() After all the rubble on the mountain wall had fallen and the ground was no longer shaking, the three of them slowly stood up.

"Let's stop igniting the fire and just move forward in the dark." Ning Zhou was a little afraid because he remembered patting his chest.

It's just that because the flint and steel sparked, there was this kind of slight vibration explosion, so if this fire fold was really ignited, wouldn't the three of them be blown up and killed, and there would be no bones left here?

Bai Rong's face was a little dignified, but he still didn't figure out why such a slight magnesium element appeared in this place? Moreover, it seems that the content of magnesium is quite large.

However, she didn't think about it, just nodded and agreed with Ning Zhou's words: "Then let's be careful, go forward and try to touch the mountain wall, don't walk in the middle of the road, in case it is difficult to react quickly when encountering any danger." ”

Li Qi didn't have any opinions, and seeing that she didn't plan to throw away the instrument, she could only follow helplessly.

The more the three of them walked forward, the more frightened they became, they didn't expect that such a cave they had found at random would be so deep, as if it was a tunnel that had been carved out by someone.

When they reached this position, they could barely reach out to the extent that they could not see their fingers, and the slight light at the entrance of the cave seemed so far away at the moment, and the silence in the cave made them feel isolated from the world, as if they were in another world.

If it weren't for the presence of people around them, I'm afraid they themselves would have begun to doubt the authenticity of their own lives.

People are the most vigilant in the dark, even if their intuition tells them that there is no danger ahead, they still cautiously touch the wall and walk forward, for fear of encountering any danger.

It was they who were careful so, and there was still an accident.

"Ahh A miserable scream sounded, and the piercing Bai Rong's eardrum hurt, her heart jumped fiercely, and she hurriedly shouted: "What happened!" ”

After not waiting for the response she expected for a long time, the uneasiness in Bai Rong's heart increased again. When she was about to retreat, she heard Ning Zhou's weak response: "I almost fell." Three black lines appeared from the corners of Bai Rong's forehead, and he was speechless.

"It's okay, so what was your name just now?" Li Qi was not so good-tempered, Ning Zhou's scream just now made her heart tremble, and she almost thought that something had happened to him.

Hearing his voice at this moment, I felt like I was being beaten again

played a general, and couldn't help but scold angrily.

Ning Zhou trembled and said: "I stepped on the air just now, but fortunately, I sat on the ground with my back butt, so I didn't fall to my death." ”

"Empty?" Bai Rong grasped the point and asked quickly.

When they walked deeper into the cave, Ning Zhou took the lead, as the first in the team to walk in the front, after all, he was the only man among the three, and if there was any danger, he could quickly protect the people behind him.

Slowly squatting down, stretching out his hand to touch forward, Ning Zhou soon felt a big hole in front of him.

"You squat down and touch my position." Ning Zhou motioned for the two of them to grope for his position.

Soon both of them felt the hole in front of them, and they were speechless for a while.

"Is there a cliff in front of this?" Li Qi said softly.

Hearing this, Bai Rong frowned, she felt that this hole went straight down, and the height was probably not very low, if they jumped recklessly, I was afraid that they would end up with some kind of broken foot.

She listened on the ground, but she didn't hear anything from inside.

There's no exit from here? Bai Rong frowned slightly, a little hesitant. She looked back at the mouth of the cave where they had entered, and there was no lightning at the entrance of the cave, but she still had the instrument that could draw electricity, and I was afraid that she could not go back from the original way, and could only jump from this place.

Bai Rong couldn't make up his mind for a while, he couldn't retreat backwards, he jumped forward without any security, they didn't have any rope tools that could help them, if they jumped recklessly like this, no one could guarantee what danger would happen.

At such times, if there is a wounded player in the team, it will put a huge burden on them. They will not allow themselves to be hurt unless they have to.

The air was quiet and almost stagnant, and none of the three of them spoke, racking their brains to think of a way, but none of them could think of anything in their minds that would ensure that everyone was safe and sound.

"Ning Zhou, give me your watch." It took a long time for Bai Rong to speak.

Ning Zhou asked: "At this time, it is dark, and there is no light or fire, can you see the time for you?" He looked in Bai Rong's direction suspiciously, but he couldn't see Bai Rong's face, so he couldn't see her expression at the moment.

"It's okay if you don't give it to me, then stick your watch to your ear, and count the time." She said softly.

Then, she took out a fire fold from her bag and placed it on top of the hole: "Are you ready?" She looked at Ning Zhou.

But Ning Zhou still didn't understand: "What are you going to do?" ”

"She wants you to calculate the time it will make a sound after the fire fold falls to the ground." Li Qi really couldn't stand it, and he didn't have a good airway.

And Ning Zhou reacted at this time, and hurriedly said that he was ready, put the watch next to his ear, and began to prepare to time silently in his heart.

"Smack."

The sound of things falling to the ground came from the bottom of the cave to the top, and there was an echo in the cave.

"That's about that." After Ning Zhou reported the number, Bai Rong's brain was running rapidly.

Based on a conduction formula she had seen before, she could use the reverberation of sound to figure out how high an object would be when it hit the ground.

"One hundred meters." Bai Rong's face was a little pale, and she reported the number in a low voice, and the scene was silent for a while.

"This, so high." Ning Zhou's face was already white, he was already a little afraid of heights, and when he almost fell, he didn't expect it to be such a height, and now he already felt a little dizzy after hearing it, let alone jumping down.

Bai Rong's face is very ugly, at this height, if you jump, you will either die or be injured. The height of a one-story building is three meters, and one hundred meters equals about thirty floors.

As far as her cognition was concerned, she had never seen anyone jump from the thirtieth floor and still live unharmed.

"So, is it good for us to know this height?" Ning Zhou's voice revealed a faint despair, let alone a hundred meters, even if he was asked to jump down ten meters, I am afraid he would pass out directly.

Jumping down at this height, it is better to let him die directly at the entrance of the cave, and he can still die happily.

"Why are you all so pessimistic, why don't you ask me?" Li Qi's voice rang out at this moment. After hearing this height, there was no despair in her voice, on the contrary, it also revealed doubt.

She took out a large roll of rope from her waist and handed it to Ning Zhou: "Find a place to fix it, and then we will go down." ”