Dense lines of rain poured down, slanted by the wind that came from nowhere.

Wen Ding stood in a huge hole, watching the heavy rain that had not stopped outside, followed by Kai.

Before leaving, Qi told Wending that it was summer, and there was a lot of rain, so it was impossible to go too far.

"There are four seasons here, too." Wen Ding thought to himself.

"This rain...... There is a problem. Wen Ding stretched out his hand to take a handful of rainwater, and the rain did not have the freshness of the soil that the rain should have, only a slightly pungent smell diffused.

This is the smell of gasoline.

Wen Ding sniffed it again, it was too similar, although it was very light, but Wen Ding was sure that it was the smell of gasoline.

"Do you have tinder?" Wen Ding poured out the water in his hand, took out a small clay pot from his bag and stretched it out.

The rain soon filled the clay pot, and Wen Ding placed it on the ground.

Kai nodded, and took out a small bamboo tube with a lid from the bag wrapped in animal skins.

Wen Ding took the bamboo tube, took off the lid and blew on it, and a flame appeared. This is how people save the fire here.

This thing is very similar to the fire fold invented during the Northern and Southern Dynasties in China in the book, the only difference is that the fire fold is an unburned roll of paper, while there is no paper here, wood chips are used.

Wen Ding handed the flame to the clay pot, but it did not burn as Wen Ding expected.

"It's gasoline, but it's too low to light it."

"What are you doing?" Qi couldn't understand the meaning of Wen Ding's action, and asked suspiciously.

"Nothing, I'm validating my idea."

"Succeeded? I don't see much change. ”

Wen Ding lit it for a while, but the rain in the clay pot did not react, so he closed the lid again and returned the fire to Qi.

"It didn't work out, but I don't think I smelled it wrong, it smelled of gasoline."

"What is gasoline?"

"We have a fuel there."

"We've lived here for generations, and we haven't heard of a precedent for lighting rain."

Wen Ding was thoughtful and asked, "When can we go?" ”

"Wait for the rain to stop and go."

"I remember that kid named Liyang said that bamboo umbrellas will be eroded by rain, what does it mean?"

"Bamboo umbrellas are used to protect from direct sunlight, and when rain falls on them, the bamboo umbrellas will slowly rot."

"Corroded?"

"I don't know what corrosion means."

"......." Wen Ding didn't want to explain the meaning of the word corrosion, and instead asked, "Is this true for all bamboo products?" What about people? Will it be hurt by the rain? ”

Qi nodded, and then shook his head: "Rain only has this effect on bamboo products, and it is harmless to people." ”

"What about the bamboo forest outside the patriarch's cave? It is impossible for the skylight there not to let in rainwater. ”

"The skylight is not directly facing the outside, in fact, most of the skylights you see are two floors, and they are curved structures." The hand gestured in the shape of a "C", "The upper layer is painted with a thing made by the first patriarch, which can reflect the sunlight, and the sunlight will gather together when it is reflected, just like you see the light in the well, which shines on the book, and is reflected to the second layer, and then shines on the place where the sunlight is needed, and there will be a hollowed-out passage at the corner between the first and second floors, which is connected to the earth walls connected to the upper layers, which are actually hollow, and are connected to the nearby filter pipes, The water in the filter pipes will come out of some wells and can be drunk directly. ”

"In other words, this is a creation more than 1,000 years ago, and it has not rusted? Rust is... Yellow, green, or something like that. ”

"We haven't dug it up either, but none of the iron vessels we have here have ever been discolored."

Wen Ding sighed, and looked thoughtfully at the rain scene outside the cave, as far as the eye could see, there were no living creatures, no trees, and a few bare rocks in the distance, mottled weeds like the ground, which were plants that Wen Ding had never seen before, like shrunken banana leaves, but there were many white filaments extending from both sides and connecting to the ground.

"If you're looking for a river, I've chosen this place, to the west of the tribe." Kai took out a hide from his bag, "This is the map to the west." ”

Wen Ding looked at the pattern on it and found that it was written with a pen, and Qi saw Wen Ding's doubts: "We just don't use paper anymore, and the pen naturally still exists." ”

There are many strokes on the map, and Kei gives Wending an indication of where it appears.

"This is drawn after the personal experience of generations of explorers, and we have repeatedly confirmed it many times, it can be trusted, this pattern is a river, the closest one to us is here, about more than 40 kilometers."

"Is this an equiscale diagram? It is... For example, it's 40 kilometers from here, and then it's 40 kilometers from here? Wen Ding gestured with his finger and panned to the next place.

"No, because the time we go out is limited, we all count our steps to judge the distance, there is no detailed measurement, but it is roughly the same."

"Each of the previous team members will bring animal skins and pens, record the route and terrain, and then you can summarize after camping, and then copy two more and put them in this box, which is made of wood, and will not be broken by the rain, stay in place and then go to the next location, if it exceeds a certain time, the soldier elder will send the next exploration team, and return directly to the cave after getting the wooden box in the camp, if you pass through the blue sun twice, the first team has not returned, it means that they have all died on the road, and the next team can be sent, The cycle goes on and on, and we already have a map of a 200-kilometer radius, and this is only a map of a partial area. ”

"Only two hundred kilometers? In our place, we can't even get out of the province. ”

Although Kai didn't understand the concept of "province", he didn't ask much: "It's already very good to be able to go out for two hundred kilometers, the time of the red sun is limited, the time we go out every time is limited, the farther we go, the easier it is to not come back, we will also leave the excess supplies in the camp to facilitate the next exploration, I don't think we will go out for a long time this time, after all, you are the first time to explore, try to follow me, although you are not afraid of the blue sun, but after all, there is no experience." ”

Wen Ding said he understood.

While we were talking, the rain had stopped.

Kai looked up at his head, it was something like a corona, on the earthen pillar next to each skylight.

"It's been exactly twenty minutes, and there is no situation described by Liyang, let's go."

Kai tightened his bag and flung it onto his back.

"There was no road here, and our exploration team members walked out step by step."

Wen Ding silently calculated in his heart: The speed at which humans walk is about eleven to fifteen minutes per kilometer. It takes about 10 hours to walk 40 kilometers.

The road here is very flat, occasionally there are a few undulating stones, it stands to reason that it will not fog when it rains just now, but there is always fog lingering in the distance, a little depressed and cramped, Wending feels that he is still in the cave, but the earth color has been changed to a hazy fog.

Wen Ding sighed, glad that he was not claustrophobic: "Why do you want to go out so much? Are there any benefits to going out? ”

"Because we've been working hard to get out there for generations."

"This is not a reason at all, at most it is a trust in the ancestors."

"Because... I can't describe it with my current vocabulary, I don't know how to say it, but that's probably what it means, and when I understand it, I'll describe the reasons to you accurately. Kei said very seriously, although sometimes a little dull.

"Okay." Wen Ding responded, and then kept silent.

It would take ten hours to walk, and both of them knew that they should conserve their strength.

I don't know how long it took, the fog had cleared, and Wen Ding had become accustomed to the faint smell of gasoline in the air: "How long have we been walking?"

Qi was carrying his bags and panting a little, but Wen Ding didn't carry anything because he wasn't afraid of the blue sun, and he didn't consume like Xiang Qi.

Pulling out a disc from his bag, Wen Ding saw Qi pull the button-style thing on it a few times, and then turned to the sun.

"Table?"

"It's not a watch you know, but listening to the patriarch's description, it's really very similar to it, in our language, it's called the chronometer, facing the sun, and this refers to time." Kei pointed to something that resembled a watch hand.

"In my hometown, there is also a way to judge the direction of the watch, which is very similar to the action you just made."

"In this way, our tribe should be able to communicate, at least there are similar things, the bamboo slips in the light well said that living things will change with the environment from generation to generation, and I am really afraid of meeting a tribe that is completely unable to communicate."

"That's—"Bang-boom-"

Before Wen Ding's words were finished, a strange sound was heard.

"It's thundering, it's going to rain, and the blue sun should be coming." Qi quickly opened the umbrella, and the moment Qi opened the umbrella, the raindrops hit the bamboo umbrella, and Wen Ding didn't react, so he got wet directly.

Qi saw Wen Ding reach out and want to hold the umbrella, but when he touched the bag, he withdrew his hand.

"Why don't you hold an umbrella?"

"It rains a lot here, doesn't it? Li said it. ”

"Yes, it will go down three or four times a day, twenty minutes at a time."

"It's okay, I don't have an umbrella, it might be useful to keep it."

Qi didn't ask much, Wen Ding kept staring at Qi's umbrella, which was a very heavy umbrella, there were two

Layers of bamboo are interlaced with each other to provide shade from the rain and sun.

The sky suddenly darkened, as if a dark cloud was obscuring the sun, but looking up there was nothing, Wen Ding squinted at the sun - he wanted to see how the sun changed color.

The sunlight is a little harsh, and even though it is fading, there is still unparalleled light and heat.

The surrounding environment also became darker, and thunder kept coming from all around, Wen Ding noticed that there was no dark cloud in the sky, but it was raining all the time, and the sun in the distance suddenly flickered, and in the next moment, a round of blue sun had appeared in the field of vision.

"Huh?"

Wen Ding was puzzled, he was sure that he didn't blink, just for a moment, faster than the two frames in the animation, the sun changed color.

Qi held the umbrella, still walking unhurriedly, and the bamboo umbrella was slowly rotting and blackening.

"An umbrella can last for about twenty minutes, and it can survive this blue sun... Well, the time has come. ”

As soon as the voice of Qi fell, the last drop of rain hit the umbrella, Qi flung back, the umbrella bone collapsed, and became an inconspicuous pile of debris on the ground, the sun had turned back to red when Wen Ding caught up with Qi, Wen Ding noticed that there was no process of darkening from the blue sun to the red sun.

"This can be used as a signal to the team that we are on this path."

"So confident?"

"I just trust my companions."

"I mean, you're so confident that you just threw your umbrella, what if it's still a blue sun?"

"I knew it was going to change back."

"How do you know?"

"I don't know, maybe it's just that there are too many tasks, and I can already feel it."

Wen Ding shook his head: "Trust your instincts too much, and you will make mistakes." ”

"Intuition... It turns out that this feeling is these two words in your language. ”。

Qi didn't say anything more, he still walked forward calmly, and the conversation changed: "There are still a few hundred meters to the camp." ”

Wen Ding looked in the direction that Qi pointed, and a wooden hut stood quietly, waiting for the arrival of the two.