Nan Zhiqiao took out a black waterproof flashlight from his pants pocket and shone it around the cave, and finally the light was fixed on the wide area on the side of the cave, and said, "Let's go, go there first." ”

Nan Zhiqiao has a habit, every time he goes out, if he drives a car, he will prepare some emergency items in the car, and if he goes out on foot, he will also carry some with him, Ye Zhenzhen was infected by Nan Zhiqiao, coupled with the life and death experience in the forest park last time, he also developed this habit, and also took out a black emergency waterproof flashlight from his pocket.

The three of them waded to the shore, and Ye Zhenzhen first treated the wound on Xiaobin's arm briefly, but fortunately, the wound was not deep, only a slight abrasion, and the blood quickly coagulated.

At the same time, Nan Zhiqiao used a flashlight to observe the terrain of the cave.

This underground cave is oval-shaped, and the underground river gushes out of the underground rock crevice on one side of the cave, and the water flows into a large pool in the center of the cave, and finally flows along the perennial erosion of the river channel.

Above the cave, in addition to the big pit that has just collapsed, there are many thin streams of water seeping down from different corners above, it seems that the rock layer above the cave has been eroded by the grass flowing water.

Nan no Qiao's flashlight suddenly stopped, and the light stopped in the direction of the underground dark river exit.

Next to the underground river, there is a low passage half a person high, and there are obvious traces of artificial excavation when you look at the rocks around the passage.

Nan Zhiqiao was wondering here, how could there be traces of artificial excavation in this natural cave? Ye Zhenzhen, who was behind her, suddenly shouted: "Senior Nan, come and see, there are snails here!"

Unexpectedly, a snail was found in the underground river, and Nan Zhiqiao and Zhang Xiaobin came to Ye Zhenzhen's side at the same time.

At this time, Ye Zhenzhen was leaning over the edge of the central pool of the cave, her flashlight shining on the bottom of the water, and her face was almost touching the surface of the water.

The shore and the bottom of the water are clearly illuminated by a flashlight, a layer of dense ephedra black snails are attached to the shore, and there are more snails under the water, stacked on top of each other, and the size is different.

Nan Zhiqiao and Ye Zhenzhen's two flashlights shine in the water at the same time, in this large pool of the underground cave, in addition to the snails, there are many wild small fish, under the reflection of the light, the small fish are in groups, and the snow-white fish scales are a little dazzling.

Just now, Zhang Xiaobin felt that his feet were itchy from being gnawed by something in the water, which should be a school of fish in the water.

Zhang Xiaobin exclaimed: "This is actually a fish hole, and there are so many snails, this should be the source of snail breeding." ”

Ye Zhenzhen is not interested in small fish, but more concerned about the snails that caused the outbreak of schistosomiasis, where did so many snails come from in such a hidden underground cave?

Ye Zhenzhen muttered to herself: "Such a dense snail feels like it is artificially bred." ”

"No way. Zhang Xiaobin immediately retorted, "No one eats snails, they are worthless, who will be idle and have nothing to raise this kind of thing, besides, this underground cave, others can't enter it, if we don't fall from it, no one knows that there will be a cave here." ”

"No, someone has been here before us. Nan Zhiqiao said quietly, and at the same time, moved the flashlight light in the direction of the exit of the underground dark river.

Next to the underground dark river, a half-human-high passage leads to nowhere.

There were obvious traces of artificial excavation around the passage, and Nan Zhiqiao walked along the shore to the front of the passage and focused the light of the flashlight on the excavated stone wall.

The stones on the stone wall seem to have been chiseled by some kind of tool, and the fracture surface is grayish-white, which is the color of the inside of the limestone, and the rest of the cave, although it is also limestone, is covered with a layer of dark green moss because of its age, and the tentacles are slippery.

Judging from the color of the stone wall of the passage, this passage has just been excavated, and it should not take more than two months.

One side of the passage is adjacent to the channel of the underground dark river, and there should have been a passage here, judging from the color change of the stone, but the original passage was very small, and the passage was artificially excavated and enlarged, allowing a person to walk forward.

The passage in front of him was the only way out of the underground cave, and Nan Zhiqiao waved his flashlight, signaling the three of them to move forward from here.

Nan Zhiqiao took a flashlight and was the first to bend down into the passage, Ye Zhenzhen followed closely, and Zhang Xiaobin walked last.

The passage became wider and wider the further you went, and after walking down more than a hundred meters, the passage became more than one person high, but the width became narrower and narrower, allowing only one person to pass sideways, and after walking a few dozen meters, a bright light appeared in front of you, and the rumbling sound of water was heard.

Soon, the three of them walked out of the crack passage and appeared in front of them a waterfall falling from the sky.

Drilling out of the crack and going around the back of the waterfall, the three of them stood on the bank of the pool under the waterfall, in front of which was the familiar canal, and above it was the grass where Grandpa Zhang's wooden house was located.

It turned out that the three of them went up to the grass above the waterfall from here, and then entered the underground cave from the cavity where the grass collapsed, and turned around along the passage of the underground dark river, and finally returned to the original point.

Because the sampling box was gone when the grass collapsed, the three of them did not bring specimens back, and on the way home, Zhang Xiaobin wondered that after living here for so many years, he didn't know that there was a passage behind the waterfall.

What's even more strange is that this passage is semi-natural and semi-artificial, I don't know who is so bored, digging a passage behind the waterfall, is it the villagers in the village? Does anyone know that there is an underground karst cave behind the waterfall, and there are many fish in this cave, it is a fish hole?

Zhang Xiaobin thought about it, and could only think of this seemingly reasonable explanation.

After returning to the village, Zhang Xiaobin told his father about the fish cave, and Xiaobin's father went to the village to ask other people, but the villagers said they didn't know, and in the end, they didn't figure out who dug the passage behind the waterfall.

I didn't inquire clearly, and Xiaobin's father didn't care, for the villagers, more places to fish is the most important thing.

Nan Zhiqiao notified the local CDC of the source of the discovery of snail breeding, and soon, the CDC sent someone to take samples for testing.

It was found that the snails in the underground cave also contained schistosomiasis, and the source of the schistosomiasis epidemic was found.

Everything was carried out in accordance with the requirements of blood prevention work, and the underground river in the cave was also put into the snail killing drug, and the source of the epidemic was solved.

——

The annual Torch Festival is fast approaching.

Although Zhang Xiaobin's family is of Han nationality, they have been mixed with various ethnic groups for a long time, and the customs have gradually been assimilated, and the torch festival has also been lived.