Chapter 200

Zhao Jianguo held the Shuang Baotai as he came down the ladder, his feet just touching the ground, one child in his arms moved, gave a hum, and buried his face in his shoulder. The other little hand still gripped his collar, fingertips specked with ash from the fallen fireworks.

He steadied himself, gently patted the children's backs twice. The courtyard grew much quieter; the fireworks had stopped, the wind had died, only the string of tin wind chimes at the wall corner occasionally tapped and sounded.

Just then, his chest felt warm.

It wasn't hot, nor a jump, but a sudden warmth seeping from inside his clothes, as if someone had slipped a sun‑warmed cloth bundle into his pocket. He glanced down; no one noticed him. Dong Xu was still tidying the ruler and drawings on the podium, while Su Qing came out from the kitchen direction holding a tea tray.

Zhao Jianguo reached into his pocket and felt the Terminal. The Screen lit up, a line of text appearing: 【Check‑in Successful, reward "3D printing core structure diagram" generated, please retrieve.】

He didn't rush to take it out; first he turned and lifted the Shuang Baotai up, making sure they were sleeping soundly, then slowly drew out a rolled sheet of paper. Not large, a bit wider than a cigarette pack, but it felt heavy in hand, its surface covered with Fine Lines like the texture of old xuan paper.

He unfolded a corner, and the moonlight fell just right.

The lines were dense as a spider web, yet each was crystal clear, corners smooth without burrs, junction points seeming able to move. In the center was drawn a three‑dimensional gear set, layered, the outer ring marked "output shaft", inside also bearing annotations—not numbers but a string of Symbols—but he instantly understood: this was a power‑transmission structure, its precision far beyond what could be made now.

"What's this?"

The voice came from beside him.

Zhao Jianguo looked up; Dong Xu had come over at some point, holding an oil lamp, its shade slightly askew, the flame flickering. He stared at the paper, his eyes widening.

"Where did you get this?"

"Just got it." Zhao Jianguo said, "The System gave it to me."

Dong Xu put the oil lamp on the ground, crouched, his finger hovering above the paper, afraid to touch. "This… this isn't hand‑drawn, is it? Look at this angle—it can project the slots on the back and mark depth. Our factory's technical section struggles to draw three‑view diagrams on tracing paper; this thing… how is it made?"

Zhao Jianguo folded a corner and said softly, "It's called a 3D diagram, not for people to look at but for machines to read."

"Machines read it?"

"Right. In the future there will be a device called a 3D printer; following this diagram, it can directly print parts."

Dong Xu stared, silent for several seconds. He reached out to touch, then pulled back, finally saying, "If it could really be made, the old transmission boxes at the Steel Rolling Factory could all be replaced."

Zhao Jianguo nodded, about to roll up the diagram, when Su Qing walked over.

She set the tea tray on the stone table, lifted a cup and handed it to Dong Xu, then glanced at Zhao Jianguo's child in his arms. "Time to go inside; tomorrow we still have to take the kids to kindergarten—if we sleep too late we won't get up in the morning."

Zhao Jianguo answered, "I'll head back."

Su Qing didn't linger, turned and walked toward the Main Hall, steps light so as not to wake the child. Passing the patent wall, she casually steadied the projector stand; the line on the wall "Everyone can teach, everywhere can learn" flickered, then steadied.

After her silhouette entered the door, Zhao Jianguo looked back at Dong Xu.

"This must not be passed around casually." He said, "If we can't make it now, it would only cause trouble."

Dong Xu nodded: "I understand. Just the two of us knowing is enough."

Hardly had the words finished when a howl came from afar.

"You wait! My brothers won't let you off!"

The voice was hoarse, with an echo, as if coming from beyond the high wall. Zhao Jianguo frowned, recognizing it—Xu Da Mao.

He didn't speak, but his hand moved to his pocket. The Terminal trembled, and the Screen automatically popped a red box: 【Warning: Fluctuations in the signal of the Speculator Group's remnants detected; coordinates locked to the outskirts of the Northern Prison; advised to activate Level‑One protection plan.】

Dong Xu also heard the howl, his face changing: "He still dares to shout? Fifteen years locked up isn't enough."

Zhao Jianguo quickly rolled up the diagram, slipped it into his inner pocket against his chest. "He alone isn't scary; what's frightening is if someone outside is backing him."

"Who?"

"I don't know." Zhao Jianguo said quietly, "But the System Alarm and his shout happened almost simultaneously—too coincidental."

Dong Xu stood, the oil lamp's light casting half‑light, half‑shadow on his face. He stared toward the prison direction a moment, then said: "Two days ago, at the factory gate I saw a stranger wearing a Zhongshan suit and glasses, asking about everything, specifically probing your family's affairs."

Zhao Jianguo's eyes narrowed: "When?"

"Three days ago, around four in the afternoon. I asked who he was looking for; he said he was from the Education Bureau, here to inspect the teaching achievements exhibition. But he had no documents, no introduction letter."

"Then what?"

"I told him to go register at the office; he left and never showed up again."

Zhao Jianguo fell silent for a few seconds, then raised his hand and patted Dong Xu's shoulder: "From today on, be more careful coming and going. Keep the diagram matter under wraps for now."

"I know." Dong Xu lifted the oil lamp, "Should we inform Teacher He?"

"Not for now. She's with teacher‑training students, who can't reach the core technology. Let's first get a grasp of the situation."

Dong Xu nodded, lifted the lamp and turned to leave, but stopped halfway. "Jianguo, you say… could someone already have started researching the things we're making? Like the problem‑solving machine, or stationery design?"

"They've been at it for a while." Zhao Jianguo looked at him, "We just don't know where they are, nor what they intend to do."

The two exchanged a glance, then said nothing more.

The wind rose again, setting the wind chimes tinkling. The projection on the wall flickered, showing the latest data: nationwide, twenty‑seven counties and cities have applied to introduce the Siheyuan teaching method's support kit.

Zhao Jianguo lowered his head to look at the child in his arms—one still asleep, the other murmuring indistinct dream talk.

He was about to head indoors when the Terminal shuddered again.

Not an alarm, but a new prompt: 【Detected acceleration of the 1985 technological shift trend; advised to pre‑position in the civilian manufacturing sector, prioritizing the development of miniaturized, modular production technology.】

He hadn't even gotten to view the details when Dong Xu suddenly turned back.

"Right," he said, "Just now, while I was putting things away, I found a sheet of paper tucked under the experiment table, as if someone had slipped it in. I didn't move it, fearing to leave fingerprints."

Zhao Jianguo halted immediately: "What paper?"

"It looks like a rough sketch of a watch‑shaped object, with a numeric display window on it."

"Numeric display?"

"Yes. And beside it was a line of small text—'Smart Learning Terminal prototype concept'."

Zhao Jianguo's heart skipped a beat.

He hurried over, with Dong Xu leading him around to the back of the experiment table. A panel of the tabletop had loosened; a fingertip could pry it open. Inside lay indeed a sheet folded into a triangle, its edges a little dirty, as if someone had pinched it for a long time before stuffing it in.

Zhao Jianguo put on the cloth gloves he carried, carefully took it out, and unfolded it.

The diagram wasn't finely drawn, but the structure was clear. Below the watch face were drawn the battery compartment and circuit‑board location; on the back there was also an antenna design. The functional description read: real‑time sync of teaching content, voice prompts for wrong answers, automatic logging of study progress.

This is no ordinary invention.

This is aimed at their system's knowledge base.

He closed the paper, his face darkened.

"Anyone can draw this drawing?"

Dong Xu shook his head: "Ordinary people don't even know what 'synchronous teaching' is, let alone design circuit layouts. This person knows his stuff."

"Moreover, he knows what we're doing." Zhao Jianguo folded the paper and put it in his inner pocket, "This is not right."

He raised his head to look at the sky, the moon was half-covered by clouds; the prison direction in the distance fell silent, that earlier roar as if it had never happened.

But he knew, the matter wasn't over.

He stood in the courtyard holding the child, Dong Xu stood beside him holding an oil lamp, neither of them moved.

The wind chime sounded again.

Zhao Jianguo's hand pressed against his pocket, where two sheets of paper were attached—one from the system, the other of unknown origin.

Outside the Courtyard Gate, deep in the Hutong, Footsteps approached from afar, stepping on the blue stone road, not fast, but never stopping.