Kelly Anderson posted:Pistons of this era are hollow and made of cast iron. Iron is a better bearing to the cylinder, and if the piston were made of stronger material, then something else would have to break at that moment of "immovable object vs. irresistible force", and many of those other parts are way more expensive than a piston.
And if I'm not mistaken that immovable object is typically water (condensate or water entrained in the steam from the boiler)?
Lew
