4o ©f t&e Wttpmiml tojisine 



■ 



SECT. It 



Of the Mechanicall Qri- 

 gine or VrodnBion of 

 HEAT. 



AFter having difpatched the In- 

 ftances I had to offer of the 

 Produ&ion of Cold , it remains that 

 I alfo propofe fome Experiments of 

 Heat , which Quality will appear the 

 more likely to be Mechanically pro- 

 ducible , if we coofider the nature 

 of it, which feems to confift mainly, 

 ifnotonely, in that Mechanical af- 

 fe&ion of matter we call Local mo- 

 tion mechanically modified, which 

 modification, as far as I have obfer- 

 ved* is made up of three Conditi- 

 ons. 



The firffc of thefe is, that the agi- 

 nation of the parts be vehement* by 

 which degree or rapidnefs, the mo- 

 tion proper to bodies that are hot 



diftin- 



