14 ° ffc Caujes and Cure Seizure, and their Energy of Operation. And this will not be difficult to conceive by thofe who are acquainted with that univerfal Pro- perty of Matter, whereby it is more or lefs determined to draw, and unite again, when ieparated into Parcels, according to the greater or leiTer Affinities of their Figures, Solidities, and Quantities of Motion. As nothing therefore in Nature is fuppofed to 'bear a greater Similitude, than in this Cafe the natural animal Salts do with what hath been fiibtilized and fet on Float in the Air, it can be no Wonder that when the Ambient is fated with the latter, they readily join with the former, as foon as they are received into the Body. And thi's is fupported by the Authority even of Belling who allows, in the Beginning of his XXVllhh Tropfition, that the Antecedents to a peftilential Fever do lometimes vitiate the Spirits immediately in Quality. AS the ordinary Courfe therefore of pro- ducing Fevers is by diibrdering the Blood firft in Quality, with inch Mixtures as coagulate, it, that is, as make it unequally fluid, fome Farts being thinner, and others thicker than natural fo. by thele extreamly fubtle Efflu- ^■a, in a Contagion, the Spirits are deftroyed in /
