Several times, Cha Wenbin failed again, looking at his anxious appearance, Jia Daoshi suddenly thought of something, and reminded Cha Wenbin: "If you insist on seeing this mirror as a translucent mirror, you might as well look at the front from the back of it, and I will let them put the light together and move it slowly." ”

"Where is there a look in the mirror to look at the back," said the fat man, "don't talk nonsense and whimsical old man." ”

"It was Wen Bin's words that reminded me," Jia Daoshi said, "Luomen once found a magic mirror, which is an object from the Western Han Dynasty, and its greatest miracle is that when the bronze mirror is pointed at the sunlight, the reflected light spots, there will be an image on the back of the mirror." Later, our Premier Zhou Enlai saw this magic mirror in the museum, and he was puzzled, and it took ten years to solve this mystery. ”

"And then, did it crack?" The fat man asked.

Daoist Jia nodded and said, "The principle is said to have been clarified, and I heard that it is the product of the joint efforts of man and nature. ”

"There's such a thing." Feng Qiyun said: "This kind of craft was completely lost in the Song Dynasty, and the Tang Dynasty's "Ancient Mirror Records" contained: "Bearing the sun, the back is painted, and the ink is in the shadow, and the fiber is not lost." In "Dream Creek Writings", it is recorded that "the world has a light to learn from the sun, and the back lines and two crosses are all visible on the wall of the house, which is clear." "There is indeed a saying in many historical documents that there is a translucent mirror, in the era of the invasion of China by the Eight-Nation Alliance, there was a coalition army that stole such a mirror from the Forbidden City, and Western scientists have also studied the principle of this mirror, but from ancient times to the present, from the middle to the outside, no one has given a correct answer to this eternal mystery, no one has used experimental methods to confirm their guesses, more precisely, no one has really copied the mirror that is exactly the same as this translucent ancient mirror."

Regarding this point, the author specially checked the data, and the translucent mirror is the residual stress generated in the mirror body when it is subjected to the action of radial pressure P and bending moment M. Since the mirror body is a convex body, the mirror body has a tendency to arch under the action of residual stress. However, the mirror body has a certain stiffness, only when the mirror body is thinned to a certain extent, and the bending stiffness has been significantly reduced, the action of this radial pressure and bending moment makes the mirror body deform and arch to the mirror surface obviously.

When the mirror body is arched, the deformation of the thin part is greater than that of the thick part, that is, the convex degree of the thin part is greater than that of the thick part. This results in a fully convex mirror with varying degrees of convex protrusion in various parts of the translucent mirror surface. When the copper mirror is grinding, the stiffness of the mirror body decreases at different rates, and the deformation of the mirror body becomes more and more different. The difference in the curvature of the mirror is becoming more and more significant, and it becomes a mirror that is more and more uneven. This difference in curvature of the mirror corresponds to the ornamentation of the back of the mirror, so the image of light and dark reflected in sunlight is the image of the back of the mirror.

In the explanation and definition of the scientific community, there is such a sentence: the ancient copper mirror production process using the principle of concave and convex light transmission is very complicated, the material selection is strict, the grinding cycle is extremely long, and it takes a century to naturally form the surface protective layer "glass profile", so the light transmission mirror has always been a palace article, and it is difficult to become popular......

Feng Qiyun looked at Cha Wenbin and said, "I remember, you once said that there were some hallucinations when you saw this mirror, and I now suspect that it may be a translucent mirror, so you might as well give it a try." ”

A few miner's lamps began to adjust the angle, and Cha Wenbin carefully observed and adjusted the front and back sides of the mirror, but unfortunately, whether it was the light spots projected by the mirror or the back of the mirror, there were still no magical changes, as if this was an ordinary copper mirror, which did not have any magical power.

Cha Wenbin was a little deflated, half-squatting on the ground with his hands scratching his hair, there was a sense of frustration, the loss of so many fresh lives brought him too much pressure!

"Maybe it's not on this statue," Feng Qiyun comforted, "Maybe it's the wrong light, our miner's lamp is too bright, if you use natural light, maybe it's different." ”

"Natural light?" The fat man pointed to the dark patch around him and said, "This place has not seen sunlight for thousands of years, besides, who would want their bones to see the light." ”

"That's not right!" Cha Wenbin suddenly got up and said: "I remember, Lu Liang once told me that they once beat the top of their heads when they intercepted the stream, and it is estimated that it was later resealed, how could such a secret underground palace be easily penetrated by them at that time?" ”

"Dick!" The fat man immediately shouted: "I'm afraid I will have to work hard for you, you have to climb up and look for the top position to see if there are traces of artificial landfill, if there is, I have some explosives here, and it will be blasted away for his mother, so I will find a way out, and we can go out to study and study and come down again at any time." ”

At the top, dozens of meters above the ground, Ye Qiu could only put on the battle again, going up the rapids waterfall, after experiencing the previous tension, it seemed that everyone thought that this matter was just a pediatric for him. The fact is that no matter how difficult it is, Ye Qiu will never say it in his mouth, who can guarantee that the impact of the bone separation will definitely be able to resist it?

Climbing up the waterfall again, Ye Qiu began to search for the vault with a miner's lamp, and sure enough, he found an obvious rock fault layer five or six meters away from him. After Lu Liang blew up this place, he found that the water flow was too large to intercept the flow, so he sent people to re-use boulders and earthwork to fill it, and after a few decades, this piece of artificially loosened place has begun to have plants taking root, and the thick root system has penetrated out along the cracks of the year, and the remaining parts of the soil are the thickness of a thumb.

There was no place to borrow force from here to that part, if he had to put the explosives in place, Ye Qiu had only one choice, and that was to jump, jump five or six meters away in parallel, and then grab the only tree root that could be forced. There must be a premise here, the roots of the tree are enough to withstand the impact of the moment, and there is that he can hold it firmly at that moment, once empty-handed, he will fall into the deep pool again, a drop of tens of meters, although there has been one before, but who can not guarantee that he will be trapped by this complex underwater environment, or be carried into the dark river by this current and roll into an unknown place.

"This is too hanging," Cha Wenbin said, "Stone, you tell him to come down first." ”

"Come down?" The fat man shook his head and said: "It's not that I'm ruthless, it's that I have to send it when I am ready to fly, I have seen that distance, and I am at least fifty percent sure of the second child's skills, if we interfere below at this time, I estimate that it will distract him." ”

"That's right," Feng Qiyun added, "the more we can't mess with ourselves at this time, we have to trust him, but the question is how to get back if he ignites the explosives?" ”

"Jump down," said the fat man, "it can only be like this, and all the debris after the explosion will be smashed into the water, and the detonator detonating time is set at half a minute, and he needs to swim quickly to a safe place in this half minute, so this matter can only be done by him." ”

Ye Qiu didn't think about it so much, the location of the waterfall was extremely current, he was very embarrassed to barely stabilize his body, the distance of five or six meters was indeed not a big obstacle in normal times, but now that the water was pushing people forward, most of his strength had to be used to stabilize the balance of his body, and it was difficult to suddenly exert force in such a situation. Looking at the surroundings, he decided to change the way, he carefully grabbed the angular stones and began to look slowly towards both sides of the waterfall exit, after some searching, there was a small depression in the left position, and that was it!

His body began to stick tightly to the rock, and all the gaps that could be adhered to were used, and below was the rumbling water, and the more places he could exert his strength were two fingers and a little bit of the tip of his toes. It was with such a trace of adhesion that Ye Qiu began to move sideways towards the depression, his body kept trembling slightly, and he kept starting to blindly search for all the next steps that could be borrowed with his toes, which was the real frightening part to watch.

"What is he going to do?" The fat man asked, "This is too dangerous, Lao Tzu can see that his legs and feet are weak." ”

"The current is too big to exert force," Feng Qiyun said: "He must have enough space for himself to turn around, and then use the strength of his legs to take off, there is only one chance, if we fail, we can only go home." ”

When he encountered a place where he could not borrow his strength, the Cold Moon Knife was pierced into the crevice of the rock, and this was still a thousand choices to have a suitable point, and the hardships in it were not too described, and he finally stepped on the small depression. It was just enough to fit half a foot, and there was a slight slope downward, and it was the best position he could have nearby, and he was lying there panting like a gecko, trying to adjust his breathing.

The next thing is the point, Ye Qiu's posture at this time is facing the rock, he has to turn around to face the blast point, it is already rare to be able to lie on such an almost bare rock, and if he has to turn around, he just can't imagine how difficult it will be. Each move means that the strength of one arm is reduced again, and at the same time, the balance has to be tilted outward, Ye Qiu tried several times and found that it didn't work, so he planned to take a gamble, twist his body as hard as he could, and volley into the root of the blast point in a half-sideways position!