Stock Photo: Overshot water wheel turning the cam-shaft of a stamping mill being used to turn the crush ore to begin the process of extracting metal from the ore won from a mine. From De re metallica, by Agricola, pseudonym of Georg Bauer (Basle, 1556). Woodcut

Stock Photo: 1746-1918 Overshot water wheel turning the cam-shaft of a stamping mill  being used to turn the crush ore to begin the process of extracting metal from the ore won from a mine.  From De re metallica, by Agricola, pseudonym of Georg Bauer (Basle, 1556).  Woodcut