Metallographia, or, An history of metals [microform] : wherein is declared the signs of ores and minerals both before and after digging, the causes and manner of their generations, their kinds, sorts, and differences : with the description of sundry new metals or semi metals, and many other things pertaining to mineral knowledge : as also the handling and shewing of their vegetability, and the discussion of the most difficult questions belonging to mystical chymistry, as of the philosophers gold, their mercury, the liquor alkahest, aurum potabile, and such like : gathered forth of the most approved authors that have written in Greek, Latine, or High-Dutch, with some observations and discoveries of the author himself / by John Webster ...