When he was in the mortuary, Lingyou handed over the wine jug and the deed of loan to Chonglou for safekeeping. After returning to Muyuan Building, Xie Xuan expected that Chen Chaoyan would not let Ling You bring these two things back for no reason, so he asked Chonglou to wrap the wine pot and the loan deed in silk cloth and put them in the wooden box next to the chaise longue.

Now that Chen Chaoyan wanted it, he asked Chonglou to take it out again.

Chen Chaoyan's extraction of fingerprints at the scene of the crime was originally only known in general theory, but not in reality. Now that she is in such a backward era, whether she can extract fingerprints from the flask and the deed of deed, she can only say that she will try it or try her luck.

Let Bai Shao push her to the window, hold the wine jug with a handkerchief, take advantage of the sunshine, and after checking it again, she took a few breaths in the position where fingerprints might be left. After that, he quickly borrowed the light and looked at the place where he was angry. No, the glaze is too rough and no fingerprints are visible.

Chen Chaoyan did not give up, continued to face the sun, and used the magnification function of the light screen to check next to each other. After failing again, she said to Chonglou: "Go to the bottom of the pot in the kitchen and scrape me some dust, and besides, prepare me a pen that I have never used." ”

After Chonglou went, Chen Chaoyan turned around again and instructed Ling Quan: "You take the danni and paper to ask Wang Da, after they went to Zhou's house in the morning, how many people have touched this wine pot and the deed of loan." But let everyone who touches them, let them press their fingers once, all ten, and remember to write their names under their fingerprints. ”

Ling Quan looked at Xie Xuan.

After Xie Xuan nodded, he walked quickly.

"I want to see if I can get fingerprints on this flask and the deed." Without waiting for Xie Xuan to ask, Chen Chaoyan took the initiative to spread out his palms and pointed to his fingertips to explain to him after asking Bai Shao to bring her a box of powder or flour, "Fingerprints are the lines formed by these uneven skins above, and everyone's fingerprints are different, and they will hardly change." If you can brush it out on the flask or the deed, then you can directly lock the murderer. ”

Xie Xuan spread out his left hand, looked at the fingerprints on his fingertips, and the corners of his mouth hooked imperceptibly. Fingerprinting is another word he has never heard of, and it is an unheard of method to solve a case. Lifting his eyes and glancing at the wine jug and the deed of loan in front of her, Xie Xuan didn't understand and asked, "If the fingerprints don't pass through the mud, they will also stay on the jug and the deed?" ”

"Of course. Theoretically speaking, there are a large number of sweat glands and sebaceous glands on the skin of people's fingers and palms, and as long as people are alive, sweat and sebum will continue to be discharged. Therefore, as long as the fingers or palms touch the object, there will be marks on the object. Such marks are divided into obvious lines, molded lines and latent lines. Chen Chaoyan explained in an endorsing manner, "Obvious lines are lines that can be seen with the eyes, such as handprints pressed with danni; The molding pattern is the fingerprint left on candles, semi-thin mud, etc.; Latent ......"

Chen Chaoyan held the wine jug with a handkerchief again, "That's it, there must be fingerprints on it, but it can't be identified with eyes, so it can only be made visible with the help of some means." ”

"Originally, the best carrier of fingerprints was the murder weapon. But because of the spasm of the corpse, the murder weapon was firmly held by Zhou Zhongcai, and the pollution was too serious, so he could only try this wine pot and the deed. ”

If the pot ash and powder or flour can really brush fingerprints, no matter whose fingerprints it is, then you can take them to the scene of the crime and slowly extract them where they may have fingerprints.

As for how to compare the fingerprints after swiping them...... Chen Chaoyan looked at the light screen.

The highest resolution that the screen on the market can carry is 4K, but the image of the light screen is definitely more than 8K, and even the legendary IMAX is 18K. Because the optical screen is infinitely enlarged and reduced, the image is still ultra-clear, so to speak, after calling it a super camera and unlimited storage, it can also be called a super magnifying and shrinking mirror.

In order to verify his words, Chen Chaoyan called up the video of his visit to Zhou's house in the morning, and after magnifying it twice, he rechecked it in the hope of finding one or two missing clues.

It wasn't until Chonglou took the pot ash and pen back that she withdrew from the light screen without finding anything.

The large iron pot in the kitchen of the county guard has not been scraped in years. Chonglou is very strong, and I don't know the purpose of Chen Chaoyan's pot ash, the scraped pot ash is all large or lumpy, and it can't be used immediately. Chen Chaoyan couldn't, so he had to let him go and find a clean stone mortar again.

After grinding the pot ash into a fine powder with a stone mortar, and sifting it through a fine sieve, Chen Chaoyan dipped the pot ash with a pen and flicked it lightly on the deed. Bounce back and forth several times until the ashes are evenly layered, and then she holds the pen again to remove the excess ashes from right to left.

While she was cleaning the ashes, Xie Xuan was standing beside her, while Chonglou and Bai Shao were standing at the back, and all three of them watched her movements.

"It worked!" Before half of the edge was swept out, two fingerprints appeared one after another, and Chen Chaoyan looked up at Xie Xuan excitedly.

Xie Xuan looked at the fingerprints on the loan deed, and then looked at her bright eyes, the idea of tying her to her side unconsciously grew crazy again. Hooking the corners of his mouth, Xie Xuanyan praised unsatisfactorily: "Miss Chen is really amazing!" ”

"It's good luck, too." Chen Chaoyan's mind was all on fingerprints, and he didn't pay attention to the mystery hidden in his words. After habitually humbling herself for a few sentences, she looked at the light screen.

On the light screen, two fingerprints are listed side by side, with clear lines. As long as Ling Quan brings back the fingerprints of Wang Da and the others, she is fully confident that she can immediately compare them, whose fingerprints are these!

Suppressing his excitement, Chen Chaoyan confidently began to sweep up the remaining pot ashes.

In the remaining pot ashes, thirty-eight fingerprints were swept out.

The fingerprints are concentrated on the left and right sides of the IOU, with only a few scattered ones falling in the middle. Looking at its shape, the left and right sides are the posture of holding the IOU to look at, and the middle few pieces are left by the writing IOU.

It is both a viewing pose...... In the same way, Chen Chaoyan swept out 41 fingerprints on the back of the deed.

The fingerprints on the front and back add up, minus the fifty-three fingerprints that overlap and cannot be distinguished, and there are still twenty-six fingerprints left.

The same is true for another IOU.

Chen Chaoyan looked at the fingerprints in the seventeen horizontal rows and ten vertical rows on the light screen, and after his eyes condensed for a moment, he brushed the fingerprints of the wine jug with powder. The flask is earthenware, and the black glaze on it is too rough. Chen Chaoyan changed the flour to powder, and after failing to brush out the fingerprints, he gave up regretfully.

Xie Xuan saw her movements and asked, "Can't you brush it out here?" ”

Chen Chaoyan nodded.

Xie Xuan looked at her, "Why?" ”

"The surface is too rough for the powder to adhere to." Chen Chaoyan explained casually.

Xie Xuan delved into it: "What do you have to use to brush it out." ”

Naturally, it was a chemical method, but there were no chemicals here, and with her strength, she couldn't make them herself. couldn't tell him in detail, so Chen Chaoyan simply said, "I don't know." ”

Xie Xuan looked at her with deep eyes: "You don't know either?" ”

Chen Chaoyan said 'um', "I haven't learned this." ”

Is it that you haven't studied it, or you don't want to say it? After Xie Xuanjing looked at her for a few breaths, his eyes fell on the IOU in her hand, "The fingerprints on the two IOUs add up to nearly two hundred, how do you plan to compare?" ”

"There are nearly two hundred, but only forty-nine of them can I identify." Chen Chaoyan pointed to the overlapping fingerprints, "I can't identify two or three or more fingerprints like this overlapping each other." Only this single fingerprint, which is not contaminated by other fingerprints and is still intact, can I recognize it. ”

Xie Xuan asked casually, "Is it that you can't recognize, or can't you recognize it?" ”

Chen Chaoyan glanced at him, "It's that I can't recognize it." ”

Not to mention the fingerprint analyzer that has been used by the criminal investigation department for a long time, let's say that many of them can not only use image processing technology to extract the clearest fingerprints, but also draw the incomplete fingerprints completely according to the unique feature points of the fingerprints. This kind of overlapping fingerprint identification work is just a separate fingerprint, which is one of the bases for drawing a mutilated fingerprint.

"Who can tell?" Xie Xuan got to the bottom of it.

Chen Chaoyan raised his eyes to look at him, and after a slight pause, he raised the corners of his mouth slightly, and said with some evil taste: "If there is no accident, in this world, no one can recognize. ”

In this world...... Xie Xuan's pupils shrank suddenly, and then asked quietly, "Is that in your world......"

Chen Chaoyan looked at the door: "Lingquan is back!" ”

After Xie Xuanshen looked at her twice, he also looked at the door.