AS to the spreading of a Contagion from one to another, and so on to Thousands, there is nothing can be possibly more swift in the Progress of Fire; and it exceeds even Antimony in the Retention of its Properties, though that loses them not in a thousand Infusions: But the instantaneous Progress of this Enemy to Mankind is best illustrated by the Rapidity of Light, which is not greater. But more of this we pass by till we come professedly to speak of a Contagion.
SECONDLY, the particular Nature of the pestilential Miasmata, may be known from their peculiar Influence upon the saline Particles in a humane Body; for nothing acts with more Efficacy and Energy upon a saline Body, than another partaking of the same Quality; and nothing is more plain than that this nitrous Spirit is of more Efficacy than the Alkahest it self, as by it the fibrous Parts of the Blood are immediately corroded and dissolved; and therefore after dangerous Hemorrhages, very little Coagulation can be obtained in the extravasated Blood, unless by its being exposed to the Cold: but as often
as that does happen, do not we immediately find a Fixation of the Fluids, and a certain Congelation of the Juices, which greatly retards their rapid Motions, and sometimes brings even a total Stagnation: It’s furthermore of considerable Importance to our present Argument, that Spasms, the constant Attendants of a Plague, have their Origin from an acrid vellicating Salt in the nervous Fluid.
TO these it may likewise be added, that a Pestilence has a great Similitude to a scorbutick Habit, having its Origin from a saline Constitution of Blood; and the great Likeness there is in many Circumstances of their Generation and Propagation, insomuch that after a Pestilence is with others ceased, it will yet continue to infect scorbutick Constitutions; as hereafter will further appear: From the same Cause likewise does a pestilential Contagion reign most in Maritime Countries, and near the Sea-Coasts; because such a saline Disposition does there most abound; and the Truth of this, the Maritime Parts of our own Country do by sad Experience too much testifie.
LASTLY, If Arguments taken to this Purpose from the Method of Cure were valid, from thence it may be gathered, that a saline Spirit hath a great share in giving Rise to a Pestilence; for in our curative Regards for this Distemper, a skilful and upright Physician bends his whole Care at first to prevent its Attack, which he does by the Use of oleaginous Substances, by that Means expecting to cover over the Stomach as it were with a Plaster, to guard it against sharp and corrosive Effluvia; the same Intention is also pursued by Medicines, in endeavouring to defend against the poysonous Taint, or throw it out when received by Alexipharmicks and Diaphoreticks: For every one who is but tolerably conversant in such Practice, very well knows that the saline Particles are thrown off this Way much more effectually than by any other; and a further Demonstration of this Matter is also, that the Sweat of infected Persons, as in the late Sickness, gives extream pungent Pains by its Acrimony in its Exit; and that the more brackish such Sweat comes out, the more serviceable it proves; whereas when it happened to be
soft and insipid, it was a sure Forerunner of worse Symptoms, and even of Death.
FURTHERMORE, as to curative Intentions, all Diligence was used to preserve and restore the internal Ferments from a Contagion; and this was chiefly done by saline Preparations of various Kinds, which gave greater Energy to the natural Spirits, so as to alter and renew them by Means of that Similitude of Texture and Constitution naturally between them.
AGAIN, what was excreted did greatly establish this our Hypothesis; what was thrown up by hard Vomiting discovered nothing more than a rancid Brackishness, that vellicated the Stomach into Convulsions by its acrimonious and corrosive Qualities; and the frothy and fermentative Nature of what was ejected by Stool, fully showed its saline Mixture: But we shall come more fully to talk of this hereafter: To conclude therefore this Controversie; although the Hypothesis here laid down may at first Appearance seem new, yet it does not so far differ from the Sentiments of the Ancients upon the same Subject, as confirm
and explain what they have said: It comes down to us for the Opinion of some of them, that a Putrefaction of Choler in an humane Body gives Rise to a Pestilence; and of others, that Fire may be so corrupted, as to occasion the same; what therefore the former conceived of Choler, and the latter of Fire, we judge more justly ascribed here to a vitiated saline Spirit. But least we should too long dwell upon this Argument, if it was needful to recite all the Causes enumerated by Authors of this Malady, it would be difficult to find any one which does not coincide with this our Hypothesis; so that whosoever pleases to be at this Pains, must either assent with us, or reject them; and he that does not like our Opinion, would do well to shew a better.
IN the above-described Pestilence, as indeed in many others, Persons frequently died, without any preceeding Symptoms of Horror, Thirst, or concomitant Fever: For the Confirmation of which, I shall give an Instance or two out of a great many; A Woman, who was the only one left alive of the Family, and yet to her Thinking perfectly well, perceived upon her Breast