The livestock pens in Village One, Village Two, and Village Three were recently expanded. This was because the animals born in each village had reached a certain size.
Due to its small population, Village One only kept pigs and chickens. In Village Two and Village Three, they raised cows, pigs, goats, sheep, and chickens. Plans were also underway to introduce livestock to Village Four—the Sun Castle—but progress had stalled because none of the residents knew how to care for them. Currently, several members of the Devil Race were preparing to migrate to the Village of the Great Tree to undergo training in animal husbandry.
"Since we have so few cows and horses, we’ll need to source breeding stock from the outside," someone noted.
In typical villages, people apparently traveled to other settlements to either borrow breeding stock or bring their animals to be sired.
"Traveling like that sounds like a massive hassle," I muttered.
I wondered if I should just buy more through Michael-san. It would still be a difficult transport, but at least it wouldn't involve a round trip, which made it the better option. I’d have to wait for a time when Hakuren or Rusty were available to help.
Moving livestock by balloon, however... that would be far too dangerous if they started to panic.
Speaking of the balloon, Zabuton finished the envelope in record time. We now had a craft large enough to carry four adults. It was a hot-air balloon that stayed aloft by using a magic tool to heat the air inside the sphere.
The design was a simple, classic orb. We could control the vertical movement easily enough by adjusting the magic tool's output. Steering, however, remained a problem. At the moment, we were entirely at the mercy of the wind. Unless we kept it tethered to the ground with the high-strength ropes Zabuton had woven, there was no telling where it might drift.
Was it impossible to steer a balloon?
Probably. After all, if you added an engine and a rudder to a balloon for the sake of navigation, you ended up with an airship. As it stood, the balloon was useless as a reliable means of reaching the Sun Castle.
How did I not realize this during the prototyping phase?!
No, I couldn't give up yet. I just had to figure out how to make this thing go where I wanted.
...Actually, turning it into an airship by adding power and a rudder really was the best solution.
Would a magic tool work as the power source? Using one to spin a propeller for thrust seemed like the most logical path. I crafted a prototype propeller and took it to Lu for a consultation.
"A device that creates wind by spinning this? I think I can manage that... but are you planning to move the balloon by blowing wind at it?"
"Eh? No, I’m going to attach it to the basket where the passengers sit."
"?"
Lu looked at me with pure skepticism. Eventually, she produced a magic tool that functioned like a prototype fan, and we began our experiments. When we set it on the floor, it simply blew air. But when we mounted it onto a wagon with wheels...
"The wagon... it's moving!" Lu cried out in shock.
It was just basic action and reaction. I figured it was something people experienced in their daily lives, but apparently not here. Lu immediately summoned Flora and Tia to show them the fan-propelled wagon.
"What? What kind of magic is this?"
"Is it a prank by a wind spirit?"
...I could excuse Flora's confusion, but shouldn't Tia know better? She actually flew, for goodness' sake. This was the most basic of principles. She used her wings, right?
"My wings are for manipulating magic power," Tia explained. "I don't actually flap them like a bird to stay aloft."
I see. Perhaps because magic was so highly developed in this world, physical science had been neglected. It was my turn to be surprised when they were baffled by a fan on a cart.
"But you understood the principle of the hot-air balloon, right?" I asked.
"Well, it's obvious that warm air rises," Flora replied.
"That's a fundamental of magicology," Tia added. "Though I never imagined it could be used to lift objects like that."
It wasn't that they lacked scientific understanding; it was more that their knowledge was specialized in different directions.
"Attention, everyone. Press your palms and fingers together perfectly... now, fold your middle fingers inward so the knuckles are touching. Try to sandwich a copper coin between your ring fingers. Now, try to move just your ring fingers to drop the coin."
"That sounds easy... wait, what?"
"Huh? Why won't they move?"
"M-my fingers are stuck!"
I see. They were physically "weak" in this area too. It was a little endearing to watch them struggle.
"Is this magic?"
"No, is it some kind of hypnosis?"
"It feels like my body isn't my own!"
"Don't strain yourselves," I laughed. "It's just physically difficult to move your ring fingers outward when your middle fingers are tucked in like that."
In the end, Lu agreed to handle the magic tools for the propellers. With those, we wouldn't be entirely dependent on the wind anymore. As for steering, a rudder would have been ideal, but I decided to mount two propellers on either side of the basket. By toggling the left and right fans on and off, we could theoretically bank left or right.
Strength? No problem. Weight? By reducing the capacity from four passengers to two, it was manageable.
"Time for a test flight!"
Two Mountain Elves were chosen by lottery from the volunteers. It was time to soar through the great blue yonder!
...But first, safety. I equipped the Mountain Elves with parachutes and had Granmaria and her team fly escort nearby.
"All right! Let's go!"
... ......
Currently, we had a basket suspended beneath a spherical balloon, with a magic tool heating the air. By mounting propellers on the sides of that basket, we had achieved thrust... but it didn't work like the image in my head.
Instead of the whole balloon turning left or right, only the basket tried to surge forward, causing it to tilt at a precarious angle. The balloon itself refused to move with it. Furthermore, because the basket was tilting so sharply, the flames from the heater were dangerously close to scorching the envelope.
"Abort! Bring it down!"
If the horizontal force was only applied to the basket while the upward force was on the balloon, the balance was completely off. Come to think of it, airship propellers are usually attached to the frame of the envelope itself. Trying to "upgrade" a simple balloon was the wrong approach. I had to design it as a proper airship from the ground up.
That meant I would need a frame to mount the propellers onto the envelope. That would increase the weight, which meant the balloon would need to be much larger. But given the limits of the current magic tools to heat that much air... it was looking grim.
Back on Earth, airships weren't hot-air balloons; they used gas for buoyancy. Helium, if I recalled correctly. I had no idea how to manufacture that. Then there was hydrogen... but no, absolutely not. That would just be a flying bomb. It was too dangerous.
In that case, I either had to find an incredibly lightweight material for the frame or find a magical substitute for helium.
"I'm afraid we'll have to suspend development on the airship for now."
It was a disappointment.
"Don't cry, you two," I said to the Mountain Elves. "I'm frustrated too."
We decided to remove the propellers, revert the balloon to a four-seater, and just use it to enjoy the view. If the wind was right, we might even be able to drift as far as Howlin Village or Draim's Nest. It wasn't a total waste.
For the time being, we would still have to rely on those with wings to travel to the Sun Castle.
"Would you like us to guide the balloon from our end?" asked Gou from the Sun Castle.
Apparently, if we flew to a certain altitude, the Sun Castle could "pull" the balloon toward it using its own power.
"I-I see. If getting there is possible, what about the return trip?"
"That is also fine. We can guide you until you are directly above the village."
...Well, if he was that confident, I supposed we could give it a try.
And just like that, we drifted lazily to the Sun Castle... and drifted lazily back to the Village of the Great Tree. We had established a transport route.
I looked into the eyes of the Mountain Elves standing beside me.
"We are definitely finishing that airship one day."
"Yes, Village Head!"
I nodded firmly. But for the immediate future, we would focus on mass-producing the basic balloons. We needed at least three, including spares. Ideally five.
It was time to get back to work.