I lifted my waist and stood up all at once, and then carefully took two steps forward, feeling as light as a swallow, as if I had lost gravity.

"Well, does it feel like you're walking through space?" Seeing my surprise, the black bull said proudly: "As soon as I came in, I found the peculiarity of this place, so I quickly put you down to rescue, otherwise, according to the little brother, I have to drag you to the black shadow before I let go." ”

I glanced at Gao Moli, who had already taken out a wolf-eye flashlight, took a picture of the black shadow, and said, "I'll take a look." With that, he held the triangular sword in one hand and a flashlight in the other, and turned to float towards the black shadow.

I took a photo, and found that the black shadow really absorbed the light, and at a distance of more than 20 meters, the black shadow was still pitch black, and I couldn't tell what it was.

"Be careful! If the situation is not right, come back quickly, and we can escape from the soft door again! I told Gao Moli's figure.

Gao Moli didn't look back, and he didn't know if he heard it.

"Don't worry, I don't think that black shadow should be a living thing, otherwise it would have been awakened a long time ago." Gu Yixin said, pointed to the transparent isolation layer above his head, and continued: "What I'm worried about is this thing, it's extremely hard, will it trap us here?" ”

"Isn't there a soft door? But strange to say, what is the material of the soft door? How is it that only through people can not seep into the water? ”

After that, I looked up and saw that the iris was more than twenty meters high from us, like a transparent sky, enveloping us in this strange space.

The soft door we entered was like a soft transparent silicone, trembling and refracting countless spots of light under the illumination of the light beam.

"Let's go and see." I beckoned and walked towards the soft door. At this moment, we seem to be space explorers who have disembarked from the Apollo spacecraft, and we are in the vast universe, and we can travel two or three meters away with just a small step.

The black bull thought I was moving slowly, and he bounced upwards like marbles, hitting his head on the transparent barrier, and he scolded and touched his head in pain.

"I can't eat hot tofu in a hurry! Come, let me see what kind of substance this glass cover is, and it can withstand the brute force of our black bull! ”

As I spoke, I stepped forward and tapped my iris with my hand, and the sound was exactly the same as the sound of striking the glass. Through the refraction angle of the beam, I estimated that the iris was at least half a meter thick.

I wondered more and more: Is this really a glass barrier? However, more than 2,000 years ago, such advanced glass-making technology could not have been possible, and even today, with the development of technology, it is not easy to build such a huge layer of glass protection in the waterhole at the bottom of the cave.

How did this underground miracle come about?

"Lao Su, do you think that if this thing is released, will it be included in the world's top ten discoveries? I'll have to keep a souvenir so that I can mention my name when the archaeologists find out in the future! The black bull said that, he took out a steel arrow and squeaked and carved words on the glass layer.

I glanced at it, and it was the words "Niu Yuanchao visited here" that he engraved, and I laughed: "Look at the words you wrote, the strokes are messy, the structure is scattered, and you stretch out your arms and kick your legs one by one, so that archaeologists don't know that you haven't graduated from elementary school." ”

"You don't understand, the more ugly it is, the more difficult it is to understand, and the more difficult it is, the more you will study it. I don't know if archaeologists still think it's an oracle bone inscription! The black bull looked proud.

I didn't bother to talk to him, so I stepped back, came to the bottom of the soft door, and reached into the soft door, only to feel that the palm of my hand was inserted into the rubber jelly, soft and cool. I swung my arm and swiped it left and right, and the marks quickly returned to their original shape. I tried to grab a handful, but the semi-solid thing was so slippery that with a little push it would slice through between my fingers.

"Not good! This soft door seems to be getting smaller! Gu Yixin rushed to my side, shouting in panic as he pulled half of my arm out of the soft door.

I hurriedly looked up, and saw that the soft door that had been the size of the Eight Immortals Table was like a rapidly frozen lake, and had become only the size of a manhole cover, and the freezing continued, and I could even hear the "click" of those semi-solids being frozen.

The soft door was quickly frozen, becoming exactly like the surrounding glass barrier. I sighed in my heart, if it weren't for Gu Yixin's quick hand to pull my arm out, just a moment and a half later, I am afraid that half of my arm would have to be permanently sealed here.

"What's going on? How did the soft door freeze? Could it be that the entire glass barrier used to be soft? I asked, with a pause.

"I seem to know the reason for the formation of this glass barrier." Gu Yixin thought for a moment and slowly explained: "According to the description of the murals in the first cave, during the Western Zhou Dynasty, a bottomless hole appeared in this mountain out of thin air, and I think that the formation of this deep cave is likely to be a meteorite outside the sky. The meteorite smashed into the mountain with a very high combustion temperature, and the geological structure in the mountain is mostly limestone and quartz, these two stones melt quickly at high temperatures, forming a bubble wrapped around the meteorite, there is just a pool of water in the belly of the mountain, the water temperature is extremely low, so that the bubbles wrapped in the meteorite gradually cool, thus forming a protective shield made of glass. ”

Gu Yixin glanced at the soft door that had just condensed, and added, "Just now you stirred it with your arm, causing the surrounding air and cold air to enter it, and the previous soft door quickly solidified. ”

I thought about it for a while, and felt that Gu Yixin's explanation was very reasonable, and said: "In other words, this transparent isolation zone in front of us is really likely to be glass?" ”

Gu Yixin nodded and replied, "Yes, but this is not done by man, but by the miraculous creation of nature." ”

The black bull floated from the side, and when he saw that the soft door had disappeared, he was stunned and shouted impatiently: "Now I don't care what the fucking material this broken cover is!" I just want to know, now that this soft door is sealed, how can we get out? ”

The black bull had been trapped in the glass cover of the thousand-year-old willow coffin before, and had already experienced the feeling of being besieged to death once, and now that he was trapped again, he couldn't help but feel a little panicked and afraid.

"There's a hole here!" Gao Moli stood on the black sphere, waved his wolf eyes at us, and shouted with a little surprise.

The black bull was like a toad, kicking his legs and running over first.

Gu Yixin and I followed closely behind, standing beside Gao Moli, only to see that this black sphere was indeed as Gu Yixin said, a meteorite that had been melted and riddled with holes.

There was a black hole in front of Gao Mo's feet, and the hole was as thick as the sewage drain in the city. I lay at the entrance of the cave and shone it in with a tactical spotlight, but it was pitch black, and I didn't know where it led.