[Illustration: FIG. 5.--REHEATING FURNACE.]
_Trip Hammer_.--The workman at the hammer takes the bloom from the hands of the assistant and shingles it under the head. Then he begins to give it shape, bringing it to the state shown at c, in Fig. 7. The assistant then brings him another bloom and takes the one that has been shingled to the reheating furnace, where he heats but one of its extremities. When the four blooms have been shingled, the workman takes up the first and begins to draw out one of its extremities, which he afterward cools in water and uses as a handle for finishing the work, d. Then he reheats the other extremity, and, after drawing it out as he did the other, obtains a bar of finished iron which he doubles, as shown at e, to thus deliver to the trade.
[Illustration: FIG. 6.--CADINHE IN OPERATION.]
One of these bars weighs from 11 to 12 kilogrammes. It will be seen that, during the course of the work, the furnace workmen and the hammer workmen have well defined duties to perform; but it is not the same with the assistant, who goes from one to the other according to requirements. There are, however, some forges in which each of the workmen has an assistant, since the blooms produced are heavier, and one assistant would not suffice for the work of the two men. In such a case the assistant at the crucibles carries the blooms to the reheating furnace, and the assistant at the hammer carries them from thence to the hammer.
[Illustration: FIG. 7.--WORKING THE BLOOM.]
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.