The steel sections appear to be holding the rocks up.
The steel sections are joined by brazing - not welding.
Cast-iron members generally heat up more slowly than equivalent steel sections.
This translates to three times more deflection in an aluminum mullion compared to the same steel section under a given load.
The chassis was designed by Charles King and consisted of steel sections bolted together.
The thickness of this intumescent coating is dependent on the steel section used.
The tanks empty and shrink over a period of 14 hours, with five steel sections that telescope into one another.
It's glass cloth, gasketed onto the two steel sections it joins.
During the production of steel sections the bar has to be repeatedly put through rollers.
Rotting steel sections can be repaired as well.