For humanity, it is the earth that is solid, and the air that is permeable; for chthonity, the opposite is true. They wander just beneath our feet, as we do beneath theirs, sometimes even atop one another. Their world is an inversion of our own, one which rests within a sphere atop an endless sky. Our atmosphere is the soil upon which they tread.
They are entirely unaware of our presence; to them, the sound of our footsteps is nothing more than a calming breeze. They have eyes, though they do not see light; rather, they see the complete spectrum of gravity, formed by the subtle tugs of nearby objects on their retinae. Because of this, the core of our planet serves many of the same roles for them as our sun does for us: it is a colossal orb of superheated matter high above which provides heat and sensory information.
Just as the roles of earth and air are reversed in their cosmos, so too are those of fire and water. Flames compose the majority of the anatomical structures beneath their smoky skin, and they find the heat of the inner earth to be pleasant (at least, in moderation). The oceans, on the other hand, are malevolent: tall, titanic masses of death that churn and foam, and extend as far as the eye can see.
Though intelligent, their tribes are not technologically advanced, for there is little in their world which can be used to craft tools. They burrow their way into the hollows of our canyons with their bare hands, or out the sides of our mountains (for the spaces between our mountains are their mountains). From there, they hunt other creatures of the same elemental composition, butcher them for their tender flames, and cook them over an open fountain.
They cannot know whether or not beings like us exist, but still, they wonder about us. They wonder about our mine shafts, and our wells, which to them, are towers which rise and solidify without explanation. And we wonder about them, and the way our buildings moan and shift as the world beneath us moves imperceptibly.
From a safe distance, chthons can see the opposite segments of sea serpents.
Waterfalls and dams can serve as accidental passages between our worlds.
Chthons are often mistaken for gnomes due to their shared habitat.
“Now, I could ask you how many moons the Earth has,” the professor began. “Wait for someone in the room to blurt the obvious answer of ‘one,’ then smugly rebuke them. It is within my rights as your instructor to do this, but I am not a jackass, and all of you are smarter than that. You wouldn’t be at this university if you fell for such banal tricks. You’d have suspected I was playing at something the minute I asked such a question. So, I’m going to be straight with you on this one."
Among believers, vaultgulls are said to possess golden feathers, as well as eyes of black crystal; then again, they are also said to have never before been seen, so such descriptions ought to be met with skepticism.
For these clever birds, all that is unseen is the sky; their wings slide cleanly through metal and stone as easily the wind. The only solid surface they know is the periphery of human vision, the greatest obstacle to their shimmering wings. The subtlest twitch of a single eye is enough to thrust them aside like a hurricane's gales.
For humanity, it is the earth that is solid, and the air that is permeable; for chthonity, the opposite is true. They wander just beneath our feet, as we do beneath theirs, sometimes even atop one another. Their world is an inversion of our own, one which rests within a sphere atop an endless sky. Our atmosphere is the soil upon which they tread.
“I’m telling you, the seismic readings are fairly clear at this point. It’s down there.”
“I mean, I believe you, but how?”
“From what I understand, the outer surface of the inner core is reinforced with hexagonal plates that hold back the sea of molten rock. There’s no external path inside- its body is armored in all directions.”
There are more than two-thousand species of bird present throughout the Great Agarthan Jungle, from the minuscule anteater hummingbird to the greater spherical penguin. Despite the extraordinary diversity present, however, all of their eggs, no matter the parent, are outwardly identical. Each egg is recognizably Agarthan by its signature gömböc curvature, gumdrop size, and transparent shell that reveals nothing but green jelly inside. If appearances are to be believed, there is no embryo within at all- just the same undifferentiated ooze.
If the tales of the old north are to be believed, when the gods created the world, they began by murdering a giant. Ymir, as he was known while alive, was disassembled into his most basic components, then used to sculpt the planet. Mountains were carved from his bones, forests were woven from his hair, and oceans were brewed with his sweat. Once this was done, his eyebrows provided just enough thread to sew the boundaries of reality shut. The last of these stitches marked the end of his usefulness, but also, the beginning of time.
Some mathematicians go so far as to call their work the language of God. In their hubris, they refuse to admit that they write in a language that is very human: one with its own idioms, clichés, and platitudes. In order to prove supposed mathematical truth, they routinely employ the same handful of phrases and arguments, yet are startled when these phrases and arguments are echoed back to them in the same language that they began with.
An ancient winter was buried in those caves, pressed between layers of geological strata. It was another kind of season from another kind of time, when the snow was luminous and refused to melt. After nine days spent lost in the dull, indigo glow of those tunnels, Thomas was no longer certain if the cold or hunger would kill him first. Almost all of his skin was numb, yet he could feel the outline of his stomach more clearly than ever before.
“So, where do we go from here?”
“Well, this is a maze,” she responded. “By definition, I don’t know which way to go.”
“Hmm. Then which way don’t we go?”
“The wrong way, clearly.”
The secret of your smartphone is that it is most powerful while turned off. In truth, its screen is the surface of an endless black sea shared among all others of its kind. Messages and information sent from one phone sink down through this vast darkness until they bubble up to the glass of another. All who gaze within are looking downward, no matter the direction of their eyes.
The gnomes of Hyperborea are neither born nor created; they enter our world by climbing out of their own shadows, and leave a few hours later when they inevitably tumble back down into them. At the bottom of each of these peculiar holes (sometimes over thirty miles in depth) is a pool of black lava of unknown origin. Some say that each such shadow is a window into a second underground, and that our planet hides multiple interiors beneath a single surface. Others claim that there is no such multitude of underworlds, and that the gnomes create a material debt by existing that eventually swallows their borrowed bodies whole.
There are chambers beneath the city where sound continues to exist without space in which to propagate. For most species, including human beings, these environments appear to be little more than solid walls of limestone and granite. For bats, however, these barriers are as permeable as the air they breathe. They dip in and out of the subterranean passages hidden beyond, preying upon the immaterial insects within.
Through rainfall, the dying hurricane entombs itself. The world below swallows what were once its clouds, beginning a process of transformation beyond human eyes. Eventually the weather above ground calms, but from the storm’s perspective, this is far from the end. Underground rivers become new arteries and reanimate its vaporous flesh, allowing mist and soil to merge into a new kind of sinew. After several weeks of gathering its bones back together, the storm returns to life in the depths of the planet.
You are waiting for a train at a station hundreds of miles beneath the Earth’s surface. The entire structure has been carved from what appears to have once been a colossal tortoise’s shell. A commemorative plaque attached to a column indicates that this is indeed the case, and that the station itself is “a relic from those chaotic days before the world was hammered into a sphere.”
The head of your pickaxe has been reinforced with depleted uranium. You swing its leather-bound neck with weary arms, and the honeycomb comes loose in thick ingots of iron-beeswax alloy. Throughout nine years of tunneling through the world’s guts alone, it has often served as your only friend.