Damp, cold air sat thickly atop the Atrament, a chilling blanket of drifting mists above the dark and gently lapping ink. It was pretty much the coldest Alice had ever been in the Library, which normally seemed to maintain a balmy approximate room-temperature, but it wasn’t nearly as cold as some of the places in the Arboretum, so her concession to the chilliness was to pull a jumper out of A Librarian’s Satchel of Inconsistent Inner and Outer Dimensions and to mostly stay inside the ship’s cabins, looking out as wisps of fog passed by, lit by the lights on the boat and by occasional distant flashes, glimmers of pale green-blue light, luminescence that brought unsettling images of a deep sea angler fish’s lure to her mind.

It was the third day of travel. Zkrith – short for Zkrithlinos, apparently – spent most of her time steering the boat with a series of levers and cranks arranged in bewildering array across a brass instrument panel in the ‘bridge’. Most of the rest of her time was apparently spent tending to the engines – things that apparently were fuelled by ‘hermetic principles’, whatever that meant, and spent most of their time either making weird almost musical noises or belching the occasional cloud of green-and-violet smoke from one of boat’s small forest of chimneys. At the latest muffled bang from the engine rooms, definitely off-limits to non-crew, Alice’s curiosity got the better of her.

“So,” she asked, to no-one in particular, “what does ‘hermetic’ mean, in this context?”

“The engine lives in a hermitage,” said Aidra.

“Anyone else?”

“I think these kinds of boats operate on principles of opposition,” said A Librarian.

“Yeah,” Nik continued, “very precise equilibriums of natural forces can be harnessed to provide direction or impetus to a vessel. I’m no expert, but I doubt you needed or wanted an expert’s explanation.”

“It’s magical, basically,” A Librarian finished with.

Aidra, however, wasn’t finished. “Imagine, if you will, two opposing poles. On one end, a bonsai tree, mounted firmly in a bracket at one end of the alchemical transmitter.”

She raised an eyebrow. “…Right?”

“No, silly, at the front, and I think that’s starboard on a boat. At the other end of the engine is the true opposite. A – drumroll, please – a hoover.”

“A hoover.”

“A hoover!”

“A hoover?”

“A hoover! The opposing poles are so repelled from each other, see, that enough force is generated for the boat to move forwards! The asymmetrical nature is a bit fiddly, but that’s because while the tree’s antithesis is the hoover, the hoover isn’t particularly bothered. So you mount the tree at the front of the engine so it doesn’t go backwards. The aft, I think, because we’re naughty-cal.”

“I’m going to regret asking this,” she said, pinching the bridge of her nose, “but why is a hoover the opposite of a bonsai tree?”

This narrative has been unlawfully taken from Royal Road. If you see it on Amazon, please report it.

“Surely, it’s obvious?”

“No, it really isn’t.”

Aidra grinned. “Nature abhors a vacuum.”

She groaned. “Nik, can we keel-haul your brother? Or, at least, make him walk the plank a little?”

“Now there,” said Aidra, “even if that wouldn’t keel me, you should take an even keel and even then, this boat doesn’t have a keel.”

“Yes it does,” said Zkrith, who had silently appeared in the doorway – an impressive feat given her hooves.

“Please tell me,” said Alice, “that the engine doesn’t run on a bonsai tree and a vacuum cleaner.”

The tall devil blinked, confounded for a second. “Uh, no? I mean, that’s a fairly elementary oppositional pair, and the force generated is too low to get a vessel this size moving.”

“Gods dangit, he was saying something plausible?”

“I’m the one you’d least expect to!” he exclaimed in gleeful response.

“In case you’re wondering,” said Zkrith, “the engines operate on a Cardinal Cycle – they generate an offset in direction by carefully-balanced alchemical and alkahestric reactions. The musical noises are it working well, and the, er, small explosions are it malfunctioning.”

“Oh, like a car backfiring.”

“What’s a car?”

“You have trains and boats, but you don’t have cars in the Realms?”

“Cars are a smaller relative of trains,” Nik explained.

“Yeah, kinda?” said Alice.

“They’ve usually got… four legs per segment, whereas trains have six or more.”

“Uh. Not actually, kinda. At least, not where I came from.”

“I feel both less and more informed at the same time,” Zkrith muttered audibly.

“So what does the engine run on, then?” Alice asked.

Her face brightened. “Ah, yes! It gathers its fuel by an alchromatic process I designed myself, ‘skimming’ the colour from the very ink of the Atrament! With only a little more automation, it could very well run perpetually!” She paused for a second, reconsidering. “Well, apart from the fact that the breakdown of the ink into its constituent chroma being quite so caustic, which tends to eat through the pipes unless I keep them maintained, but that’s just an engineering problem at this point.”

Twelfth was standing outside the cabin, but her voice was unmuffled, and she could apparently hear what they were saying. [Fascinating. I Recall When The First Alembic Traction Engines Were Created.]

“Well, you would, wouldn’t you? I’m from Sheol, not from around here, but Bookbinders are bonkers old, aren’t they?”

[Define ‘Bonkers’.]

“Touché.”

[If Anyone Is Interested, There Is A Pod Of Trolval To Our Starboard.]

“A pod of what, now?”

The endless rippling darkness of the ink, stretching off into the gloom, was broken occasionally by the glittering undulations of the Trolval. Alice didn’t know what they looked like in full, but there were occasional features visible, great jagged fins, spouts that spewed ink in fountains through the air, and gleaming eyes, all set among white scales, covered in coiling blue patterns like an antique vase from her grandma’s house. There were several of them, as far as she could see, and they were enormous, the humps of their bodies breaking the surface easily as large at the boat they rode on. She couldn’t see how big they truly were – the ink was completely opaque, so all she saw was the stark paleness of their scales, ink running off the glaze in rivulets as they rose above the surface, before dipping back down into the unknowable depths.

“Do they ever… damage boats?” she asked Zkrith, sounding only slightly worried.

“Can’t say I’ve heard of it,” she replied, leaning against the rail at the edge of the deck, smoking something unidentifiable in a long-stemmed pipe. “I think they’ve got pretty good sonar, so they don’t really get close to anything they don’t think is food.”

Ahead of the boat, the nostrils and then great foaming spouts of an enormous, crocodilian head rose above the ink, jagged teeth that must have been more than six feet long briefly glinting in the boatlights as the Trolval yawned with a tremendous rumbling noise that Alice could feel vibrating through her bones more than she could actually hear it.

“Well,” she squeaked, “I’m glad we don’t count as food, then.”