TO
DOCTOR BENJAMIN RUSH,
PROFESSOR OF CHEMISTRY, IN THE UNIVERSI-
TY OF PENNSYLVANIA.
SIR,
AS the following thesis contains physical observations
which do not appear to me to have been ever before
made on similar principles of natural philosophy, I there-
fore have justly considered no one more proper for me to
dedicate it to, than one whose distinguished abilities are so
celebrated, and universally known, that my researches up-
on the subject, should consequently become the more inte-
resting and satisfactory to the reader; but if you should
conceive there was just room for difference of opinion, I
should be glad to receive it, and annex it to this small pam-
phlet.
To be eminent in surgery, how natural is it to conclude,
that a man must be capable of performing with case and
address, the various important operations which fall with-
in the line of his province; at the same time we will con-
ceive him sufficiently well versed in all the systematic
branches of anatomy, &c. By the same rule, we will not
allow a man is a physician, because he attends the sick, and
prescribes remedies for them, unless he is capable of stat-
ing his cases, and making a report of his method of cure,
so as to give full satisfaction to any learned and approved
faculty of physicians: but indeed it is to be regretted there
is more room for pretenders to the latter, than to the for-
mer science.
The venerable Hippocrates has complained, that in his
days many hid their ignorance under ornaments of dress,
and strove to get the good liking of the people by their ap-
pearance at public games. But in those more enlightened
ages, it is not a little to be admired, why the legislature do
not take every possible means to prevent any such imposi-
tions in the healing art, which is so interesting to mankind
in general.
With profound respect and esteem, I am,
Your most obedient humble servant,
MICHAEL BOURKE,
Norfolk, Virginia, Feb. 10th, 1792. 



REVIEW, &c.
HAVING lately observed various fugitive pieces on
the hydrophobia, of little account, it particularly
drew my attention to a theme which appears to me to have
been but very little understood by most of those who have
attempted to treat upon it.
With astonishment I have observed them propose to con-
demn the practice of the ancients, without giving any suf-
ficient physical reasons, why their practice should be alto-
gether or in part abolished; for, the want of success, in
one or more cases, is not sufficient to reject it; unless the
particular state of different patients, differently treated,
could be exactly ascertained and stated; or otherwise an
error must be proved upon undeniable and known princi-
ples of natural philosophy. However, in the course of
these enquiries upon the subject, I shall endeavour to show
how far they were right, and how far wrong in this re-
spect, and at the same time, we will also take the practice
of the moderns into consideration, with a view to estab-
lish and make any amendment it would seem to admit of,
There are many methods of cure on record, in this dis-
order, said to be equally successful, but most of them are
rather chimerical and not to be depended upon; therefore,
it would tend rather to confuse than be of any real advan-
tage, to insert them. 

(6)
The morbid animal poison, which produces this dread-
ful disorder, causing no apparent change in the state of the
solids and fluids, as the other poisons of this class do, ex-
cept on the part to which it was first applied; from this,
one would naturally conclude, the evil was conveyed into
the constitution by means of the nervous fluid; and I am
persuaded, it was reflexions of this nature, that first led
Boerhaave and Mead to think so; I confess I was strongly
attached to this opinion too; but from the result of more
serious reflexion upon that head, I shall endeavour to prove
that the brain every where throughout the body, and the
cellular membrane, are the proper seat of it: for this is not
the only disorder of the brain and its productions, which
does not appear to effect any change in the substance of it
any where.
It is allowed by all, that the brain is the only sensible
part of the body, and that it is diffused over every moving
fibre, in form of a sensible mucus (which Kirkland calls it,
in his dissertation upon that organ) which fibres are con-
nected by means of the cellular membrane.
The canine virus coming in contact with the human
body, either in a dry or humid state, whether with or with-
out a wound, the stimulus it occasions is first felt and at-
tracted by the brain, and is received sooner or later, by
sympathy of affection, into the habit.
Dr. James, in his treatise on this subject, supposes the
cellular membrane is the receptacle of this as well as some
other infections: indeed it cannot admit of any doubt, that
those parts are the seat of it, from the exquisite degree of
sensibility always manifest in the poor patient; the organs
of his senses become so irritable and easily affected, that the
slightest breath of air, sound to the ear, and light to the eye
become painful and disagreeable.
This irritating cause, by affecting the vascular system in
general, causes a particular stricture on the vessels, which,
by increasing the action and reaction of the solids and fluids
one upon another, is always productive of those inflamma-
tory symptoms which are constantly attendant on this disor-
der; which stricture on the blood-vessels, which are every
where destined to feed the brain and nerves with animal
spirit, thus, by preventing the regular influx of this great
agent of life and motion into the interstices of the muscles
and other moving fibres of the body, spasms and convulsions
are produced. This animal æther, though derived from
matter(from the essence of our food, and from the circum-
ambient air we breathe) is so wonderfully spiritualized, 


(7)
that we know neither the nature nor consistence of it, as
being indiscernible, and incapable of being received by any 
artificial means; but still, we know in a great measure the
uses of it to the animal œconomy. I may justly say, it is this
subtile spirit, which receives the touch of electric fire, and
paries it through the body as quick as thought, which also
seems to be the cause of immediate and remote sympathy;
and from the following observations, I shall endeavour to
prove, that it is with it the all wise and mighty artist has
united that intelligent spirit which he was pleased to infuse
into the human body, so that a disorder being first produc-
ed, in that which I call the animal spirit, from the evil
effect of the canine virus received into the habit, the facul-
ties of the rational foul become so depraved, that towards
the close of this melancholy catastrophe, the wretched vic-
tim really thinks, at the approach of every violent paroxysm,
he is changed into a dog, which we may clearly understand
from his barking and snapping at his best friends, and foam-
ing at the mouth as those animals do in this disorder; and as
he finds this dreadful change coming upon him at intervals,
he warns his friends of it, and tells them to keep out of his
way.
Let us reflect for a moment, that the eternal wisdom in
all ages and at all times, doth preside over the actions of
men; and when we do or will to act contrary to the light
of understanding given us to avoid evil and do good, he
seems immediately to take notice of it, and informs the
body of the injustice done, either against him, or ourselves,
or others, by striking us with terror, and with a self-con-
viction of our own guilt; which more or less disorders the
whole frame, and throws every moving fibre into a state of
tremor and spasm, which not unfrequently destroys the ra-
tional faculties; and brings on lesser degrees of madness:
though still, I am persuaded that such disorders frequently
have many other remote and proximate causes, but still, as
they are most commonly spiritual, they almost always baffle
the use of medicine, which is God's second cause of health.
Thus the moral conduct has a good or evil tendency to-
wards the health of mind and body, which are evident
proofs of the existence of a just and all wise God.
After a nice examen and dissection of a person who died
of the hydrophobia, which Mr. Fauvrey had performed,
he gives us the following conjectural account.
" The nature of the poison is such, that it dissolves the bal-
" samic and nutricious parts of the blood, whence the veins
" are dried up, so as not easily to admit any blood from the 


(8)
" arteries, and the arterial blood by this means sustaining
" the action and impression of its vessels so long a time, is
" still further dissolved, attenuated and spiritualized, and
" thus sent in too great quantity and with too great rapidity
" to the brain, whence those convulsions and distractions,"
&c.
Although the dread of water is a symptom particularly
ascribed to this species of madness, still we find it is nei-
ther peculiar to it, nor always attendant on it, for it has
been observed that this remarkable symptom is proper to
some fevers and some particular inflammations, &c.
The smallest particle of the saliva of a mad dog is suffici-
ent to produce the infection, and if it should take effect, it
will first produce pain, inflammation, and ulceration oil
the part, before the terrible symptoms appear, though
the wound, if any there be, should entirely heal and
disappear; the neighbouring parts first begin to be
affected with pains similar to those in the rheumatism,
till by degrees the poison is received into the viscera
and vital parts. From the first there will be always
observable a constant conduction in the gullet, together
with a difficulty of swallowing. But if the patient is af-
fected at the sight of liquid, a horror seizes him, and if he
strives to drink, spasms are produced, with anxiety and loss
of sense; there is constantly a particular stricture and
heaviness on the breast, and a struggling, as it were, for
breath observed: a sighing, a nausea, and a vomiting, which
tightness and seeming weight upon the breast, increase to-
wards the close of this melancholy scene: an unusual flow of
saliva then comes on; an involuntary emission of semen and
priapism also: the fever and thirst increase; the urine be-
comes lixivious and in small quantities; the tongue hangs
out, and the mouth foams; the pulse becomes throbbing and
convulsive; the strength fails; cold sweats come on, and the
miserable patient soon expires in the spasms.
Although at present we are doubtful whether the ca-
nine poison is the effect of morbid action of the parts en-
dowed with life; or whether it proceeds from a more re-
mote cause, yet it is most probable, as dogs in general are
apt to feed upon putrid cadaverous substances with great
avidity, the gas which is separated from such in a pu-
trid or other evil state of fermentation in their stomachs
may be capable of producing such evil effects; it is also
very probable, the gastric juice with which those animals
are supplied, which enables them to dissolve and digest 


(9)
digest bones swallowed wholly and entire, contributes not
a little to the more speedy extrication and production of
this kind of mephitic air, in greater quantities, in a given
time, than could possibly be effected by a flower operation
of the like process in other animals, who are not possessed
of such a quick digesting menstruum.
Let us observe, that under similar circumstances, as to a
faulty digestion in the human body, approaching to an acid
or other evil state of fermentation in the stomach and pri-
mæ viæ; it is always productive of nervous disorders and
spasms, more or leas, and of low spirits: consequently the
more immediate, or proximate cause of those diseases, ad-
mits of a very striking analogy. Therefore, it is highly
probable, if we were to live less upon animal, and move
upon vegetable diet, disorders of this nature would be
less prevalent.
Dr. James has observed, that this kind of madness, pro-
perly belongs to the canine genus, consisting of three spe-
cies, viz. dogs, foxes, and wolves, to whom only it seems
inherent and natural, scarcely ever appearing in other ani-
mals, except it be inflicted by those of the dog kind.
Some are of opinion, the canine poison is of an acid,
and some again suppose it to be of an alkaline nature; but
from my ideas of the nature and first cause of it, I am strictly
in favour of the former opinion; admitting the existence
of ærial acid, derived from putrid animal substances, which
repels flame and extinguishes fire: in whatever shape, and
in whatever stomach it is generated, it always acts more or
less upon the living principle.
Dr. Seleg, who has written upon this subject, thinks the
pervagum and intercostal nerves, are the seat of this com-
plaint, because most of the symptoms happen where these
nerves are interspersed; from whence it appears that the
stomach is the principal and original seat.
By way of a caution to the reader, it may not be amiss
to insert the pathogmonic signs of madness in dogs, accor-
ding to Boerhaave, as follows. " He neither eats nor
drinks; he looks sad and fullen, and runs at any thing in
his way, whether man or beast, known, or unknown; with
a murmuring noise, but without barking, nodding as if he
was overpowered with sleep, and endeavouring to hide him-
self." Others also observe, that a dog not infected, upon
smelling the infected one, will shun him, and run away
with horror; and that those creatures will become disor-
dered if they go into kennels where mad dogs have been
kept; but it was never known that mankind received 
B

(10)
the infection any other way, than by coming in contact with
the poison.
It is very remarkable, that this animal virus sometimes
lies dormant for many months; but in general it appears in
three or four weeks: and if in six weeks no signs of the dis-
order appear, a person is usually concluded to be safe. How-
ever we have had instances of its appearing in two or three
days after the bite: yet there are also instances, well attes-
ted, in which, one or two years have elapsed before it had
taken place, which, though it should seem curious and mys-
terious in this disorder, I think it is no less observable in the
small pox, measles, venereal disease, and in short, in all
other kinds of malignant infection, or contagious miasma-
ta floating in the atmosphere. These phenomena, I shall
take upon me to explain as follows, although I have never
known either ancient or modern writers to say any thing
satisfactory upon that head.
If we turn our thoughts on chemistry, we may see how
many various operations of it tend to prove that there is a
power in bodies, properly called repulsion, which prevents
them from uniting together, after they have approached
each other to a certain point, which is as real and as absolute
as the power of attraction. Though still from changes inci-
dent to matter, it is, under such circumstances, still subject
to the laws of attraction. That those respective powers are
as proper to the living subject, as to other material bodies,
cannot be denied from the following observations, and I be-
lieve the one to be equally various with the other. How
evident does the power of repulsion appear in local gan-
grenes, where we see the chemical properties of the found
and living parts form a separating action from those of the
morbid and unsound: the found and elastic fibre, by the force
of cohesion, preserving its natural form and shape: and the ra-
refying effect of fire in the circumambient air, the bulk of the
fluid parts being incessantly enlarged; the fire acting by
pulsation, as well as distension, it constantly excites the elastic
fibre to action, and so maintains motion and vital heat. In
spacelous or gangrenous cases, one part of the living sub-
ject preserves life and motion, whilst a dissolution and de-
struction ensues in another, by losing its fixed air, after a
species of fermentation is commenced, although the air is a
common medium by which the union of parts is preserved,
still, if it was received into the found parts, it would pro-
mote a like dissolution and destruction there. But those
found and living parts are still preserved from its destruc- 


(11)
live quality, by their retaining due degrees of density and
cohesion in their own component parts.
Let us further observe, that the tender and delicate con-
stitution of the solids, not oppressed with gross humours, is
exquisitely sensible, if unattended with any disorder in the
brain or nerves, which acuteness of sensibility is various in
different habits and climates, as the former are more or
less full; and as it approaches to greater or lesser degrees,
the sympathy of affection and symptoms appear sooner or
later.
The tense and lax fibre we know are by nature predispo-
sed to favour the proximate cause of disease, the former by
exciting too much heat, and the latter too little in the ani-
mal economy; but when it is so happily disposed as to be
neither too tense nor lax, the offices of secretion and excre-
tion are in such state well and duly performed; because the
heat of the body consequently falls between extremes
which constitute that salutary state in which we are less sus-
ceptible of the remote cause of disease.
Cullen distinguishes two species of this disorder. The hy-
drophobia rabiosa, when there is a desire of biting, and
the hydrophobia simplex, when there is not any such de-
sire.
Celsus, Galen, Mead, and Etmuller, all recommend in
this, as well as in other venomous cases, to enlarge she
wound made by the bite, by a circular incision and scarifica-
tion, to apply a cautery to it, and keep it open for at least
forty days: but as this method appears rather too harsh, I
shall beg leave to advise a far preferable one, which is by
the moderns now considered as a specific; they scarify the
part, and sprinkle cantharides every second or third day
into the wound, and keep it open for a considerable time.
But if the poison is first received on a bony or tendinous
part, I would by all means recommend the practice of the
people of Connecticut—for, it is confidently said, they ne-
ver have experienced any ill effects in such cases, from their
usual treatment. They rub a handful of salt and water well
on the part, and lay a parcel of salt thereon, and wrap it
up in different folds of a wet cloth, dipt in the same salt
water.
Under this head I shall also mention the following in-
stance of a cure, which is really worth notice, which was
taken from the records of the British royal academy of sci-
ences. A maid of twenty years of age, having all the symp-
toms, was bathed in a tub of river water, wherein a bushel
of salt had been dissolved; they plunged her in naked, again 


(12)
and again, till harrassed almost to death; they then left her
fitting in it quite senseless: when she came to herself, she was
surprised to find herself looking at the water without any
concern.
I am of opinion that this practice may be used with
great advantage in far advanced and desperate cases; pro-
vided the person was of a lax and loose habit of body (as
to the constitution of the solids) but if it should happen to
be the reverse, I think the patient might be prepared for
the salt bath by blood letting. From the nature and pene-
trability of sea salt, it does not appear to me, that there is
any method that promises such a speedy relief as this; it
is calculated not only to counteract the evil tendency of
the poison, but also to supply the defect of vital heat, and
support the exhausting strength, without breaking the
crasis of the fluids, as mercury does.
And what is still more persuasive, the frequent and sud-
den plunging of the patient over head and ears in sea wa-
ter, after the bite, has been generally reckoned to be the
best and surest preservative in this disease. In those advanc-
ed stages when the poison seems to be received into the vi-
tal parts, there is no probability of succeeding with mercu-
ry, though it is most commonly received into practice, in
the cure of this malady.
Alexipharmic drinks, with testaceous powders, were so
much extolled among the ancient physicians, that Galen af-
firmed nobody had ever died, who used this remedy: these
absorbent earths were to be taken every day for forty days
successively, either alone or with Gentian root and Frank-
incense in wine.
The ancients having most commonly practised blood let-
ting, in such cases, perhaps their method of cure, princi-
pally on this account, was the best; which I am persua-
ded, they had advised, rather to keep the patient low, and
his strength under; than that they ever supposed a pletho-
ra or redundance of humours had any share in them.
It is certain, that where a stricture lies upon the ves-
sels from an irritating cause, as I have before sufficiently
stated, the bulk of the humour must be lessened by vene-
section, to bring on a relaxation, and so give a free and ea-
sy influx to fresh animal spirit into the interstices of the
muscles, and facilitate the progress of the cure by the help
of proper remedies.
This is not the only case in which we are not to depend
upon the pulse with respect to blood letting. In some ple-
thoric cases, the vessels are so overcharged and distended 


(13)
beyond their natural degree of contraction, and their tonic
powers fo impeded, that the pulsation is scarcely to be felt,
without any appearances of an acute or inflammatory dis-
order: but we must have other convincing proofs of ple-
thora, before this serious and delicate operation should be
performed.
I am more particular on this point, becaufe there are so
many various opinions for and against the necessity of blood-
letting in the hydrophobia.
From the assertions of the ancients, and their rational me-
thod of cure, I am persuaded that the acrimony peculiar to
this disease, may be destroyed more ways than one.
To those who are but little skilled in physics, it may ap-
pear, that there are various ways and means by which we
may relieve one and the like complaint, proceeding from a
defect of the vital heat; still, such ways and means must
not differ essentially in nature, to accomplish the great de-
sign of assisting and supporting the living principle. This
comparison holds good with respect to the former observa-
tion.
It must be the like case in this disorder, as in others;
when it is far advanced, there are but very faint hopes of
success; however, although the symptoms of subsultus ten-
dinum are present, we must still see what art can do; let
blood first, and repeat the operation, till the patient faints;
the next day try the salt bath, and after two or three days
repetition, apply the strong mercurial ointment by friction,
so as to raise a very gentle ptyalism, give opium and anti-
monials or other perspiratives, to relieve spasmodic stric-
ture; and keep the patient principally upon a milk and
vegetable diet, with ripe and acetous fruits, and allow a
moderate use of generous wines: and when occasion shall
require to loosen the belly, or free it from any acrid mat-
ter it may be troubled with, it is best to be done by injec-
tion or some very mild and gentle aperient. The sore, or
part whereon the poison was first received, may be treated
as before directed.
A frequent use of the warm bath is inadmissible; because
it debilitates the habit, and renders it unfit for taking pro-
per means. Although it gives a temporary relief in spasmo-
dic stricture, the evil consequences it is afterwards atten-
ed with, by far exceed any good it may do otherwise.
THE END.