At the same time the two French scientists and philosophers D'Alembert and Diderot are working on their encyclopedia, a comprehensive work on the state of the crafts and early industry.
Diderot lists all metal-working trades, known at his time, Tubal-cain continues his tale: how Cain slew his brother Abel and of the mark that God put on Cain.
Metal appears on the scene: 12 dancers in metal costumes alight from a tramway at the beat of the percussion instruments and dance on the stagefloor of the square. While compressors and motor vehicles start up, Diderot continues writing: of the nailsmith, the brooch-maker, the knifesmith, and the gunsmith.
But Tubal-cain has not yet finished this tale: He himself is descended from Cain, he the "master of all coppersmiths and blacksmiths". Like Diderot and D'Alembert, he represents the past. Now, however, present-day steel-industry is taking the scene. We hear the sounds of the steelworks. D'Alembert is also working on his list: silver platers, boiler-makers, chasers, and minters are his contribution. But work proceeds unperturbed: turners, welders, fitters with angle sanders cannot be distracted by academic thinking. Work for them is a reality not the subject of scientific interest.
Accompanied by the sound of anvils, where iron is being hammered and molded, metal appears again. Diderot and D'Alembert have not yet finished their work. While they are still at it, metal dances.
As the Bible has preserved its validity through the ages, the story of Tubal-cain continues till "men began to invoke the Lord by name" (Genesis 4, 26).
Together Diderot and D'Alembert complete the chapter on the metal-working trades; they make their exit. Their shadow, their spirit, however, continues to live. Their work has rendered them immortal. Three boys appear: children to represent purity, aesthetics, beauty of work - they sing of the spirit animating the steelworkers, they sing of the Giant "Material", they sing of the "Iron Messiah".
Tubal-cain, who had meanwhile left the stage, enters again, not as a mythical figure but as the worker he once had been. He sings of the worker's longing for beauty and "forged flowers of iron".
Gradually unity, harmony prevails -all instruments are united into an overwhelming final crescendo on the notes g and e. Accompanied by these sounds, all participating workers at their machines tell their personal story, like Tubal-cain before, and a powerful final tone concludes this work from the Linzer Hauptplatz.