112-What descends underground

 Judging by the brightness of the sun rock shining far overhead, it was probably a little past two in the afternoon.
 I spread out a blanket near the safe stairs and decided to have a late lunch.

 I cut a thin slice of sour black bread, cooked it until it was crispy, and put smoked chicken thighs and pickled onions between two slices of bread.
 It is seasoned only with salt and rosemary sprinkled during smoking.
 I also a cup of apple juice mixed with honey, because if I ate it in a hurry, I would surely choke on it.

 I nibbled on the sandwich leisurely next to Yol, Kuu, and Tinya, who were moving their mouths in silence.
 The smoked meat was cut into thick slices, as the gourmets had ordered, and it was very crunchy.
 It was tasty, but my jaw was getting tired.
 Also, the taste is a bit monotonous, so it would be nice if there was a change in the second half.

I'd like some mayonnaise soon. ......

 As I muttered, I took a closer look at the scene in front of me.  
 The 15th floor can be divided into three simple categories.

 The first is the river.
 The first is the river, which flows out from the south and slowly meanders from side to side as it extends to the north.
 It seems to go on for more than a few kilometers, although the forest and mountains looming in the middle prevent us from seeing the far end.

 I measured the river with my thumb, and found that it was six or seven meters wide at the narrowest point.
 The wide part seemed to be more than 20 meters wide.
 Crossing to the other side of the river would be a bit difficult.

 The flat land along the riverbank was quite wide, with tall grasses growing here and there.
 There was also brown soil here and there, which looked like muddy soil.
 It seems to be suitable for cultivation.

 The second is a forest.
 The meadow by the river is about a kilometer or two long.
 Along the way, there is a gradual increase in the number of trees and shrubs, and when the green suddenly becomes darker, a line of trees appears.
 However, the trees themselves do not seem to be very tall.
 Well, it's a good thing that there are a lot of trees, because they are a great resource.

 The third is the mountain.
 The third is a mountain. It is covered with greenery up to the top, so it does not seem to be high enough to reach the forest limit.
 The jagged ridges run close to the ceiling of the east and west walls, and there seems to be no other side of the mountain.

 The forest at the foot of the mountain is about several kilometers long, and the distance to the summit is probably about the same.
 The width of the mountain alone is almost 20 kilometers.

"Are you sure this place is underground, ......?

 Paula nodded quietly in reply to Noemi's question, which had become a familiar one every time.

Yes, it's an amazing view. This vast land will be all yours, my dear.
"No, it's not my property.

 No, I don't own it." I hurriedly interrupted him and he gave me his usual meaningful smile.
 Well, since the ownership of such things can be complicated, it would be smoother if I claimed it as mine, the discoverer.

"Another one!
"Meow, meow, meow!

 In spite of the beautiful scenery, the two of them and one of them seemed to remain unchanged.

 After finishing our meal, we decided to go to the river for a start.
 We checked the ceiling a few times, but could not find any flying beings in the air.
 So there was no need to worry about being suddenly attacked from above or being forced to go around the retreat.

 There was one thing that bothered me about the view of the ceiling, though.

"How can I help you, sir?
"Well, I don't think I can stay too long today. All right, let's get a move on. Take the lead, Tinya.
Leave it to me!

 Leaving the slow stone-faced frog to guard us, we headed west along the wall.
 After only fifty steps, we easily reached the source of the river.
 A huge amount of water was pouring out from under the wall.

It's pretty powerful," he said.
It's going to be hard to swim to the other side.
I can't swim! No way!
I'm not much of a swimmer myself. ......

 The riverbank here is dry, with only a few blades of grass, but nothing obvious.

Any sign of demons?
I don't think so, sir.
Hmm, I'm not sure either.

 I think there's something lurking in the water, but it doesn't seem to be around here.
 We decided to walk along the current for a while.
 As we walked along the river, Paula came up next to me and asked me curiously.

You said earlier that you couldn't stay long, may I ask why?
"Well, yes. You know Shirashoishi, right?
Yes, I do.
That stone has the effect of collecting light magical elements, but there are other stones that collect other magical elements as well.

 There are red hot stones that emit heat, black dark stones that have the opposite effect of white light stones, and so on.
 The most famous of these is the blue wet stone, which makes water drip.

 Many of the fountains in the underground labyrinths are supplied with large amounts of water by these stones.
 These stones are as useful as Shirashoishi, but they are usually buried under deep water or in walls, and are very difficult to mine.
 In this dungeon as well, it seems that all the water sources so far are in the walls, and I haven't been able to get any of them yet.

"I didn't know that. I apologize for my lack of knowledge.
I'm sorry I'm not well versed in alchemy. I'm sorry too. So, back to the topic at hand, I told you before that sunstone is the superior of white light stone.
"Yes, that dazzling brilliance. Oh, that's ...... by any chance?

You really are too perceptive for your own good.

 Paula glanced up at the sky, but seemed to notice something other than the rocks casting a white light.
 Here and there on the endless plane above her.
 Bare from the ceiling was a bluish mass of rock.

 At that point, something suddenly hit me on the cheek.
 Speak of the devil, I suppose.

 Starting with that drop, drops of water began to fall one after another.
 Tinya and Noemi shouted in panic at the drops that suddenly appeared above their heads.

It's raining! It's starting to rain!
What, are we really underground here?

 It seems that the fifteenth floor was also the place of origin of the rain-generating rock.