Steel Trim
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Engineering, Magic, and Kitsune Ch. 44
🕑 Added 2025-08-27 14:31:41 +0000 UTC"I think the easiest place to start would be with a practical demonstration," John mused.
Almost idly, he grabbed his waterskin and a pair of ceramic bowls from a nearby shelf, pouring himself some water in one. The second bowl he awkwardly propped up above the water with two small boxes.
Fuck, would he even need an anode?
Probably, but magically summoned lightning was weird and didn't behave like it should, regardless. John's setup for de-rusting stuff needed an anode, although the odd entropy and order shell he used to direct this focus may cause some oddities. "Normally, I do this a bit differently, so please bear with me if it doesn't work immediately," he explained, excusing the likely imminent failure.
Looking around, John grabbed a pair of daggers from the ground, their owners having abandoned them in their flight to escape earlier. While he didn't expect significant corrosion from this little experiment, he still didn't want to sacrifice the perfectly good cutlery he had packed. At least he didn't have to worry about electrocuting himself, given how intensely durable his warding was.
He swapped out his focus while Rin was staring at the strange setup, then hovered his finger barely over the water, leaning one knife against his finger where the emitter was pointed, then another against his hand. He twitched his hand just the right way and unleashed a continuous stream of low-powered electricity into the blade.
Thankfully, the water started to bubble quietly. Internally, John cheered. Outwardly, he was all sage nods and calm gazes.
"So, magically speaking, water might be close to a pure element, but physically? It's not even close. To simplify things a bit, since water is one of the most annoyingly complex substances, it is composed of two pieces of an element called hydrogen and one of an element called oxygen. I'm afraid I don't know if there are words in your language for them, but they are the first and eighth element, in order of weight," John rambled in a tone more conversational and electric than what lecturers would usually take, only briefly stumbling when he had to use English words.
Turned out that only having to teach something once rather than six times that day would do that.
"It's almost like it's boiling, but…" Rin curiously murmured, leaning in, staring at the small bowl as the water bubbled and churned. She placed her hand against the outside of the bowl of water, drawing a flinch from John, but he supposed someone as resilient as an Unbound probably wasn't worried about getting a tiny bit tased. "It's still cool. How many of these base elements are there, if water isn't one of them?"
"Oh, there are a few levels below this one, but those aren't relevant. For now, at least. Anyhow, last I checked, there were one hundred and eighteen of them," John casually explained.
Rin choked on her own spit, and her eyes bulged. "One hundred eighteen!?" she loudly repeated.
A beat passed, and she reddened.
"Pardon my outburst, sensei. Do I…" Rin trailed off, looking conspiratorially around, and when she next spoke, it was almost a whisper. "Do I have to memorize all of them?" Rin questioned, unmistakable terror soaking into her voice.
John laughed. He couldn't help it. Not a little, baby chuckle, either. No, this was a rich, deep, belly laugh that shook his core and made his lungs cry for air. Fuck, she reminded him of himself in weird ways; that was the same primal terror he felt when he thought he could manage organic chemistry in university as an extra science credit! In a way, that thought was terrifying given her Rin-ness, but he pushed that aside for now to soak in the moment.
Now, her pale lips pulled tight, and she leaned back, slitted eyes glancing at the exits, legs twitching uneasily, like she was ready to get up and flee academics after she refused to flinch at the idea of Nameless or bandits. All the while, her tail was frozen in place. He hadn't even thought about it before, but the long, black-scaled serpentine limb that trailed behind her constantly moved, at least a little bit. Mostly subtle wriggling motions, like she was some great snake swimming through the sea. Now, though? It was ramrod straight, like someone was grabbing onto it and pulling.
"No. I'm not going to expect you to memorize many of these. Really, if you have to deal with Flerovium, something has already gone horribly wrong," he calmly explained.
All at once, the tension bled from Rin's form as she uncoiled, no longer ready to cause a lot of damage in a frantic attempt to go in five directions like a coil spring being put in by a backyard mechanic.
Wait, why the hell does he remember Flerovium? Atomic number one hundred and fourteen, atomic mass about two hundred and ninety—
Well, that was weird. John shouldn't be remembering stupid details like that, should he? Hmm. That was maybe something he should check out later.
"Anyhow… As mentioned, water breaks down into hydrogen and oxygen. The former may be new to you, but the latter, well, it's what you breathe! Part of it, at least. Oxygen is about two-tenths of the air, and it's what your body needs to work! Air and food go in, energy goes out."
The gears continued to turn in Rin's head, and she turned from staring at him to staring at his little construct. "Ah! That's why air turns bad when something gets locked in a box. Then why the bowl? If it's just going to turn into more ox-gen and hidro-gen, isn't it just going to mix with everything else?"
That was a surprisingly good attempt at the pronunciation, and he had to give her props for that. Better than he did with these quasi-Japanese words for the first time. "Oh, that's for the hydrogen. It's lighter than air and isn't normally in with the stuff we breathe. It goes up for the same reason that oil floats on water."
Oh shit, he hoped Rin didn't question why water and oil didn't mix when other things could. He couldn't even begin to imagine trying to explain polar vs. non-polar molecules off the cuff with this language barrier. They'd have to get into charges, he'd have to teach more about how water is a weird freak substance, and—Ugh.
Why couldn't life be based off a less frustratingly complex chemical? It'd make things a hell of a lot easier to explain to someone with no chemistry background.
The pale, dragon-blooded woman laid down, spinning around like a cat to look up at the bottom of the bowl. "I can't see it, sensei," she said, leaning in to sniff before he could stop her. "It smells like nothing, too."
Fuck, he was pretty sure hydrogen gas was non-toxic, right? Besides, she had her Unbound physiology to fall back on. Rin would be okay, probably. "You won't, it's odourless," he stated, burying his frayed nerves between what he imagined was a wise tone. "Also, please don't randomly sniff things I'm making. Some of them might be dangerous."
Rin didn't say anything but reddened and scooted away as her expression quirked up in embarrassment, refusing to meet his gaze.
John stared at her for a long, long moment, considering how she managed to survive this many decades. He got that she was superpowered, but she didn't come out of the womb like that, right? Then again, he met many people back home with either no common sense or self-preservation, the type where he imagined it was a full-time job to stop them from putting shiny metal in the funny wall sockets when they were young and even less inhibited.
"So, you can make a flame, right?" he asked, shutting off the flow of power through his gauntlet and withdrawing his hand. It was starting to chafe, but he would endure, even if he was already missing the better glove.
Admittedly, it seemed like "make a fire" was one of the most basic things someone could do, but with how specialized Unbound seemed to be, he wasn't entirely clear on whether they lost access to those basics if they didn't fit their 'theme.'
She looked at him like he had just asked if water was wet, albeit more politely. At least she didn't seem insulted; more confused than anything. "Of course, sensei, my teachings weren't that bare," she replied, albeit with a little huff at the end.
He reached over, grabbing a long-ish chip of wood from the remnants of the barricade, tossing it over to Rin, who caught it with cat-like reflexes. Without waiting for his queue, she ignited it. "Do I just… stick it in?" she hesitantly asked.
John suppressed a snicker at her phrasing.
He initially thought about tipping the upside-down bowl to let some hydrogen out. But, you know, that bowl was pretty small. It probably wouldn't be too big, and Rin was super durable anyhow, and he had his warding.
It would be pretty funny.
"Yeah, go ahead," he laxly remarked, waving off her concerns.
He swapped the focus in his gauntlet to the freezing one, just in case.
Rin maneuvered to sit up with inhuman fluidity and grace, less pushing herself up and more spinning herself into a sitting position without using her arms. Extra to a degree hardly ever seen, but impressive nonetheless.
Her brow furrowed, and she slowly brought the flaming piece of wood closer and closer to the bowl, completely ignoring how the flames licked at her fingers, pale skin unmarred by the heat. Closer, and closer yet to the ball of flammable gas.
Perhaps this was a bad idea.
His carefully crafted smile faltered. "Hey—"
BANG!
Rin was in motion even as the fireball bloomed into a small, but very, very brief inferno, the loud explosion echoing in the room as the ceramic bowl lifted a few inches from where it rested, the flame a bright red for the instant it existed before winking out of existence and leaving spots in his vision. He did not yelp and would deny any accusations.
Rin was already in the air with a yelp, tail and limbs whipping wildly as she flailed, trying to right herself. Her antler-horn things scraped against the ceiling, carving deep grooves into the wood before they suddenly dug deep into it, but her body kept moving, slapping her legs into the same beam she was stuck in. After, she dangled like a limp noodle, awkwardly hanging from the roof, red as a tomato, covering her face with her hands.
"...Hey, uh, Rin, you okay?" he carefully asked, standing back up, eyes locked onto the dangling woman, who seemed to shrivel up at the question.
"Yes, sensei," she muttered quietly, barely loud enough to hear. She tried to nod but, with her head stuck, her body wobbled in the air like a leaf in the breeze, showing a frankly impressive amount of neck strength.
On one hand, he was rather concerned, even if he had seen her take worse during the fight with Yuki, but on the other hand…
A grin threatened to force its way onto his face, but he stopped it. It'd be improper. Send the wrong message. So would the laugh threatening to burble up out of him. "Hold on, let me get you down."
"There's no need, sensei!" she answered far too fast. "I can free myself." She reached up, eyes closed as if she couldn't bear to look at him, before wrapping her arms around the beam, wrenching it roughly and making it creak ominously.
The whole beam. And the things it was attached to, too.
"Hold it!" he quickly ordered. "That's load bearing, I'll get you out."
She halted her efforts, but said nothing, only going to cover her face once again, releasing her grip on her antlers as she hung like a demented Christmas decoration.
He would not laugh. He would not.
A little smile wasn't out of the question, though. Rin wasn't looking, anyway.
John swapped in the telekinetic focus and tried to grasp Rin, only to have the power fail to grab, as if it was sliding off her, completely rebuffed.
Oh, right, the whole… Aegis thing. It was silly of him to forget that. There was a reason he had so many methods of self-defence beyond just levitating his targets off the ground so they couldn't hurt him. It seemed like the only way to directly afflict someone bearing an Aegis with any sort of effect was to deplete the field first. Possibly, based on what he had observed between yokai, the defending party might be able to drop it and let something happen.
"Rin, would you mind relaxing a bit? I can't levitate you down like that," he cautiously ventured. Thankfully, if she was confused about whether it was possible, he could blow it off by saying his methodology allowed one to do so, which was technically accurate, in a way. She already knew he wasn't a traditional Unbound, after all.
No response.
"Rin. If I can't, either Yuki or I will have to physically grab you to get you down. Do you want that?" he gently inquired, Rin stilling like the thought had slain her on the spot.
He let the silence hang heavy between the two, and the room was as silent as a tomb for a good minute. "Please don't," Rin pleaded, and he could see even more red on her cheeks at the edge of her hands. "I'm ready," she finally replied, after some more time steeling herself.
Sighing, he tried again. This time, there was no resistance to his telekinetic grasp as he remotely unwedged the poor woman, working Rin back and forth like a stuck nail before freeing her with a muted crack. Thankfully, the beam remained intact enough, and he didn't have to hurriedly try to patch it to stop the roof from collapsing in on them.
"You alright?" John asked Rin as he set her back down on her feet. Almost the second she touched the ground, her Aegis flared back to life, cutting his magical grasp from around her.
"Sensei, is it possible to die of embarrassment?" the dragon-blooded Unbound asked, finally removing her hands from her face. She was still violently, aggressively red like she had just gone out sunbathing and missed a few spots. Honestly, the range of colour was impressive, and if he didn't know what type of reptile she had ties to, he would have been tempted to guess that it'd be a chameleon.
Are dragons reptiles, actually?
"No, fortunately, I would be dead a dozen times over if so," he added.
She cracked her eyes open and gave him a baffled, almost disbelieving look.
Most of these stories didn't really bug him nowadays, but he had a few that certainly made him want to curl up under a desk and never come out at the time.
"Once, in my schooling years, when I knew just enough to be dangerous, I tried to make something that cooked my breakfast in the morning without my input. I nearly burned the entire building down and was banned from cooking on the property, on pain of removal. Today's embarrassment, tomorrow's funny story, you know?" During his first year of university, he wired a hot plate straight to a plug, bypassed the power switch, and hooked the whole assembly into a lighting timer switch for Christmas lights, leaving food that would keep overnight on it. It worked fine for the first time, but then he forgot it would do the same the next day, and when some leftover grease spat, it caused a minor incident that only needed everyone to evacuate for an hour or two.
The way Rin stared at John made it clear it was hard for her to imagine him ever needing to be taught, all wide-eyed.
Nonetheless, some of the red had faded.
"To be fair, I could have told you what would happen, so most of the blame rests on me," he admitted, "but I thought this would help make the lesson stick." And that it would be hilarious. Rin hurtling through the air like a cat confronted with a devious cucumber certainly delivered on that account.
Hesitantly, she nodded. "I understand, sensei. I don't think I'll be forgetting today for a while."
He let a little snort escape—just one. "Right, so, water splits into hydrogen and oxygen," he explained, pulling a piece of paper and some writing implements from his bag and quickly drawing the formula along with some visual aids. "We'll go over the rest later, but oxygen is a big part of what our bodies need to breathe, and hydrogen has many uses, but it is very, very flammable."
"Is this how fish breathe underwater?" Rin curiously asked, tilting her head to the side.
That wasn't a bad guess for someone who knew nothing about this.
"No, but that was a good idea! Keep asking questions!" John praised. "Respiration… essentially, the way your body gets usable energy out of stored energy requires oxygen, which is a part of air, and then you exhale carbon dioxide, which plants then suck in as part of the process to draw energy from sunlight, releasing oxygen. It's a cycle, you see?"
"A cycle," Rin muttered, a spark forming in her eyes as she seemingly drifted off to somewhere else. "It always comes back to cycles, doesn't it?"
"Usually," John confirmed with a shrug. "The world's big, but it's not infinite, and it's been around for a long, long time. If things like that didn't sort themselves out, the place wouldn't be here for more than a few millennia at most."
The silence wasn't tense, it wasn't heavy. It just was, and although John loathed to disrupt Rin's chain of thought, he filled it anyhow, after writing down some notes to give her. "You know, you can do a lot with electrolysis under the right circumstances," he stated. "You can coat metals in silver, gold, or many others, break things down into their components, purify metals, extract ores like aluminum, and do plenty of other things!"
Rin nodded along before suddenly freezing.
"Wait, aluminum?" she hurriedly asked.
"Yeah? Dirt common metal, light, silvery? It's about the third most common element in the rock we're standing on. Well, maybe not here exactly, but in the world we're standing on as a whole."
"John, aluminum is rarer than the bones of high dragons. The production has been a secret for generations, with the hidden mines locked up as tight as any vault!" she hurriedly whispered, even as he subconsciously slid the sheet over to her with his various quick notes.
Rin held it like a holy artifact.
Slowly, John's mind switched from industrial processes to the history behind them, long disused gears starting to turn.
"Huh. Interesting," John muttered, and a new idea formed in the back of his mind.
Comments
Nicolas Guay
Wait, that's one way to starve the unnamed right? You could give them alot of aluminum, and then drown the price with cheap aluminum, that would both make some money and bring problems to the unnamed right? The problem with previous solution was that it needed to drown something like the tools Smith market or something, Which could be a problem for the inhabitants. Using aluminium can solve this right?
Unwillingmainer
Some fun chemistry lessons that might have far reaching consequences. If they live long enough, Rin is going to be a right menace and Yuki is going to be even more so. And John will likely be as rich as Yuki can make him and at the head of the magical industrial revolution.
TopBat
They found SOMETHING, that's for sure. Someone has some means of getting aluminum... and isn't sharing with the class.
Vlad Cold
Funnier thing is... in our world you basically can't get aluminum in pure form without some form of electrolysis. Early methods of obtaining aluminum were using sodium amalgam which is (surprise) cannot really be obtained without electrolysis in our world and was obtained in mercury electrolysis cell. So... if locals do not know about electrolysis, only way they can get aluminum is freak magic accident or some advanced technique working like plasma beam decomposition in vacuum.
Trevyn Lane
Rin is showing that less technologically advanced doesn't mean stupid... though she is a bit unwise and reckless. You can easily explain all kinds of things to less technologically advanced people, but for the most part they have limited uses for a lot of these things as survival takes priority.
An_Reader89
He meant electrolisis I believe, not the hydrogen itself.
Vlad Cold
I'm not sure what John remembers, but so far there is no known process for recovering aluminum from alumina with hydrogen 🤨. With magic, you'd have better luck with alumina decomposition in vacuum with electricity... do they even capable of producing alumina?
Vlad Cold
Nah, it would explain better memory on subjects he USED, but what use he had for knowledge on Flerovium🤨? So far, two plausible explanations: Ki effect overall or Yuki influence on his brain.
Michael Halpern
i suspect his improved memory happened when he was brought to this world, his projects have involved some impressive math, he has just been so busy working on them that he hasn't realized.
Michael Halpern
most likely the mines are either the exceedingly rare native aluminum, or they are brute forcing the process with magic.
Michael Halpern
hmm way to kill the nameless without necessarily wrecking the economy.
Between the Space
Fun story with aluminum, it's crystallization was discovered by accident if i remember correctly. The concept was believed to act just like how iron turns into steel under intense heat and pressure. And they were correct however unlike steel, aluminum takes time to crystallize. A chemist/forger was playing with it and then toss it to the side thinking that he failed again but when he came back the next day he found that the aluminum had crystallized. That is if I'm correct
