Night, after immersing everything, the faint moonlight shines through the treetops, shining on a strange figure, and in the sound of insects, the shadow quickly typed something on the fluorescent mobile phone, and two minutes later, the shadow quietly burrowed into the tunnel.

Early the next morning, according to the division of labor, each of them led the team to start the search for the entrance to the entire tomb. According to the work deployment, Zhang Gong and Ma Kai also used a three-dimensional imager to conduct a comprehensive scan of the entire tomb. After scanning for most of the day, it was found that under the center of the temple, in addition to the pit where the chess endgame mechanism was originally placed, further down, there was also a large passage hidden, which went down in a spiral shape and had a large depth, and the specific depth has not yet been detected.

Professor Chen turned around a few times in the tunnel where the mechanism was placed, and saw that the entire tunnel was directly excavated from the mountain and was made in one piece. Except for the iron chain passage used to place the secret room where the bamboo slips were placed, there were four large stone slabs at the feet, and nothing else was found.

Zhang Gong looked at the stone slabs below and said: "Lao Chen, the structure of this mountain is stable, the stone slab itself is to cover the ears and steal the bell, there is no silver three hundred taels here, and the preliminary judgment is that the thickness of this stone slab is more than one meter, if it doesn't work, it will be blown up, and now I really can't find where the organ is, or the mechanism here is the same as other ancient tombs, and it has already been rotten." ”

"I don't believe it will happen if the mechanism is rotten and fails, at the moment all the mechanisms here can be used normally, you know this, if you can't find the trigger point of the mechanism, it means that we have left out some details, look for it again, don't use explosives at every turn, then I will be no different from a tomb robber."

"And where is the trigger point for this mechanism? It is known that there is a passage underneath this pit, but the method of activating this mechanism is currently unknown. ”

"Since it's unknown, let's take a closer look at this wall, there should be details, the triggers of the mechanism are all laid nearby, not too far away."

"The key is that this place is completely excavated from the mountain, and no information can be found!"

Seeing that Professor Chen did not reply to him, Zhang Gong used a 3D imager to scan the surrounding area of the tunnel in detail again, and carefully recorded every detail on paper. As he zoomed in, he sketched out the roundabout. From the sketch, it can be seen that starting from the edge of the ring of the Hanoi circle, there is a space about three meters wide below, this ring space is wide at the bottom and narrow at the top, the edges of the four large stone slabs under the tunnel are just on the edge of the ring of the ring, and on the four sides of the underground passage, there is a pit chamber of about three meters. Through Zhang Gong's sketches, it can be determined that the article of the organ is on these four stone slabs, but the focus is on how to open these four stone slabs, which is still not found.

Zhang Gong communicated the detection results with Professor Chen and said: "Old Chen, this may be a flap mechanism, it should be through where to turn up these four stone slabs, so that the passage will be opened, but now I can't find any information about the opening mechanism." ”

"Yes, I also think this is a flap mechanism, the focus of the flap mechanism is balance, then the way to destroy the mechanism is to unbalance, the way is relatively simple, nothing more than the formation of an imbalance through external force or gravity, the middle part is erected on the hidden channel, so it is impossible to apply force or open to the middle, that is to say, this mechanism can only make a fuss at the edge, and the four tunnels you newly detected should also provide space for the corresponding stone slabs to be erected."

"If it's opened from the edge, then the edge part is in the ring, and the dirt inside is three meters thick, how did it trigger? Or is it hidden in the dirt? Shall we dig up this earth? ”

"Let's take a look at the river first, I think we're missing something."

Accompanied by Chen Zhijun, Zhang Gong and Professor Chen came to the soft river.

After Chen Zhijun grabbed a handful of soil from the riverbed, he found that the riverbed was not filled with mud, but yellow sand, or coarse sand that had been cleaned. Chen Zhijun asked suspiciously: "Dad, what are you doing with yellow sand here?" Simply used to pave the riverbed? ”

Professor Chen also grabbed a handful of yellow sand, pinched it with his fingers, put it under his nose and sniffed it, saying: "The yellow sand here is nothing special except for being very thick, dig it, don't study it." ”

After calling the old horse for their help, they quickly dug a hole in the circular river. When digging about one meter, the width of the river suddenly shrank, and the originally excavated river channel was indented by about 50 cm from each side, and the original golden yellow sand was gone, and the bottom was replaced by yellow-green fine powder. After Chen Zhijun stood on the side and found out about this situation, he immediately stopped: "Wait, don't dig yet, the soil below is wrong!" ”

At Chen Zhijun's call, Professor Chen and Zhang Gong immediately walked over from the stone bridge.

Zhang Gong grabbed a handful of yellow-green soil, pinched it, smelled it, and then licked it with his tongue and said: "Lao Chen, this is not ordinary soil, a pinch of your hand is like talcum powder, this soil is artificial?" ”

Chen Zhijun also grabbed the picture and pinched it and said to Zhang Gong: "Uncle, this should be bentonite, a natural thing, which has been broken and screened." ”

After Zhang Gong heard Chen Zhijun finish speaking, he looked at the soil in his hand again, and asked suspiciously: "Bentonite?" What is it mainly used for? ”

"Bentonite is to put it bluntly, it is a non-metallic mineral based on montmorillonite, used in many places in industry and agriculture, bentonite can absorb 8 to 15 times the water of itself, and the expansion rate can be up to 30 times its own volume, but it seems that the Han Dynasty did not find this thing, right? I don't know the specifics. ”

Professor Chen heard Chen Zhijun say that bentonite can expand when exposed to water, and it can expand so much, and immediately understood the way to open the mechanism, he and Zhang nodded thoughtfully, and both of them tacitly knew what to do next.

"Old Chen, it seems that we have indeed ignored a lot of details, and in the morning we found that there is a small hole in the north that leads from the direction of the main tomb to this circular river, and then follow that upward, you should be able to find the key to open the door of this passage."

"Yes, I really didn't expect that the ancients would use bentonite as a trigger, and the wisdom of the ancients is often not something that we modern people can understand. Follow the hole you said and look up, the place where the water source is connected should be in the Backrooms, as long as you follow the hole, you will definitely find the water source. ”

After instructing the old horse to backfill it, the three of them followed the message from the hole through the main burial chamber to the back rooms. As with the analysis, the hole was connected to the mountain through the middle of the northern part of the Backrooms.