Yu Fan's words were like a needle, piercing everyone's skin, making everyone very vigilant and very afraid.

Chen Jieyang didn't know why Yu Fan said this, so he asked: "Old Yu?" You say this lake kills? ”

Yu Fan nodded and said, "That's right, if we really set foot on this boat, then the five of us are destined to die here." ”

The word "death" is very calm in Yu Fan's mouth, after experiencing Zi Yan's sacrifice, Yu Fan has grown a lot, and his heart is more resolute and strong.

Shen Wei was so frightened that he tightened his crotch and said in surprise: "What about me? Isn't it so scary? Will people die? Dude, don't bluff me. ”

Yu Fan said calmly: "I didn't bluff you, I will really die." ”

Xinling guessed: "Do you mean that there are really water monsters in this lake that will eat people?" How can I ......"

"No, there are no water monsters in this lake," Yu Fan interrupted Xin Ling's words, "What lives in this lake is the Grim Reaper!" ”

Everyone opened their mouths in surprise and moved further away from the lake.

Yu Fan pointed to the white smoke on the ground and said, "Here's the problem!" ”

Everyone lowered their heads, and when they saw the white smoke looming on the ground, some of the second monks were still confused.

Yu Fan said to Chen Jieyang: "Old Chen, borrow me your lighter." ”

Chen Jieyang let out an "oh", took out the lighter from the side of the backpack, and handed it to Yu Fan.

Yu Fan took the lighter and lit it in front of everyone, the flames flickering and jumping.

Yu Fan slowly moved the lighter downward, everyone stared at the flame intently, only to see that the flame seemed to start to get weaker and weaker, and when Yu Fan placed the lighter near the white smoke on the ground, the lighter went out.

Everyone is even more confused, what is the situation?

Chen Jieyang asked: "What is this white smoke?" This white smoke is poisonous? Why is the lighter fire extinguished? ”

Yu Fan didn't answer directly, but instead asked, "Have you felt some changes in your body?" Do you feel that your consciousness seems to be starting to blur? Do you feel like your memory is bad? Physically tired? ”

That's when everyone realized the problem.

Shen Wei said: "I just feel that the glasses are a little flowery. I can't see anything near anymore. ”

Xinling also said: "I also feel that my brain is cloudy, and I think it is the reason why I didn't sleep well." ”

Guo Na: "I feel out of breath and sweating. ”

Yu Fan nodded and said, "That's right!" This is the ghost of this white smoke! ”

Chen Jiaoyang hurriedly asked, "What is this white smoke?"

Yu Fan: "This white smoke is not a poisonous gas, it is just the carbon dioxide gas we usually exhale." ”

Xinling was very puzzled and asked again, "Huh? Why? ”

Yu Fan: "Just now I put the lighter close to the white smoke and extinguished it, because the carbon dioxide concentration was too high, and the oxygen concentration was too low to cause the flame to go out. And the condition of our body is also a typical precursor to carbon dioxide poisoning! ”

Yu Fan paused and said: "Carbon dioxide poisoning is caused by being in a low-concentration carbon dioxide environment for a long time or suddenly entering a high-concentration carbon dioxide environment, the former is mainly manifested as headache, dizziness, lack of concentration, memory loss, etc.; The latter is mainly manifested as cerebral hypoxia symptoms, which can cause reflex respiratory arrest and sudden death. Under normal circumstances, the amount of carbon dioxide in the exhaled air is about 4.2%, and the partial pressure of carbon dioxide in the blood is higher than that in the alveoli, so the carbon dioxide in the blood can diffuse in the alveoli. However, if the concentration of carbon dioxide in the environment increases, the concentration in the alveoli also increases, and the pH changes, which stimulates the respiratory center and eventually causes paralysis of the respiratory center and hypoxic asphyxia in the body. Low concentrations of carbon dioxide have an excitatory effect on the respiratory center, and at high concentrations, it has an anesthetic effect on the central nervous system, often accompanied by hypoxemia caused by a decrease in fluoride content in the air, and can also inhibit breathing, resulting in a series of central nervous system symptoms. ”

Guo Na asked, "Brother Yu, how did you find out that this is carbon dioxide?" ”

Yu Fan: "The density of carbon dioxide is relatively high, I saw that the white smoke was almost close to the ground and the surface of the lake, coupled with the bad condition of our body, and when we just went down the mountain, there was no trace of animal life in the vicinity, so I had this guess that the 'environment' here must not be conducive to survival, and finally my experiment with a lighter also confirmed this." ”

Shen Wei still had questions: "It's strange, where did so much carbon dioxide come from?" ”

Yu Fan: "According to my analysis, the geological structure here is special, and the bottom of the lake may be a hot spring, and there is a large amount of carbonate in the spring water. The water from this spring is constantly poured into the lake, causing carbon dioxide to accumulate. Then, due to some changes in the geological structure, the pressure balance at the bottom of the lake was broken, and a large amount of stored carbon dioxide gas was released, resulting in a high concentration of carbon dioxide around the lake. In fact, I have heard of this phenomenon before, in 1984, there was such an incident of carbon dioxide release in the lake in Cameroon, a West African country, when nearly 50 people died in that disaster, at first, people thought it was the punishment of the gods, and it took a long time for scientists to find the real culprit - carbon dioxide. ”

"If we had just gotten on the boat and the carbon dioxide concentration in the lake was higher, we would have been poisoned more before we knew it, and by the time we realized the seriousness of the problem, we might not have the strength to row back again," Guo added. ”

Yu Fan slowly closed his eyes and opened them again, and said, "Yes, at that time, we were already in the palm of the Grim Reaper's hand. ”

The more everyone listened, the more frightened they felt, and everyone slowly realized the seriousness of the matter, Yu Fan just relied on his keen insight and long-term accumulated professional knowledge to forcibly drag everyone back from the death line. If it weren't for Yu Fan's awareness, all of them would surely die!

Chen Jieyang continued to ask the question: "Then the question arises again, who is this ship parked here?" Could it be that his purpose is to lure us in the bait? Deliberately trying to kill us with high concentrations of carbon dioxide in the lake? The ship was a trap from start to finish? ”

Yu Fan shook his head and said, "I don't know, but I don't think the person who parked the boat here is not our friend, since he came to the boundary of Ziwu Village, there have always been people who want to attack us, and they are still dead!" And the means are getting more and more ferocious, we have to find the clue of the ghost god Gaicao as soon as possible, maybe the truth will be revealed! ”

Guo Na agreed with Yu Fan's point of view: "What I said is, let's continue to set off, the truth may be right in front of us!" ”

Yu Fan, Guo Na, and Chen Jiaoyang continued to move forward, but Shen Wei stood still.

Chen Jiaoyang shouted at Shen Wei: "Little brother, continue to lead the way, why are you stunned there?" ”

Shen Wei looked vigilant and said solemnly: "Who are you?" ”