No 6207 A Study in Steel 1935

Valves, cylinders, and pistons are the parts of a steam engine. The cylinders convert steam into mechanical energy. Under pressure, steam passes through cylinder valves into the chamber and drives the piston. Ahead is a very well-done film about building and assembling a huge steam locomotive from plain bar steel. It is nothing short of incredible to see how we work together and build a giant machine.