Everything was arranged, and Zhang Mengqi and several people successfully climbed over the barbed wire fence with the help of ladders. At the other end of the www.biquge.info is a pine forest, and it is not difficult to tell from the thick fallen leaves on the ground that this place is rarely visited.

As soon as Zhang Mengqi's feet landed, Lao Xian bent over his waist and held a magnifying glass and began to study the bark of each tree. Just as he was engrossed in his research, a crooked-necked tree on the slope caught Zhang Mengqi's attention.

There is hardly any garbage under the other trees except for fallen leaves, but this one has a large number of purple bags scattered under it.

In order to find out, Zhang Mengqi walked over, and Zhang Mengqi's actions also aroused Xiao Jiao's curiosity.

As the distance gets closer and closer, the handwriting on the packaging bag gradually becomes clearer, and when the text information is clearly captured, a scene with its own mosaic instantly emerges.

"Shubiz condom." Xiao Jiao read out loud a string of small words on the bag.

"Xiao Jiao, your eyesight is really good, you can see such small words, admire, admire." Zhang Mengqi teased.

"I'm dizzy, there are so many, at least a hundred and ten, and it's all the same brand, this person is addicted, running to this place where no one comes to fight in the field?" Xiao Jiao picked up a branch and sighed while pulling on the ground.

"It's the tree." The old sage's voice came from above, and Zhang Mengqi looked up to see that he happened to be standing in front of the crooked neck tree and pointed to the bark of the tree, looking very sure.

"What? Is it such a coincidence? Zhang Mengqi walked quickly in front of Lao Xian in disbelief, and the scarred spike prints on the bark of the tree were shocking.

"You see, these marks should have been left by the suspect when he climbed last night, and they are still fresh." The old man reached out and placed the magnifying glass on top of the trace.

"Moreover, I have observed all the trees in this vicinity, and I can only see a few trees in the crime room, and there are no traces on other trees, so I can be sure that this is the tree that the suspect stepped on." Lao Xian added.

"Judging from the dense new and old traces on the surface of the bark, the suspect is not here for the first time, and he should have come here often." Zhang Mengqi walked around the trunk of the tree.

"Mengjiao, the suspect wore gloves when committing the crime, but in order to increase resistance when climbing trees, it is possible that he will not wear them, do you have a way to deal with the surface fingerprint marks of this tree?" Lao Xian pinned his hopes on it.

"I was already ready when I was in the unit just now." As she spoke, Zhang Mengjiao walked to the survey box and took out a large bottle of pale yellow powder from it.

"What is this?" Xiao Jiao's curiosity is always so heavy.

"This is a powder I bought from a Chinese medicine store, called pine pollen."

"Pine pollen? Why is it used? ”

"It is a traditional Chinese medicine, which is the dried pollen of many plants of the same genus, such as masson pine and pine tabuliformis, and its main use is to reduce inflammation and stop bleeding."

"Traditional Chinese medicine can also be used to extract fingerprints?" Xiao Jiao asked suspiciously.

Zhang Mengjiao smiled confidently: "Either trace science is a discipline that needs to be studied in depth, as long as you understand the special effects of pine pollen, you will not doubt it." ”

"Listen up." Xiao Jiao pinched his waist with both hands.

Zhang Mengjiao unscrewed the jar in her hand: "We know that what remains on the surface of the bark is mainly the sweat handprints of the skin of the fingers. ”

"Well, that's common sense."

"Pine pollen has a strong adsorption effect on the sweat handprints of the plant epidermis. When the pine pollen particles come into contact, the adsorption of the pollen cell wall, the water permeability and the hydrophilicity of the native protein contained in the fingerprint increase the molecular cohesion, so that the pine pollen is firmly adhered to the lines of the handprint. ”

Zhang Mengjiao looked at Xiao Jiao and added: "To put it simply, pine pollen has a soft spot for fingerprints on the skin of plants and has a certain affinity. ”

Xiao Jiao couldn't hear that she was teasing her, and "snorted": "Everyone will say that you have the ability to deal with the fingerprints on this crooked neck for me, I want to see if this pine pollen is so magical." ”

Zhang Mengjiao smiled slightly, did not answer, put on a mask and walked in the direction of the tree trunk.

Zhang Mengjiao took out a thermometer and measured the outdoor temperature, six degrees Celsius.

Seeing this value, I put the thermometer back in with confidence. The main reason for measuring the temperature is to rule out the presence of frozen fingerprints.

Now it is winter, because the sweat fingerprint also contains inorganic salt components, inorganic salts have a certain degree of water absorption, when the temperature drops below the freezing point, the fingerprints will freeze to varying degrees, and pine pollen in the fingerprints when they appear, it is necessary to ensure that the fingerprints can only be carried out in the liquid state, and the current temperature is obviously above the freezing point, so as to rule out my concerns.

The method of pine pollen to show fingerprints is very stupid, that is, it can be sprinkled simply and rudely, without any technical content, just a cigarette, the entire trunk was sprinkled with powder by Zhang Mengjiao, and then took out the inquest record book as a "fan", and removed the excess powder on the trunk, and more than a dozen handprints with yellow powder appeared in front of us.

"I can't see the lines of my hand at all, how can I tell them?" Xiao Jiao said the key. Because fingerprints want to identify people, they rely on some detailed features on the fingerprints, and due to the uneven bark, the fingerprints I processed cannot see any features at all.

Zhang Mengjiao raised her eyebrows, not worried about this at all. Then he found a ruler from the toolbox and began to measure the length of the palm prints and knuckle prints on the bark.

Several people looked at Zhang Mengjiao's actions curiously, not knowing what medicine was sold in the gourd.

After measuring all the data of palm prints, Zhang Mengjiao confidently got an answer.

"Brother Ming, all the fingerprints on this tree are all left by one person, and through comprehensive analysis, it should be the suspect. The suspect is a male, and his height should be about 1.75 meters, if we can find this suspect, I can analyze whether he is a suspect by the length of his knuckle prints. ”

"Really?" Xiao Jiao asked.

"It's actually quite easy to judge. First of all, the gender is judged by the size of the handprint, the man's palm is wide, the fingers are thicker than the woman, and there is a value to refer to, I just measured the full length of these palm prints, and judged that the suspect was a man. ”

"Secondly, knowing the length of the palm, there is a formula to calculate the approximate height of the suspect, and although the error exists, it is within a controllable range."

"Finally, I'm going to talk about the length of the knuckle. According to the normal understanding, we should know the small characteristics of the suspect's fingerprints before we can identify the person, but this is not absolute, you stretch out your palm. ”

Xiao Jiao followed Zhang Mengjiao's instructions and took off his gloves, revealing his fair and slender right palm.

"Have you ever seen horizontal knuckle lines on your fingers?"

"Well, yes, what's wrong?"

"Each of our fingers, except for the thumb, is divided into three segments by knuckle lines. And the length between these three segments, which is almost different for everyone, is a specific value. ”

"Oh, I see, you mean to say that although we can't see the lines of the fingers clearly, we can measure the length of the suspect's knuckle prints first, as long as we find the suspect, you can measure whether his value is similar to the value we have, so that we can determine whether he is a suspect or not." Xiao Jiao suddenly realized.

"Let me correct it, this can only confirm that this person is very suspicious of committing a crime, because the length of the knuckle print is not fixed like the fingerprint line, and it also has a lot of variables in it, such as the case of a dislocated finger joint, or a ruptured tendon in the finger, which will affect the value, so this can only be used as side evidence to assist in solving the case, not as direct evidence for conviction."

"Okay, you're amazing!" Xiao Jiao is willing to gamble and lose.