Although it was an experimental ship, the one Jin worked on could be called a small prototype.

"Wow!　This is comfortable!"

Marcia is moving smoothly in and out of the Ermee River.

"Oh, it seems to be very stable.

Rodrigo is also looking on with satisfaction.

Jin looks at the three separate hulls, which seems to be working in the right direction.

With one hull in the front and two in the back, the boat is more stable going up the river, facing toward the bow, considering the resistance of the water.

This is not so much of a problem when going down the river, since the relative speed of the boat to the water is small.

"I think we should build a bigger rudder."

While going up and down the river at different speeds, Marcia picks out areas for improvement.

"I think it would also be better if it could turn in small circles. ......"

Marcia thinks that it would be easier to change direction in a narrow river.

The finished product would be a bit larger, so it would be even better.

There were a few other minor improvements, but these two seemed to be the major ones.

"Wow, that looks fun!

Seeing Marcia, the youngest ...... (10 to 15 years old)... ... the girls of Kaina village were envious of her.

(Come to think of it, Kaina Village has no boats, though they sometimes use golem horses on land and airships in the sky...)

Seeing the girls staring at the ship, Jin also seemed to have his own thoughts.

* * * * * * * * * * * *

"So, I would like to place an order with Marcia's workshop as well.

Just before lunchtime, once Marcia came up from the experimental ship, Hitoshi said, "What do you mean?

"I don't know what's the reason, but I'll do it.

Marcia accepted the offer. Since the boats were to be used on the same river, we could save a lot of time and effort by building them all at once.

And above all, it is a request from Jin.

And even more so when she hears that the girls in the village of Kaina want to sail on it.

"I want more people to know how fun boats can be!"

Marcia laughed.

She smiled at me,

"You really love boats, don't you?

Tiberio said.

"That's true, I've been sailing since I was a little girl.

Tiberio looked at her with narrowed eyes as if he was seeing something dazzling.

"Well, let's have lunch here."

It was around 11:30 in the morning and Jin called out to the others that they must be getting hungry since they had been moving around since this morning.

He was right, and no one objected.

"Oh!　What is this?

Tiberio was the one who was raising his voice with interest.

"It's a dumpling," Jin answered.

Jin answered. The director used to make it for me when I was in the facility.

It was a mixture of half strong flour and half weak flour, kneaded with water, torn into pieces by hand, and boiled in a clear soup.

It was a simple dish with only a green onion as an ingredient, but the current version is based on it, but with a twist.

The current version is based on it, but with a twist. It has a slightly higher percentage of flour to make it softer. However, if it is overcooked, it will fall apart, so it is important to be careful.

The soup is also made from dashi broth, and is filled with wild vegetables from around the village of Kaina, in addition to sharoto (leeks).

"This is delicious!　It has an unusual texture.

Tiberio liked it.

"Is this the second time you've eaten this?　It's delicious!

Tiberio had served it to Marcia in Horai Island before, and it had been so well received that it had been added to the menu this time.

Yes, it is easier to eat than that time.

The more flour you use, the harder it is to break down, but it also makes it chewier. Many people feel the dough is a little hard when they tear it by hand, even if it is as thick as udon noodles.

"Yes, it's delicious.

It is a nostalgic taste with a twist, and Jin is satisfied with the taste.

"Father, can I have another one?"

"Yes, please."

The soup in the one for Jin is sometimes slightly cooled. Reiko, who knew Jin's tastes well, was very considerate in this respect.

* * * * * * * * * * * * * * * * *

"Well, let's see what we can do to improve it.

Marcia said as soon as she finished eating her sudon and after-meal tea was served. She is a workaholic.

"Well, let's take a little more rest first.

Jin puts himself on the back burner and admonishes Marcia. He seems to be able to see other people.

"Ugh, okay."

"......You really like shipbuilding, don't you, Marcia? ......"

"Ha-ha-ha."

"Well then, since we're here, let's hear some of your ship-related knowledge, shall we?"

As soon as Jin started smiling, Marcia naturally took him up on the offer with lightning speed.

"Yes, by all means!"

Rodrigo too,

"I'm looking forward to hearing about the Magecraft Meister, Jin-dono.

Rodrigo showed an expectant look on his face. Tiberio, needless to say, was looking forward to it.

"I don't want ...... to get my hopes up too high," he said.

Jin then began to speak.

"Why do ships float on water?

Jin began to talk about <>. Rodrigo, who did not know much about it, listened attentively.

An object in water becomes lighter by the amount of water pushed out of it. So the weight of the same volume of water as the part of the boat that is submerged in water is equal to the weight of the boat.

"Heh, ......."

"The same can be said for the <. < or . If those air sacs were empty, they would float because they would be lighter than the weight of the air that would fill them."

"I see."

But then the air sacs would collapse under the pressure, so the next best thing is to fill them with helium, which is a lighter gas than air," says Jin.

"...... Well, let's get back to the ship. The weight of an object divided by its volume, or weight per unit volume, is called , and the specific gravity of water is 1 as a standard. If the weight of the ship is divided by the volume and it is less than 1, the ship floats on water, and if it is greater than 1, the ship sinks.

"I see what you mean."

Tiberio shook his head repeatedly.

"By the way, you can find out the volume of an object that is difficult to calculate by submerging it in a container full of water and checking the volume of the overflowing water.

By finding the volume in this way and weighing it, the specific gravity can be determined by calculation.

This is how Archimedes, an ancient Greek, found out whether the crown was made of pure gold or alloy.

"That's interesting, isn't it?"

Jin did not mention the names of ancient Greece or Archimedes in his explanation, but the response was unexpectedly favorable.

"Please let me hear from you again.

After the lunch break was taken, it was time to start the discussion.