208 PHYSIOLOGICAL REMAINS. 



but transitory, and a kind of toy or pleasure, yet there 

 is a more serious use of it ; for that it discovereth 

 the delicate motions of spirits, when they put forth 

 and cannot get forth, like unto that which is in vege 

 tables. 



For induration, or mollification ; it is to be in 

 quired what will make metals harder and harder, and 

 what will make them softer and softer. And this 

 inquiry tendeth to two ends : first, for use ; as to 

 make iron soft by the fire makes it malleable. Se 

 condly, because induration is a degree towards fixa 

 tion, and mollification towards volatility ; and there 

 fore the inquiry of them will give light towards the 

 other. 



For tough and brittle, they are much of the same 

 kind, but yet worthy of an inquiry apart, especially 

 to join hardness with toughness, as making glass 

 malleable, etc. and making blades strong to resist and 

 pierce, and yet not easy to break. 



For volatility and fixation. It is a principal 

 branch to be inquired : the utmost degree of fixation 

 is that whereon no fire will work, nor strong water 

 joined with fire, if there be any such fixation possible g 

 The next is, when fire simply will not work without 

 strong waters. The next is by the test. The next 

 is when it will endure fire not blown, or such a 

 strength of fire. The next is when it will not endure, 

 but yet is malleable. The next is when it is not 

 malleable, but yet is not fluent, but stupified. So of 

 volatility, the utmost degree is when it will fly away 

 without returning. The next is when it will fly up, 



