After building a reservoir and installing a sluice gate, Jin excavated toward the water vein.

"<><>"

Jin reinforced the hole at the same time.

"Oh?

（It worked.)

In fact, what Jin dug out this time was a water vein that was under <>.

There are several underground water veins that flow from Lake Kotsushi, and the water veins that originally existed in ......<> before the work of ......<> are pressured enough to flow out like this. The water is flowing deep under the ground.

The water veins run deep underground and can only be excavated with Jin-level technology and knowledge.

Due to the amount of water flowing through the water vein, Jin decided to excavate the reservoir because it was expected to receive < this time and the annual rainfall was expected to increase.

Jin and Lao-kun think that if they increase the number of reservoirs in the future, they will not be able to use only this kind of self-flowing water veins, and they will have to use automatic pumps in that case.

(But for the time being, we can use self-flowing water here.)

The volume of water coming out of the reservoir is not too much or too little, about 1,000 liters (1 cubic meter) per minute.

The capacity of the reservoir is 1350 cubic meters. In other words, it takes 1350 minutes = 22.5 hours to fill the reservoir.

This is almost one day, which is enough for Jin D. First, we headed for the village to the waterway.

First, a channel is dug toward the village and a small reservoir is built separately.

From there, the channel is extended in three directions, and another small reservoir is constructed at the end of the channel.

The reservoir at the end of the channel is the irrigation pond.

Jin D finished these works in the morning with the help of Reiko and Hope.

"That's it."

The reservoir is still far from full.

"Now we just have to make sure it doesn't overflow in case it does."

It is less than 30 kilometers from Saich village to the sea.

Jin D decided to build a drainage channel to the sea.

For this, he decides to use a .

He calls 10 from Penglai Island, under the pretense that they have been loaded onto the in advance.

They choose a place where there are no fields or orchards and dig a trench. The ditch is 2 meters wide and 1 meter deep.

< is 10 meters per minute.

A 30 km channel will be completed in 50 hours ......2 and a little over a day.

"......"

"............"

The village head and the vice-minister of technology were speechless not only at Jin, but also at the outstandardness of the golems they were using.

* * * *

After a light lunch as a pause, Jin D. set about his next task.

The next task was to install an incinerator.

Most of the garbage could be composted, but the soil in this area is fertile enough that it is not really necessary.

Rather, it is more important to prevent the filthy garbage from becoming a breeding ground for molds and pathogens.

Eventually, Jin hopes to be able to incinerate the sludge that accumulates in the sedimentation ponds of the drainage canals.

"I think metal is the way to go."

He is a little concerned about using stone, as some materials must be incinerated at high temperatures.

In the case of rocks, which are mixtures of several types of mineral particles, exposure to high temperatures can cause the heat-sensitive minerals to fracture and the bonds between the particles to break down, making them brittle.

Granite, which is made of quartz, mica, and feldspar, cracks at about 500 degrees Celsius.

Marble is also said to powderize at about 800 degrees Celsius, and about 1000 degrees Celsius seems to be the upper limit for refractory stones. The upper limit for refractory stones is around 1000 degrees Celsius.

Many synthetic and sintered fine ceramics are resistant to heat.

Alumina (aluminum oxide) can be used up to about 2000 degrees Celsius.

The disadvantage of ceramics, however, is that they are hard but brittle, making them unsuitable for rough handling.

Jin therefore decided to use iron, which has a melting point of 1538 degrees Celsius, and to strengthen its molecular structure by applying toughening and stabilizing agents to it, so to speak. I thought of using <>, which has a reinforced molecular structure.

"Roughly, can it withstand up to ......3000 degrees?"

Jin has seriously processed it so that it has such physical properties.

Along with the improvement in heat resistance, the strength is also about twice that of the original steel, so it will not be damaged in daily handling.

The height including the chimney is 3 meters. The main body is 1.5 meters high, 1 meter wide, and 1 meter deep.

In appearance, it does not look much different from metal incinerators seen in Japan today.

However, it has been designed to be maintenance-free.

The incinerator is designed so that it will not break down if used incorrectly, even if there is no one around to fix it.

"Please burn the garbage you don't need with this."

Incidentally, the incinerator is equipped with a heating device that uses fire-attribute magi crystals, so it does not need fuel.

Furthermore, it determines the optimum temperature for burning the garbage placed in the incinerator, so that there will be almost no unburnt residue.

We would have liked to be able to use the heat from the incineration process to boil water, but we decided not to do so.

"...... and so on. Please try using it in various ways."

"......"

"............"

When this was explained to them, the village chief and the technical vice minister were again at a loss for words.

* * * *

The explanation of how to use the incinerator was over, but it was only 2:00 p.m. The time was not yet 2:00 p.m.

"......I knew it, let's build a hot spring ...... no, let's build a public bathhouse."

Jin D. could not help taking a bath (the dirt would come off), but Jin himself, who was now in control of the ship, wanted to build a bath.

Incidentally, due to the chronic shortage of water in the four duchies, there is no custom of using public baths except for the areas near Lake Kotsi and Lake Yato.

The nobles barely soak themselves in hot water once every few days.

The common people wipe their bodies with water even in winter (although the lowest temperature rarely falls below 20 degrees Celsius).

In the past, when it was dry, but now, as precipitation increases and humidity rises, the demand for baths is expected to increase.

This is why Jin decided to build a public bathhouse as a model district.

Keeping the body clean is useful for maintaining health and preventing diseases.

"Should the bathtubs be of the magic circle type?

The low cost of the bathtubs makes them convenient for widespread use.

Like a reservoir, it heats groundwater that flows out of the ground, and the water is poured over it.

"It might be a good idea to have it blow out from the bottom instead of pouring it in from the top."

The advantage is that waste is less likely to accumulate.

"The wastewater should be connected to the drainage system via a septic tank.

We decided to install a magic circle type purifier for the septic tank as well.

Even though it is a magic circle type, it is engraved on a bronze plate and sealed with quartz glass, so it is not susceptible to deterioration over time.

Jin and the old man estimate that it will operate for about 50 years.

It is enough to keep the bathtub heated all the time and to pour the water over the bathtub, as in this bathhouse.

As for the changing rooms, it will be decided the next day for reasons of materials.

"Now you can take a bath every day."

"Oh!　This is wonderful!

Village head Ike was overjoyed, and Nahams Marrow, the Undersecretary of Technology, looked at the bathtub,

"...... Jin-dono, can this be mass-produced?"

He looked as if he wanted the capital city of Raisonnale to make one as well.