THE PREFACE.

TO Institute in this Age a new Doctrine of Fea∣vers, may perhaps seem the same thing, as if any one should go about to describe the midst of our Country, for a Land before unknown. For what respect the Diagnosis of this Di∣sease, seem to be firmly Established already, by the Precepts and Practice of the Antients and Moderns; yea by long Experience, they are so generally in the mouth, and known of all men, that nothing can be more. How∣ever I deserve pardon, if I a little receed from the Vulgar Opi∣nion concerning Feavers, as a way mightily worn out; and go in a less trodden Path; because I am not the first, or only man that directs his course against the received Opinion, as against a Stream. For in truth, in the Medical Art, (and that deservedly) those things have not pleased the men of our Age, which did those of the for∣mer: because the Antients relying on a false Position concerning the motion of the Blood, proceeding as it were through slippery and moist places, often fell foully and dangerously: wherefore it is no wonder, if those who come after should take care for the thorough instauration of Physick, and for the Re-Edifying the Building, (as they say) even from the ground, the Antient Props being fallen down, on that which our most Famous Harvy hath laid, the Circula∣tion of the Blood, as a new Foundation in Medicine. But in this Work, Learned men of other Countrys, but chiefly of our own, have happily laboured, not only in removing the Rubbish of the for∣mer Building, but for the supplying this plentifully with Stone, Planks, and other matter. In times past, among the Antients, as the distribution and Natural motion, of the Nutritious humor, of the Blood and Nervous juice; so the Feaverish heats, and pre∣ternatural motions of them, were wholly hidden and lay in the dark: but now new Lights have shined forth, and it is granted us to know the Causes of things before hidden, it doth not become pru∣dent men, and professing Philosophy, even to shut their Eyes and remain blind in the Light it self; but especially about a Disease Page  54 by which the third part of Mortals have still fallen to this day, to be rather willing to Err with the Antients, than to understand the Truth with the Moderns, or to believe what is more likely, argues a mind guilty of notable stubbornness. When therefore the Puretology or Feaver Tracts of former Medicine, had no firm and stable Basis, and that it is easie to shew that it was built upon very many, and plainly false Errors, what should hinder, but that we having gotten more certain Principles, should en∣deavour to erect a better Science concerning Feavers? Truly I think it would hardly be, altho the pleas of the Antients, should be yet openly maintained in the Schools, but that many Physiti∣ans, who have a mind to look within the Bark, would frame new Hypotheses to themselves from their own Ratiocination, by which they might more exactly quadrate the Phaenomena of Feavers, than by that of the Antients. But it may be objected, that Fea∣vers have been happily cured by the same Remedies, and the like method of Curing, from the times of Hippocrates and Galen, even to our days; and therefore it may seem a rash Work and little safe, that we should endeavour new things, after having had the Experience of so many Ages, especially since it is about the hu∣man Body. To this it will be easie to answer, that Medicine was at first Empirical, and Remedies were not invented by general Precepts, or by Rule, but by the frequent trial of several things: And if led by the Example of Hippocrates, his Followers had only polished his Observations and Experiments, without doubt the Medicinal Art had grown up better, more handsomly, and with greater benefit to the Sick. But that the Light, clearly inkind∣led by the Antients, did so suddenly shut up, and darkned the Eyes of Posterity, it was, the preposterous study of those, who too bastily framed, almost out of their own Brain, Physick into a general Method, after the manner of some Speculative Science: for by this means, before they had laid a firm Foundation, a sufficiently specious, and deceitful Pile of unstable Doctrine, was erected. That therefore in the Cure of Feavers, some Indications being more antiently received, remain yet confirmed, and are to be perpetually observed, is to be ascribed wholly to Experience, the first Mistress of this Art, and not to the Precepts of Scholars. And from hence, I hope for my self, to have gotten a defence sufficient enough; for if the Opinions wholly erronious of the Antients, had not hin∣dered, but that the practice of Medicine, at first instituted by a certain induction of observations; had proceeded commodiously enough; the Theory being joyned with Truth, would have brought much less hurt to the Sick; or have less carried away those exercising Medi∣cine, Page  55 quite contrary from that Path, which Antiquity had left com∣mended to us. In the mean time, 'tis not to be dissembled, that naked Experience, without the helps of Method and Reason avails little, yea very often doth much hurt; for neither are the same Disea∣ses, every where to be driven away by the same Remedies. But he seems to have hit the mark, who joyns both together, that Rea∣son may not pervert Experiments, and Nature it self, not that this may remove Reason from its place. Altho that I know well enough, I have not obtained it, yet I will freely profess, that I have aimed at this Mark; and perhaps I may have deserved some praise, even in failing in these sort of Adventures; for after I had not found in Books, what might satisfie a mind desirous of Truth, I resolved with my self, to search into living and breathing Ex∣amples: and therefore sitting oftentimes by the Sick, I was wont carefully to search out their Cases, to weigh all the symptoms, and to put them, with exact Diaries of the Diseases, into writing; then diligently to meditate on these, and to compare some with o∣thers; and then began to adapt general Notions from particular Events: and when by this means, for a long time, observing the Accidents and Courses of Feavers, I had busied my self, for the finding out forms of Reasons for their Cure, at length a new Pa∣thology of this Disease was conceived in my mind; which afterwards, by the frequent increasing Concourse of Observations, as it were the Juice and Blood, was formed by degrees into a Child, such as it now appears. But the Infant, which I had ordered to be kept closely, in our private house, being remarkable for Paradoxes, as it were a monstrous shape, the importune diligence of Friends has taken care to bring abroad being gotten forth of my hands, and to be pub∣lickly beheld. What therefore is there said concerning Feavers, be∣sides the common manner, I would not have any one esteem it brought forth by me, as from a Doctor in the Chair: doubting, I bring these thoughts into Public, and submit them to the Examination and E∣mendation of the more Learned. That others before me have not spoken all things truly concerning this thing, shall be an Argument that I may Err, yea (if you please) that I have Erred: however, if I should have rightly traced forth any marks, in this, at least new search of Truth; and shall have incited others (who are far better able) by this occasion, to the full finishing of it; it will not repent me altogether of this, tho rash beginning.