Chapter 118

The process of fixing the fingerprint can be basically divided into two steps. The first step is to make the fingerprint appear, and the second step is to fix the fingerprint.

In the era of prosperous science and technology, there are powder method, chemical reagent method, photochemical method and other methods to show fingerprints, while fixed fingerprints are from tape to photos.

However, Li Luoyang now has only fine toner and thin white paper in his hand. He scraped the toner from the charcoal pen and rolled it carefully with a roller. It is not known whether it can reach the standard of 500 mesh. Li Luyang vaguely remembers it.

The fine toner that can be blown away by the wind was carefully shaken on the tea cup by Li Luoyang, and then a very surprising scene happened. Most of the toner fell along the smooth surface of the tea cup, but some remained on the wall of the tea cup, forming round plans.

"This is the fingerprint?" Ren Haoyun tried to keep his eyes open. He was a civil servant and needed to read and write every day. In addition, the lighting level at night in this era was really poor, so his eyesight had already died. If he wanted to see the vague pattern clearly, he almost rubbed the tip of his nose against the tea cup.

In contrast, Mo Jiao's eyesight is much better. At a glance, she can see that the black marks on the tea cup are really like the lines on her fingers.

"But it's too vague."

"Don't worry. When shaking the toner, first blow it gently, then brush off the excess toner with this soft brush, and finally use this white paper, like me."

Li Luoyang wrapped a mouthful of tea, brewed it for a moment, and then ejected it at a height of two feet on the paper. The fine water mist settled down to wet the white paper, but there was no obvious water trace. Li Luoyang looked and felt that the degree of wetness was just right, so he privately printed a piece of white paper on the place with finger lines on the tea cup.

“LOOK！”

"What way?"

"It's nothing. You see, the fingerprint is left on the white paper. Now, please dip your right thumb with a little water. Yes, that's it, and then apply toner. Yes, print it."

According to Li Luoyang's requirements, Ren Haoyun left a clear black fingerprint on the white paper with his right thumb, while the fingerprint taken off by Li Luoyang on the tea cup is far from so clear. Fortunately, he can barely see the lines. The two fingerprints are arranged and placed in front of Ren Haoyun and Mo Jiao.

"That's good?" Mo Jiao looked at the white paper with fingerprints, and then looked up at Li Luoyang with confidence.

"Yes, this is the whole process of extracting and identifying fingerprints. When you find a murder scene, you first need to block the scene, and then carefully check where fingerprints are easy to leave on the scene. You can always find fingerprints with ground toner or chalk and a soft brush."

"And then?"

Ren Haoyun asked as he compared the two fingerprint patterns.

"Then, the suspect's fingerprints are extracted for comparison. Of course, the safest way is the murder weapon. If the suspect's fingerprints on the murder weapon and the location and direction of the fingerprints are consistent with the characteristics of the wounds caused by the murder weapon, the criminal can be locked basically. However, if the suspect's fingerprints are not extracted from the whole murder scene, it can not be said that the suspect must be innocent , he may have committed a crime with gloves on. "

"As like as two peas, not take it seriously, Luoyang, you are so amazing!" Hao Yun was somewhat excited, as if he had picked up a treasure. But Mo Jiao shook his head in a reluctant way. "It is not so useful, it can not help us find the suspect."

"Jiao Jiao, we already have a lot of ways to find suspects. With the fingerprint verification method of Li Luoyang, the possibility of unjust, false and wrong cases will be greatly reduced. After the six doors, we don't have to bear the bad names of 'neglecting human life' and 'being beaten into a trick'. Good, very good."

"Since Lord Ren thinks this method is good, shall we fulfill the agreement first and let my honest uncle out first?" seeing that Ren Haoyu agrees so, Li Luoyang's hanging heart finally fell to the ground, so he said slowly.

"No problem. We'll follow your method tomorrow. Ah, I understand now. Why do you want us to block the Inn room where Li Baoshan was killed, just don't want others to destroy it."

"The crime scene," Li Luoyang added for Ren Haoyun.

"Yes, yes, the crime scene, the crime scene. Oh, Luoyang, now not only Jiao Jiao wants to pull you into our six doors, but even I have this idea. How, as long as you nod, I can promise you now."

Be a six door hawk?

How can Li Luoyang be a hawk dog of the six gates? Even if the six gates are the "emperor's Pro army" who directly obey the emperor, Li Luoyang heard the most words in his previous life, that is, accompanying a king like a tiger. Besides, the reputation of the six gates and the Royal guards is the same as the stones in the toilet. It's disgusting to imagine.

"Why, aren't you happy? Hum, we have the right of compulsory recruitment. Believe it or not, uncle Yun will let you join immediately with a piece of paper?"

"I'm still a child!"

Being forced by Mo Jiao, Li Luoyang has no choice. Li Luoyang has a strong heart and is willing to be aggressive. No, he should be coquettish. Find Ren Haoyun to coquettish!

Perhaps because he just got the fingerprint extraction method, Ren Haoyun was in a very good mood. He didn't care that Li Luoyang rubbed his nose on his long sleeve and kindly rubbed Li Luoyang's hair. "Well, Jiao Jiao is kidding you. We can force recruitment, but we can only recruit Ding Nan. You really don't meet the conditions."

"Shit, I'm scared to death!"

Let Hao Yun say this, Li Luoyang finally breathed a sigh of relief. He didn't cry or make any noise. He quickly wiped the tears on his little face and took out a stack of written paper from his arms. The paper described how to prepare toner. Originally, he thought he wanted to monopolize the production of toner, so that the next six doors could only be purchased from him. Later, he thought about it, This thing is not high-tech either. People can get it out by just studying it. Why bother to offend others.

"I've already said what I should teach. Lord Ren, you should keep your word. I'll go back and wait for your good news!"

Li Luoyang doesn't want to stay in this place for a minute. It's a long dream. He'd better leave early. What's more, he still has a big project in his hand, a big project involving the national economy and people's livelihood of the Wu Zhou Dynasty, energy-saving stove.

"Zhu Donghe, how can Li Luoyang's head be so easy to use?"

No one expected that on the roof next door, Wu Xinyi and Zhu Donghe witnessed the process of extracting fingerprints almost all the way. Although they could not detail every step and sentence, it was by no means easy to make the four grade officials of six doors smile.

Wu Xinyi peeked aside, but Mo Jiao didn't respond at all, which shows that their martial arts are not at the same level.