Don't go to the moon, there are gods on the far side of the moon.

On the third day, Qin Lan took a sample from the scraped bottom of the grid.

It's not about taking wood.

It involves taking the temperature curve left on the wood.

"It's not getting cooler," she said. "It's been three days, and it's still only slightly warmer than the surrounding area."

"Like someone has just touched me."

"Yes," Qin Lan said, "It's like someone has been standing there the whole time, with their hand on the board."

Xu Wangshu looked at the curve and suddenly asked a question that no one had thought of.

Who wrote the message at the bottom of cell number 31?

"Lin Wangchuan?" Lu Chenggong said.

"No." Xu Wangshu shook his head. "The message in the forty-seventh square was written by Lin Wangchuan; I recognize it. The handwriting in the bottom square of the thirty-first square is different."

"Who wrote that?"

"I don't know," she said, "but I know who it was written for."

Everyone, look this way.

"This is for the person who comes after me," Xu Wangshu said.

"Which one is next?"

"Stand here, looking for the person whose name you are."

She magnified the curve.

The hottest point is not in the exact center of the grid.

It's located slightly to the left and slightly below.

That's where someone's elbow rests when they're writing.

"The person who wrote this line," Xu Wangshu said, "was not tall, was right-handed, and leaned forward while writing."

"You can tell from that?"

"Yes," she said. "Temperature doesn't lie. It remembers better than paper which board was pressed and how heavily."

Lu Chenggong stared at that spot and suddenly said, "This posture indicates that he was writing while kneeling."

Everyone was stunned for a moment.

"The grid isn't very high off the ground," Lu Chenggong said. "You can't reach it while standing, so you have to kneel down and lie on your stomach to write."

"Who would kneel in the counterweight chamber and write on the bottom of the grid?"

No one answered.

But Qin Lan's breathing changed.

"Number thirty-one," she whispered, "is shorter than the others."

"What?"

"There are forty-seven shelves in total," she said. "The normal shelves are all the same height. Only shelf number thirty-one has a lower base than the ones next to it."

"How much lower?"

"One knee."

The main control room was so quiet you could hear the ventilation.

"So that person didn't kneel because he 'couldn't reach it,'" Xu Wangshu said slowly. "He knew that to write this name, he had to kneel."

"Who are you kneeling for?"

"Kneel down and show that name to it," Xu Wangshu said. "After you've knelt, scrape the name off."

She said this very softly.

But everyone heard it clearly.

Qin Lan wrote down the notes, and then looked up.

"Should I add this to the continuation log?"

"Write it," Xu Wangshu said. "Write it exactly as it is, without any explanation."

"What about the message?" Qin Lan asked. "We only know it was written here, but we don't know what it said."

"Yes," Xu Wangshu said.

"Then write: The content is unclear, the writing has been scraped off, but the kneeling posture can be restored."

That's all.

She thought for a moment and then added another line.

[No one can guess what that line of text means. We'll wait for the person to speak.]

Qin Lan closed the notebook, then remembered something else that seemed off.

"There's one more thing," she said. "When we were measuring, we measured the height of forty-six blocks."

"What's wrong?"

"The forty-seventh square, which is Lin Wangchuan's square," she said, "is normal."

What does "normal" mean?

"This means that Lin Wangchuan wrote that message standing up," Qin Lan said. "Only the number thirty-first space was written while kneeling."

No one spoke in the main control room.

One was writing standing up, the other was writing on his knees.

The two lines of text were separated by sixteen spaces, and the postures were different.

"The one I wrote standing up is for myself to see," Lu Chenggong said.

"The one he wrote while kneeling," Xu Wangshu continued, "who was he kneeling for?"

She didn't finish her sentence.

Because once the next sentence is uttered, it will be tantamount to defining the character of the person kneeling.

No one can draw that conclusion.

When Qin Lan put the notes into her notebook, she noticed another detail.

"These two lines of text are separated by sixteen spaces," she said.

"What's wrong with the sixteen squares?"

"Slot number 47 is at the very top of the shelf," Qin Lan said. "Slot number 31 is in the lower middle section."

"One of them was standing at the very top writing," Lu Chenggong said. "The other was kneeling in the middle writing."

"right."

Xu Wangshu wrote this down.

"The shelf has forty-seven compartments," she said. "The two lines of text are about the same thing."

"Which matter?"

"I won't sign," Xu Wangshu said. "One person stands and writes 'I won't sign,' while the other kneels and scratches off their name. Neither of them will sign."

The main control room was quiet for a while.

"Yes," Xu Wangshu said. "What the world is doing now is to make both of these things public."

Lu Chengong looked at this line and suddenly smiled.

"Wait for him to speak." He repeated, "This sentence is currently under 47 squares."

"It's not forty-seven squares," Xu Wangshu said.

"How much is that?"

"One square," she said. "That one square. All the other squares are empty, but this one is still waiting for someone to finish speaking."

The darkness outside the window remained still.

But the temperature at the bottom of the valley didn't drop.