Dr. Willis's practice of physick being the whole works of that renowned and famous physician wherein most of the diseases belonging to the body of man are treated of, with excellent methods and receipts for the cure of the same : fitted to the meanest capacity by an index for the explaining of all the hard and unusual words and terms of art derived from the Greek, Latine, or other languages for the benefit of the English reader : with forty copper plates.

THE PREFACE TO THE Treatise of Feavers.

To the Friendly Reader,

TO Institute in this Age a new Doctrine of Feavers, 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 Disease, 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. However I deserve pardon, if I a little receed from the Vulgar Opinion concerning Feavers, as a way mightily worn out; and go on in a lesstrod∣den Path; because I am not the first, or only Man that directs his course against the re∣ceived Opinion, as against a Stream. For in truth, in the Medical Art, (and that de∣servedly) those things have not pleased the Men of our Age, which did those of the former: because the Antients relying on a false Position concerning the Motion of the Blood, pro∣ceeding a•…•… 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 Circulation 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 former Building, but for the supplying this plen∣fully 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 Ner∣vous Juice; so the Feaverish Heats, and Preternatural Motions of them, were wholly hidden and lay in the dark: but now new Lights have s•…•…ined forth, and it is granted u•…•… to know the Causes of things before hidden, it doth not become prudent Men, and pro∣fessing Philosophy, even to shut their Eyes and remain blind in the Light it self; but especially about a Disease 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 endeavour to erect a better Science coucerning 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 Physicians, 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 ob∣jected, that Feavers 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 Human

Body. To this it will be easie to answer, that Medicine was at first Empirical, and Reme∣dies 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 inkindled by the Antients, did so suddenly shut up, and darkned the Eyes of Posterity, it was, the preposte∣rous study of those, who too hastily 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 Doctrin, was erected. That therefore in the Cure of Feavers, some Indications being more antiently re∣ceived, 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 •…•…ence, I hope for my self, to have gotten a defence sufficient enough; for if the Opinions wholly erroneous of the Antients, had not hindered, 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 Medicine, quite contrary from that Path, which Antiquity had left commended 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 Diseases, every where to be driven away by the same Remedies. But he seem•…•… to have hit the mark, who joyns both together, that Reason may not pervert Experi∣ments, 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 thi•…•… Mark; and perhaps I may have deserved some praise, even in failing in these sort of Ad∣ventures; 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 Examples: and therefore sitting oftentimes by the Sick, I was wont carefully to search out their Cases, to weigh all the Sym∣ptoms, and to put them, with exact Diaries of the Diseases, into Writing; then diligently to meditate on these, and to compare some with others; 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 Pathology of this Disease was conceived in my mind; which afterwards, by the frequent increasing Concourse of Observations, a•…•… 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 publickly beheld. What therefore is there said concerning Feavers, besides the common manner, I would not have any one esteem it brought forth by me, as fr•…•…m a Doctor in the Chair: doubting, I bring these thoughts into Publick, and submit them to the Examination and Emendation 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 •…•…raced 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.