The surface of the crucible 10 is covered by a housing 18 into which {HEAD ~ a reducing gas} is introduced at {TAIL ~ an inlet} 19 so as to flow generally contrary to the flow of metal in the crucible 10 which will thus be exposed to the reducing action of the gas 
is introduced at
The surface of the crucible 10 is covered by a housing 18 into which { HEAD ~ a reducing gas } is introduced at { TAIL ~ an inlet } 19 so as to flow generally contrary to the flow of metal in the crucible 10 which will thus be exposed to the reducing action of the gas
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH