An Account of Book

know, whether an Object glass be good or not, onely by looking upon it, without trying. This would be of good use, especially if it should extend so far as to discerne the goodness of such a glass, whilst it is yet on the Cement. An Account Of Dr. Sydenham's Book, entitled, Methodus Curandi Febres, Propriis observationibus superstructa. This Book undertakes to deliver a more certain and more genuine Method of curing Fevers and Agues, than has obtained hitherto: And it being premised, First, that a Fever is Natures Engine, she brings into the field, to remove her enemy; or her handmaid, either for evacuating the impurities of the blood, or for reducing it into a New State: Secondly, that the true and genuine cure of this sickness consists in such a tempering of the Commotion of the Blood, that it may neither exceed, nor be too languide: This, I say, being premised by the Author, he informs the Reader: In the First Section, of the different Method, to be employed in the cure of Fevers, not only in respect of the differing constitutions and ages of the patients, but also in regard of the differing seasons of one and the same year, and of the difference of one year from another. As to the Former, he shews, in what sorts of Patients, and at what time of the Fever, Phlebotomy, or Vomiting, or both, are to be used; and when and where not: In what space of time the Depuration if nature be not disturbed or hindered in her work, will be perform'd: When Purgatives are to be administred: How that Diarrhea's happen, if the Patient had in the beginning ning of the Fever an inclination to vomit, but no vomit was given; and that those symptoms, which commonly are imputed to a malignity, do, for the most part, proceed from the Relaxation of the tone of the Blood, caused by Medicines too refrigerating, or by the unseasonable use of Glisters in the declination of the disease. As to the Latter, he observes, that one of the chief causes, rendering the Cure of Fevers so uncertain and unsuccesfull, is, that Practitioners do accommodate their observations, they take from the successful cure of some Fevers in one season of the year, or in some one year, to that of all Fevers in any season, or in any year whatsoever. And here he observes, first, how vigorous the blood is in the Spring, and how dispirited in Autumn; and thence regulates the letting of blood, and Vomiting, and the giving of Glisters. Next, how difficult it is, to assign the cause of the difference between the Fevers of several years; and to prognosticate of the salubrity or insalubrity of the following part of the year: where yet he insinuates, that, when Insects do swarm extraordinarily, and when Fevers and Agues (especially Quartans) appear very early, as about Midsummer, then Autumn commonly proves very sickly. Lastly, what method and Cautions are to be used in the Cure of Epidemical Fevers. In the Second Section, he treats of the Symptoms, accompanying Continued Fevers; as Phrenses, Pleurises, Coughs, Hicoughs, Fluxes, &c. Shewing, both whence they are caused, and how they are to be cured: Where having inserted a considerable Paragraph, touching a certain Symptomatical Fever in the Spring, to be cured like Plurisics; he mentions among many Observables, this, as a chief one, that Laudanum, or any other Narcotick given against the Phrensy, in the beginning, progress, or height of a Fever, does rather hurt, than good, but in the declination thereof, is used with good success. To all which he subjoins a particular ac- compt of the *Iliac Passion* (esteem'd by him to be sometimes a *Symptome* also of Feavers;) not only discoursing of its cause (a preposterous inversion of the Intestins, proceeding either from Obstruction, or Irritation,) but adding also a very plain way of Curing the same; and that not by the use of *Quick-silver* or *Bullets* (by him judged to be frequently noxious) but only by *Mint water*; and the application of a Whelp to the Patients Stomach; to strengthen the same, and to reduce it again to its natural motion. In the *Third Section*, he treats of *Intermittent* Feavers, or of *Agues*: Where he discourses of the times of the *Cold* and *Hot* fits, and of that of the *Separation* of the subdued aguish matter: Finds difficulty in giving a satisfactory accompt of the *return of Fits*: distinguishes Agues into *Vernal* and *Autumnal*: Takes notice, that as there are few *Continued* Feavers, so generally there are only *Quotidians* and *Tertians*, in the *Spring*; and only *Tertians* and *Quartans* in *Autumn*; Of which having offered Reasons, that seem considerable, he proceeds to his Method of curing them; and, laying much weight upon the said difference, he prescribes and urges different ways to be used in that cure: Interserting among other things these notes; *First*, that the Period of Fermentation in Feavers, both *Continued* and *Intermittent*, is (if left to Natures own conduct, and well regulated, if need be, by Art) perform'd in about 336 hours or 14 days; subduing in *Intermittent* ones, the hours of intermission, and counting $5\frac{1}{2}$ hours for every Paroxism; and imputing the excursion beyond that time to the disturbance given to nature by the error of Practitioners. *Secondly*, that whoever hath had a *Quartan* formerly, though many years be pass'd, shall, if he chance to have another, be soon freed from it; and that a Physician knowing that may confidently predict this. In the Fourth Section, the Author, in conformity to the Custom of those that write of Fevers, discourses of the Small-pox; and First, examining the cause of this sickness and its universality, delivers his peculiar opinion of the blood's endeavouring a Renovation or a New Texture (once at least in a Man's life) and is inclin'd to preferr the same to the received doctrine of its malignity. Then, having laid down, for a foundation of the Cure, the two times, of Separation and Expulsion, he argues as well against too high an Ebullition or too hasty a separation (by a hot diet or high Cordials) as against too languid a one (by Blood-ting, Purges, and Cooling medicines.) The like he does to the Time of Expulsion, forbidding both immoderate Heat (whereby Nature's expelling operation is disturbed by a precipitated and too thick a crowd of the protruded pustules,) and too much Cooling, whereby due Expulsion is hindred. In short, he advises, to permit Nature to do her own work, requiring nothing of the Physician, but to regulate her, when she is exorbitant, and to fortifie her, when she is too weak. He concludes all, with delivering a Model of the Method, he would use for his own only Son, if he should fall into this Sickness. Advertisement. Whereas 'tis taken notice of, that several persons persuade themselves, that these Philosophical Transactions are publish't by the Royal Society, notwithstanding many circumstances, to be met with in the already publish't ones, that