Chapter 31

After returning to the palace, I immediately got back to my official duties.

Due to the Shriggan boot camp, I haven't felt like I've enjoyed my summer vacation at all, what with all the swimming, horseback riding, archery, and swordsmanship. But I guess it was a good experience, considering the vast and majestic Wylde Viscountcy, where all these activities took place. If we were to do this at the palace, we would have to do them with the knights on the riding grounds and archery fields.

During the breaks from training, Jack, Silfa, and I would have tea and picnics together, and we've become really close friends. I think we can even call each other best friends.

According to Serea, Jack has changed dramatically. He used to act like a game character, being arrogant, pretentious, and bossy, while also struggling with his complexes and showing no disrespect to Silfa. She says he's changed so much that it's surprising.

When we're not around, they get all lovey-dovey, which is kind of annoying.

"It's all thanks to you, Shin-sama. You set a good example," Serea says, but I think it's just that they got envious of us, seeing how close we are.

In the capital, there has been a heatwave every day, and there have been cases of heatstroke at the orphanage and the hospital.

At the hospital, they've been using cold, damp towels, and at the orphanage, they've been using the large bath as a cold bath for the children, so no one has had any serious issues.

At the hospital, they said, "It would be great if we could make ice..."

Since supervising the hospital is also part of our job, this is a problem we need to solve. While there are many ways to boil water or heat things in this world, there is no technology for making ice. I've heard that mages can do it, though.

The advanced country where my sister is married, Halfa, has many excellent mages, which is why it is a strong nation. They can even heal diseases and injuries with magic. Our mid-level nation hasn't established such a system yet.

There are many people with high fevers due to colds and epidemics, and it's known that cooling can help with bruises and burns, but we can't make ice because we don't have mages. I wonder what we can do...

When I returned to the palace and tried to relax in Serea's room, she said, "In my world, we had refrigerators."

"What are those?"

"They're boxes for storing food, and the inside stays cold."

"That's amazing! How do they work?"

"...I know they use electricity to run a motor, but I don't know how they get cold."

Damn! That's a shame! I really want to know how to do that!

Since she doesn't know, she can't remember it. It's a pity.

I don't understand what "electricity" or "motor" means either.

"Do you have pumps in this world?"

"Of course, we do. They're used to draw water. There's even a hand-cranked pump in the kitchen to draw groundwater."

"What about a vacuum pump?"

"What's that?"

"A pump that continuously draws out air."

"If it can draw water, it should be able to draw air too... I don't know if we have one, though."

Serea thinks for a moment.

"I once saw on an educational TV show that if you put water in a container, seal it tightly, and keep removing the air, the water will freeze."

What's a TV?

"Really, water freezes just by removing air?"

"Yes."

"Why?"

"I don't know."

I don't know either. I can't understand it at all.

"...Should we consult someone at the academy?"

"Yes!"

The next day, I visited the academy alone to meet with a physics teacher. Serea couldn't come because she had princess education at the palace.

"There's a man who recently invented an alcohol thermometer."

"An alcohol thermometer?!"

The alcohol we helped mass-produce is being used in unexpected ways...

When I went to see him, a young researcher named Celsius greeted me.

"I was studying the properties of alcohol and noticed that it expands significantly when heated, so I thought about applying it to a thermometer."

He showed me the thermometer.

"I colored the alcohol and sealed it in a glass tube. The alcohol expands when heated and moves up and down the tube to indicate the temperature. We used to use mercury, but it's toxic, so this can measure temperatures from ice water to boiling water."

He demonstrated by boiling water with an alcohol lamp and inserting the thermometer.

"I'm glad you're interested in this kind of research, Your Highness! Do you know that boiling water always has a constant temperature? No matter how strong the fire, the temperature of the water won't rise beyond a certain point."

That's interesting! I didn't know water had such properties.

Now that you mention it, water doesn't get hotter and hotter with a stronger fire; it just turns into steam.

"What about ice water?!"

That's what I really want to know.

"It's summer now, so we don't have ice, but ice water also has a constant temperature. In winter, I can show you with the ice on puddles."

"Actually, I came here to consult about how to make ice."

"Uh... Maybe you should ask a foreign mage?"

Celsius was surprised. It seems the idea of making ice hadn't occurred to him.

"Do you have a vacuum pump?"

"Yes, we do. This thermometer is made by creating a vacuum in the glass tube and drawing up the alcohol."

"That's it! You can use it to make ice!"

"Wh-what!?"

Celsius was surprised.

I saw the vacuum pump.

It's a hand-cranked device where turning the handle moves a piston to create a vacuum in a glass container. This is used to remove air from the thermometer's glass tube and fill it with alcohol.

"If you put water in a vacuum, it should freeze."

"Really? I've never heard of that."

"I haven't seen it either."

"Let's try it!"

We put water in a beaker and placed it in the glass container.

Then, we connected the tube to the vacuum pump, and Celsius started turning the handle.

No matter how much we tried, there was no change.

"Is this... real...?"

Celsius, who was turning the handle, seemed to be getting tired.

"Let me take over."

"But, Your Highness..."

"I suggested it, so it's my responsibility."

"Ha... ha... ha... I'll... call some people. Keep going, keep going."

Several people gathered, and since the prince of this country was turning the handle of the vacuum pump with all his might, everyone was curious.

"Let me take over, Your Highness."

People took turns, and eventually, the water in the beaker started to bubble and boil.

"The water is boiling..."

"What? Why?"

"Why is it boiling without a fire!?"

"Water boils in a vacuum!"

The researchers were all surprised.

"Wait, weren't we trying to make ice? Boiling is not good, right?"

"Is it getting hot?"

"Should we check?"

After some discussion, we all decided to touch the beaker.

Oh no, we had to let air back into the container. We turned the valve, and air rushed in. We lifted the container.

"It's cold..."

I touched the beaker with the water. It was cold!

"What? Why?"

The researchers were all surprised.

This got everyone excited. Scientists are so interesting. We reconnected the tube, sealed the container, and took turns turning the handle. With many people working together, the experiment progressed quickly.

The beaker, which had been bubbling, eventually stopped, and the water became still.

Everyone had taken off their jackets and was working up a sweat while turning the handle and observing. Suddenly, a crack appeared in the beaker.

"What...?"

Everyone was surprised. The beaker had cracked, but the water didn't leak.

"Could it be..."

We let air back into the container and opened it.

We cautiously touched the beaker.

"It's frozen..."

"It's frozen!"

"It's ice!"

"Yayyyyyy!"

It was a big commotion.

"Great discovery!"

"Making ice so easily!"

It wasn't easy. Ten people worked up a sweat turning the handle.

"We'll study this principle! We'll try to scale up the device and see if we can mass-produce ice!"

Celsius shook my hand excitedly.

"Please do. I was thinking about making ice for patients with high fevers at the hospital..."

"We'll do it, we'll do it. We'll deliver it to the hospital first if we succeed!"

It seems promising. I'll leave it to them.

When I returned to the palace, Serea was having afternoon tea after her lesson.

"Serea! We made ice!"

"How did you do it?"

"We used a vacuum pump to remove the air, and the water froze."

"That's great!"

...Her reaction was a bit lukewarm.

"Everyone at the academy was excited about the discovery..."

"What...?"

Serea was surprised by this.

Maybe it's something she's seen before and finds ordinary.

A few days later, we received a message from the academy explaining about evaporation and latent heat, but I didn't understand it.

"When water boils, it turns into steam and releases heat, which is why the temperature doesn't rise further. By removing the air, you force the water to boil. The heat is removed through evaporation, which we call latent heat. When you wipe your skin with alcohol for disinfection, it feels cool, right? It's the same principle."

Is it the same?

I thought I was using the pump to draw out the heat. It seems I was wrong.

In any case, they said they would work with other departments to scale up the device. They plan to use wind power, water power, or the recently developed steam engine powered by coal to create a mass-production device for ice. They asked me to apply for a budget and join the list of researchers.

"I don't think I should be on the list. The idea of water freezing in a vacuum came from my fiancée, Serea, so please put her name on it," I said, and everyone was surprised.

Serea might end up as a co-author on a paper again.

"Look, ice water has a constant temperature regardless of the amount of ice! Temperatures have been inconsistent with thermometers, but I want to set 0°C for ice water and 100°C for boiling water as the standard!"

Celsius showed me a thermometer in a beaker with ice.

We're back to Celsius...

Next time: "31. Congratulations, Shriggan"