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stone. 'Tis true, that the force of such Instances is indirect, and that they do not expresly prove the Hypothesis in whose favour they are alledged; but yet they may do it good service by disproving the Grounds and Conclusions of the Adversaries, and so (by removing Prejudices) making way for the better entertainment of the truth.
Secondly, we may sometimes obtain the same or the like Quality by Artificial and sometimes even temporary Compositions, which, being but factitious bodies, are by Learned Adversaries confess'd not to have Substantial Forms, and can indeed reasonably be presum'd to have but resulting Temperaments: As will be hereafter exemplifi'd in the production of Green by compounding Blew and Yellow, and in the Electrical Faculty of Glass; and in the temporary whiteness produc'd by beating clear Oyl and fair Water into an Ointment, and by beating water into a froth, and, more permanently, in making Coral white by flawing it with heat; and in divers other Particulars, that will more properly be elsewhere mention'd.
Thirdly then, in some cases the Quality propos'd may be either introduced, or vary'd, or destroy'd in an inanimate body, when no change appears to be made in the bo-dy,
