Seâ:. 4.

Of Fermentation.

they difplace the Wuter, and forceit but of their Interftices, till theOil is diluted every where alike,and then the Fermentation ceaiès.But if the Salts are Elaßic, which isvery probable, iince there is icarceany Body entirely void of Elaßicity,they will not only ruih upon oneanother with violence, but recoilafter the Shock, and move in a con-trary Direction : from hence pro-ceeds that reciprocal Fluctuation oíParts, which we obierve every way,and at length an Efervefccncy . Andihus this kind of Fermentation, u-iually afcrib'd to an imaginary An-tipathy between Acid and Alcali,may mechanically enough be ac-counted for.

That this Fermentation is raifedby Elaßic Particles, is very proba-ble, becaufe all Bodies ferment moreilowly when iêcluded from the Air,which all allow to be Elaßic. Nordoes that considerable Jiarifaclion,ib remarkable in Fermentation, alittle favour this Opinion; for noBodies can be rarify'd to that de-gree, unlefs they have fome Air in-cluded in them, as is generally thecaiè of all Fluids whatever. But noArgument can make more for us,than that which may be taken fromSteel; for it is notorious, that Steelis \ery Elaßic: it is for this Rcaibn,very probably, that an Ejfervefcencefollows upon mixing it with Oil ofVitriol; but yet if you add Waterto this Mixture, it will cauiè a moreviolent Heat, and fo diflblve theiron fooner. Spirit of Vitriol, whichhas a large Proportion of Water, ifmix'd with the Oil, does the famething ; the reafon of which Ap-pearance feems to be this, That inOil of Vitriol, when it is weil freedfrom Phlegm, the Salts are ib con-dens'd and compact, that they maybe faid to lie and reft upon the

19

Iron s and ib being almoif. withoutMotion, cannot make any coniide-rable Impreffion upon it : but uponthe pouring on of Water, they arenot only more broken and ièpara-ted into Idler Corpulcies, by whichmeans they attack the Iron with agreater Velocity, but likewifè theyare more attracted by the Particlesof the Iron, than by one another,which increalcs the interline Mo-tion. Upon this consideration, forthe better performing the Solution,it is cuftomary to weaken the Men-ßruttm ; for Aaua Fortis duplexdoes not diflblve Silver ib well, asthat which has more Phlegm in it:and fometimes Spirit of Wine, thehigher rectify'd it is, the more it isunfit for extracting Tincfttres. Inlike manner, Braß, Mercury, andmany other Bodies mix'd with Oilof Vitriol, will icarce caufe anyFermentation, but will ferment andfroth very much, when mix'd withSpirit of Nitre, which is a muchlower Menßmum. On the con-trary, if too much Phlegm be ad-ded, it will entirely check the Fer*mentation; for this reafon, Spiritof Vitriol, if it be weak, railes noEffer-vefcence with Iron : and thefame thing happens too ;n the Ex-periment of Oil of Vitriol, if youpour too much Water upon it; forthe Menflruum being thus diluted,the Particles of Salt are ieparated,and removed from ou» another lbfar, as to be out oí each other'sSphere of AttraBion. So that inthis Operation, both an Elaßic andznAttracihe Force areneceifary Af-filiants; and all that Variety we icein Fermentation, is owing to the dif-ferent degrees of them.

Hence it isj that oftentimes new

Bodies ariiè upon Fermentation, their

former Texture being entirely alrer'd

and chang'd by the continuai Col-

C í liiion