Flattened Weld Area
This section shows an amorphous area of wavy metal – a stark contrast to the flat regular shapes of the steel sheets seen elsewhere. It might be supposed that the surface of such an irregular section would be bumpy, like the areas of messy weld. However the surface of this section is flat. The surface has not been cut or sanded down. Therefore the area must have formed against another surface, making the flat section as the molten metal cooled.
One explanation for how this area might have formed is that it is the remains from the floor underneath a welders table. As this welder worked (perhaps César, perhaps someone else) small bits of molten weld would fall off the piece they were working on and drop to the floor. The weld would cool into an amorphous pile, with the base of this pile flat against the floor. Once cooled this twisted lump of wasted weld would usually be discarded. César found a use for it here, welded onto the sculpture.