The train driver in the courtyard

It is a consensus of our time that electric trains will inevitably replace steam trains.

Just like the sleeping dragon in the east, which will one day awaken, the road may be winding.

But it will inevitably happen!
The new electric train standard has caused a huge stir abroad.

Domestic newspapers such as Renren Daily and television stations have also frequently given it prominent coverage.

"Warmest congratulations on our country's new electric train standard becoming a universally accepted standard!"

"This signifies that our railway industry has achieved a breakthrough, catching up with and surpassing the magnesium industry!"

"We call on all sectors to learn from Comrade Li Aiguo and the comrades who participated in the formulation of standards..."

Inside the study, the superiors were very pleased as they looked at the report submitted by the railway department.

"Comrade Li Aiguo is a talented person."

"Yes, especially considering that both the big brother railway and the little brother railway disagreed this time, the standard was still passed unanimously, which further demonstrates the value of the standard that Li Aiguo came up with."

Leader Teng, standing to the side, couldn't help but sigh with emotion.

"Tell me, we originally just asked this kid to build trains for the subway, but he quietly produced such a significant achievement."

Leader Teng's words were a bit too Versailles-like, but the higher-ups didn't care at all.

The higher-ups had been keeping a close eye on the matter and were naturally aware of the commotion at the meeting.

"This further demonstrates the patriotic comrade's ability and vision!"

Yesterday, I received a report from Lao Chen from the border region. The batch of drugs that Li Aiguo brought from the pharmaceutical institute played a very important role in South Asia.

Li Yunlong is making rapid progress; perhaps it won't be long before he secures access to the South Asian seas.

Upon hearing this, Leader Teng's eyes lit up.

Taking control of a seaport in a battle means completing a strategic division, which is equivalent to winning half the war!
In addition, it also opened up a vital transportation artery, allowing supplies to be replenished via sea freight in the future.

The situation in the South Asian conflict has become completely clear.

However, Leader Teng knew that these were all highly confidential matters, so he did not pursue the matter further and smoothly steered the conversation back on track.

"Comrade Aiguo has made another great contribution this time. Shouldn't we give him some reward?"

When it comes to rewards, even the higher-ups are a bit worried.

The rewards for the last supercomputer and P4 research institute haven't even been distributed yet, and now there's another world-class standard?

The higher-ups knew that Li Aiguo, like them, didn't care about personal gains or losses.

But things that need to be done should still be done, and rewards and punishments should be clearly defined to set a good example.

But what should be given?
At this moment, the assistant stepped forward, gently poured tea, and handed it to him, but hesitated to speak.

The superior noticed the assistant's expression and asked with a smile, "Xiao Zhao, what are your thoughts? Just say it!"

This isn't really an idea; I just heard that the national advanced worker selection is about to begin.

"Our patriotic comrade invented the electric train and made so many contributions; doesn't he meet the award criteria?"

The assistant spoke tactfully, expressing his own opinion while leaving the decision-making power to the leader.

The superior nodded: "I had completely forgotten about that."

Comrade Aiguo had previously received the title of National Model Worker, but at that time he received it as a worker.

This national advanced worker award focuses more on scientific research and technical positions, which I think is great!
It's settled then.

This was tantamount to making a direct decision, and the assistant immediately took out a notebook and wrote down what the superior had said.

The superior then looked at Leader Teng: "What has Comrade Aiguo been busy with lately?"

"The main focus is on the renovation of the Beijing subway."

Also, several companies in the Iron Alliance are very interested in our railway construction and would like to send a delegation to visit. What do you think...?

Leader Teng took the opportunity to ask for instructions.

The superior stood up: "Guests are guests, after all."

"I understand." Leader Teng nodded.

As a guest, if you obediently accept the host's arrangements, you will be treated to good food and wine.

If they have any ulterior motives... sorry, then they're unwelcome guests, and all they'll get is a shotgun!
of course.

The key to striking the right balance is also quite important.

……

Li Aiguo did not expect that the higher authorities would approve the visit requests of several Iron Alliance members so quickly.

"So, they can come to visit next week?" Li Aiguo looked at Section Chief Xing with slight surprise.

"According to the ministry, we can visit, but we have to bypass the classified area. Patriot, this matter still needs to be handled by you." Section Chief Xing explained the ministry's idea.

In addition to being a means of transportation, the Beijing subway is also a nuclear, biological, and chemical defense project, containing a large number of weapons and supplies storage points, all of which are classified.

"Don't worry, I know what to do."

Li Aiguo stood up to leave.

Old Cat is currently conducting an investigation at Shichahai, and no one knows what the results are.

"Wait a minute."

Section Chief Xing called out to Li Aiguo and handed him a form.

"Fill this out."

Li Aiguo took the form, glanced at it, and was immediately stunned.

He had filled out similar forms before, when applying for awards.

"Section Chief...this..."

"You're really lucky, kid! You've been named a National Advanced Worker this time!" Section Chief Xing was also excited for Li Aiguo.

It's important to know that this title is a national-level honor on par with the title of National Model Worker.

No one in China has yet been able to win both of these major awards at the same time.

As for whether he can be selected, Section Chief Xing is not worried.

Not to mention that the ministry's tone was already quite certain.

Take the things Li Aiguo did, for example; it's not an exaggeration to call him a National Advanced Worker.

Li Aiguo hadn't expected the higher authorities to be so generous this time.

How to do?
Of course, I took the form and filled in my name on it.

He then handed the form to Huang Shuxian in the Education Office, which would then apply on his behalf, as per the prescribed procedure.

It was past 1 p.m. when Li Aiguo arrived at Shichahai on his motorcycle.

Today is Tuesday, and most people are at work in the factory. There aren't many tourists in the lake.

Several elderly people were strolling under the shade of trees in the park, fanning themselves with palm-leaf fans.

Children played happily on the shore, creating a peaceful and idyllic scene.

Li Aiguo parked his motorcycle in a secluded spot and strolled all the way to the vicinity of Yinding Bridge.

I almost burst out laughing after just one glance.

Several young men in sanitation worker uniforms were seen rowing a small wooden boat, painstakingly cleaning up trash under the Yinding Bridge.

The one in the lead, wearing a tattered straw hat and covered in sweat, is none other than Old Cat.

The old cat was now somewhat exasperated.

They arrived at Yinding Bridge in one morning and searched the surrounding area several times.

They even retrieved broken shoe soles from the bottom of the water, and cleaned up all the surrounding trash, but still found nothing.

"Could it be that Comrade Patriot's speculation is wrong?"

The old cat looked up and saw someone smiling at him from the shore; it was none other than Li Aiguo.

"You guys keep looking here, I'll be right back."

The old cat gave a word of advice, then quickly brought the boat to shore and jumped ashore.

He pulled Li Aiguo to a quiet corner and explained that they had gained nothing so far.

"Are you sure you've searched every single place thoroughly?"

“Absolutely certain! Look over there, we’ve already cleared out two huge bags of trash!” Old Cat pointed to several large sacks that were about to be moved away, his face looking rather grim.

No wonder, cleaning up trash in that stuffy, humid place under the bridge on a hot day is no easy task. Not only do you get covered in sweat, but you also get all dirty.

At this moment, the old cat seemed even more dedicated than a real cleaner.

"Find a cleaning uniform, I'll go take a look."

Li Aiguo did not distrust Lao Mao and his team's search capabilities.

Rather, if Dieter really wanted to hide something deadly, his methods would be extremely secretive and would not be found through a conventional search.

Old Cat had already contacted the security department of Shichahai and asked them to send a security officer.

A short while later, a set of cleaning uniforms was quietly delivered.

Li Aiguo put on his uniform, wore a straw hat, and picked up a long pair of clips.

You know what, it actually looks pretty convincing.

As soon as he boarded the boat, it swayed and rocked as it approached Yinding Bridge, and Li Aiguo immediately understood what the Third Uncle had said earlier.

The water flow under the bridge is quite rapid, and many hidden rocks have been exposed.

Thankfully, the old cat rowed carefully; a novice would probably have capsized.

In addition, this was against the current, and by the time they finally reached the area directly under the bridge arch, Old Cat was already panting heavily from exhaustion.

The area under the bridge is perpetually shaded and cool, never seeing sunlight.

The only unbearable thing was the fishy smell; even with a thick cotton mask, it still gave me a headache.

Li Aiguo took a breath, looked around, and finally his gaze fell on a flat bluestone.

This place doesn't look strange, except it's too clean.

It was so clean it looked like it had been washed with water.

“Rinse. Maybe it’s not water.” Li Aiguo stroked his chin.

After Li Aiguo arrived at the location, he neither retrieved the trash nor knocked on the brick joints, but instead kept staring at the bluestone wall inside the bridge arch.

The old cat was a little puzzled.

"Patriotism, this bluestone wall is perfectly sealed, there's no hidden compartment to hide anything, there can't be any problem."

The other crew members on the ship echoed this sentiment.

"Yes, Comrade Li, we have already carefully tapped all of them with wooden hammers, and we did not hear any hollow sounds, nor any loose stones or gaps."

"The most basic requirement for this dead mailbox is that it must have enough space to hold secret letters."

"How about we go check out that rocky beach to the east? Maybe Dieter hid the secret letter under one of the rocks."

Li Aiguo shook his head: "Yamamoto and his men were under our close surveillance the whole time. The only blind spot where they could briefly escape our sight was under this bridge."

Therefore, this is undoubtedly the best location for Tibetan esoteric messages, without exception.

Everyone was stunned by these words.

How could a place with no gaps and no possibility of hiding a physical secret be the best place to hide a message?

That doesn't make sense.

However, for an experienced veteran agent like Old Cat, his heart skipped a beat.

He understands a logical principle.

Once you've eliminated all the impossible options, the one that remains, no matter how incredible, must be the truth!

"Xiao Wang, steer the boat to the left and keep it steady!" Old Cat made a quick decision, directing a team member to paddle the boat close to the stone wall.

Li Aiguo stood up and touched the stone with his hand.

Yinding Bridge was first built during the Zhengtong period of the Ming Dynasty and is a standard single-arch stone bridge in the old capital.

Originally, the entire structure was built of massive bluestone blocks. In 53, the southern half of the eastern bridge railing was knocked down by an out-of-control car. It was later extensively repaired, and the railing was replaced with a white marble wall.

However, the bluestone from the Ming Dynasty is still preserved under the bridge arch.

"bluestone."

Li Aiguo seemed to have thought of something, and his eyes lit up: "Team Leader Cat, immediately send someone to the nearby epidemic prevention station or hospital to get a bottle of bleach, and be quick!"

"Bleach? What do you need that for?" Before Old Cat could even speak, a young team member couldn't help but ask curiously.

Old Cat turned to the team member and gave him a severe dressing-down:
"Enough with the nonsense! The train driver tells you to carry out a task, so go and do it immediately! That's the rule!"

The team member shrank back immediately after being reprimanded.

Suddenly realizing this was a major case, he quickly jumped onto a spare small boat nearby and rowed towards the shore.

The team member was quick and efficient, going out fast and returning just as fast.

Just as Li Aiguo was carefully examining the texture of the bluestone, the team members returned, covered in sweat, with a glass bottle of bleach.

Everyone on the ship held their breath, staring intently at Li Aiguo's every move, eager to see what tricks he could pull off with the bleach he usually used for disinfection.

This thing was used to bleach and fade homespun cloth before liberation, and it was also said to have sterilization and disinfection properties.

But what does this have to do with arresting Dieter and solving major cases?
Amidst a multitude of gazes filled with both doubt and anticipation.

Li Aiguo calmly added some river water to the glass bottle, gently shook it a few times, and allowed the powder to dissolve completely.

“That’s right, this is the concentration.” Li Aiguo looked at the liquid in the bottle with tiny bubbles rising to the surface and nodded in satisfaction.

Then he found a strip of cloth, dipped it in bleach, and wiped it on the bluestone.

One second, two seconds... The surface of the bluestone was wet and showed no reaction.

"Patriotism," the old cat couldn't help but say.

"Don't rush, let the bullets fly for a while," Li Aiguo said in a deep voice.

What are you waiting for?

The old cat was completely bewildered, but he still suppressed his anxiety and stared intently at the smeared bluestone.

The next second, Old Cat's pupils suddenly contracted, his face changed drastically, and he was so shocked that he almost jumped up on the small boat!

The once bare bluestone surface now displays a series of numbers.

These numbers are written very neatly and in small size, clearly indicating that someone deliberately used special methods to write the code on them!
"Could it be invisibility potion?"

"That's not right! Aren't contact lens solutions usually written on paper or fabric? Besides, I've never heard of contact lens solution developing when it comes into contact with bleach!"

"Stop talking nonsense! Write these numbers down word for word!"

Old Cat called out, and the team members, who were all well-trained, immediately picked up their notebooks and began to take notes.

Li Aiguo wasn't idle either; he continued to use a strip of cloth soaked in bleach to smear it on the nearby bluestone.

Sure enough, similar numerical codes were found on the cross-sections of two other bluestone pieces.

Li Aiguo only stopped after he had covered all the surrounding stones with the smear and confirmed that no new numbers had appeared.

By this time, the team members had recorded all the numbers, checked them repeatedly, and handed them to Li Aiguo.

Unbeknownst to them, they had come to regard this train driver, who rarely appeared at the weather station, as their pillar of support.

"It should be a secret message. Take it back and decipher it."

Li Aiguo put the notebook into the file bag and stood up.

"Aiguo, what exactly happened? You've got me so worried, tell me quickly!" At this moment, Old Cat's curiosity was completely piqued.

He had worked in meteorology for so many years, and this was the first time he had ever seen such a dead mailbox.

If Li Aiguo hadn't brought in bleach, even if the entire bridge had been demolished, it still wouldn't have been found.

While the team members were cleaning up the trash used for camouflage, Li Aiguo smiled and said, "Actually, it's quite simple. It's just a little bit of basic chemistry knowledge."

This type of bluestone belongs to marine sedimentary limestone, and its interior contains trace amounts of ferrous and manganese salts as a coloring matrix.

Under normal conditions, these substances are colorless, but when they encounter specific oxidizing agents or acid-base color-developing agents, they undergo an oxidation reaction, turning into yellowish-brown or brownish-yellow traces.

"There aren't many reagents on the market that can be used to make this specific oxidant. In order to avoid exposure, Dieter also has to ensure that this reagent is very easy to obtain and will not arouse suspicion."

Therefore, I speculate that there is a high probability that they used 'ferrous sulfate'.

"Green vitriol? What's that?" the old cat exclaimed in surprise.

Li Aiguo nodded: "The chemical composition of ferrous sulfate heptahydrate is ferrous sulfate heptahydrate, which is very common."

They can be easily obtained from Chinese medicine shops, dye houses, textile factories, and even some chemical plants, making it impossible to trace their source.

Dieter wrote the code on the bluestone using ferrous sulfate solution; once the water dried, it was invisible to the naked eye.

"The simplest and most effective way to make the ferrous sulfate that has seeped into the stone re-develop is with bleach."

The calcium hypochlorite in bleach provides a strong oxidizing environment, which allows the code to be revealed.

These words, spoken in a simple and profound way, left everyone on the ship speechless.

They certainly knew about invisibility potions; after all, weather station agents often used traditional methods like rice water and iodine.

But this is the first time I've heard of such an advanced invisible technique that can use trace elements in geological rocks to write directly on bluestone!

Most importantly, this potion is readily available.

Dieter's methods were undeniably brilliant.

Unfortunately, they encountered a train driver.

The old cat looked at Li Aiguo with a different kind of gaze.

Just how much stuff is in this guy's head?
Not only do they understand advanced mechanical and scientific research theories, but they are also proficient in these obscure chemical knowledge.

Even a dead mailbox can be identified at a glance!
"Did you all prick up your ears and hear that? From now on, you should learn more from the train driver!"
Don't always think that being a meteorologist only requires good marksmanship.

Without a wealth of knowledge, one would be completely outmaneuvered by someone as intelligent as Dieter!

Old Cat spoke to the team members.

The team members hesitated for a moment, then nodded.

They wanted to, but it seemed a bit too difficult.

Considering that deciphering the secret letter was urgent, Li Aiguo did not waste any more time.

Afterwards, Lao Mao directed the team members to row the small boat to the shore, pretending that they had finished cleaning up the trash.

As they were docking, a few elderly women who were taking a stroll happened to pass by. Seeing the several sacks full of garbage, they praised the young sanitation workers for their high level of awareness.

"Auntie, we're all working to build socialism. There's no such thing as a high or low position. We're all serving the people!"

Li Aiguo replied with a smile, then packed his things and left quickly.

Right now, at this very moment.

In a secluded courtyard on the outskirts of Beijing.

An old man with a hunched back was slowly sharpening a kitchen knife.

The cleaver was sharpened to an extremely thin edge, and under the afternoon sun, it emitted a chilling glint.

But he still seemed to think it wasn't sharp enough, so he lightly scraped the blade with his thumb and frowned slightly.

In his subconscious.

It seems that only a knife capable of severing a person's head with a mere swing can truly satisfy his requirements.

"Father, you sent a message asking me to come back. What happened?"

The wooden gate to the courtyard was pushed open, and a young woman in work clothes walked in, looking somewhat impatient.

"Dad, why did you send someone to call me back in the middle of the day? What's the emergency? There's still a ton of work to be done at the factory!"

The old man didn't even look up, but simply said, "Let's talk inside."

As he spoke, the old man casually tucked the kitchen knife into his belt at the back of his waist, slowly stood up, turned around, and walked into the dark room.

The young woman was stunned for a moment, and a chill inexplicably rose in her heart as she looked at her father's unusual behavior.

She hesitated for a moment, then gritted her teeth and followed him inside.

The door was closed, shutting out the bright sunlight.

The woman grew increasingly anxious and spoke in a low voice.

"Dad, as you know, our locomotive factory has been extremely busy lately."

The order came from above: we must immediately go all out to manufacture new electric trains, and even the workshop foreman won't approve leave..."

"Ningzi, our chance has come."

The old man interrupted her.

The young woman, who was already furious at being called back at the last minute, was so startled by the old man's abrupt and unexpected words that she stood up abruptly.

"Father...you, what did you say?!"

The old man said slowly, "I just received a top-secret order from the country. After lying low for so many years, the mission has finally arrived."

After these words were spoken, the room fell into a deathly silence.

The young woman fell silent for a full two minutes before speaking in a trembling voice, "Dad...we're doing quite well now!"
I am currently a level three worker in the factory, with a stable monthly salary of over forty yuan. I can also get an extra supply of refined white flour every month with coupons!

If I try a little harder, maybe I can get recognized as an outstanding employee and continue to improve...

Dad, so many years have passed, let's just forget about the past and live a peaceful, ordinary life...

"Snapped!"

Before she could finish speaking, she received a hard slap across the face.

The old man used all his strength in that slap.

The woman screamed in surprise as she was hit, stumbled and fell onto the hard bed next to her, blood immediately seeping from the corner of her mouth.

The woman covered her rapidly swelling and reddened cheek, looking at the old man in front of her with fear.

Over the years, the father and daughter have depended on each other for survival, living in anonymity and enduring countless hardships, but the father has never laid a finger on her.

The old man became like a stranger, his emotions running high.

"Idiot! Ningzi, how many times have I taught you this since you were little?"
Our Black Feather family is a prestigious and renowned family over there!
Noble blood flows in our veins!
Our ancestors were warriors who swore to serve the empire to the death, and felt the greatest honor in sacrificing themselves for the empire!

The old man pointed at the woman's nose, suppressing his voice as he roared wildly.

"You've actually been bought off by a few pounds of flour and a few dozen yuan?"

They actually plan to betray Tianhuang?!
How can you face your deceased mother?!

"No, Father! That's not what I meant..."

The woman turned pale with fright and knelt down in front of the old man with a thud.

"But Father, the checks in the capital are too strict now!"

If we're exposed, we're definitely doomed!

"Dad, please listen to me this once, can't we just live a good life?"

"Hmph, how could those idiots be a match for me? Ningzi, don't worry, your father has already made arrangements."

The old man calmed down a bit and helped the woman up.

"This time, the bereaved family will send someone directly to meet with us. As long as we successfully complete this sabotage mission, we will be able to return to our homeland in glory with the commissioner!"

The woman's expression softened considerably upon hearing the name of the "Order of the Deceased."

She often heard her father mention that the descendants of the deceased were incredibly powerful, which would greatly increase their chances of winning.

If she can really complete the mission... she won't have to work so hard as a factory worker anymore.

Even when I return to my hometown, I can still see those beautiful cherry blossoms.

Desire and wishful thinking gradually overcame fear.

The woman bit her lip, her eyes gradually hardening.

"Father, tell me, what should I do?"

(End of this chapter)