By the morning of the 18th, Jin and Elsa were being run off their feet.
The culprit? The endless line of nobles and influential figures clamoring for their time.
It seemed everyone wanted a connection to the "Lord of Kunlun," even if it was as thin as a spider’s silk, and they had been arriving incessantly since dawn.
Eventually, Jin and Elsa used the excuse of a restroom break to slip away. They headed to the emergency transporter, moved to the Konron 3, and then transitioned to Hourai Island. There, they swapped places with their Doppels.
"Whew, finally, some peace."
"…Agreed."
Back on Hourai Island, the two of them slumped into chairs, completely spent. They had only been at it for about an hour, but the mental strain was nearly unbearable.
Worse yet, they had only made it through a third of the visitors.
If they had been forced to endure that for another two hours, they might not have recovered.
"I feel bad for Laojun, but let's leave the rest to him."
"…Mm."
In fact, considering the need to record the faces and temperaments of every noble, leaving it to Laojun was likely more beneficial for the future anyway.
"Father, would you like something to drink?"
Seeing the two of them so worn out, Reiko spoke up.
"Ah, yeah. Some green tea would be nice…"
"Understood."
While tea plants had been cultivated on Hourai Island, it would likely be another year before they could harvest any leaves. Consequently, the tea they were currently drinking had been purchased from the Shouro Empire.
"Ah, the aroma is wonderful."
Since it was sencha, the ideal brewing temperature was around 80°C. Jin, who possessed a sensitive "cat's tongue" when it came to heat, sipped it slowly as it cooled.
"Jin-nii, that reminds me."
Elsa spoke up while enjoying her tea.
"What would happen if free ether vanished completely?"
Perhaps she was thinking about the conditions in the southern regions.
"Magic tools would become useless. It would be just like being hit by a Magi-Jammer."
"True."
"As for humans, since the mana inside our bodies never drops to zero, I think it would just result in a slightly suffocating sensation."
It would be similar to when the demon race entered a region with low free ether.
Furthermore, the giant golem—an artifact of the Shouro Empire—had been sealed underground in a facility where the concentration of free ether was reduced to nearly zero. Considering that humans had entered that area and suffered no ill effects beyond being unable to use magic, the impact on the human body was likely minor.
"…In that case, shouldn't we develop power sources that don't rely on magic?"
As a contingency measure, that is.
"Good point. If we did that…"
Several power sources came to mind, but Jin figured electricity would probably be the most versatile.
"Batteries, huh…"
He knew the principles behind motors well enough to build one, but batteries were another story.
"…I don't know enough about the chemistry."
At most, Jin felt capable of creating rudimentary cells by dipping different metals into an electrolyte.
"…Hmm…"
For the time being, Jin decided to try his hand at a motor.
The most difficult part appeared to be the windings. He would need to apply a heat-resistant, insulating coating to copper wire.
"…I suppose I'll use urushi."
Jin decided to use copper wire coated in urushi, which he then cured and seared at high temperatures.
"The armature should be silicon steel, if I recall."
He made good progress there, but then he hit a snag.
"…Powerful permanent magnets are going to be a problem…"
Even though he knew names like ferrite, neodymium, and samarium cobalt, even Jin didn't know the exact manufacturing processes for them.
"That’s an unexpected pitfall."
Jin felt a bit dejected as he realized the limits of his knowledge.
"…Ji-Jin-nii, I'm… sorry?"
Elsa, for her part, grew a bit flustered, worried that she had accidentally upset him by prompting the idea.
"…But really, without magic, scientific civilization truly has to start over from square one."
It was a late realization, but Jin once again felt the immense blessings of magic in this world.
"For now, I'll just make the field an electromagnet too…"
Jin set about trying to construct at least the motor itself.
Two hours passed. In the Kingdom of Egerea, the Doppels had finished their social duties and were finally relaxing.
Meanwhile, Jin:
"Alright, it's done."
After three prototypes, he had completed Practical Motor No. 1.
It was a cylinder 30 centimeters in diameter and 30 centimeters long, with a 10-millimeter shaft.
"…But I don't have a power source."
Jin gave a wry smile at his own lack of foresight.
"Is lightning-attribute magic no good?" Elsa asked.
"Well… the voltage is too high, and it can't flow continuously for a long time, so… yeah…"
Jin tried fiddling with a magi-formula to see how much he could step down the voltage. The problem was that if he lowered the voltage too much, the discharge would stop entirely.
"Hmm…"
Jin had been groaning in thought for a while now, though his expression suggested he was actually having fun.
"I’ve got it! How about an Induction Radiator?"
It was a weapon that used the principle of electromagnetic induction to generate induced power in metal to heat it.
"If I drop the frequency, it probably won't radiate, but it will generate voltage. It might work as a generator."
"But Jin-nii, wouldn't that just mean you're relying on magic again?"
"Ah, right…"
It was a persistent dilemma.
Even in his old world, "storing electricity" was a challenge. Dry cells and storage batteries didn't actually store electricity; they used chemical reactions to generate it on demand. Capacitors stored actual electricity, but not in amounts that could be considered practical for power.
"Hmm… maybe I should change my approach."
After much agonizing, Jin decided to move away from motors for a moment.
He decided to reconsider purely scientific power sources—systems where he could use magic to create the device, but where its operation was purely mechanical.
"Like spinning a turbine with compressed air."
If he used an adamantite cylinder, he could compress air to tens of thousands of atmospheres, which might be practical. Since there were even engines on Earth that ran on CO2 canisters, he might be able to replicate something similar.
"Oh, and there are flywheels, too."
That was a method of storing kinetic energy by rotating a heavy disc at high speeds. This also seemed feasible if he used adamantite.
"I could simply use a boiler to create steam and spin a turbine, but… that feels a bit too primitive now."
Without the shortcut of magic, Jin realized once again how difficult it was to replicate Earth's technological path.
However, while he was preoccupied with his experiments, time had marched on, and the banquet had begun in the Kingdom of Egerea.
Noticing the time, Jin and Elsa sighed.
"…Ah… maybe we should just stay here?"
They initially considered leaving the rest of the evening to the Doppels, but then:
"But still… it would be a bit much to skip out entirely."
"Mm, you might be right."
Changing their minds, they headed off to the "exhaustion" reception.