The predisposing and occasional causes of nervous and putrid fevers are, many or perhaps all of the preceding causes: noxious miasma or contagion, engendered from human effluvia in cities, jails, hospitals, dirty, small, crowded houses and apartments, especially in unventilated alleys and lanes; accumulation of corporeal filth from want of cloathing, change of raiment, slothfulness; contagion concentrated in porous materials, furniture, raiment, and houses: cadaverous exhalations, effluvia from putrid carcasses of animals, and from both animal and vegetable heaps in a state of fermentative putrefaction: damp rainy seasons: bad harvest, and putrid grain; putrid diet animal or farinaceous: improper medical treatment of remittent fevers; corrupted bile, or other secerned and excreted fluids, noxious in quantity or quality: profuse evacuation, immoderate venery, desponding passions of mind, intemperance in food or drink, stoppage of perspiration, &c. Of miliary fever the causes are, estuation, hot regimen, and rooms, during fever or parturition, excessive evacuations, weak constitutions, debility, depressing passions, moist air, wet summer.
The predisposing and occasional causes of inflammatory fevers and diary are, cold climate and winter: cold winds: change of seasons: heat of the atmosphere: insolation: excessive labour, exercise, and fatigue: violent passions of mind: long watching: cold drink when the body is heated: intoxication with spirituous liquors: crude chyle: heating stimulating diet: disordered stomach, plethora: excess of coagulable lymph and its tenacity: menstrual, lacteal, hæmorrhoidal, arthritick: warm baths; excruciating pain.
The predisposing and occasional causes of small pox, measles, scarlet fever, and sweating sickness, are unknown, both as to their source and nature: the two first are exotick leavens. Of plague: venomous effluvia in certain hot climates, from putrid animal exhalations and filth, such as the stagnant canals and reservoirs of putridity in the city of Grand Cairo: putrid emanations from swarms of dead locusts. Predisposing causes to pestilential infection are, long watching, hunger, poor diet, intemperance, excess of venery, fatigue, terror, fear, debility, low spirits, &c.
With respect to the great sources of fevers, noxious miasma from morasses, contagion from human effluvia, and animal bodies, and that from specifick unknown origin, I shall make a few observations. Of what elementary nature miasma and contagion consist; the analysis of their minute atoms; whether animalculæ, or to us invisible emanations, I pretend not to decide. Of small pox, measles, scarlet fever, and sweating sickness, we are totally ignorant of their origin and essence. We, however, know to a certainty, and it is of infinitely more importance to the publick safety, that neither marshy miasma, nor those from human effluvia, spread to any considerable distance through the air. Even by the plague the atmosphere is tainted to a very inconsiderable distance; and mankind find an asylum and sanctuary within a few yards. Nor do marshy miasma emitted from the earth, mount or diffuse themselves to any considerable distance in the air: the inhabitants at the top of a hill have continued healthy, whilst those situated in a swamp at the bottom, have been infested with intermittents, and remittents. To what distance the contagion of small pox, measles, and scarlet fever extend through the air, I am ignorant: like the plague, the two former have been transplanted to distant regions, in animal bodies, or in polluted porous materials. Another important discovery of modern times is, that by fire and smoke, the heat of a baker’s oven, the most virulent contagion may be annihilated, when concentrated in apparel, spungy materials, ships, houses, &c.
Of Febrile Prognosticks.
The event of all the preceding fevers (intermittent excepted) is terminated with precipitancy in a few days, or, at the utmost, a few weeks in recovery, in death, or in some other disease. The predictions in fevers, and indeed in all diseases, should be deduced from the comparative mortality at different ages; the comparative mortality by different fevers; the symptoms peculiar to each genus, whether ominous or propitious; and the general symptoms applicable to an intire group or class. These enrich medicine with a rudder, compass and quadrant: in them consist the tactick and the sublime of medical divination. We have already treated of the three former, and have now only to add the general febrile predictions.
It is foreign to my plan, to squander time or words, in eulogy or censure of those elaborate treatises on the pulse and urine, and their presumed extensive application to the diagnostick and prognostick of diseases. Of strength and weakness, hardness and softness, fulness and inanition, slowness, celerity, velocity, saliency, intermission, irregularity, and a few other distinctions of the circulation and arterial pulsation, we are competent judges; and of the measurement of velocity to a still greater nicety with the stop-watch. But, with all due reverence to Galen and his copyists, down to De Bordeu, in discriminating the multitude and variety, if I may be permitted the expression, of complicated tones, combinations, divisions, subdivisions, chromaticks and chords in the arterial vibrations, we confess the bluntness and incapacity of our tangible organs. We have still fewer scruples to disclaim that affected sagacity and alchymistical intuition, of forming auguries from the urine; from its innumerable shades, intermixtures, pellicles, precipitation, and sediment. This is, even in our time, one of the decoys in vaticination to inveigle the ignorant and credulous; the stale manœuvres and chiromancy of vagabond empiricism and imposture.
A few words will finish our general remarks on the pulse. From physiology, we know that the whole mass of blood is circulated round the body from the heart, its lever and center, to the circumference, and back again, in the space of a few minutes. But in the velocity of the crimson torrent and arterial pulsation, prodigious variations ensue from age, sex, constitution, peculiar temperament, climate, season, food, drink, mental passions, exercise, rest, sleep, waking, health, different diseases, and different periods of the day. It is therefore, singly, a precarious sign; and did time permit, there would be no difficulty in demonstrating the urine to be infinitely more fallible. From infancy to old age, the velocity of the blood decreases, and is one half slower: in the adult and middle age, between sixty and eighty pulsations every minute is the usual natural pace: the febrile pulse is marked at 96, and is sometimes spurred to 130 or 140; and in infants sometimes outstrips the divisions of time or accurate mensuration.
All fevers with dangerous symptoms may be termed malignant; but in general, this term is appropriated to fevers, intermittent, remittent, nervous, putrid, exanthematous, and also to some of those complicated with topical inflammation. General prognosticks of danger are indicated by a concatenation of few or many of the following symptoms, which may, in some degree, be transposed to the intire febrile class; and to the phlogistick order not yet surveyed: as the brain, lungs, abdominal viscera, and organs indispensible to life, much deranged: debility in the executive and legislative functions; or vital, natural, and animal: signs of putrefactions.