The flow of the dark river is vertical and horizontal up and down, because there is a slope and a gradient difference.

Suppose we compare two parallel metal plates to the two sides of a dark river, then the displacement current between the two sides of the parallel metal plate is the dark river, and the outlet is longitudinal and backward, and we row downstream in a small boat.

Due to the direction of the dark river, the actual path is in the direction of the slope, but does not affect the destination at the end point.

At this time, except for the two people who rowed, the rest of them did not speak, conserving their strength. I hung my head and couldn't help but feel a little interested in the construction of the boat.

We don't know what kind of wood the boat we rowed was made of, and it was very light and fast. And each of us has a foot chisel under our feet, just enough to put our feet into, and there is a fixed iron piece on it, which should be of great use.

As we paddled downstream, it gradually became darker and darker, and we could barely see the scene ahead by the light of the flashlight.

At this time, the old man at the bow of the boat shouted at the big man, Little K: "Don't row yet, there seems to be something in front."

When my uncle said this, our hearts suddenly became alert and we all looked ahead. I saw a pile of rocks looming on the river surface in front of me, crisscrossing each other. In the pile of rubble, you can see a long steel cable, embedded in dozens of boulders, leading to the front, and the steel cable is covered with hanging rings, one every half a meter.

The boat began to shuttle among the rocks, we didn't dare to relax at all, looking at the rings in the sky, we were all thoughtful, what is this ring used for?

It didn't take long for us to get out of the pile of rocks safely, and our vision suddenly widened, and the river in front of us was white and shrouded in mist, which was full of weirdness.

The old man passed the word to the big man and the little K, and the two nodded, and each stood on the side of the boat, holding the boulder beside him with both hands, keeping the boat from being moved by the current.

We stood at the bow of the boat and watched quietly, softly, slowly, the sound of the rapid flow of water came to our ears.

Uncle hurriedly flashed the flashlight and shone in the direction from which the sound came, and under the light, each of us couldn't help but take a sharp breath of cool air, and there was a "vortex" on the water in front of us.

If the boat approached and was suddenly stirred in, it would be so easy to figure it out.

Seeing this scene, each of us realized the seriousness of the problem in our hearts. The "vortex" that is now in front of us is likely to be a fatal obstacle, and we have no choice but to paddle it down.

My uncle didn't know when he started to smoke, the smell of smoke was particularly pungent, I raised my head, and saw my uncle's eyes staring at the rings in the sky.

Zhang Yu stood up violently, and his two hands just grabbed the hanging ring above his head, as if his uncle thought of something, and suddenly shouted at us, "Put your feet in the foot chisel".

Hearing my uncle's words, we seemed to see hope and acted accordingly. When the old man saw that we were almost done, he began to do it himself, and then motioned for the big man and the little K to row and go ahead.

Although the two of them had a little doubt, they did not stop in their hands. My uncle ordered us to stand up and keep our eyes fixed on the river ahead.

When we were about to approach the "whirlpool", my uncle yelled at us, "Grab the ring on the steel cable and move the boat over the water."

I grabbed my hand at the ring, and the first thing I felt was that my foot was strangled and my whole body was suspended in mid-air. Then, feeling the pressure on his whole body loosen a little, he looked back and forth, and gathered the strength of the seven of us to make the boat above the water. My uncle shouted to us behind him, listen to my orders, and put your hands on the rings in front of you, to be steady and fast.

Not only did I have to overcome my own gravity, but I also had to bear the gravity of the boat, and I felt a little physically exhausted, but fortunately, the range of the "vortex" was not very large. As we passed through the white mist, a pile of rubble appeared in front of us, and the other end of the steel cable was here.

I collapsed on the boat, looking at Zhang Yu who was sitting precariously, my eyes couldn't help but wonder, how did this guy practice with such good physical strength.

Before we could rest for long, the boat was hit by something, and if it hadn't been for the big man's experience, I would have been the first to fall into the river. When we came to our senses, we saw a black shadow in the water, moving from the bottom of our boat to one side.

Zhang Yu and I each took a slurry, and the big guy picked up the AK47 and shot at the black shadow.

After the gunshots passed, the surroundings suddenly fell silent. I cried out for joy, and there was a hole in the water not far ahead, just wide enough for the boat to enter, and presumably the exit was in it. There was no trace of surprise on everyone's faces, and they all moved their eyes to the side, and when I turned to look, my face suddenly turned pale, and I repeated a sentence on my lips, "How can this be?" ”。

A large number of black shadows suddenly appeared on the water surface at the stern of the boat, and the body of this black shadow could be vaguely seen about two meters long. My uncle ordered Zhang Yu and I to row quickly, while he and the big guy each stood at the stern of the boat with an AK47 and began to shoot at the river.

The entire surface of the river gradually turned red, and the pungent smell of blood came to my face.

Rumble!

It was as if a bomb had been thrown into the water, and the whole river began to boil, and countless black shadows came straight towards our boat, ignoring the threat of bullets from my uncle and others.

Our boat was hit so hard that in less than a minute, the whole boat was about to shatter. The old man turned to look towards the water hole, which was not too far away. The bow of the boat had already begun to sink into the water hole, and my uncle gritted his teeth and shouted to me: "Xiao Ke, come here and do this black thing, just let Zhang Yu row the boat alone."

Hearing my uncle's words, I grabbed my gun and walked to the stern. I don't know if I don't see it, and I'm shocked when I see it. This black shadow turned out to be a dolphin, and the dolphin at this moment looked hideous, desperately crashing towards the boat.

I lay on the stern side of the boat, picked up my pistol and fired at the water, and the hit rate was absolutely 100 percent. The big guy and the old man's gun don't know how many dolphins died.

The boat began to sink into the waterhole, and the dolphins became agitated, and the attack became more and more fierce. One of the dolphins leaped violently, its long tail brushing away the old man's gun. I hurriedly jumped forward and dragged my uncle forward, exposing myself to the dolphins' attack. I looked at the black and oppressed dolphin with wide eyes, and I woke up to the fact that I had just forgotten to defend myself by saving my uncle.

However, an accident happened, and when the dolphins saw me, they were like ghosts, and they rushed to the side in fright, and the pressure on the big man suddenly increased, and they looked at me with a glint in their eyes, and then handed over the robbery to their uncle and walked towards me.

I was still busy reacting, so I was picked up by the big guy, and before I could speak, my whole body was like a fan, being slapped back and forth by the big guy. Sure enough, it had a great effect, and the herds of dolphins just didn't dare to come forward, and the boats were completely in the water hole.

The big man had a smile on his face and gently put me down. I immediately fell to the surface of the water, retching, and my head was still dizzy. My eyes inadvertently glanced at the sludge on my arm, and I couldn't help but have a flash of inspiration in my mind, my uncle and they have all washed it off, but I haven't washed it off, can this sludge not only prevent corpse insects, but also prevent dolphins?

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