406 PHYSIOLOGICAL REMAINS. 



most degree is when it will fly away without return- 

 ing. The next is when it will fly up, but with ease 

 return. The next is when it will fly upwards over the 

 helm 3 by a kind of exsufflation without vapouring. 

 The next is when it will melt though not rise. The 

 next is when it will soften though not melt. Of all 

 these diligent inquiry is to be made in several metals, 

 especially of the more extreme degrees. 



For transmutation or version. If it be real and true, 

 it is the farthest part of art, and would be well distin- 

 guished from extraction, from restitution, and from adul- 

 teration. I hear much of turning iron into copper ; I 

 hear also of the growth of lead in weight, which can- 

 not be without a conversion of some body into lead : 

 but whatsoever is of this kind, and well expressed, is 

 diligently to be enquired and set down. 



Dr. MevereTs answers to the foregoing questions, concerning 

 the variation of metals and minerals. 



1. For tinctures, there are none that I know, but that 

 rich variety which springs from mixture of metals with met- 

 als, or imperfect minerals. 



2. The imperfect metals are subject to rust, all of them 

 except mercury, which is made into vermilion by solution, or 

 calcination. The rest are rusted by any salt, sour, or acid 

 water. Lead into a white body called cerussa. Iron into a 

 pale red called ferrugo. Copper is turned into green, named 

 aerugo, ces viride. Tin into white : but this is 'not in use, 

 neither hath it obtained a name. 



The Scriptures mention the rust of gold, but that is in re- 

 gard of the allay. 



3. Calcination. All metals may be calcined by strong 

 waters, or by admixtion of salt, sulphur, and mercury. The 



1 So orig. Rawley translates it supra caput ; and it is probably a mis- 

 take for head. 



