The first thing you notice inside a locomotive cab is not the noise, though there is plenty of that — a low, percussive chuff that shakes the floorplates under your boots. It is the heat. Even on a January morning with frost on the coal, the backhead radiates a steady, muscular warmth that reaches through two layers of wool and settles in your bones. I spent my first hour in Cab 4472 with my back pressed against the tender door, afraid to touch anything brass for fear of leaving a burn.
The gauge glass never lies
Every locomotive man learns to read the water glass before he learns anything else. It is a simple vertical tube, brass-framed, containing a column of water that rises and falls with the boiler's fill level. Too low and the crown sheet overheats; too high and you carry water into the cylinders — a bent connecting rod, at best. The glass tells you what the fireman is doing two miles ahead of any other instrument.
"You do not drive a steam locomotive. You listen to it, and it tells you when it is hurting."
The last generation of men who could fire a locomotive by ear — who knew the difference between a thin fire and a deep one by the sound of the blower alone — are now in their seventies and eighties. When they go, a particular kind of mechanical intelligence goes with them.