This chilling picture was taken in 1943.
It depicts the aftermath of a catastrophic event that befell a steam locomotive in Ohio,
USA.
What happened to this engine?
And if the train looks like that, what happened to the crew?
To explain this mysterious picture, we first have to understand the basics of how a steam
engine works.
An engine likes this uses fire to heat water in a boiler, producing highly-pressurized
steam that is used to drive the wheels.
The crew ignite and maintain a fire in the firebox.
This is done by burning solid fuel like wood or coal.
The heat and smoke from the firebox pass through an array of pipes as they make their way to
the smokebox and out the smoke stack.
The pipes they pass through are surrounded by water.
This is the boiler.
As the heat passes through the pipes, it heats the surrounding water in the boiler and turns
some of it to steam.
This steam is under a lot of pressure, and needs somewhere to go.
It passes through the steam dome on its way down to pistons that power the wheels.
In some designs, the steam must first pass through a superheater on its way out of the
steam dome.
A superheater reintroduces the steam to the flowing heat, turning the saturated wet steam
into superheated dry steam, increasing its thermal energy and decreasing the likelihood
it will condense in the engine.
What can not be understated is the extreme values at play here.
The incredible heat and pressure put a lot of strain and stress on the components of
a steam engine, to the point where many parts require periodic replacement to make sure
they're always up to the task.
These extreme values ensure that should any of these parts fail, the resulting release
of energy could be immensely destructive.
And that brings us back to this picture.
The locomotive here is a Chesapeake & Ohio T-1 class, numbered 3020.
In May 1943, residents outside Chillicothe, Ohio were shook by a monstrous roar coming
from the railway.
Upon inspection, the noise appeared to have come from a train sitting idly on the tracks.
The engine was hideously deformed and steaming debris lay scattered all around.
The three crewmen in the cab were badly scalded, all three would die of their injuries.
The boiler had exploded, forcing the superheater tubes out through the front of the locomotive,
explaining the image you see here.
What is not clear, is what caused the boiler to explode.
It's been suggested that the train had been travelling up an incline at the time of the
incident, slowing the train to a near-stall.
The crew, not wanting to stall on the hill, may have opted for less water in the boiler,
as less water is easier to heat and thus convert into more steam.
Adding water as this point would have cooled the engine, resulting in less steam and less
pressure, potentially resulting in a stall.
Water is an essential component of the steam engine though, and it's used for more than
just the creation of steam.
As the firebox heats the water, so too does the water cool the firebox.
A lack of water brings a lack of temperature moderation, under which the metal sheets of
the firebox begin to overheat.
The metal will turn red hot and begin to melt.
Keep in mind this machine is housing a volume of high-pressure steam strong enough to pull
many tonnes of train.
If part of that housing begins to fail, the steam will make its way out, explosively.
The brakeman, fireman and engineer were blasted with superheated steam, scalding them to death.
Some reports have the blinded brakeman explaining that he had begged the other two crew members
to put water in the boiler, just before succumbing to his injuries.
These old locomotives did not have the benefit of automated systems checks like we do today.
The crew was solely responsible for monitoring and maintaining the balance between temperature
and pressure.
In boiler explosions like this, insufficient water was commonly the cause, although such
explosions were rare.
And so, 80 years on, this picture is still strangely unnerving.
Even if you don't know what you're looking at, this image tells you that something went
terribly, terribly wrong.
What makes this picture truly horrifying is the fact that when you look into it, you learn
that being involved in this incident would have been far worse than even the terrifying
picture indicates.
The image suggests the relief of an instant death, though we know, that is not how the
crew spent their last moments.