After the body is incinerated, only part of it is handed over to the family to take away, and the rest is disposed of as the dregs of the incinerator. The master remembers very well that when he was cleaning the slag, this little thing fell out of the remaining slag.

All the evidence had to be handed over to Gu Yao, and this thing was not shown to other personnel.

At this moment, Gu Yao was holding this thing in his hand, this was a small pin, which could be pinned to the collar, the whole body was silvery-white, the shape was like a few twisted letters, and it was like a rose bone, the shape of this pin Gu Yao was very familiar, he had seen something similar, the magnetic key to open Professor Xia Heqing's safe, it was this shape.

Gu Yao once inspected the material of the magnetic key and found that it was a special alloy, which was very light but very hard. These two properties surprised the expert who examined the metal, saying that he had never seen it at all. Gu Yao refused the expert's request for further inspection, and secretly sealed the magnetic key.

It's really surprising that this kind of thing actually appeared in Yang Wei's ashes now.

This shape should represent the logo of a certain organization, Gu Yao was well-informed, but he had never heard of such an organization, and he pondered and put things away.

Zhou Qingyu was not idle, he took Su Keke to a place that no one expected, that is, the post office.

In the years when Yang Wei was known as Ou Xinran, the means of communication were still very backward, there were no mobile phones at all, and even landlines were rare, and people who made long-distance calls were either officials or had to go to the post office to make expensive pay calls.

Letters are a more common way of communication, but the speed of ordinary letters is very slow, and manual delivery, registered mail is faster, and it will not be lost, but it is required to register the delicate information of the sender and the recipient, otherwise the post office will not accept business.

Zhou Qingyu checked that Yang Wei was in Donghai City for several years, all the registered mail records in Donghai City, if Yang Wei sent the letter, she could forge the identity information, but the receiving address could not be forged, so the letter sent to Yang Wei would definitely be registered.

Zhou Qingyu showed his ID, and the staff of the post office led him into the warehouse where the registration books were kept, and pointed to a stack of registration books, "There is time in the book, you can check it along with it!" ”

Su Keke didn't expect that the previous archival work was like this, and the stacks of registration books were almost on the roof!

Seeing Su Keke's appearance, the staff pointed to the ladder in the corner, "Use it when you take the file book!" ”

Zhou Qingyu and Su Keke began the boring work of searching for registration. Speaking of which, Zhou Qingyu's method is very simple, find the information of Yang Wei's letter in Donghai City, and then go to the address of the sender to find clues.

This method sounds clumsy, but it was a common detection method at the time.

Tarzan is responsible for delivering food to the two of them, while liaising with other groups. Every time he entered the warehouse, he would see such a picture, Su Keke and Zhou Qingyu were sitting side by side on the pony, both with their heads down, quietly looking at the registration book in their hands. The sun shines through the small window, and the faint light shines on them, and the years are quiet, like a picture scroll.

This work is very boring, however, Zhou Qingyu found clues in the mountains of archives. It was a record from 1974, and there was a registered letter from Anshan, Liaoning Province, and the recipient said that Dongfeng Plant Technology Branch Ou was happy to receive it.

Ou Xinran is a pseudonym, except for the radio, letters were the only means of communication that could contact her at that time, according to the time, the person who wrote this letter should know that Ou Xinran is Yang Wei's pseudonym.

In the sender's column, it reads Liaoning Anshan Du Peixing.