Zhang Gong walked in front and looked at the mountains on three sides carefully, and after thinking that there was no problem, he took out the shovel words from his backpack, knocked on the mountains a few times, and then said to Professor Chen: "Old Chen, these mountains on three sides are solid goods, and we have entered a dead end." ”

Professor Chen thought for a while and said, "Suddenly it feels weird, as if it is not as simple as entering a dead end. ”

"How do you feel this way?"

"Don't you think the air is getting thinner?"

"That's an illusion of nervousness, right?"

"When have I ever been nervous? Nervous enough to breathe?"

"So you mean we're locked up in a closed space?"

"Possibly!"

"What about the grave robbers?"

"They may have entered some hidden space, too."

"That means there are a lot of hidden intersections in this passage, now let's go back, where we go, everyone pay attention."

"But this is only a few minutes of walking, according to the speed of 50 meters a minute, now it is about 500 meters away, if there is any change within 500 meters, you should be aware of it."

"We're always going up, and it's not easy to block our way if we quietly lower the wall from behind or switch lanes."

When Professor Chen was looking down and thinking about where the problem would be, he suddenly discovered the secret on the ground, so he said: "Lao Zhang, I don't think we are always upward!" ”

"How is that possible? When I came in just now, there were steps, and although the difference was not large, it was obvious that it was upward. ”

"That's misleading, there's a strange slope here!"

"You mean visually misleading?"

"Yes, just like the strange slopes in Shenyang and other places, it looks upward, but in fact, it's not, you look at your feet, the saliva you spat just now, it's flowing straight ahead."

"Ahh If that's the case, then the length of 500 meters is enough to do tricks. ”

"The point is, what kind of mechanism is this?"

"If it's really misleading us with steps in front, and now there is a strange slope here, then there must be an article here!"

"What do you think this will be?"

"Wait a minute, I'll see how big this angle is, if there is a significant slope in the length of 500 meters, then there are more possibilities, the biggest possibility is the hidden passage mechanism, which hides multiple passages through vertical height difference."

Through several measurements, Zhang Gong said: "It is indeed inclined downward, but the angle is not big, 2 ° to 3 ° like that, if you use trigonometric calculations, tan multiplied by 500 meters, the vertical height difference is about 17-26 meters, if some places in front are indeed flat or high, then the drop may be much smaller, no matter what, it seems that we have to face the road behind us." ”

"Let's knock forward on the mountains on both sides, if there is a dark passage, then it can be judged from the feedback of the sound."

"Okay, let's do this by the two of us, you on the left, me on the right, one by one."

After saying that, they turned around and knocked all the way forward on the mountain, until another mountain appeared in front of them, and they didn't find anything abnormal every time they tapped, and the feedback sound after each knock told them that the back was solid.

Zhang Gongqiang, who was a little hypoxic, said with a smile: "It's strange, this kind of space design is really interesting, we seem to have been thrown into a big pit, but how did we get here?" Did it appear in this space out of thin air? ”

Professor Chen breathed a sigh of relief and said, "No, Lao Zhang, think about it, since there is no problem before and after, then the problem may be the same as what you said, we came down from above." ”

"We really threw it down!"

"Since the road has a slope downward, which means that we started from the top down, now let's measure the foot and see if the slope is still like that? If not, it means that the real passage is above our heads and under our feet, not by ourselves. ”

"Well, it's an idea, it's easy to do under your feet, the key is how we find the passage above our heads, that is, how to crack it?"

"The height difference here is only 2.5 meters, if it is really the same as someone removing the ladder, then there will definitely be a gap, let's not knock, look at the gaps on the top of the head and the mountains under the feet, if there is, I think it is our direction."

"You mean we got on the seesaw?"

"Being able to switch channels so quietly shouldn't be controlled by a conventional gravity mechanism, it may be in a way we don't know."

"And how do you test your judgment?"

"If it's the other way around, then my analysis is valid, and if it's not, then find a new idea."

"Hmm."

According to Zhang Gong's measurements, there is no slope here, and it is flat here, and obviously, Professor Chen's judgment was rejected.

Situ Fang saw that Professor Chen and the others had no ideas, so he walked up to him and said hesitantly: "Professor, I don't know if my idea is right, I think the way we leave here should still be solved by looking at the gaps, although I haven't been into the ancient tombs, and I don't know how the ancients designed the mechanism, but I think you have complicated simple things, you said earlier, look at the gaps, I think this is a way of thinking and direction, quietly realizing the mechanism switching, I think this is the same as the suspension bridge, it may be divided into three levels." And when we came down, the bridge was lowered, and when we came over, the bridge was closed, so we kept hitting it back and forth. ”

When Professor Chen heard Situ Fang's words, he said excitedly, "Situ, you continue." ”

"We can come here unconsciously, that means that the project is very large, first of all, the length must be very long, otherwise there will be obvious uphill and downhill feelings, since the length is long enough, then it is impossible to have no gaps, as long as the end of the gap is found, I think that is the end of the suspension bridge."

"Good! I think this is the most likely! Lao Zhang, what do you think? ”

Lao Zhang thought for a while and nodded and said, "I agree with this idea, but the problem is that even if we find the so-called suspension bridge end, then how do we put it down?" ”

"If we come down and inadvertently trigger the mechanism, then there will definitely be a corresponding mechanism opening method below, unless it is artificial, someone deliberately locked us in, in that case, we may really not be able to get out."