Physical Therapy (1)
“Hiiiiiiieeee!!”
“Hyah!”
The Rodria family’s party came to a halt on the mountain path as an obstacle blocked their way.
“What is it?”
“There appears to have been a monster attack here, sir.”
At the words of the knight at the front, Gilles stepped down from the carriage and examined the traces of the assault.
“...This is.”
Scattered goods and a torn red banner littered the ground, along with torn lengths of cloth flung every which way.
“Urgh...!”
One of the knights turned his head and retched at the ghastly sight.
Human corpses had been reduced to lumps of meat. Shapeless masses the beasts had chewed and spat out lay strewn about without order.
Frowning, Gilles picked up a scrap of clothing from the dirt.
“Jacky’s clothes.”
“The goods on the ground are Raven Merchant Guild stock as well.”
All of them had died in the monster attack.
Gilles felt no pity for them. As far as he was concerned, they had simply reaped what they sowed.
“Gather what you can. We can’t take all of this, so prioritize the valuables. And be sure to find and bring the Core of Tellurox.”
It was the single most precious item Jacky had carried on this caravan after the Zephyrs themselves—a magic material worth hundreds of gold at the very least.
“...I don’t see it.”
“Impossible. Look harder.”
“It’s strange. Most of the goods are still here—only that is missing.”
“No—several of the valuables are gone. Was this not a monster attack after all?”
No matter how he looked at it, the traces said they had died fighting monsters. And yet only the valuables had vanished...
“Perhaps travelers who came through afterward took them.”
“Through a place this dangerous? For now, just take what we can from what’s left. We could be attacked ourselves.”
Questions remained, but Gilles wanted to leave this ominous stretch of road as soon as possible. Traces of those who had fled toward the highway and died there were scattered about as well—not only in this immediate area.
Now I understand why the Mardin Principality is so isolated from the other nations of the continent.
It was more dangerous than the harsh mountain terrain alone. Ordinary people would never want to come this way again.
But Gilles had no such intention. If anything, he found it fortunate.
This works out perfectly. Now only we and the Pacific Merchant Guild know of the golden egg that lies here.
Whether Selena Kaders would ever return to the allied nations again, he did not know—but if she did, he meant to cooperate with her absolutely. And with the Raven Merchant Guild reduced to this, all the more so.
“The workload just blew up all of a sudden.”
Time to sort through what needed doing.
First: the massive construction for the sewage system and the electricity supply facilities. He could leave that to Builder and Fenri.
Next: building an academy to train engineers and researchers. The teaching materials for them were already being prepared, step by step.
As instructors, Andersen and Alvar would do for a start. With proper training, the three apprentice researchers from Helec could also serve as academy lecturers.
Beyond that, he needed to provide manuals of standardized units of measurement—mm, cm, m, km, and the rest—for blacksmiths, architects, tailors, and every other kind of specialist craftsman.
Until now, people had measured everything by eye, by rough guess, or with body parts and tools. That would no longer do.
The ancient textbooks of Teisreia recorded that they had already invented and used units of their own. The problem was that no one knew how long those units actually were.
So from the moment he built the milling machine, Robon had used the principle of the pendulum to establish a standard unit, and he had kept using it inside his laboratory ever since.
The three apprentice researchers from Helec had barged into his room with questions.
“So if you calculate it mathematically, you can produce a fixed length?”
“That’s right. You’re the one who seems to grasp it best so far.”
He did his best to answer every curiosity they threw at him.
“This meter thing was made from a natural phenomenon? That’s so cool!”
“Rebecca, be quiet for a second. You’re distracting everyone. Tch.”
Darius scowled hard and stared again at the pendulum Robon had made.
“A pendulum has a natural period that depends on its length. If we call that period T, then T equals two pi times the square root of L over g. L is the length of the pendulum, and g is the acceleration due to gravity. I’ll prove how that formula comes about later—for now, just memorize it. What you need to know right now is this.”
The time-honored tradition he had grown up with back in Korea: if you don’t understand it, memorize it first. He couldn’t prove every law and concept on the spot.
“If the acceleration due to gravity is 9.81 meters per second squared, and we set the pendulum’s period to two seconds, we can solve for the length. That comes out to roughly 0.994 meters. Follow so far?”
Aside from Grent, the other two only tilted their heads. This was a method he could use only because he carried modern knowledge; it was never going to be easy for them to absorb.
Strictly speaking, there was no guarantee this world’s gravity matched Earth’s. But simple drop tests and pendulum trials suggested the difference was not large. If gravity had differed dramatically, an environment this similar to Earth could never have formed in the first place. Even with a slight discrepancy, the resulting length would not swing by much.
More importantly, this was only a standardization of units. Even if gravity was a little different, everything would simply form around the unit he defined now, so the work itself would be fine. Consistency had been the goal from the start. He planned to measure gravitational acceleration properly later and recalibrate. Length could be redefined then as well.
“Going by what’s given, I understand it.”
“From there, you hang a weight on a string, keep the center of mass steady, and adjust the string’s length until the pendulum’s period is two seconds.”
In truth, plenty of variables remained—regional differences in gravitational acceleration, the difficulty of measuring time precisely, and tiny real-world errors like friction and air resistance. But in the present situation, this was the best he could do. Without standardized units, you couldn’t even use something like a vernier caliper, and fine machining became impossible. Once he could calibrate time accurately as well, he would redefine length afterward. For now, they would work with this.
“But wouldn’t the result change depending on the mass of the weight?”
Darius asked his first real question.
“Good question.”
“Haha! Wasn’t I sharp just now?”
“Ooh! That’s Darius for you!”
“True. If the weight changes, the result should change too.”
“For that, you need to know something called Newton’s laws of motion. All of this is a concept they used back in ancient Teisreia.”
It wasn’t, of course. But as an excuse, nothing beat Teisreia.
“When the pendulum moves, the force of the bead’s weight is F equals m times g. Combined with the equation of motion, that becomes a equals F over m, which is m g over m—so just g...”
Watching them, he felt as if he were looking at gifted elementary schoolers getting their first headache from physics. Everyone reacted the same way. It was the same in middle school, high school, university—even graduate school. If anything, the headaches only got worse with time.
“Anyway, apply concepts like these, run thousands or tens of thousands of repeated experiments, and keep shaving down the error, and what you get is this unit. From now on, every engineer and researcher who learns from me will use these units.”
The three apprentices let out one exclamation after another, mouths hanging open and refusing to close.
“How long are you going to stand there like that? Out.”
“Thank you for teaching us.”
“We’ll come again later!”
“May we also ask about magic formulas?”
“Ask Andersen, the magic advisor, about that.”
He waved them off, and they poured out of the room in a noisy rush. Annoying brats—but they were the talent who would one day support the laboratory, so he couldn’t ignore them. He would have to teach them well.
“I wonder if old man Amos is managing to teach them properly...”
“How many millimeters in a meter?”
“A hundred, was it?”
“You idiot! It’s a thousand! A thousand!”
“Why a thousand? Wasn’t it ten?”
Not the forge, but a large tavern borrowed from Bladewin. Using it as a temporary classroom, with a huge sheet of paper stuck to the wall behind the bar and kitchen, Amos was roaring at the blacksmiths.
“You thick-skulled lot! You can’t even calculate something this simple? One meter is one thousand millimeters! Your heads are nothing but lumps full of piss!”
“Piss...? Well, not piss, but there is some booze in there...”
“Right. Any drinks? Feels weird sitting here without a drink.”
“Bender! Now that’s a smart man—his head works! We’re confused because we haven’t had any beer!”
Amos pressed a hand to his forehead and squeezed his eyes shut. Most of the blacksmiths here had never once thought of scholarship in their lives, but he had not imagined they would be this ignorant.
I’m going to need a plan.
He sighed and looked around. His eyes fell on the bottles on display. He pulled one from under the cupboard and poured himself a glass.
“Hey! You’re drinking alone and not giving us any?”
“You said drinking makes your head stop working, Amos!”
“Is that allowed?”
At their protests, he ground his teeth.
“You miserable bastards!! Even if I drink this whole bottle myself, my head still works better than yours!!”
He downed the glass in one shot, then jabbed a finger at the units written on the paper and bellowed.
“Here! These! Numbers! You! Morons! Who can’t even! Tell them apart! Properly! Listen up!!”
He refilled the glass and went on.
“Anyone who can tell me how many millimeters are in one kilometer gets a free drink.”
“What?”
“For real?”
“Me! Me! I know!”
“What would a goblin-brained fool like you know? I know!”
The blacksmiths’ enthusiasm flared hot in an instant. Amos snorted a laugh and pointed at one of them.
“One centimeter is ten millimeters, and one meter is a hundred centimeters, so...”
He folded his fingers this way and that, calculating.
“A hundred! A million!”
“Correct. Take it, Bender.”
Delighted, the man sprang to his feet, snatched the drink, and took a long swallow.
“Aah! That’s the stuff!”
His juicy reaction lit a fire in the blacksmiths’ eyes.
“Next! Next question!”
“I can get it too! Come on, Amos!”
“Can we keep answering? Amos?”
“Of course you can.”
“You damn Bender! You already had one—stop hogging them!”
“I’ll get the next one myself before he does, no matter what!”
Amos’s strategy of using booze as bait had landed perfectly.
They have to learn this properly if they’re going to handle Robon’s work...
Everyone had more or less learned how to use the milling machine by now. Thanks to that, their work speed had multiplied several times over—but precision work still produced a lot of mistakes. It was no exaggeration to say that this single concept of units Robon had introduced had vaulted the Bladewin blacksmiths’ craftsmanship up several flights of stairs in one go.
Honestly... he keeps inventing things I could never have imagined.
Once, he had cared about nothing beyond smithing itself—but lately he found this work rather fun as well. Call it the pleasure of watching a city change day by day. The quality of their equipment had already become so overwhelmingly good that Iron Hall left every other place in the dust.
“What’s three hundred millimeters plus five centimeters, in centimeters?”
“Me! Me! Eight centimeters!! I got it, right? Right? Kahahaha!”
“You absolute halfwit. That’s the length of your cock.”
“What kind of crap is that? You even look at mine? Huh?”
“Eighty centimeters! How do you not get that? Shit-for-brains.”
“You idiots! How in hell is that eighty centimeters?!”
Amos pressed his temples hard. Watching them spout nonsense to the bitter end, he almost wished he could just swing a hammer all day—it would have been easier on the nerves.
Several days had passed since the Raven Merchant Guild’s departure.
Creeeak—
In Robon’s hand, as he entered the Development Research Department head’s office, was something long and black.
“That? The thing you’ve been working so hard on lately?”
Lately he had shut himself in his own lab, never saying a word about what he was making, just preparing alone with furious focus—and now he had shown up grinning with that thing in hand.
“That’s right. It took a little longer than I expected. Adjusting the weight of the eccentric wheel was harder than I thought.”
Andersen had no idea what that meant, but he nodded anyway. The laboratory director had built something and come out with it, so whatever it was, there had been results.
These days there was so much work that he never had time to build anything together with the director. That only made him more curious about what Robon had been so determined to create.
“Curious?”
“Of course I am.”
A black cylindrical body bent at a right angle from the handle, with something cone-shaped fixed at the end.
“You’ve been saying your shoulders are stiff every day and asking for rubs, haven’t you?”
“It’s fine. Everyone has that sort of thing.”
Robon shook his head.
“No, not everyone. Everyone just happens to be broken the same way.”
The corner of his mouth lifted as he plugged a long cord into the wall outlet.
“W-what are you intending to do...?”
A pointless unease made Andersen flinch. Robon approached carrying a weapon as thick as his own forearm.
“Come on—turn around. I’ll give you a taste of heaven.”
“...Are you sure this is all right?”
“You don’t trust me?”
At that, Andersen swallowed a low sound and turned his back. A cold sensation touched the place where his left shoulder met his neck.
And then—
“Starting now?”
Click.
With the sound of the button being pressed—
VRRRRRRRRRRRRRRR!!
“Ugh... uh-uh-uh-uh-uh...!”
Something hammered a single spot at tremendous speed. His whole body shook with it, and his voice trembled too.
“Th-th-th-this i-i-i-is...”
What had felt faintly painful at first gradually settled—and then—
What... is this?
The hard knots that had tormented him every day loosened, and at the same time an indescribable pleasure climbed his spine and seeped into his head.
“Aaaah...!”
“How is it? Feels good, right?”
A sensation he could not put into words. Yes—good. That word fit perfectly. As the pain vanished and his body eased, it felt as if the heat in him were cooling away.
He closed his eyes slowly and savored the feeling.
“More... more...”