35 
Copper. 
to introduce the Trial Iron into the metal exposed at the 
nose of the blast. The metafbeing perfectly melted, the 
blast should be continued, with fresh coals for half an 
hour : the copper being less oxydable than the metals 
mixed with it, these rise in scoriae to the top, and are re- 
moved occasionally by the refiner, by raising them with 
pointed sticks, and then raking them off as quickly as 
possible lest the metal should cool, first removing the hot 
coals all round and stopping the blast : the surface is a- 
gain covered with hot coals, and the blast renewed. When 
the surface affords no more scoriae, the refiner tries the 
metal with the iron which is a rod of about 3 feet 6 inches 
long, about as thick as a finger, and pointed with polished 
steel. This is heated moderately, and plunged quickly into 
the melted metal of which a part sticks to the iron. If it 
removes easily from the iron, and is of a good colour and 
all smoke is over, the fire is continued enough. If it 
sticks too hard to the iron, the metal is not yet pure. 
If pure, the surface of the copper is sprinkled (not 
splashed) with water, and the congealed plates are taken 
off* with pinchers, and is the rose copper, or Rosette. 
As the blast strikes the copper, care should be taken 
that it does not blow away the coals, which also may now 
and then be sprinkled to prevent their flying off*. Care also 
should be taken to keep the mouth of the bellows clean,* 
and the sides of the basin should be so managed that the 
inclination of the melted matter should be slightly toward 
the bellows or tweer. 
If there should not be metal enough to fill the basin so 
that the blast shall strike on the melted metal, a charge of 
copper already refined should be put in, or the ’whole 
mass may be stirred upward, with a stick of wood, which 
when burnt away may be supplied by another. 
When the Rosettes are taken off* by the pinchers, they 
should be plunged into water obliquely by the edges, not 
