Situ Fang was also unsure which way to go, and after Professor Chen and Zhang Gong discussed, they took the lead to the left side according to the instructions. The road is very easy to walk, more than three meters high, more than two meters wide, the slope is not large, and it is also very dry, so they can walk very easily. After walking like this for a few minutes, after arriving at a platform about 5 meters long and wide, the passage changed direction and became downhill, and with it, the difference in the steps also increased a lot, and everyone could only slow down and walk down slowly. The further down he went, the more uneasy Professor Chen felt, for him, the easier and more comfortable he felt inside the tomb, the more it meant a trap, especially after the obvious contrast.

After walking like this for a few more minutes, Professor Chen seemed to smell something, he stopped and shouted loudly: "Situ, something is wrong in front of this, hurry back!" ”

Situ Fang was a little puzzled, turned around and asked, "What's wrong?" ”

"Did you notice the smell here? It's a little weird, but now I smell a little sour, which is very similar to the smell of white phosphorus when it spontaneously combusts! ”

Zhang Gong also sniffed hard, and his face turned pale in an instant, and he shouted: "It's not like white phosphorus spontaneously combusting, it should be where there is white phosphorus burning in front, and it is mixed with the smell of tung oil and pine branches, quickly turn around and run!" ”

No one spoke again, and the group quickly turned around as fast as they could and ran back. But now it was uphill, and the difference in the steps was very high, and they didn't run away very quickly. Six minutes later, seeing that there was the big platform in front of them, all of a sudden, a stream of heat came up from behind them. Professor Chen suddenly remembered the scene in the mural and shouted urgically: "Speed up, don't look back!" The smoke does not have the wind to roll, it moves upward, and it will be good if you cross the platform! ”

The group climbed and ran, and finally got on the platform. Situ Fang looked back again, but there was no shadow of fire except for the thick smoke, so he said to Professor Chen: "Professor, don't run, the fire hasn't come up." ”

Professor Chen gasped and said: "If the fire doesn't come up, we will have to cross this platform, this fire will not only burn the oxygen in the air, but also produce toxic gases and harmful suspended solids, so let's hurry up and take a few more steps." ”

As he spoke, the temperature became higher and higher, and the smoke quickly crossed the platform and continued to move forward, soon falling to the top of everyone's heads.

Seeing that the situation was not good, Zhang Gong shouted: "Everyone hurry up and run to the fork in the road!" Then see where the air is circulating, and we will be safe in another passage! ”

Soon, the group ran to the fork in the road. After all, it was downhill, and there was no obvious air flow, and the smoke did not follow quickly, so the group rested here first.

Everyone stayed like this for more than twenty minutes, except for a small amount of smell, the smoke just now did not appear again.

Zhang Gong looked at the passage, and after making sure that there was no smoke, he said to Professor Chen: "Old Chen, this road must not be walked, no, we should take the right side, right?" ”

Professor Chen took a few more steps into the passage on the left, and after feeling the temperature and air quality, he immediately retreated, turned off the flashlight and said, "No, we still have to go on the left!" ”

"Why do you want to go? Those two little ghosts know that they didn't kill us, so they must be hiding somewhere and holding back! ”

"I didn't think so, I now think they saved us."

Zhang Gong seemed to be enlightened, glared and said, "You mean that they went to light the fire in advance, so that we avoided a secret calculation?" ”

"Yes, it should be certain by now."

"Those two poor imps, who died for us like that?"

"Not really, I think they're very familiar with it, and they must be hiding somewhere."

"Then they led us over, and shed this thunder for us, what will be in this?"

"I don't know yet, but I know for sure that there must be a major discovery here!"

"Then let's go in now, and let this discovery come out to the world as soon as possible!"

"No, it's just burned inside, the toxic gas hasn't dissipated yet, and the temperature won't drop down soon, so let's wait."

"How long will it take, alas?"

"I just looked, there's a faint air moving in there, let's wait another hour, just sit down and fix it."

Taking advantage of the break, Situ Fang asked curiously, "Professor, are there many such organs in the ancient tombs?" ”

"Not much, except for the special treatment, many of the mechanisms in the ancient tombs have failed."

"I've seen a few movies about tomb robbing, and in a few films, tomb robbers are burned to death by fire oil."

"There is basically no saying that there is fire oil in the ancient tombs, and at that time the lamps only used animal and vegetable grease, except for the presence of biogas in some ancient tombs, there is no possibility of artificial liquid fuel, which is all the imagination of ignorant screenwriters."

"And how did this fire start?"

"It should be the use of phosphorus for spontaneous combustion, and then ignition of flammable materials such as rosin powder, and then ignition of dead grass and dried pine branches."

"In that case, it will burn slowly enough to pose a danger."

"This is not an arithmetic problem where one plus one equals two, when phosphorus and rosin powder are burned, high temperatures will be produced instantaneously, and highly toxic gases will be produced, in such an environment, people will not only inhale too much carbon dioxide, but also faint because of breathing too much toxic gas, since they faint, then the purpose of this mechanism has been achieved."

"It seems that the ancients were also insidious enough."

"This can't be understood in this way, they have exhausted their organs, just to protect their last territory, a little helpless, think of them as too protective and selfish, hehe, so we will be more comfortable."

"I'm glad we were born in an era of peace, and now I really feel sorry for the ancients."

"Every progress of ancient civilizations has a huge cost, and at the end of each competition, although it will destroy some civilizations, it is often the beginning of new progress."

An hour passed quickly, and Professor Chen walked back to the front of the group and walked quickly with everyone. When I arrived at the platform, except for a small amount of smoke, I could no longer feel the residual temperature of the fire just now. For the sake of safety, Professor Chen asked everyone to put on their masks and move on. As the traces of smoke on both sides became more and more obvious, the group came to a cloud of ashes.

Professor Chen carefully identified the ashes on the ground, and then said to Zhang Gong: "This should be the ashes burned by the pine branches, and the source of the fire should be this, so there will definitely be something confusing here." ”

Zhang Gong nodded and said affirmatively: "If this is the source of the fire, then there must be something on this side that confuses us, confuses us to touch or step on, so that certain mechanisms can be triggered, which will cause spontaneous combustion, and then cause fire." ”

Professor Chen looked at the top of his head, then at the cave wall, and finally stopped the flashlight at a peeling point, and after watching it for a while, he said to Zhang Gong with a wry smile: "There should have been a group of murals here, but it has been burned." ”

Zhang Gong leaned forward to take a look, sniffed it again, and comforted: "Since it is confusing, it doesn't matter if there is it or not, let's move on." ”

After speaking, Zhang Gong moved the light pillar of the flashlight to the front of the passage, and at this time, they saw the figure of the boy and the girl again.

Zhang Gong smiled bitterly, turned to Professor Chen and said, "What are they trying to make trouble this time?" ”