"You see the end of the tightrope? So, is there something tied down there? Ziyang asked with wide eyes. In his mind, it must be a very heavy load that can drag this excavator into the water.

Su Rui shook his head: "This is exactly the strange place, the end of the steel cable has been broken, looking at the appearance of the fracture, it seems to be ...... It was bitten off by something. ”

"Are you sure?" Jin Guoqiang frowned and said, he had read Su Rui's information and knew that she had a degree in physics, and there should be no problem with her common sense and judgment, but the thick steel bar of her fingers was bitten off - this is also too unbelievable.

Su Rui hesitated, "I'm not completely sure, but I've carefully observed the incision, and it doesn't look like it's stretched or truncated." ”

Jin Guoqiang groaned, "Something that can break such a thick steel bar must be a behemoth, does such an underwater creature exist in nature?" ”

Su Rui muttered, "As far as I know, no—my intercom malfunctioned at that time, and my helium was immediately used up, and I was a little nitrogen-drunk, which may have affected my judgment." ”

"For the sake of safety, I advise you to give up the exploration, Professor Zhang and they hurriedly withdrew, which also means that they may have encountered danger underwater." Jin Guoqiang said seriously.

"However, I can already see the bottom of the pool, just a few meters below the cable. If you go down again, there will definitely be more to discover. Su Rui said with some regret.

"But we don't have enough air bottles left now, so we can't dive again." Although Ziyang said this, he had a sense of relief in his heart - it was not that he was afraid of retreating, I had tried my best, but it backfired.

It is also a relief to be able to find a reasonable excuse for your failure.

But Su Rui didn't seem to understand Ziyang's "hard work", but said seriously: "It's not enough for two people to go back and forth, but one person is still fine." ”

"Then what's the matter, didn't you say, you can't dive alone." Zi Yang tried hard to dissuade Su Rui.

"Actually, we also have a set of diving equipment." Su Rui said, "When I was preparing the equipment this time, I didn't expect to dive so deep, so I didn't have enough air cylinders and helium cylinders to prepare. But a friend from Columbia University had sent me a sample of a scuba set. I also brought it with me, this set of equipment is very advanced, even beginners like Ziyang can use it to dive to great depths, and the battery life is very long, so you don't have to worry about running out of air. ”

"This ......" Zi Yang heard Su Rui say this, and could no longer find an excuse to shirk, so he could only look at Jin Guoqiang for help.

Jin Guoqiang looked up at the sky and muttered, "It seems to be raining heavily." ”

Sure enough, the sky was still clear in the morning, and suddenly dark clouds were thick, and it looked like a heavy rain was coming.

Lao Wang's voice suddenly came from the walkie-talkie, "Hey, hey, hey, Lao Li!" It looks like it's going to rain hard, Brother Chic said that it is not safe to continue climbing, and suggested that we return, what is your opinion? ”

Jin Guoqiang took out the walkie-talkie from his backpack and handed it to Ziyang.

"Okay, that's what I thought, how long will it take for you to get back to camp?" Ziyang said into the walkie-talkie.

"It's going to take at least two or three hours, oh my god, it's too tiring to climb a mountain!" Lao Wang burst into foul language in the walkie-talkie.

"We're pretty much the same, then you come back quickly, gather at the camp, and pay attention to safety on the road."

Zi Yang finished lying without blushing and panting, turned off the walkie-talk, looked at Su Rui and Jin Guoqiang and said, "Why don't you do this today?" Let's go back to camp and talk about it? ”

Jin Guoqiang and Su Rui nodded together, and when everyone packed up their equipment and returned to the camp, there were already dark clouds rolling in the sky, thunder and lightning. Zi Yang looked at the direction covered by the thunderstorm, which was the "mountaineering route" he and Su Rui had chosen—if they did go mountaineering.

"Hey, Lao Li, are you in the tribulation? Beware of being struck by lightning! Lao Wang didn't forget to joke with Ziyang at this time.

"You are less sassy, and now you dare to speak with a walkie-talkie, be careful of lightning slashing you!" Zi Yang turned off the walk-in, looked at Su Rui and asked, "Will you be hacked if you call on a thunderstorm?" ”

Su Rui pursed his lips and smiled: "No, the wireless frequency of walkie-talkies is lower than that of visible light, and basically it will not cause air ionization." ”

"Strange, then why do I always hear that you don't use your mobile phone to make calls on rainy days, is this a rumor?" Zi Yang said with a puzzled expression.

Su Rui smiled: "If the phone call can attract thunder and lightning, the danger of turning on the lights is even greater. The only thing you need to pay attention to when calling on a thunderstorm day is to speak loudly, or you can't hear clearly. ”

Zi Yang smiled and scratched his head awkwardly, Jin Guoqiang was not moved by their jokes at all, and looked up at the sky with a gloomy face, "I'll go back first, I don't know how Wang Juan's body is." If you have something, you know where to look for me. ”

"Wait a minute." Su Rui took out some chocolates and compressed food from their luggage, put them in a plastic bag and handed them to Jin Guoqiang.

"Here's for you."

"Thank you!" Jin Guoqiang took Su Rui's things and said gratefully. After thinking about it, he stopped talking, turned around and walked out of the yard.

Seeing Jin Guoqiang's figure disappear in the distance, Zi Yang and Su Rui glanced at each other, reloaded all the diving equipment into the box and locked it to avoid being discovered by Xiaoli and Brother Xiaoxiao.

"Xiao Hei, can you go out and see if you can catch some game and come back?" Ziyang instructed the little underworld.

Xiao Hei turned around and walked out.

"Come back when it's raining! Don't wander outside! Zi Yang shouted behind Xiao Hei, seeing Xiao Hei's back disappear, Zi Yang turned his head to look at Su Rui, and the two finally had a rare time alone.

Su Rui didn't notice Ziyang's "eager" eyes, pointed to a suitcase and said: "This is the underwater drone we bought before, and it will be used for the next deep dive, but there is still a person on the ground to operate it remotely." ”

"Oh." Zi Yang said with some disappointment, it seems that Su Rui still has to go for a deep dive.

"Also, while Lao Wang and the others haven't come back, I'll teach you how to use this set of circulating underwater breathing apparatus." Su Rui dragged a large box out of his luggage. I opened the combination lock and rummaged through the box, revealing a black respirator.

Unlike the underwater scuba that Zi Yang had seen before, this one was more compact, with no bulky oxygen cylinders hanging on the outside, and three bottles the size of a small fire extinguisher on the back, encased in a black plastic shell, through which several thick tubes were attached to the mask.

"Is there a manual for this thing?" Zi Yang saw that there was also a head-up display on this set of rebreathers, and couldn't help but be curious.

"There is no manual, this is a test product, and there is no industrial mass production." Su Rui shook his head.

"Tsk, that's not cheap, is it?"

"Well, tens of thousands of dollars. A friend from Columbia University sent it to me in the hope that I could help them program. ”

"Programming? Does this thing still need to be controlled by a computer? ”

"Yes, the principle of the rebreather is to operate by repeatedly breathing its own air, and the exhaled carbon dioxide passes through a sodium hydroxide filter, and the carbon dioxide reacts with sodium hydroxide and calcium hydroxide to form calcium carbonate to produce new oxygen, so the exhaust gas can be recycled.

Friends at Columbia University use lithium hydroxide to filter carbon dioxide — a bit dangerous, but much more effective than calcium. So the oxygen cylinder that needs to be carried does not need to be so bulky. “

Su Rui flipped the hood, pointed to a bottle and said, "This is a spare oxygen tank, which can inject fresh oxygen into the breathing circuit. The sensor monitors the gas composition and concentration in the respirator and then controls the oxygen concentration and nitrogen content in the breathing circuit via a microprocessor. Adjustments are made differently depending on the depth of the dive – these need to be controlled with precise programmes.

Because nitrogen is kept to a minimum, decompression is much less complicated, allowing for deeper dives and longer time spent underwater. Theoretically, a skilled person can stay underwater for more than 20 hours with this rebreather. ”

After listening to Su Rui's introduction, Zi Yang was speechless: "Sure enough, science and technology are the primary productive forces, and this kind of high-tech sounds very scary." ”

Su Rui smiled and said: "Actually, this is just a very conventional technology, the nano clothes we used before are the real super era products, but unfortunately ......" Su Rui suddenly frowned when he said this, as if he had thought of something.

Zi Yang was also stunned when she heard her say that the nano clothes they had worn in the underground abyss didn't know who took them later.

Zi Yang suddenly thought of Saiyan, speaking of which, this guy hasn't appeared for a long time, is it really dormant?

The two of them each remembered what was on their minds, and for a moment no one spoke, and the air suddenly fell silent.

At this moment, the walkie-talkie in Ziyang's bag rang: "Lao Li, something happened!" Lao Wang shouted in fright.

"What's wrong?" Zi Yang chuckled in his heart, seeing that the wind outside was blowing the leaves loudly, the clouds were thick above Qinhan Village, and it was vaguely seen that the mountain peaks in the distance were already shrouded in the rain curtain - this rainstorm came so quickly, Lao Wang, they shouldn't have encountered any accidents, right?

After a while, the walkie-talkie sounded again, and Lao Wang shouted breathlessly: "Xiaoli slipped when she went down the mountain, rolled more than a dozen eggs, and her feet were broken, and she couldn't walk." ”

"Give me the coordinates and we'll pick you up!"

When Zi Yang and Su Rui ran to the river across the valley, they saw three figures moving slowly towards them from a distance, and a rain cloud was chasing them.

Ziyang looked down at his feet, the river was about to rise to the bridge deck, standing on the bridge and looking into the distance, the white waterfalls on the mountains in the distance rushed down, and gathered into the river at the foot of the mountain, and the originally calm river water slowly rushed up.

Zi Yang and Su Rui hurriedly ran towards Lao Wang and the others, and when they got closer, they saw Lao Wang carrying Xiaoli on his back, and the dashing brother was carrying the equipment of the three people.

Zi Yang saw that Lao Wang was already tired and panting, and hurriedly took Xiaoli over and carried it on his back, and Su Rui also took some of Brother Xiao's luggage.

"Hurry up, the bridge deck is going to be flooded!" Ziyang urged everyone.

A group of several people ran towards the river.

"Xiaoli, how are you?" Ziyang asked anxiously as she ran.

"My feet hurt so much!" Xiaoli said with tears in her eyes.

After running across the bridge, Ziyang's speed gradually slowed down - after a rush of running, his strength began to be exhausted, and his legs trembled violently.

Although Xiaoli only looks like about ninety pounds, it is really difficult to run like this on her back, Ziyang gasped loudly.

The rain clouds finally caught up with them, and the pouring rain instantly drenched them in soup, and they couldn't see anything clearly in front of them, and the march became even more difficult.

"I'm coming!" Lao Wang slowly recovered a little bit of strength just now, took Xiaoli over, everyone quickened their pace, and after a cigarette, everyone finally rushed back to the camp in embarrassment.

At this time, the entire Qinhan Village was already shrouded in torrential rain, and the raindrops were almost connected into a line, hitting the leaves and the ground with a rattling sound, and the sky and the earth were hazy.

Lao Wang gently put Xiaoli on the bed, sat on the ground, and looked up at everyone.

"Hey, where's Blackie?"

Zi Yang was stunned for a moment, and secretly thought in his heart: "Yes, what about Xiao Hei who went out to fight rabbits?" Why haven't you come back yet? ”