and believe most practitioners have done the
same), that if variolous matter be inserted in the arm of a person who has
previously had the small-pox, that the inflammation on the second or third
days is much greater, than if they had not had the disease, but on the
fourth or fifth it disappears.
"On the 23d I introduced blood into the arms of three more children, taken
on the third and fourth days of the eruption. The appearances were much the
same as mentioned in experiments first and third. They were afterwards
inoculated with variolous matter, and had the disease in the regular way.
"The above experiments were made with blood taken from a small vein in the
hand or foot of three or four different patients, whom I had at that time
under inoculation. They were selected from 160, as having the greatest
number of pustules. The part was washed with warm water before the blood
was taken, to prevent the possibility of any matter being mixed with it
from the surface."
Shall we conclude from hence, that the variolous matter never enters the
blood-vessels? but that the morbid motions of the vessels of the skin
around the insertion of it continue to increase in a larger and larger
circle for six or seven days; that then their quantity of morbid action
becomes great enough to produce a fever-fit, and to affect the stomach by
association of motions? and finally, that a second association of motions
is produced between the stomach and the other parts of the skin, inducing
them into morbid actions similar to those of the circle round the insertion
of the variolous matter? Many more experiments and observations are
required before this important question can be satisfactorily answered.
It may be adduced, that as the matter inserted into the skin of the arm
frequently swells the lymphatic in the axilla, that in that circumstance it
seems to be there arrested in its progress, and cannot be imagined to enter
the blood by that lymphatic gland till the swelling of it subsides. Some
other phænomena of the disease are more easily reconcileable to this theory
of sympathetic motions than to that of absorption; as the time taken up
between the insertion of the matter, and the operation of it on the system,
as mentioned above. For the circle around the insertion is seen to
increase, and to inflame; and I believe, undergoes a kind of diurnal
paroxysm of torpor and paleness with a succeeding increase of action and
colour, like a topical fever-fit. Whereas if the matter is conceived to
circulate for six or seven days with the blood, without producing disorder,
it ought to be rendered milder, or the blood-vessels more familiarized to
its acrimony.
It is much easier to conceive from this doctrine of associated or
sympathetic motions of distant parts of the system, how it happens, that
the variolous infection can be received but once, as before explained; than
by supposing, that a change is effected in the mass of blood by any kind of
fermentative process.
The curious circumstance of the two contagions of small-pox and measles not
acting at the same time, but one of them resting or suspending its action
till that of the other ceases, may be much easier explained from
sympathetic or associated actions of the infected part with other parts of
the system, than it can from supposing the two contagions to enter the
circulation.
The skin of the face is subject to more frequent vicissitudes of heat and
cold, from its exposure to the open air, and is in consequence more liable
to sensitive association with the stomach than any other part of the
surface of the body, because their actions have been more frequently thus
associated. Thus in a surfeit from drinking cold water, when a person is
very hot and fatigued, an eruption is liable to appear on the face in
consequence of this sympathy. In the same manner the rosy eruption on the
faces of drunkards more probably arises from the sympathy of the face with
the stomach, rather than between the face and the liver, as is generally
supposed.
This sympathy between the stomach and the skin of the face is apparent in
the eruption of the small-pox; since, where the disease is in considerable
quantity, the eruption on the face first succeeds the sickness of the
stomach. In the natural disease the stomach seems to be frequently
primarily affected, either alone or along with the tonsils, as the matter
seems to be only diffused in the air, and by being mixed with the saliva,
or mucus of the tonsils, to be swallowed into the stomach.
After some days the irritative circles of motions become disordered by this
new stimulus, which acts upon the mucus lining of the stomach; and
sickness, vertigo, and a diurnal fever succeed. These disordered irritative
motions become daily increased for two or three days, and then by their
increased action certain sensitive motions, or inflammation, is produced,
and at the next cold fit of fever, when the stomach recovers from its
torpor, an inflammation of the external skin is formed in points (which
afterwards suppurate), by sensitive association, in the same manner as a
cough is produced in consequence of exposing the feet to cold, as described
in Sect. XXV. 17. and Class IV. 2. I. 7. If the inoculated skin of the arm,
as far as it appears inflamed, was to be cut out, or destroyed by caustic,
before the fever commenced, as suppose on the fourth day after inoculation,
would this prevent the disease? as it is supposed to prevent the
hydrophobia.
III. 1. Where the new vessels, and enlarged old ones, which constitute
inflammation, are not so hastily distended as to burst, and form a new kind
of gland for the secretion of matter, as above mentioned; if such
circumstances happen as diminish the painful sensation, the tendency to
growth ceases, and by and by an absorption commences, not only of the
superabundant quantity of fluids deposited in the inflamed part, but of the
solids likewise, and this even of the hardest kind.
Thus during the growth of the second set of teeth in children, the roots of
the first set are totally absorbed, till at length nothing of them remains
but the crown; though a few weeks before, if they are drawn immaturely,
their roots are found complete. Similar to this Mr. Hunter has observed,
that where a dead piece of bone is to exfoliate, or to separate from a
living one, that the dead part does not putrify, but remains perfectly
sound, while the surface of the living part of the bone, which is in
contact with the dead part, becomes absorbed, and thus effects its
separation. Med. Comment. Edinb. V. 1. 425. In the same manner the
calcareous matter of gouty concretions, the coagulable lymph deposited on
inflamed membranes in rheumatism and extravasated blood become absorbed;
which are all as solid and as indissoluble materials as the new vessels
produced in inflammation.
This absorption of the new vessels and deposited fluids of inflamed parts
is called resolution: it is produced by first using such internal means as
decrease the pain of the part, and in consequence its new motions, as
repeated bleeding, cathartics, diluent potations, and warm bath.
After the vessels are thus emptied, and the absorption of the new vessels
and deposited fluids is evidently begun, it is much promoted by stimulating
the part externally by solutions of lead, or other metals, and internally
by the bark, and small doses of opium. Hence when an ophthalmy begins to
become paler, any acrid eye-water, as a solution of six grains of white
vitriol in an ounce of water, hastens the absorption, and clears the eye in
a very short time. But the same application used a few days sooner would
have increased the inflammation. Hence after evacuation opium in small
doses may contribute to promote the absorption of fluids deposited on the
brain, as observed by Mr. Bromfield in his treatise of surgery.
2. Where an abscess is formed by the rupture of these new vessels, the
violence of inflammation ceases, and a new gland separates a material
called pus: at the same time a less degree of inflammation produces new
vessels called vulgarly proud flesh; which, if no bandage confines its
growth, nor any other circumstance promotes absorption in the wound, would
rise to a great height above the usual size of the part.
Hence the art of healing ulcers consists in producing a tendency to
absorption in the wound greater than the deposition. Thus when an
ill-conditioned ulcer separates a copious and thin discharge, by the use of
any stimulus, as of salts of lead, or mercury, or copper externally
applied, the discharge becomes diminished in quantity, and becomes thicker,
as the thinner parts are first absorbed.
But nothing so much contributes to increase the absorption in a wound as
covering the whole limb above the sore with a bandage, which should be
spread with some plaster, as with emplastrum de minio, to prevent it from
slipping. By this artificial tightness of the skin, the arterial pulsations
act with double their usual power in promoting the ascending current of the
fluid in the valvular lymphatics.
Internally the absorption from ulcers should be promoted first by
evacuation, then by opium, bark, mercury, steel.
3. Where the inflammation proceeds with greater violence or rapidity, that
is, when by the painful sensation a more inordinate activity of the organ
is produced, and by this great activity an additional quantity of painful
sensation follows in an increasing ratio, till the whole of the sensorial
power, or spirit of animation, in the part becomes exhausted, a
mortification ensues, as in a carbuncle, in inflammations of the bowels, in
the extremities of old people, or in the limbs of those who are brought
near a fire after having been much benumbed with cold. And from hence it
appears, why weak people are more subject to mortification than strong
ones, and why in weak persons less pain will produce mortification, namely,
because the sensorial power is sooner exhausted by any excess of activity.
I remember seeing a gentleman who had the preceding day travelled two
stages in a chaise with what he termed a bearable pain in his bowels; which
when I saw him had ceased rather suddenly, and without a passage through
him; his pulse was then weak, though not very quick; but as nothing which
he swallowed would continue in his stomach many minutes, I concluded that
the bowel was mortified; he died on the next day. It is usual for patients
sinking under the small-pox with mortified pustules, and with purple spots
intermixed, to complain of no pain, but to say they are pretty well to the
last moment.
_Recapitulation._
IV. When the motions of any part of the system, in consequence of previous
torpor, are performed with more energy than in the irritative fevers, a
disagreeable sensation is produced, and new actions of some part of the
system commence in consequence of this sensation conjointly with the
irritation: which motions constitute inflammation. If the fever be attended
with a strong pulse, as in pleurisy, or rheumatism, it is termed synocha
sensitiva, or sensitive fever with strong pulse; which is usually termed
inflammatory fever. If it be attended with weak pulse, it is termed typhus
sensitivus, or sensitive fever with weak pulse, or typhus gravior, or
putrid malignant fever.
The synocha sensitiva, or sensitive fever with strong pulse, is generally
attended with some topical inflammation, as in peripneumony, hepatitis, and
is accompanied with much coagulable lymph, or size; which rises to the
surface of the blood, when taken into a bason, as it cools; and which is
believed to be the increased mucous secretion from the coats of the
arteries, inspissated by a greater absorption of its aqueous and saline
part, and perhaps changed by its delay in the circulation.
The typhus sensitivus, or sensitive fever with weak pulse, is frequently
attended with delirium, which is caused by the deficiency of the quantity
of sensorial power, and with variety of cutaneous eruptions.
Inflammation is caused by the pains occasioned by excess of action, and not
by those pains which are occasioned by defect of action. These morbid
actions, which are thus produced by two sensorial powers, viz. by
irritation and sensation, secrete new living fibres, which elongate the old
vessels, or form new ones, and at the same time much heat is evolved from
these combinations. By the rupture of these vessels, or by a new
construction of their apertures, purulent matters are secreted of various
kinds; which are infectious the first time they are applied to the skin
beneath the cuticle, or swallowed with the saliva into the stomach. This
contagion acts not by its being absorbed into the circulation, but by the
sympathies, or associated actions, between the part first stimulated by the
contagious matter and the other parts of the system. Thus in the natural
small-pox the contagion is swallowed with the saliva, and by its stimulus
inflames the stomach; this variolous inflammation of the stomach increases
every day, like the circle round the puncture of an inoculated arm, till it
becomes great enough to disorder the circles of irritative and sensitive
motions, and thus produces fever-fits, with sickness and vomiting. Lastly,
after the cold paroxysm, or fit of torpor, of the stomach has increased for
two or three successive days, an inflammation of the skin commences in
points; which generally first appear upon the face, as the associated
actions between the skin of the face and that of the stomach have been more
frequently exerted together than those of any other parts of the external
surface.
Contagious matters, as those of the measles and small-pox, do not act upon
the system at the same time; but the progress of that which was last
received is delayed, till the action of the former infection ceases. All
kinds of matter, even that from common ulcers, are probably contagious the
first time they are inserted beneath the cuticle or swallowed into the
stomach; that is, as they were formed by certain morbid actions of the
extremities of the vessels, they have the power to excite similar morbid
actions in the extremities of other vessels, to which they are applied; and
these by sympathy, or associations of motion, excite similar morbid actions
in distant parts of the system, without entering the circulation; and hence
the blood of a patient in the small-pox will not give that disease by
inoculation to others.
When the new fibres or vessels become again absorbed into the circulation,
the inflammation ceases; which is promoted, after sufficient evacuations,
by external stimulants and bandages: but where the action of the vessels is
very great, a mortification of the part is liable to ensue, owing to the
exhaustion of sensorial power; which however occurs in weak people without
much pain, and without very violent previous inflammation; and, like
partial paralysis, may be esteemed one mode of natural death of old people,
a part dying before the whole.
* * * * *
SECT. XXXIV.
DISEASES OF VOLITION.
I. 1. _Volition defined. Motions termed involuntary are caused by
volition. Desires opposed to each other. Deliberation. Ass between two
hay-cocks. Saliva swallowed against one's desire. Voluntary motions
distinguished from those associated with sensitive motions._ 2. _Pains
from excess, and from defect of motion. No pain is felt during vehement
voluntary exertion; as in cold fits of ague, labour-pains, strangury,
tenesmus, vomiting, restlessness in fevers, convulsion of a wounded
muscle._ 3. _Of holding the breath and screaming in pain; why swine and
dogs cry out in pain, and not sheep and horses. Of grinning and biting
in pain; why mad animals bite others._ 4. _Epileptic convulsions
explained, why the fits begin with quivering of the under jaw, biting
the tongue, and setting the teeth; why the convulsive motions are
alternately relaxed. The phenomenon of laughter explained. Why children
cannot tickle themselves. How some have died from immoderate laughter._
5. _Of cataleptic spasms, of the locked jaw, of painful cramps._ 6.
_Syncope explained. Why no external objects are perceived in syncope._
7. _Of palsy and apoplexy from violent exertions. Case of Mrs. Scot.
From dancing, scating, swimming. Case of Mr. Nairn. Why palsies are not
always immediately preceded by violent exertions. Palsy and epilepsy
from diseased livers. Why the right arm more frequently paralytic than
the left. How paralytic limbs regain their motions._ II. _Diseases of
the sensual motions from excess or defect of voluntary exertion._ 1.
_Madness._ 2. _Distinguished from delirium._ 3. _Why mankind more
liable to insanity than brutes._ 4. _Suspicion. Want of shame, and of
cleanliness._ 5. _They bear cold, hunger, and fatigue. Charles XII. of
Sweden._ 6. _Pleasureable delirium, and insanity. Child riding on a
stick. Pains of martyrdom not felt._ 7. _Dropsy._ 8. _Inflammation
cured by insanity._ III. 1. _Pain relieved by reverie. Reverie is an
exertion of voluntary and sensitive motions._ 2. _Case of reverie._ 3.
_Lady supposed to have two souls._ 4. _Methods of relieving pain._
I. 1. Before we commence this Section on Diseased Voluntary Motions, it may
be necessary to premise, that the word volition is not used in this work
exactly in its common acceptation. Volition is said in Section V. to bear
the same analogy to desire and aversion, which sensation does to pleasure
and pain. And hence that, when desire or aversion produces any action of
the muscular fibres, or of the organs of sense, they are termed volition;
and the actions produced in consequence are termed voluntary actions.
Whence it appears, that motions of our muscles or ideas may be produced in
consequence of desire or aversion without our having the power to prevent
them, and yet these motions may be termed voluntary, according to our
definition of the word; though in common language they would be called
involuntary.
The objects of desire and aversion are generally at a distance, whereas
those of pleasure and pain are immediately acting upon our organs. Hence,
before desire or aversion are exerted, so as to cause any actions, there is
generally time for deliberation; which consists in discovering the means to
obtain the object of desire, or to avoid the object of aversion; or in
examining the good or bad consequences, which may result from them. In this
case it is evident, that we have a power to delay the proposed action, or
to perform it; and this power of choosing, whether we shall act or not, is
in common language expressed by the word volition, or will. Whereas in this
work the word volition means simply the active state of the sensorial
faculty in producing motion in consequence of desire or aversion: whether
we have the power of restraining that action, or not; that is, whether we
exert any actions in consequence of opposite desires or aversions, or not.
For if the objects of desire or aversion are present, there is no necessity
to investigate or compare the _means_ of obtaining them, nor do we always
deliberate about their consequences; that is, no deliberation necessarily
intervenes, and in consequence the power of choosing to act or not is not
exerted. It is probable, that this twofold use of the word volition in all
languages has confounded the metaphysicians, who have disputed about free
will and necessity. Whereas from the above analysis it would appear, that
during our sleep, we use no voluntary exertions at all; and in our waking
hours, that they are the consequence of desire or aversion.
To will is to act in consequence of desire; but to desire means to desire
something, even if that something be only to become free from the pain,
which causes the desire; for to desire nothing is not to desire; the word
desire, therefore, includes both the action and the object or motive; for
the object and motive of desire are the same thing. Hence to desire without
an object, that is, without a motive, is a solecism in language. As if one
should ask, if you could eat without food, or breathe without air.
From this account of volition it appears, that convulsions of the muscles,
as in epileptic fits, may in the common sense of that word be termed
involuntary; because no deliberation is interposed between the desire or
aversion and the consequent action; but in the sense of the word, as above
defined, they belong to the class of voluntary motions, as delivered in
Vol. II. Class III. If this use of the word be discordant to the ear of the
reader, the term morbid voluntary motions, or motions in consequence of
aversion, may be substituted in its stead.
If a person has a desire to be cured of the ague, and has at the same time
an aversion (or contrary desire) to swallowing an ounce of Peruvian bark;
he balances desire against desire, or aversion against aversion; and thus
he acquires the power of choosing, which is the common acceptation of the
word _willing_. But in the cold fit of ague, after having discovered that
the act of shuddering, or exerting the subcutaneous muscles, relieves the
pain of cold; he immediately exerts this act of volition, and shudders, as
soon as the pain and consequent aversion return, without any deliberation
intervening; yet is this act, as well as that of swallowing an ounce of the
bark, caused by volition; and that even though he endeavours in vain to
prevent it by a weaker contrary volition. This recalls to our minds the
story of the hungry ass between two hay-stacks, where the two desires are
supposed so exactly to counteract each other, that he goes to neither of
the stacks, but perishes by want. Now as two equal and opposite desires are
thus supposed to balance each other, and prevent all action, it follows,
that if one of these hay-stacks was suddenly removed, that the ass would
irresistibly be hurried to the other, which in the common use of the word
might be called an involuntary act; but which, in our acceptation of it,
would be classed amongst voluntary actions, as above explained.
Hence to deliberate is to compare opposing desires or aversions, and that
which is the most interesting at length prevails, and produces action.
Similar to this, where two pains oppose each other, the stronger or more
interesting one produces action; as in pleurisy the pain from suffocation
would produce expansion of the lungs, but the pain occasioned by extending
the inflamed membrane, which lines the chest, opposes this expansion, and
one or the other alternately prevails.
When any one moves his hand quickly near another person's eyes, the
eye-lids instantly close; this act in common language is termed
involuntary, as we have not time to deliberate or to exert any contrary
desire or aversion, but in this work it would be termed a voluntary act,
because it is caused by the faculty of volition, and after a few trials the
nictitation can be prevented by a contrary or opposing volition.
The power of opposing volitions is best exemplified in the story of Mutius
Scævola, who is said to have thrust his hand into the fire before Porcenna,
and to have suffered it to be consumed for having failed him in his attempt
on the life of that general. Here the aversion for the loss of same, or the
unsatisfied desire to serve his country, the two prevalent enthusiasms at
that time, were more powerful than the desire of withdrawing his hand,
which must be occasioned by the pain of combustion; of these opposing
volitions
Vincit amor patriæ, laudumque immensa cupido.
If any one is told not to swallow his saliva for a minute, he soon swallows
it contrary to his will, in the common sense of that word; but this also is
a voluntary action, as it is performed by the faculty of volition, and is
thus to be understood. When the power of volition is exerted on any of our
senses, they become more acute, as in our attempts to hear small noises in
the night. As explained in Section XIX. 6. Hence by our attention to the
fauces from our desire not to swallow our saliva; the fauces become more
sensible; and the stimulus of the saliva is followed by greater sensation,
and consequent desire of swallowing it. So that the desire or volition in
consequence of the increased sensation of the saliva is more powerful, than
the previous desire not to swallow it. See Vol. II. Deglutitio invita. In
the same manner if a modest man wishes not to want to make water, when he
is confined with ladies in a coach or an assembly-room; that very act of
volition induces the circumstance, which he wishes to avoid, as above
explained; insomuch that I once saw a partial insanity, which might be
called a voluntary diabetes, which was occasioned by the fear (and
consequent aversion) of not being able to make water at all.
It is further necessary to observe here, to prevent any confusion of
voluntary, with sensitive, or associate motions, that in all the instances
of violent efforts to relieve pain, those efforts are at first voluntary
exertions; but after they have been frequently repeated for the purpose of
relieving certain pains, they become associated with those pains, and cease
at those times to be subservient to the will; as in coughing, sneezing, and
strangury. Of these motions those which contribute to remove or dislodge
the offending cause, as the actions of the abdominal muscles in parturition
or in vomiting, though they were originally excited by volition, are in
this work termed sensitive motions; but those actions of the muscles or
organs of sense, which do not contribute to remove the offending cause, as
in general convulsions or in madness, are in this work termed voluntary
motions, or motions in consequence of aversion, though in common language
they are called involuntary ones. Those sensitive unrestrainable actions,
which contribute to remove the cause of pain are uniformly and invariably
exerted, as in coughing or sneezing; but those motions which are exerted in
consequence of aversion without contributing to remove the painful cause,
but only to prevent the sensation of it, as in epileptic, or cataleptic
fits, are not uniformly and invariably exerted, but change from one set of
muscles to another, as will be further explained; and may by this criterion
also be distinguished from the former.
At the same time those motions, which are excited by perpetual stimulus, or
by association with each other, or immediately by pleasureable or painful
sensation, may properly be termed involuntary motions, as those of the
heart and arteries; as the faculty of volition seldom affects those, except
when it exists in unnatural quantity, as in maniacal people.
2. It was observed in Section XIV. on the Production of Ideas, that those
parts of the system, which are usually termed the organs of sense, are
liable to be excited into pain by the excess of the stimulus of those
objects, which are by nature adapted to affect them; as of too great light,
sound, or pressure. But that these organs receive no pain from the defect
or absence of these stimuli, as in darkness or silence. But that our other
organs of perception, which have generally been called appetites, as of
hunger, thirst, want of heat, want of fresh air, are liable to be affected
with pain by the defect, as well as by the excess of their appropriated
stimuli.
This excess or defect of stimulus is however to be considered only as the
remote cause of the pain, the immediate cause being the excess or defect of
the natural action of the affected part, according to Sect. IV. 5. Hence
all the pains of the body may be divided into those from excess of motion,
and those from defect of motion; which distinction is of great importance
in the knowledge and the cure of many diseases. For as the pains from
excess of motion either gradually subside, or are in general succeeded by
inflammation; so those from defect of motion either gradually subside, or
are in general succeeded by convulsion, or madness. These pains are easily
distinguishable from each other by this circumstance, that the former are
attended with heat of the pained part, or of the whole body; whereas the
latter exists without increase of heat in the pained part, and is generally
attended with coldness of the extremities of the body; which is the true
criterion of what have been called nervous pains.
Thus when any acrid material, as snuff or lime, falls into the eye, pain
and inflammation and heat are produced from the excess of stimulus; but
violent hunger, hemicrania, or the clavus hystericus, are attended with
coldness of the extremities, and defect of circulation. When we are exposed
to great cold, the pain we experience from the deficiency of heat is
attended with a quiescence of the motions of the vascular system; so that
no inflammation is produced, but a great desire of heat, and a tremulous
motion of the subcutaneous muscles, which is properly a convulsion in
consequence of this pain from defect of the stimulus of heat.
It was before mentioned, that as sensation consists in certain movements of
the sensorium, beginning at some of the extremities of it, and propagated
to the central parts of it; so volition consists of certain other movements
of the sensorium, commencing in the central parts of it, and propagated to
some of its extremities. This idea of these two great powers of motion in
the animal machine is confirmed from observing, that they never exist in a
great degree or universally at the same time; for while we strongly exert
our voluntary motions, we cease to feel the pains or uneasinesses, which
occasioned us to exert them.
Hence during the time of fighting with fists or swords no pain is felt by
the combatants, till they cease to exert themselves. Thus in the beginning
of ague-fits the painful sensation of cold is diminished, while the patient
exerts himself in the shivering and gnashing of his teeth. He then ceases
to exert himself, and the pain of cold returns; and he is thus perpetually
induced to reiterate these exertions, from which he experiences a temporary
relief. The same occurs in labour-pains, the exertion of the parturient
woman relieves the violence of the pains for a time, which recur again soon
after she has ceased to use those exertions. The same is true in many other
painful diseases, as in the strangury, tenesmus, and the efforts of
vomiting; all these disagreeable sensations are diminished or removed for a
time by the various exertions they occasion, and recur alternately with
those exertions.
The restlessness in some fevers is an almost perpetual exertion of this
kind, excited to relieve some disagreeable sensations; the reciprocal
opposite exertions of a wounded worm, the alternate emprosthotonos and
opisthotonos of some spasmodic diseases, and the intervals of all
convulsions, from whatever cause, seem to be owing to this circumstance of
the laws of animation; that great or universal exertion cannot exist at the
same time with great or universal sensation, though they can exist
reciprocally; which is probably resolvable into the more general law, that
the whole sensorial power being expended in one mode of exertion, there is
none to spare for any other. Whence syncope, or temporary apoplexy,
succeeds to epileptic convulsions.
3. Hence when any violent pain afflicts us, of which we can neither avoid
nor remove the cause, we soon learn to endeavour to alleviate it, by
exerting some violent voluntary effort, as mentioned above; and are
naturally induced to use those muscles for this purpose, which have been in
the early periods of our lives most frequently or most powerfully exerted.
Now the first muscles, which infants use most frequently, are those of
respiration; and on this account we gain a habit of holding our breath, at
the same time that we use great efforts to exclude it, for this purpose of
alleviating unavoidable pain; or we press out our breath through a small
aperture of the larynx, and scream violently, when the pain is greater than
is relievable by the former mode of exertion. Thus children scream to
relieve any pain either of body or mind, as from anger, or fear of being
beaten.
Hence it is curious to observe, that those animals, who have more
frequently exerted their muscles of respiration violently, as in talking,
barking, or grunting, as children, dogs, hogs, scream much more, when they
are in pain, than those other animals, who use little or no language in
their common modes of life; as horses, sheep, and cows.
The next most frequent or most powerful efforts, which infants are first
tempted to produce, are those with the muscles in biting hard substances;
indeed the exertion of these muscles is very powerful in common
mastication, as appears from the pain we receive, if a bit of bone is
unexpectedly found amongst our softer food; and further appears from their
acting to so great mechanical disadvantage, particularly when we bite with
the incisores, or canine teeth; which are first formed, and thence are
first used to violent exertion.
Hence when a person is in great pain, the cause of which he cannot remove,
he sets his teeth firmly together, or bites some substance between them
with great vehemence, as another mode of violent exertion to produce a
temporary relief. Thus we have a proverb where no help can be had in pain,
"to grin and abide;" and the tortures of hell are said to be attended with
"gnashing of teeth."
Hence in violent spasmodic pains I have seen people bite not only their
tongues, but their arms or fingers, or those of the attendants, or any
object which was near them; and also strike, pinch, or tear, others or
themselves, particularly the part of their own body, which is painful at
the time. Soldiers, who die of painful wounds in battle, are said in Homer
to bite the ground. Thus also in the bellon, or colica saturnina, the
patients are said to bite their own flesh, and dogs in this disease to bite
up the ground they lie upon. It is probable that the great endeavours to
bite in mad dogs, and the violence of other mad animals, is owing to the
same cause.
4. If the efforts of our voluntary motions are exerted with still greater
energy for the relief of some disagreeable sensation, convulsions are
produced; as the various kinds of epilepsy, and in some hysteric paroxysms.
In all these diseases a pain, or disagreeable sensation is produced,
frequently by worms, or acidity in the bowels, or by a diseased nerve in
the side, or head, or by the pain of a diseased liver.
In some constitutions a more intolerable degree of pain is produced in some
part at a distance from the cause by sensitive association, as before
explained; these pains in such constitutions arise to so great a degree,
that I verily believe no artificial tortures could equal some, which I have
witnessed; and am confident life would not have long been preserved, unless
they had been soon diminished or removed by the universal convulsion of the
voluntary motions, or by temporary madness.