We have seen that the workman who has charge of the fire contents
himself with putting charcoal and ore alternately into the crucibles,
and that too according to the aspect of the flames, without making any
examination in the interior, in order to judge whether the work is
proceeding well. The bloom forms gradually beneath the nozzle of the
tuyere, in the center of the bed of sand and charcoal, and is surrounded
on every side with an exceedingly pasty mass, formed of silicates of
iron and manganese (Fig. 7). It is only at the end of the operation that
the workman, by means of a rod, causes the burning coal to drop and
verifies the proper position of the bloom by breaking the layer of
scoriæ that surrounds it. This coating he breaks off, removes the bloom
with a hook, and agglutinates with his rod the different bubbles that it
exhibits, and the assistant then carries it to the hammer.