If you were the crew of an 18th or 19th Century sailing ship, and you were charting a course around South Africa’s Cape Of Good Hope, and by the look of it the weather was turning foul, your blood would have run like ice-water in your veins for two reasons.
First, the obvious. In an unpowered vessel, these were some of the most fickle seas in the known world. It wasn’t so much a problem of the waves smashing your ship to splinters (although that could happen, if the weather’s bad enough) - it was the currents. This is the point where the warm Agulhas current from the east (off Cape Agulhas, a rocky headland that marks the true southern tip of Africa) runs into the cold Benguela current from the northwest. It’s where two oceans collide, dragging remnants of their respective weather systems with them - and for a ship wholly dependent on the wind, it’s like sailing into a brick wall. Before the Suez Canal shortened the route eastwards, many an attempted voyage to or from India was defeated by the Cape, causing additional expense or even financial ruin.
But as that sailor standing on deck, you’d be more worried about the other thing. You’d know it when you saw it - and when you saw it, you were doomed.
“July 11th. At 4 a.m. the Flying Dutchman crossed our bows. A strange red light as of a phantom ship all aglow, in the midst of which light the masts, spars and sails of a brig 200 yards distant stood out in strong relief as she came up on the port bow, where also the officer of the watch from the bridge clearly saw her, as did the quarterdeck midshipman, who was sent forward at once to the forecastle; but on arriving there was no vestige nor any sign whatever of any material ship was to be seen either near or right away to the horizon, the night being clear and the sea calm. Thirteen persons altogether saw her ...
At 10.45 a.m. the ordinary seaman who had this morning reported the Flying Dutchman fell from the foretopmast crosstrees on to the topgallant forecastle and was smashed to atoms.”
That’s an account from later, after the myth of the Flying Dutchman spread to every corner of the nautical world. Every account would follow the same template: a sighting of an unidentified ship, accompanied by an array of supernatural effects - and later, some terrible event that would prove that the sighting was a prophecy of doom for at least one poor soul aboard your vessel.
But it seems to have started around the Cape, with the first recorded account dating from 1790:
“The weather was so stormy that the sailors said they saw the Flying Dutchman. The common story is that this Dutchman came to the Cape in distress of weather and wanted to get into harbour but could not get a pilot to conduct her and was lost and that ever since in very bad weather her vision appears.”
Pure fancy, cooked up by fevered minds as an outlet for their dread of rounding the Cape? Perhaps. Undoubtedly amplified by human imagination. But it’s also likely that the legend of the Flying Dutchman is explainable by something you can see outside your window on a very cold morning.
Imagine you’re by the sea, and you look out - and against all the apparent laws of physics, you see a ship almost at the horizon, but also above it. Hovering in the air, in much the same way that actual ships don’t.
But you’re not an 18th-Century sailor. You took science lessons at school, so you leap towards the right conclusion. Aha! It’s a mirage.
Ever look at a straw placed in a glass of water? If you look in from the side, it seems to bend, or be oddly broken. This is because when light passes into a medium with a different density, it refracts to a different angle (you may dimly remember this as Snell’s Law, from school).
You’re also right in considering the current temperature a clue. It’s telling you there’s a temperature inversion, where a layer of colder air is hugging the ground (a reverse of the normal state of things). And since cold air is denser than warmer air, that band of coldness is bending incoming light to form a superior mirage, where objects over the horizon seem much closer, and can even appear to be hovering high in the air.
Learning that light bends is a profoundly unsettling thing. Take the phrase “I’ll believe it when I see it”, often delivered as a rock-solid truism: if you actually can see it happening, surely that’s reality? This bias is so ingrained in us that when we see something like a magician’s illusion, we are absolutely fooled for a few seconds because, well, we saw it happening!
But really, we’re tricking ourselves. What we see is indeed, most times, exactly what we see. How we interpret what we see is the source of confusion here, and the thing magicians manipulate by focusing our attention in sneaky ways we’re barely aware of.
And in the case of the superior mirage known as the Fata Morgana (from Morgan Le Fay, King Arthur’s treacherous, scheming half-sister), we assume we can see ships floating in the air instead of an image formed of beams of light being curled down over the horizon towards our waiting eyes.
(Incidentally, if you’re lucky enough to see a Fata Morgana, keep watching it. As the air moves around, the moving light will create some very strange effects. Almost supernatural, you could say.)
So that’s probably the source of the Flying Dutchman myth - and it might also explain why the ghost ship appears to be moving in a way that’s absolutely impossible for the local sailing conditions, because it’s not local - it’s well over the horizon, in calmer waters.
So far, so weird. But let’s take this optical effect a mind-boggling step further.
In his bestselling book Landmarks, Robert Macfarlane notes that there is, in theory, no end to how far light could be curved in this way, including along extremely long-distance layers called ducts:
“Because the curvature performed within a thermal inversion is stronger than the curvature of the earth’s surface, light rays can be continuously guided along the duct, following the earth’s own curvature, without ever diffusing up into space.
In theory, therefore, if your eyes were strong enough to see that far, a duct would allow you to gaze around the whole earth and witness your own back and shoulders turned towards you.”
Now THAT would be a truly mythical sight.
See the Cape Of Good Hope for yourself (from land!) in April 2024, with Wheel & Anchor's multi-part exploration of South Africa's flora, fauna and dramatic landscapes culminating with a stay at one of Africa's top private safari camps. This two-part trip also takes in the exotic archipelago of the Seychelles in a remote part of the Indian Ocean. Get more details here.