mineral found in Derbyshire, and used by mechanics for all sorts of finer grinding and polishing, and sometimes for cutting stones. According to Ferber, it is a tripoli mixed with calcareous earth.
Rottenness. See Putrefaction.
mineral found in Derbyshire, and used by mechanics for all sorts of finer grinding and polishing, and sometimes for cutting stones. According to Ferber, it is a tripoli mixed with calcareous earth.
Rottenness. See Putrefaction.