At Ye Yunyang's request, several items were quickly delivered, namely glass jars, candles, pale yellow kraft paper, and a small bottle of medicinal powder.

The glass jar is more than 30 centimeters in diameter and about 50 centimeters high, made of pure and colorless glass, with high transparency, and a matching lid, made of the same material, which fits perfectly with the tank.

Ye Yunyang tried it, and the sealing of the glass jar was very good.

He picked up a piece of brown paper, laid it on the table, drew two vertical and horizontal lines with a pen, divided the paper into four equal parts, and pressed all five fingers of his right hand on it in the upper left corner.

Then, he smiled and said to Lei Shaoyuan: "Your Excellency, please follow what I did just now, press the five fingers of your dominant hand on it, you can choose the position at will, but don't repeat it with me." ”

Lei Shaoyuan didn't know what he wanted to do, but he did it anyway, and he chose the lower left corner.

Then, Ye Yunyang made a gesture of invitation to the deacon: "It's your turn, the practice is the same as Dean Lei." ”

The deacon snorted lightly, and the word disdain was written all over his face, if it weren't for Lei Shaoyuan taking the lead, he would definitely not do it, although he didn't know what Ye Yunyang's purpose was.

He selects the upper left corner of the vellum paper and presses down the five fingers.

Ye Yunyang expressed his satisfaction, and was about to reach out to pick up the kraft paper, when he suddenly pointed to Wang Dang and said, "There is still a position, don't waste it, then you can come!"

Wang Dang frowned, he had always thought that this matter could not involve him, but it was not difficult to see from Ye Yunyang's previous actions that he had been suspected.

But even if it is, what can it be, there is no evidence to say that no matter how much it is in vain, can it be that by pressing a fingerprint on brown paper, you can see who is the culprit, don't joke.

Of course he didn't believe it, so he walked over with a straight face, and in order to show his composure, he put his entire palm in the lower right corner of the vellum paper and pressed it vigorously.

Ye Yunyang shrugged, picked up the brown paper and said, "Everyone, the time to witness the miracle is coming, you had better keep your eyes open, so as not to regret missing a certain detail." ”

After speaking, he half-rolled up the kraft paper and put it into the glass tube upright, carefully moving the position to avoid the paper touching the wall of the tube.

Then, he took a spoonful of powder from a small bottle and put it in the bottom of the can, closed the lid and placed it on a rack made of wire. Next, he lit the candle and placed it under the shelf, aiming it at the brown powder at the bottom of the jar.

As the temperature rises, the brown powder begins to evaporate and becomes less and less abundant.

After more than ten seconds, the powder was completely gone, and the color in the jar was slightly heavier than before, and then something strange happened, and clear fingerprints appeared on the originally smooth kraft paper.

Everyone's eyes widened, and even Lei Shaoyuan, who thought he was well-informed, was startled, what was going on?

In fact, it is very simple, it is just a fingerprint obtained by using iodine vapor fumigation, in Ye Yunyang's previous life, this was just a simple experiment in the chemistry class of middle school students.

Human skin secretes trace elements such as oil, salts and amino acids, and because iodine dissolves in oil and forms brown marks, it can show fingerprints.

It's a simple, yet practical method that can find fingerprints left over a period of months.

"This ...... What's going on?" the deacon asked in surprise.

Ye Yunyang glanced at him and said, "You just need to know the answer, as for the principle, I don't bother to explain it to you, and I have no obligation to explain it to you! Of course, if you don't believe it, you can compare it through the glass tube to see if there is any difference with your fingerprint." ”

The deacon couldn't ask for it, so he stretched out his hand and walked over, just looked at it, and said excitedly, "It's different, it's completely different!"

"Please, the fingerprints printed on the vellum are reversed, you look at your fingers in reverse, you don't understand such simple common sense, I doubt how you became the boss of the library, was it nepotism, or did you spend money to go through the back door?" Ye Yunyang said sarcastically.

The deacon blushed, and after the reverse comparison, he never spoke again.

"Who else wants to compare, Dean Lei and Senior Wang?" Ye Yunyang made a gesture of invitation again.

Lei Shaoyuan shook his head: "Although I don't know what the principle is, I still believe that it is real." ”

Wang Dang naturally didn't have anything to say, and stood there with a thoughtful expression.

Ye Yunyang smiled: "Since everyone has no opinion, let's move on." ”

After saying that, he opened the lid of the glass tube, put the tin box inside, and added a small spoonful of iodine powder before closing the lid.

After the heating of the candle, the iodine powder volatilized smoothly, and the fingerprint marks on the iron box were clearly displayed, in this process, Ye Yunyang said: "The longer the time, the more blurred the fingerprints will be, and the more clear and clear they will be, all that are clear and complete are basically left recently! In addition to the fingerprints of me and Dean Lei, I believe there are also the fingerprints left by both parties to the transaction, as well as the fingerprints of the person who framed me." ”

Having said this, Wang Dang became nervous, and the iron box was taken from his uncle Wang Wenyao and brought to the library, that is, his fingerprints were left on it.

The deacon, on the contrary, was relieved, he had never touched the tin box, and felt that he could stay out of it.

Lei Shaoyuan was old and refined, and he had already guessed the purpose of Ye Yunyang's doing, he walked over, and said while comparing them: "These fingerprints are mine, these are yours, this ...... It's ......"

Ye Yunyang pointed to the lower right corner of the brown paper: "Take a closer look, whether they are exactly the same." ”

Lei Shaoyuan looked at it very carefully, nodded and said, "At least three finger prints are the same, basically you can be sure, there will be no mistakes." ”

Ye Yunyang turned his head to look at Wang Dang: "Senior Wang, now it's your turn to explain, why is there your fingerprint on the iron box?"

"I ...... This ......" Wang Dang was so anxious that he sweated, and he hesitated for a long time, explaining: "This method is not credible, how can I be sure that this is my fingerprint, maybe you found someone with a similar hand shape to me, and framed me." ”

"I framed you?" Ye Yunyang smiled: "Please, did you think about it before you spoke, it was you who reported me, and then this iron box that appeared, now it has become me framing you, do I know you?" Also, there are many people with similar hand shapes, but everyone's fingerprints are different, not to mention the Divine Realm, which has a population of only more than 20 million, even the Holy Heaven Continent, which has billions of people, cannot find people with the same fingerprints. ”

Wang Dang gritted his teeth and quibbled: "You are talking nonsense, the world is so big that there are no wonders, what is impossible for two people to have the same fingerprints......"

Ye Yunyang looked at him with a stupid gaze, and Lei Shaoyuan did the same, sighing and said: "Wang Dang, how did you get admitted to the Alliance Academy, you won't be a exempt student, right? Why don't you even know the most basic common sense, if there are people in the world with the same fingerprints, then what is the point of pressing the fingerprints when signing the contract, even if you are a child of a family, pampered since childhood, and pampered when you grow up, you should always know this bit of common sense, right?"

Wang Dang was not only speechless, but also blushed.

Lei Shaoyuan shook his head and said disappointedly: "Our students are so unbearable, it seems that we have to suggest that teachers focus on exempt students during the year-end assessment, lest you guys who don't learn and don't know how to ruin the reputation of the college." ”

Even if he was humiliated by Ye Yunyang, he was ridiculed by the dean in person, Wang Dang couldn't wait to find a crack in the ground to get into, and his face was as red as a monkey's fart.

Taking advantage of your illness to kill you has always been Ye Yunyang's fine style, and he chased after him and said: "Wang Dang, you haven't explained yet!"

Obviously, if he can't come up with a reasonable reason, Ye Yunyang will not give up, and Lei Shaoyuan will not spare him.

"This ...... Fake, maybe I touched it inadvertently before, what can an iron box mean?" Wang Dang bit back: "You said more than once just now that it is not used to hold banned books, what does it have to do with me?"

Ye Yunyang sneered: "If you don't see the coffin, you won't shed tears, I will make you completely dead, the iron box can have nothing to do with the banned book, then let the banned book speak for itself!"

He arched his hand at Lei Shaoyuan: "Dean, please borrow the forbidden book for use, if Wang Dang's fingerprints also appear on it, see how he explains." ”

"Yes. Lei Shaoyuan handed him the forbidden book.

Wang Dang was even more nervous, his face was covered with sweat, and his legs were trembling.

Ye Yunyang put the book into the glass tube and said: "Wang Dang, you still have a chance to take the initiative to admit it, once I put it in, you know very well what the result will be...... Well, it seems that you chose to be a hard bone, I appreciate it!"

He put the banned book next to the iron box, the glass tube was full of volatile gas of iodine powder, and as soon as the lid was closed, clear fingerprints appeared on the cover of the banned book.

After some comparison, Lei Shaoyuan's face became sunken, and he said coldly: "Wang Dang, how do you explain?"

Wang Dang's fingerprints also appeared on the cover, which shows that he not only touched the iron box, but also looked through the banned books.

Poof!

Wang Dang knelt directly on the ground and said: "Lord Dean, all students are in a daze for a while, and they frame their juniors with banned books, please see that I am a child of the Wang family, I have never violated the school rules for more than two years, just let me go!"

Lei Shaoyuan said angrily: "Sure enough, it's you! Use such despicable means to deal with junior classmates, you are so vicious, do you have the courage to admit it, Ye Yunyang gave you a chance a few times just now, why didn't you admit it, now that you know how to plead, don't you think it's too late?"

The deacon's eyes moved, and he felt that he should quickly put himself away, otherwise he would have to eat and hang up with the Wang Dang, and hurriedly said: "Dean, he was deceived by his position! He said that someone stole books, and Ye Yunyang was stopped by his office, but he didn't expect to be used by the Wang Dang, and almost wronged a good person, this is my dereliction of duty, please punish you, I have no complaints." ”

Lei Shaoyuan glanced at him and snorted: "I'll talk about your matter later, this dean has to deal with this madman first, the academy attaches so much importance to the moral education of students, how can there be such a scum!"

Wang Dang began to kowtow: "Dean, please give the student a chance, it is not easy for the student to enter the Alliance Academy, if he is expelled, what will he do in the future?"

Lei Shaoyuan sneered: "You also know that it is a shame, so why do you want to do such a dirty thing?" Wang Dang, this dean is too disappointed in you, forget it, you might as well give you a chance, if you are willing to confess the source of the banned book and other things, I will reduce the punishment for you as appropriate, there is only one chance, how to answer you have to think about it, don't let the opportunity slip away like just now." ”

As soon as he heard that there was an opportunity, Wang Dang still cared so much, and said in a loud voice: "The forbidden book was bought by my uncle at a high price to deal with Ye Yunyang, and the deacon is my accomplice, I spent money to buy him and let him stop Ye Yunyang from searching for the forbidden book......"

It can really be described as pouring beans from a bamboo tube, and in order to save himself, this guy directly betrayed his uncle Wang Wenyao and the deacon together.