The last Big Boy ran in the early 60?s sound recording back then was not what it is today for sure. I can only imagine what one of those beasts under load must have sounded like in person. It is great that some rail fan took the time to record these and other locomotives on film and tape and then got them transferred from the original (8mm ??) films to a digital format.
I worked my way through college at an industrial supply company. In those days many of the textile plants were still in New England and all of them had honking big steam boiler plants. All were oil burners by this time, but a few were converted coal burners; some firemen had their shovels chrome plated and mounted hanging in the boiler room. Something I should have taken a picture of, but sadly never expected them not to be there. Today not only are the jobs gone, many of the buildings are too.
A big water tube boiler without a fire in her box is just a thing; but with steam in her chest she turns into a living breathing entity. She needs food (fuel) air, water, a spark to bring and keep her alive. As she comes up to pressure she creaks, pops, and groans. The sounds of compressors and pumps fill the plant; soon you feel the heat start to build, the acrid scent of the un-burnt oil and smoke start filling the air. It?s a dangerous time, she is just as apt to blow out or up as run; until she is hot she?ll

and moan resisting the building pressure pushing out water or wisps of steam at joints that have yet to expand and seal. As steam fills her drum the balancing act begins. Her blow off valves are teetering between being open and sealed, the engineer?s black art and skilled hands working the valve, that allows enough of her steam out of her into the plant, but not so much that she dies waiting for her condensate to return to keep her alive, or feed water valves to open and drown her . His eye will be glued to the pressure gauge that gives the clue to what her next move will be will she blow or go. Soon she will be purring like a contented cat, but now she is fighting like a caged tiger, belching clouds of sooty smoke out her stack. And that is just a stationary power plant; put wheels under her and they must have been magnificent.