The Explanation #
Marcus explains the "impossible" physics of steam to Rufus and Siro. "It's not magic. Water turns to steam, steam pushes the piston."
Rufus is skeptical: "You want to boil water inside a closed bronze jar? It’s a bomb, Marcus."
Marcus uses a metaphor they can grasp: "Think of a pot lid rattling when the soup boils. Now imagine that rattle pushing a lever. If the bronze is strong enough to hold the anger of the steam, it will do the work of fifty men."
Siro is intrigued by the wooden frame design: "It’s... it’s like a lung made of iron."
Rufus finishes his wine and picks up his heavy hammer: "If it explodes, I will haunt you. But if you want a bronze lung... I will cast you a bronze lung."