I. The blood-vessels were affected more or less in every case of this fever. I have elsewhere said, that a fever is occasioned by a convulsion in the arterial system[16]. When the epidemic, which we are now considering, came on with a full, tense, and quick pulse, this convulsion was very perceptible; but it frequently came on with a weak pulse, often without any preternatural frequency or quickness, and sometimes so low as not to be perceived without pressing the artery at the wrists. In many cases the pulse intermitted after the fourth, in some after the fifth, and in others after the fourteenth stroke. These intermissions occurred in several persons who were infected, but who were not confined by the fever. They likewise continued in several of my patients for many days after their recovery. This was the case in particular in Mrs. Clymer, Mrs. Palmer's son William, and in a son of Mr. William Compton. In some, there was a preternatural slowness of the pulse. It beat 44 strokes in a minute in Mr. B. W. Morris, 48 in Mr. Thomas Wharton, jun. and 64 in Mr. William Sansom, at a time when they were in the most imminent danger. Dr. Physick informed me, that in one of his patients the pulse was reduced in frequency to 30 strokes in a minute. All these different states of the pulse have been taken notice of by authors who have described pestilential fevers[17]. They have been improperly ascribed to the absence of fever: I would rather suppose that they are occasioned by the stimulus of the remote cause acting upon the arteries with too much force to admit of their being excited into quick and convulsive motions. The remedy which removed it (to be mentioned hereafter) will render this explanation of its cause still more probable. Milton describes a darkness from an excess of light. In like manner we observe, in this small, intermitting, and slow pulse, a deficiency of strength from an excess of force applied to it. In nearly every case of it which came under my notice, it was likewise tense or chorded. This species of pulse occurred chiefly in the month of August, and in the first ten days in September. I had met with it formerly in a sporadic case of yellow fever. It was new to all my pupils. One of them, Mr. Washington, gave it the name of the “undescribable pulse.” It aided in determining the character of this fever before the common bilious remittent disappeared in the city. For a while, I ascribed this peculiarity in the pulse, more especially its slowness, to an affection of the brain only, and suspected that it was produced by what I have taken the liberty elsewhere to call the phrenicula, or inflammatory state of the internal dropsy of the brain, and which I have remarked to be an occasional symptom and consequence of remitting fever. I was the more disposed to adopt this opinion, from perceiving this slow, chorded, and intermitting pulse more frequently in children than in adults. Impressed with this idea, I requested Mr. Coxe, one of my pupils, to assist me in examining the state of the eyes. For two days we discovered no change in them, but on the third day after we began to inspect them, we both perceived a preternatural dilatation of the pupils, in different patients; and we seldom afterwards saw an eye in which it was absent. In Dr. Say it was attended by a squinting, a symptom which marks a high degree of a morbid affection of the brain. Had this slowness or intermission in the pulse occurred only after signs of inflammation or congestion had appeared in the brain, I should have supposed that it had been derived wholly from that cause; but I well recollect having felt it several days before I could discover the least change in the pupil of the eye. I am forced therefore to call in the operation of another cause, to assist in accounting for this state of the pulse, and this I take to be a spasmodic affection, accompanied with preternatural dilatation or contraction of the heart. Lieutaud mentions this species of pulse in several places, as occurring with an undue enlargement of that muscle[18]. Dr. Ferriar describes a case, in which a low, irregular, intermitting, and hardly perceptible pulse attended a morbid dilatation of the heart[19]. In a letter I received from Mr. Hugh Ferguson, then a student of medicine in the college of Edinburgh, written from Dublin, during the time of a visit to his father, and dated September 30th, 1793, I find a fact which throws additional light upon this subject. “A case (says my young correspondent) where a remarkable intermission of pulse was observed, occurred in this city last year. A gentleman of the medical profession, middle aged, of a delicate habit of body, and who had formerly suffered phthisical attacks, was attacked with the acute rheumatism. Some days after he was taken ill, he complained of uncommon fulness, and a very peculiar kind of sensation about the præcordia, which it was judged proper to relieve by copious blood-letting. This being done, the uneasiness went off. It returned, however, three or four times, and was as often relieved by bleeding. During each of his fits (if I may call them so), the patient experienced an almost total remission of his pains in his limbs; but they returned with equal or greater violence after blood-letting. During the fit there was an intermission of the pulse (the first time) of no less than thirteen strokes. It was when beating full, strong, and slow. The third intermission was of nine strokes. The gentleman soon recovered, and has enjoyed good health for ten months past. The opinion of some of his physicians was, that the heart was affected, as a muscle, by the rheumatism, and alternated with the limbs.”
I am the more inclined to believe the peculiarity in the pulse which has been mentioned in the yellow fever, arose in part from a spasmodic affection of the heart, from the frequency of an uncommon palpitation of this muscle, which I discovered in this disease, more especially in old people. The disposition, likewise, to syncope and sighing, which so often occurred, can be explained upon no other principle than inflammation, spasm, dilatation, or congestion in the heart. After the 10th of September this undescribable or sulky pulse (for by the latter epithet I sometimes called it) became less observable, and, in proportion as the weather became cool, it totally disappeared. It was gradually succeeded by a pulse full, tense, quick, and as frequent as in pleurisy or rheumatism. It differed, however, from a pleuritic or rheumatic pulse, in imparting a very different sensation to the fingers. No two strokes seemed to be exactly alike. Its action was of a hobbling nature. It was at this time so familiar to me that I think I could have distinguished the disease by it without seeing the patient. It was remarkable that this pulse attended the yellow fever even when it appeared in the mild form of an intermittent, and in those cases where the patients were able to walk about or go abroad. It was nearly as tense in the remissions and intermissions of the fever as it was in the exacerbations. It was an alarming symptom, and when the only remedy which was effectual to remove it was neglected, such a change in the system was induced as frequently brought on death in a few days.
This change of the pulse, from extreme lowness to fulness and activity, appeared to be owing to the diminution of the heat of the weather, which, by its stimulus, added to that of the remote cause, had induced those symptoms of depression of the pulse which have been mentioned.
The pulse most frequently lessened in its fulness, and became gradually weak, frequent, and imperceptible before death, but I met with several cases in which it was full, active, and even tense in the last hours of life.
Hæmorrhages belong to the symptoms of this fever as they appeared in the sanguiferous system. They occurred in the beginning of the disease, chiefly from the nose and uterus. Sometimes but a few drops of blood distilled from the nose. The menses were unusual in their quantity when they appeared at their stated periods, but they often came on a week or two before the usual time of their appearance. I saw one case of a hæmorrhage from the lungs on the first day of the fever, which was supposed to be a common hæmoptysis. As the disease advanced the discharges of blood became more universal. They occurred from the gums, ears, stomach, bowels, and urinary passages. Drops of blood issued from the inner canthus of the left eye of Mr. Josiah Coates. Dr. Woodhouse attended a lady who bled from the holes in her ears which had been made by ear-rings. Many bled from the orifices which had been made by bleeding, several days after they appeared to have been healed, and some from wounds which had been made in veins in unsuccessful attempts to draw blood. These last hæmorrhages were very troublesome, and in some cases precipitated death.
II. I come now to mention the symptoms of this fever as they appeared in the liver, the lungs, and the brain. From the histories which I had read of this disease, I was early led to examine the state of the liver, but I was surprised to find so few marks of hepatic affection. I met with but two cases in which the patient could lie only on the right side. Many complained of a dull pain in the region of the liver, but very few complained, in the beginning of the disease, of that soreness to the touch, about the pit of the stomach, which is taken notice of by authors, and which was universal in the yellow fever in 1762. In proportion as the cool weather advanced, a preternatural determination of the blood took place chiefly to the lungs and brain. Many were affected with pneumonic symptoms, and some appeared to die of sudden effusions of blood or serum in the lungs. It was an unexpected effusion of this kind which put an end to the life of Mrs. Keppele after she had exhibited hopeful signs of a recovery.
I saw one person who recovered from an affection of the lungs, by means of a copious expectoration of yellow phlegm and mucus. But the brain was principally affected with morbid congestion in this disease. It was indicated by the suffusion of blood in the face, by the redness of the eyes, by a dilatation of the pupils, by the pain in the head, by the hæmorrhages from the nose and ears, by the sickness or vomiting, and by an almost universal costive state of the bowels. I wish to impress the reader with these facts, for they formed one of the strongest indications for the use of the remedies which I adopted for the cure of this disease. It is difficult to determine the exact state of these viscera in every case of bilious and yellow fever. Inflammation certainly takes place in some cases, and internal hæmorrhages in others; but I believe the most frequent affection of these viscera consists in a certain morbid accumulation of blood in them, which has been happily called, by Dr. Clark, an engorgement or choaking of the blood-vessels. I believe further, with Dr. Clark[20] and Dr. Balfour[21], that death in most cases in bilious fevers is the effect of these morbid congestions, and wholly unconnected with an exhausted state of the system, or a supposed putrefaction in the fluids. It is true, the dissections of Dr. Physick and Dr. Cathrall (to be mentioned hereafter) discovered no morbid appearances in any of the viscera which have been mentioned, but it should be remembered, that these dissections were made early in the disease. Dr. Annan attended the dissection of a brain of a patient who died at Bush-hill some days afterwards, and observed the blood-vessels to be unusually turgid. In those cases where congestion only takes place, it is as easy to conceive that all morbid appearances in the brain may cease after death, as that the suffusion of blood in the face should disappear after the retreat of the blood from the extremities of the vessels, in the last moments of life. It is no new thing for morbid excitement of the brain to leave either slender, or no marks of disease after death. This, I have said, is often the case where it exceeds that degree of action which produces an effusion of red blood into serous vessels, or what is called inflammation[22]. Dr. Quin has given a dissection of the brain of a child that died with all the symptoms of hydrocephalus internus, and yet nothing was discovered in the brain but a slight turgescence of its blood-vessels. Dr. Girdlestone says, no injury appeared in the brains of those persons who died of the symptomatic apoplexy, which occurred in a spasmodic disease which he describes in the East-Indies; and Mr. Clark informs us, that the brain was in a natural state in every case of death from puerperile fever, notwithstanding it seemed to be affected in many cases soon after the attack of that disease[23].
I wish it to be remembered here, that the yellow fever, like all other diseases, is influenced by climate and season. The determination of the fluids is seldom the same in different years, and I am sure it varied with the weather in the disease which I am now describing. Dr. Jackson speaks of the head being most affected in the West-India fevers in dry situations. Dr. Hillary says, that there was an unusual determination of the blood towards the brain, after a hot and dry season, in the fevers of Barbadoes in the year 1753; and Dr. Ferriar, in his account of an epidemic jail fever in Manchester, in 1789, 1790, informs us, that as soon as frost set in, a delirium became a more frequent symptom of that disease, than it had been in more temperate weather.
III. The stomach and bowels were affected in many ways in this fever. The disease seldom appeared without nausea or vomiting. In some cases, they both occurred for several days or a week before they were accompanied by any fever. Sometimes a pain, known by the name of gastrodynia, ushered in the disease. The stomach was so extremely irritable as to reject drinks of every kind. Sometimes green or yellow bile was rejected on the first day of the disease by vomiting; but I much oftener saw it continue for two days without discharging any thing from the stomach, but the drinks which were taken by the patient. If the fever in any case came on without vomiting, or if it had been checked by remedies that were ineffectual to remove it altogether, it generally appeared, or returned, on the 4th or 5th day of the disease. I dreaded this symptom on those days, for although it was not always the forerunner of death, yet it generally rendered the recovery more difficult and tedious. In some cases the vomiting was more or less constant from the beginning to the end of the disease, whether it terminated in life or death.
The vomiting which came on about the 4th or 5th day, was accompanied with a burning pain in the region of the stomach. It produced great anxiety, and tossing of the body from one part of the bed to another. In some cases, this painful burning occurred before any vomiting had taken place. Drinks were now rejected from the stomach so suddenly, as often to be discharged over the hand that lifted them to the head of the patient. The contents of the stomach (to be mentioned hereafter) were sometimes thrown up with a convulsive motion, that propelled them in a stream to a great distance, and in some cases all over the clothes of the by-standers.