[THIS little piece was written about the end of the winter
1793-4, on the occasion of a growing alarm of the yellow fever
being again in Philadelphia. Fear began to spread in the city;
and, had it extended to the members of the national legislature,
so as to have occasioned their removal from town, it would have        
been attended with considerable disadvantage to the public affairs.
Copies were distributed among the gentlemen of congress, and to a
few of the city. But it happened that several, who could not
have been purposely overlooked, did not receive any: and appli-
cations have been made for copies when there were none left. To
answer these, a few copies more, with notes, are struck off.]
YELLOW FEVER. 
THE yellow fever, or tropical endemic causus,
and the small pox, are inflammatory in the attack;
and are communicated by specific contagion. The
poison of the former, as it seems, is conveyed di-
rectly to the stomach with the saliva, or any thing
swallowed, and acts upon it, and upon the pylorus
and duodenum, by corrosion; which first raising an
inflammation on the parts, these afterwards become
gangrenous. This poison acts as other acrid poisons
taken into the stomach. The disease is a corrosion
of the stomach, the pylorus, and the duodenum; all
else of the complaints, are they more than symptoms
consequent of that corrosion? *
The contagious poison of the small pox acts more
like that infused into the blood by the bite of poison-
ous animals, which contaminates the mass.
The constituent parts of these poisons, or by what
process of nature they are generated, few pretend to
know; and though some may fancy they know them,
yet it is beyond the conjecture of most.
* See an account of dissections, page 9. 


[2]
Whilst we are ignorant of the cause of the yellow
fever and small pox, we may however admit that they
are infectious, though not alike in all circumstances.*
The small pox may be communicated in all states of
the air, but the yellow fever can exist only in a hot
air, as histories of it show: and there are also strong
reasons for believing from those histories, that frost
kills the infectious matter of it, as surely as it kills
certain other exotics. Many people, in the time of
the late epidemic in Philadelphia, looked for rain,
* The tropical endemic yellow fever is not always conta-
gious. It exists in the West India islands for years together
without being notably so. Strangers from northern climates
are very liable to take it on their arrival there; and it goes
hard with them. Their being so very susceptible, is owing
more to their intemperance, and exposure to night air, dews
and rains, than to contagion. After some number of years,
it is ushered in with aggravated circumstances. It thus be-
comes very contagious, and is a distinct and most fatal disease.
Such was the yellow fever in Philadelphia in 1793, and in
the West Indies in 1793 and 1794. The milder or common
yellow fever of the islands can never be conveyed to the con-
tinent, because it is not contagious, and the contagious kind
seldom exists in the islands:—thence the long intervals of its
appearance on this continent. All plagues have their periods.
When the peculiar circumstances that occasion or admit of
the aggravation in the yellow fever give way, the disease
becomes no longer contagious, but sinks into the common
and less virulent tropical yellow fever. It is said, an excess
of heat or of cold will destroy certain diseases. The dreaded
Natolian plague (commonly called "The Plague") has ex-
isted, at times, in the higher but mild latitudes, hitherto,
without having ever originated any where else than in Na-
tolia. It is often in northern Egypt and on the coast of
Barbary: but it is said to be always carried thither from its
Natolian source. M. Savery calls Constantinople and Smyrna
the Foci of it. Was this kind of plague ever known to exist 


[3]
which they believed would be fatal to the infection.*
Others regarded not the coming of rain, otherwise
than as it might be attended with or followed by cold;
and they looked only for mere cold, whether attended
with rain or not, because histories of this fever assured
them that cold had always been fatal to the infection.
It is admitted that floods of rain, by diluting and
washing off the stagnant putrid water of a low
country, relieve from the remitting, the bilious,
and the putrid fevers common to such countries.
Although the yellow fever originates in countries
of perpetual beat, yet it may be brought from thence
into this country of both cold and heat, as it hereto-
fore has been: there are, however, two particulars
especially necessary to that end; that it be in the
peculiar air of a large town, and that the season be hot.
It may well be presumed it cannot act, in this country
at least, but under this combination; because it ne-
ver yet has appeared on the continent, unattended
between the tropics? It has been earned to England, and
other countries of heat and cold, where it raged. All the
countries of its existence are in the temperate climates. Did
it ever exist in countries of continual heat? On the other
hand, the yellow fever, in its virulent state, originates
only within the tropics, the lower latitudes of perpetual
heat: but it is of a nature to act in the higher latitudes, under
a combination of certain peculiar circumstances, when in-
troduced from its native source. There must be such a
combination to produce and support these contagious and
dreadful diseases. Other circumstances arrest, and in the
end annihilate them.
* In Granada, "As the change to moisture was remark-
ably great and sudden, much expectation was formed that
the virulence of the infection would be done away or abated:
but neither happened." Chisholm. 


[4]
with those circumstances. If the matter of this con-
tagion suffers cold, it suffers death; as may be col-
lected from facts uniformly heretofore happening in
this country. When it was in Charleston, S. C. in
1748, it received its death stroke from cold air on
the fourteenth of October; and about the same time
of October it lately experienced the like, on the
change of air from an uncommon heat, for that
season, to the proper degree of autumnal cold. The
cool air, especially at night, in the last week of
September, 1793, produced such a change in the
degree of infection and complaints of the sick in
Philadelphia, that the physicians expressed an agree-
able surprize, on the great abatement of both: but
the return of warm close weather, with a shift of
wind from the northern quarters to the southern, in
the beginning of October, gave so fatal a malignancy
to the disease, as occasioned more frequent deaths,
for some days, even after the return of cooler wea-
ther; but, it seems it had generally effected too
much to admit of recovery, of the then sick, in any
state of the air afterwards.
For supporting the aforegoing principles, we need
only be assured that the yellow fever has never been
communicated in country places or small towns on
this continent; and that as often as it has been
amongst us, it always appeared to be imported,
always vanished in the cool season of autumn'
and never recurred with the ensuing summer, nor
until again ushered in from the West Indies. Re-
ports say indeed, that it has been taken in country
places, in some few instances. But on inquiry, it
appears there has been a want of knowledge to
distinguish the yellow fever from diseases of the  


[5]
country, the symptoms being partly alike. In other
instances, people have received the infection in
Philadelphia, but have pretended they had not been
in the city: others alarmed, have imagined they had
it, when they have only had a little cold or common
complaint, or mere apprehension may have induced
the supposition.*
People and merchandise have been continually
arriving from the West India islands, the source of
the yellow fever for ages past; yet the disease was
never communicated to the people of this city, but in
the heat of summer, and that only thrice in above
sixty years; probably the seldomer, from the con-
tagious matter having generally spent itself, or eva-
porated in the time of performing the voyages.
* It seems there still is a suspicion in some physicians,
founded on the narrations of other people, that there were a
few instances of the infection taken in country places. But
to ascertain facts of this nature, and distinguish them with
accuracy, for a physician to judge of them with certainty, is
not very easy in common. Diseases originating in or greatly
affecting the stomach, are attended with symptoms much
alike, from the common intermittent to the yellow fever.
Any thing corrosive or acrimonious, acting forcibly on the
coats of that bowel, must immediately affect the nerves,
which there abound, and readily communicate sensations to
the very extremities. The beginning of the worst of the
yellow fever has been taken, in Philadelphia, for only a
cold or obstructed perspiration. Perspiration, by the bye,
being refused a passage through its natural outlet, becomes
depraved and even acrimonious. It then soon affects the
fibres and the nerves, and induces spasm (whether it be
perceptible or not) attended with tremours, head-ach, hea-
viness, restlessness, anxiety, pains, nausea or vomiting. If
haply the perspirabie matter is driven into the canal, it is 


[6]
To satisfy the mind that the late epidemic, in
Philadelphia, was introduced from a tropical climate,
sober reason requires but to know, that it is a disease
natural to the West India islands; that it never was
known to originate in this country; but has been
admitted, without a doubt of any one till now, to
have been always brought from thence; that it has
been, this year, raging in those islands more than
usual; that there never was before such a plenty of
means for bringing it from thence, and that it first
broke out in a part of the city near which ships from
those islands, that had unusual numbers of sick peo-
ple on board, discharged their cargoes. From all
which circumstances there arises an irresistible pre-
sumption, that the late contagious fever, called the
yellow fever, was imported from the West India
islands.*
thence discharged in the character of diarrhœa. But, if its
stimulous produces fixed spasm on the intestines, whilst the
pores of the skin still remain closed, costiveness then occurs,
and the perspirable matter is every way shut up. It seems,
that from the spasm of the stomach, extended, arises the
costiveness usual in the yellow fever; which remains, till
recovery or putrefaction releases the fibres from the spasm.
When putrefaction happens to effect this—then it is that by-
standers become astonished on seeing the spontaneous dis-
charges, which are immense, in fluids that had been accu-
mulating, and were imprisoned by the spasm now suddenly
let loose on an entire loss of tone in the fibres.
* The introduction of the yellow fever from Boullam,
in Africa, into St. George's, in Granada, was by the
ship Hankey, in February, in the year 1793, and
it was called the "Boullam fever" or "Boullam malig-
nant pestilential fever." Doctor Chisholm thinks it is
the same with that which raged in Philadelphia in that year. 


[7]
It has been inconsiderately imputed to Philadel-
phia, that it is more liable to receive the yellow
fever than other large towns of America. It is made
by people who had collected from recent hasty pub-
lications, that it had been three or four times in this
city, without their being informed how often it had
been in other towns. This fever, it seems, has been
at least as often in Charleston, S. C. and New York.
The accurate doctor Lining speaks of four times that
it was in Charleston; in the years 1732, '39, '45, and
'48. Charleston being nearer the ocean, the tropic,
the Havanna, and the West India islands, seems more
liable to receive the infection than a town further
from them, and near a hundred miles inland, that in
general is remarkably healthful, and which would
He illustrates this idea by the instance of a vessel, belonging
to Philadelphia, introducing the disease into St. Pierre,
Martinique, in October, 1793, and by a vessel from New
London touching at St. Pierre, and carrying the infection to
Granada in February, 1794. He adds, that on the sick
being put under his charge, he found the disease was his old
enemy, the malignant pestilential fever, (meaning no doubt
the same with that introduced from Boullam into Granada in
the preceding February) which he successfully treated with
mercury. It raged in Granada in 1793, and generally
among the West India islands, more or less, through that
and the next following year.
The Boullam fever, in 1793, February, was imported
into Granada from Boullam. In July following, into Phi-
ladelphia from the West India islands. In October following,
into Martinique from Philadelphia. Being identically the
same in qualities, it was as readily returned from hence to the
islands, as it was at first brought from thence to the great
towns of the continent. A vessel of Philadelphia lost her
supercargo at Granada, who died there of the Boullam fever
so early as April, 1793. 


[8]
probably scarcely ever receive it, were it not that it is
more populous, and therefore has more ot the air
peculiar to large towns, which is so necessary, toge-
ther with the heat of a summer, to give action to the
contagious matter, on its speedy arrival fresh from
its tropical source.
It is also said that the yellow fever has been intro-
duced into this country in ships from Rotterdam and
Ireland, crouded with passengers: but this a great
mistake. The hospital fever has often been intro-
duced by them into America, but never once the
yellow fever, which is not a disease of northern
climates. The hospital or gaol fever is thought to
arise from animal effluvia. Prisons, hospitals and
ships are crouded with men, and abound with excre-
mentitious animal effluvia pent up from fresh air. The
gaol fever is peculiar to such places, and is very
infectious.
It is wished those persons who are apprehensive
that contagious matter of the yellow fever is wrapped
up in furniture, and they know not what, and that
it will break out next summer, would be at the pains
to inform themselves, from the histories of the
disease heretofore published, of the manner and the
time when it usually arrived or broke out, and when
it died away on this continent. It will pacify them.
They will especially be assured that some number of
years passed away between the times of its recurring
in our country.

[9]
THE public obliged to doctors Physick and
Cathrall for an account, early given, of their dis-
sections of persons who died of the yellow fever
which raged in Philadelphia in the year 1793; the
purport whereof follows, together with remarks
thereon by the editor.
B.
1. The brain in all its parts, has been found in a natural
condition.
Remark. The disease is local to the stomach and parts near
it. The brain is distant from the seat of it. The first, se-
cond, third and ninth of the following instances of dissection
were of such persons as died early in the disease. Note well
the ninth observation of the doctors.
2. The viscera of the thorax are perfectly sound. The
blood however, in the heart and veins, is fluid; similar in its
consistence to the blood of persons who have been hanged or  
destroyed by electricity.
Remark. The early death from spasm of the stomach—
a stroke local that effects not general disease, may account for
this: and moreover, in hot weather coagulation occurs not
very soon.
3. The stomach and beginning of the duodenum are the
parts that appear the most diseased. In two persons who died
of the disease on the fifth day, the villous membrane of the
stomach, especially about its smaller end, was found highly
inflamed, and this inflammation extended through the pylorus
into the duodenum, some way. The inflammation here was
exactly similar to that induced in the stomach by acrid poi-
sons; as by arsenic, which we have once had an opportunity
of seeing in a person destroyed by it.
Remark. this illustrates the reality of the matter of a
specific contagion acting immediately on the stomach. A part
where of may tend downward, and here and there attach to the
intestines. If some of it is, in certain cases, enveloped in the
passing excrement, so as to be carried off at the common outlet,
B 


[10]
yet enough of it may adhere, and act on the bowels to the worst
purposes.
4. The bile in the gall bladder was quite of its natural
colour, though very viscid.
Remark. The fluids are not the immediate subjects of this
disease.—The preceding are in instances of early deaths,
in the state of a contraction or inflammation of the stomach,
The following are of later deaths, where gangrene has oc-
curred, after the inflammatory state.
5. In a person who died on the eighth day of the disease,
several spots of extravasations were discovered between the
membranes, particularly about the smaller end of the sto-
mach, the inflammation of which had considerably abated.
Pus was seen in the beginning of the duodenum, and the
villous membrane of this part was thickened.
Remark. The inflammation abates as gangrene approaches.
Was not the production of pus owing to an effort of health?
The thickening was an indication of putrefaction.
6. In two other persons who died at a more advanced
period of the disease, the stomach appeared spotted in many
places with extravasations, and the inflammation disappeared.
It contained, as did also the intestines, a black liquor, such
as had been vomited and purged before death.—This black
liquor appears clearly to be an altered secretion from the
liver: for, a fluid in all respects of the same qualities was
found in the gall bladder. This liquor was so acrid that it
induced considerable inflammation and swelling on the ope-
rator's hands, which remained some days. The villous
membrane of the intestines, in these last two bodies, was
found inflamed in several places.
Remark. The effects of the poison, though mostly local to
the stomach and duodenum, sometimes appear in other parts of
the bowels; and they act destructively where there is the rea-
diest susceptibility. The poison first is in contact with the
stomach: and after having effected. a corrosion and inflammation
there, which is followed by a gangrene of that bowel, it or
some part of it may descend, as it seems, and raise an inflam-
mation on the inferior bowels, where it chances to adhere, even 


[11]
after the stomach is destroyed. The general mass is not imme-
diately contaminated by the attack on the stomach, so as to be-
come gangrenous or putrid: otherwise, could a subsequent in-
flammation be produced on the other bowels?              
7. The liver was of its natural appearance, excepting in
one of the last persons, on the surface of which a very few
distended veins were seen, although other abdominal viscera
were of healthy appearance.
Remark. The spasms and corrosions of the stomach are con-
siderable. Such as must soon induce general disorder of the
body, and extensive morbid effect, both in the solids and the
fluids, though not always alike or in the same parts.
8. The external surface of the stomach, as well as of the
intestines, was quite free from the inflammation; the veins
being distended with blood, which appeared through the
transparent peritoneum, gave them a dark colour.
Remark. This is further in favour of the locality of this
disease. How confined!—All is effected first by contact with
the fibres and nerves of the stomach. The symptoms were dis-
fuse; and in the end the fluids with the solids become exten-
sively morbid.
9. The stomach of those who died early in the disease, was
always contracted: but in those who died in a more advanced
period of it, where extravasations appeared, it was distended
with air.
Remark. The corrosive poison early injures the fibres of the
stomach, and occasions spasm; first of the minuter parts with
which it comes into contact; and this presently extends so con-
siderably and so forcibly as to contract the whole or a great
part of that bowel, during the inflammatory state, and until
gangrene dissolves the contraction of the fibres. The consequent
putrefaction is then attended with a distension of the parts.
Such sudden, strong, and extensive contraction must arrest the
natural and necessary functions: and death comes with speed,
before time is given for gangrene to effect it.