Death March kara Hajimaru Isekai Kyusoukyoku Book 9 - 9-7. Highway of Weeds

9-7. Highway of Weeds
Satou's here. I liked science experiments during my primary and middle school days. Among them, I was really thrilled with electrolysis that separates oxygen and hydrogen. I feel that making up magic tools bring the same kind of excitement as these days.
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Not less than half a day after we've passed through the farthest village with population of 200 people, the road begins to be overgrown with weeds and can't be seen.
"The road's condition is just like we've heard isn't it. Are we really going to advance on this road?"
"Yeah, let's cut it for now."
"Leave it to me~" "I'll work hard nodesu!"
I got off the wagon while saying so, Pochi and Tama chased after me after taking grass sickles from the toolbox in the wagon. After posing as if 'clink'-like sfx written on the background, they begin to push their way through the thickets.
No, you girls, I'm going to use magic here?
Since the two are so eager while looking like they're having so much fun, I can't bring myself to stop them. I guess I'll wait until they're tired.
"Master, permission to participate the strategy meeting. Reporting for a different style of grass cutting."
I don't know if the figures of Tama and Pochi cutting the weeds touched Nana's heartstrings or something, but I took out a long grass sickle and pass it to her.
"Master, it looks like the three are motivated to cut the weeds with the sickles, but we don't know how long until we arrive to the base of the mountain. How about we hire the people from the village earlier to cut through it, or spread oil and burn the weeds?"
"It'll be bad if it turns into forest fire, so the burning is forbidden. I'll cut them with magic after Pochi and the others are tired."
That reminds me, I heard that Mia created road in the forest during their way to Muno city back then, but when I asked her, she replied, "Impossible". She can probably only use it for a short course.
Since there are ingredients for medicines and cuisines mixed among the weeds, I leave Arisa and Mia to gather them. I ask Lulu and Liza to prepare for lunch.
"I wonder what~ is that?"
"Hmm? It's a kiln."
Since I saw characters in the manga I had read a long time ago baked pizza with a kiln, I made this one by using earth and fire magic. I must say that I've done a good job for an improvised thing. Even though it's simple, to be able to make it faster than making a cup ramen is too wonderful.
While having a sidelong glance to Arisa who's fallen to the ground with a dry smile, I take out the pizza dough that I've left fermenting in the Item Box.
I take out the tomato sauce I've made in Puta city and spread it on the pizza dough. As for the toppings, there are cheese of course, and also bacon and salami that are standard for pizza, I've also another type of pizza with lots of vegetables like sliced tomato, asparagus, eggplant, and paprika.
Since the pizza dough is thin, seem that it won't be enough to satisfy the appetites of hara heri girls. I guess I'll make some cube steak and french fries as the side menu.
"It stretches~?" "Hot hot, nanodesu."
"Uwa wa, stupid good~"
"Nn, delicious."
The juvenile troupe are awfully excited, looks like they like the pizza. Pochi and Tama get sticky from the dripping cheeses, they have to wash their faces later.
Lulu and Nana seem to like it too, but not to the degree like the four. After eating one slice of the pizza, Liza sets her sight to the unmarked cube steak. She's really unwavering.
I'm glad that they're eating it happily, but I stop Arisa who looks like she'd eat too much. She looks at me reproachfully, but she seems to understand after I explain about the dreadfulness of rebound. The diet back then was hard after all.
That's why Arisa. Please stop looking like that at Pochi and the others eating pizza.
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Since Pochi and the others are satisfied, I decide to open the path with magic from the afternoon.
First, I fire [Air Blade] that follows close to the surface of the ground along the road.
The wind released from the short wand cuts the weeds while leaving 10 centimeters of it above the ground. The wind continues on while cutting some slightly elevated grounds, and bushes along the way. In the end, it finally stops 200 meters ahead on a small five meters tall cliff.
"You, you really should learn to stop overdoing it."
"Nn, destruction of nature."
Was it too shocking, Arisa grumbled with more unreserved tone than usual. Is it because you're scolding me that Liza is taking regretful pose.
The fact that the trees along the road are cut is within my expectation, but for even the cliff to be cut in two and crumbles is beyond my expectation.
If we advance just like this, the horses can sprain their legs from the unseen ramp, and soft grounds, so I decide to prepare the soil with earth magic.
This time I'm not using [Wall], but the very thing itself, that is [Flat Land] magic. Seems it's a magic that's used frequently by not only the army, but also the general populace. It was a magic from the scroll that I had bought from the firs magic shop I visited in the duchy capital, but I didn't have opportunity to use it until now.
I set the range to be the course of the road and exercise the magic. Since the ground is covered by weeds, I don't know if the soil really has been prepared, so I check the terrain on the map. Looks like it's been leveled without problem.
Since the cut weeds are hindering the horses feet, the wagon isn't speeding up. The wheels are also looking like they'll slide. I instruct the wagon to running slowly at only several kilometers per hours speed, we're going while opening the path anyway.
I'm leading while using magic, and Pochi and Tama who are walking while picking up herbs and medicinal plants from the cut weeds. Liza and Nana are removing bushes and fallen trees that are out of bounds from the road. Arisa and Mia are sorting the gathered materials.
However, it'll inevitably take some time. Naturally, the road to the mountain range is not just extending straight, and not flat as there are undulations too. Particularly, the road goes around hills, low-laying mountains, and valleys.
Since I don't have any other good plan, we're advancing on while opening the highway, and I decide to camp on the bank of the streamlet 10 kilometers ahead.
Although there are around 20 demi-goblins 1 kilometers away from the planned camping ground, they seem to have become frightened by the sound of vegetations cutting and ran away very fast. It's going to be safe tonight.
I left the dinner preparation to Lulu and went back to the place where I started to clear the path, I put a rough 100 meters wide mud wall [Wall] there. With this, there won't be strange rumor about the road that suddenly appears.
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That night, I've assembled an aerodynamic engine that's been half completed.
However, the control is difficult.
After it was finished, it did float when I tried to put mana into it little by little, but it was bad after that.
After the engine fed on a certain amount of mana, it rotates down to the ground with a plop, and then it powerfully plunges to the nearby tree.
Apparently, the fins that are composed on the aerodynamic engine each has its own fixed output on top of having the so-called power band. Due to that, you can't just pour mana into like normal magic tools as it will rotate off-balance and accelerate suddenly.
Looks like it needs a control circuit for tuning the output, but there's nothing about that in the documents I have at hand. There isn't also anything about how the control of aerodynamic engine is difficult written in the documents, don't tell me that the author of this document actually hasn't assembled the engine himself.
"Or maybe the control itself isn't something that's impossible to do?"
Although the frame of the engine that has hit the trees and the shrubs are broken, the fins and the magic circuit themselves are fine, so I'm going to challenge it again. I can more or less make the aerodynamic engine floats for about 30 seconds, but since I have to concentrate on it all the time, it's too bothersome. If it's like this, even lifting the wagon with [Magic Hand] is better.
I'm searching for any other hints until late at night.
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The following day, we're going to travel by air.
Of course it's not like I've found some breakthrough way to control the aerodynamic engine.
I've just switched my way of thinking--that's a bit presumptuous.
If it can't be done with magic, then I can just make use of science!
I've only noticed that.
I've become too reliant with magic just because I'm able to create some magic tools. I'm just going to make normal balloons and use them to travel in the air.
Although it was hard after I got the idea.
At first I wanted to make hot-air balloons, but when I thought about the number of the people and the horses, I abandoned the idea. It's a bit too heavy.
Therefore I decided to fill it with light gas like blimps.
The problem is the material for the balloon. When I was doing the preliminary calculation, it seemed that it was necessary to make an ark big enough to carry people and horses in the air.
I search through the storage, and the parts from the parasites of the great monstrous fish seem usable. The specimen that stole life until it became level 50 had particularly grown quite big, so I'm going to use it.
Since there wasn't place that was convenient enough, I flew back to the open space in the underground labyrinth at the duchy capital. The place is not the one I usually use, but on the lower floor that's half submerged in water.
I've decided to make the balloon for the blimp, and the hydrogen for the buoyancy here.
I successfully made the balloons from the parts of the parasites, but I couldn't make something too big, only ones with just enough length. Thus, I decided to make small balloons with one meter diameter and stuff them into a big web.
To create the hydrogen, I make use of [Pure Water], [Discharge], and [] magic. Since I use [Air Control] to prevent the separated gas from mixing, it's progressing relatively well.
I might as well store the oxygen I've separated into different balloons.
I made a mistake during the operation once and the balloon exploded, but since I immediately deployed [Air Shield] at once, there wasn't any victim like burning clothes, although I was a bit surprised. I'm glad that it's a sturdy labyrinth. It's worth the trouble of going far.
Since the force of hydrogen explosion was greater than I expected, I combined the hide of the great monstrous fish and armored newt's bones to make fire and blast proof ceiling on the ark. The hide of the great monstrous fish are something that I've taken when I was cutting the meat. Since the hypodermis is thick, I only use the epidermis this time.
I make another hydrogen balloon explode as a test, looks like it can defend against it without problem.
I go back to the place where I experiment with the aerodynamic engine, place the ark on the trees around the area, and attach the balloons on it.
I go toward the camping ground while imagining everyone's face when they see the airship.