The London practice of physick, or, The whole practical part of Physick contained in the works of Dr. Willis faithfully made English, and printed together for the publick good.

CHAP. VII. Of continual Fevers.

AContinual Fever is that whereof the access is prolonged to many dayes without any cessation: it has its times of remission and exacerbation, but none of intermission; the burning some∣times is more remiss, sometimes more intense, but the Diseased are still in a Fever, till the Disease be wholly solv'd by a Crisis, or an in∣sensible recovery.

Now there are three degrees or manners of Effervescency by which the Species of continual Fevers are determined: from the subtle por∣tion of the boyling Blood, or from the Ebullition of the Spirits arises the Ephemera, also the Synocus of one or many dayes: from the sulphu∣reous or oily part of the Blood too much heated and kindled, is rai∣sed the putrid Fever; thirdly, on a venemous Miasm infecting the Blood, and congealing its Liquour, malignant Fevers depend: in each of these, from the depravation or rather corruption of the nutritive Juice, fresh heapt together in the Blood, various Paroxisms, Inequalities, and critical Motions arise.

If it be askt after what manner the Effervescency of the Blood in a continual Fever differs from that other which makes intermittents; I say, that the Effervescence of the Blood in the latter depends only on the mingling of some fermentative Matter with the Blood, which will not duely mix with it, and on its heaping together to a plenitude of Tur∣gescency: by reason of the Effervescency of this with the Blood in the Vessels, and its deflagration in the Heart, the fit is caused, its difflation is followed by an Apyrexia, so that in the intervals of the fits neither the Spirits nor the Sulphur make an effort, but the Liquour circulates evenly and without tumult in the Vessels, the bond of mixture being entirely preserved; on the contrary, in a continual Fever, the Disor∣ders of the Spirit or Sulphur, or of both of them together cause the ebulli∣tion of the Blood by their proper Effervescence, without the mixture of another thing: Wherefore, for a cessation of the hurning heat, besides the difflation of the excrementitious matter, a deflagration of the kindled Blood, and its reduction to a due Crasis, are required.

The Constitution of the Blood in a continual Fever, is as that of Wines when they ferment by too rich Lees; that is to say, they are strong with Spirit, and grow turgid with an exalted Sulphur, and therefore of their own accord without the mixture of another thing, they fall into a heat and boyl violently: In an intermittent Fever the Blood is stirr'd

after such a Manner as Wines when they fall a fermenting by reason of something which is not missible being put into them: Moreover, in this Fever the Disposition of the Blood is like that of Wines, when in their declining state they become over fretted, ropy, or also sour; in which the Spirit is deprest, while the Salt or Sulphur, or both together, are above the rest, and affect the whole Liquour with their disorder: an intermittent Fever for the most part is without danger, because the parts that compose the Blood, tho they have changed a little their Crasis, however keep their bond of mixture; and whilst they are at liberty, circulate evenly in the Vessels; and pervert the nutritive Juice into a matter not altogether preternatural, but rather infesting with its Plenitude and Turgescency. In a continual Fever, besides the dis∣temperature, the mixture of the Blood, and the texture of the Liquor are somewhat dissolv'd, that its corruption easily follows, wherefore this Disease is often terminated in death; and the nutritive Juyce is depraved to a matter wholly vitious, and altogether offensive to Na∣ture.