Doctrine of &ualttte#* 3 l 



Principle. And yet I have met with 

 many inftances, wherein Qualities are 

 produced,or aboliftied, or very much 

 altered, without any manifeft intro- 

 duction , expulfion, or confiderable 

 change of the Principle whereon 

 f^* Quality is faid to depend, or per- 

 haps of either of the two others : 

 As when a piece of fine filver 5 that 

 having been neald in the fire, and fuf- 

 fer'd to cool leifurely^is very flexible, 

 is made ftiff and hard to bend, barely 

 by a few ftroaks of a hammer. And 

 a firing of a Lute acquires or lofes a 

 fympathy, as they call it r with another 

 (fring of the fame or another Inftru* 

 ment, barely by being either ftretch* 

 ed fo as to make an Unifon with it, 

 or fcrewd up or let down beyond 

 or beneath that degree of Ten- 

 (ion. 



To multiply inftances of this kind 

 would be to anticipate thofe^you will 

 hereafter meet with in their due pla- 

 gcs. And therefore I (hall pafs on 

 from the firft fort of Ph<£nomena> that 

 favour not the Chymical Hypothefis 



about 



