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  • Paul Anthony Jones


(n.) someone who lives in a polar region

Last week, we tweeted this:

And, as is always the case with unassuming words like this one, scratch below the surface and there’s a superb story to tell.

The word periscian was adopted into English via Latin, but has its roots in Ancient Greek. Coined in the second century BC by the Greek philosopher and geographer Posidonius, periscian brings together the Greek words peri, meaning “around” or “encircling”, and skia, meaning “shadow”.

The peri found here is the same peri– that crops up in words like perimeter, periscope, and periphrasis (“longwinded, roundabout speech”). It also turns up in period, which meant “circuit” or “cycle” in Ancient Greek; in Pericles, whose name literally meant “famous everywhere”; and in peristalsis, the wave-like muscular movement that pushes food through the digestive system, which means “contracting” or “constricting around”.

Skia is much less familiar, but it nevertheless crops up in a handful of (fairly obscure) English words like sciatherics, “the science of using shadows to tell the time”, and skiamachy, a formal name for shadow-boxing or, figuratively, a sham fight or angry dispute. It’s also found in the adjective sciapodous, meaning “having large feet”—but that’s a word that deserves its own blogpost at a later date...

But how does a word meaning “throwing a shadow all around” come to refer to someone who lives at the Poles? Well, the answer all has to do with geography.

sunset in the arctic

One of the subjects that most interested Posidonius was the size and arrangement of the continents. Writing in the second century BC, he came up with a method of dividing all of the lands on the surface of the Earth into three different latitudinal bands or zones—which he called the Amphiscian, Heteroscian and Periscian—based on the shape and position of the shadows of the people who lived there.

This “Posidonian” system of dividing the Earth was then picked up and expanded on by other scholars and geographers, including Cicero, Plutarch, and Strabo (who considered Posidonius “the most learned of all philosophers of my time”). As he explained:

Amphiscians are all those who at midday have their shadows sometimes projecting this way, to the north ... [and] sometimes in the opposite direction when the Sun changes round to the opposite way ... This happens only to those who live between the tropics.
Heteroscians, on the other hand, are either all those whose shadow falls to the north, like us, or all those whose shadow falls to the south, like the inhabitants of the southern temperate zone.
Strabo, Geography (c. 7 BC)

And that left the Periscians—namely, all those who dwelt at extreme latitudes, where uninterrupted sunlight during the summer months will cause their shadows to “traverse in a circle” around them. So while the Amphiscians literally had “both-way shadows”, and the Heteroscians had “same-way shadows”, the Periscians were wholly encircled by their shadows, like the spike on a sundial:

PERISCII are the inhabitants of the two Frozen Zones, or those who live within the compass of the Arctick and Antarctick Circles; for as the Sun never goes down to them once he is up, but always round about, so do their Shadows. Whence the Name.
John Harris, Lexicon Technicum (1704)

He might have invented the term, however, but Posidonius came to a somewhat misguided conclusions about the Periscians—he didn’t believe they existed. In a later discussion of the size of the lands of the Earth (that only survives in a fragment today) he wrote:

Periskians are of no importance in relation to geography, for these parts are uninhabitable because of the cold ... So there is no need to worry about the size of this uninhabited land.

Now, that’s cold.

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