Chapter 35: Seven Days!

"Really!?"

Before Du Gou could speak, Cheng Chumo's booming voice rang out right beside him.

"Master Liu, do you really know when the remains of the Prince of Xi were stolen?"

Cheng Chumo’s volume was such that someone three miles away could have heard him. In an instant, everyone’s gaze shifted and fell squarely upon Liu Shuyi.

Liu Shuyi shot a glance at Cheng Chumo and said, "Speak any louder, and you might as well let the thieves hear you too."

Upon hearing this, Cheng Chumo’s dark face flushed red for a rare moment. He sheepishly shrunk his neck and said, "I was just too excited." He lowered his voice, but couldn't help asking, "What exactly is going on? How did you suddenly figure out when the thieves struck?"

Du Gou and Zhao Feng were also looking at Liu Shuyi, filled with confusion.

Liu Shuyi did not hide anything and stated directly, "The coffin nails told me."

"Coffin nails?" The group was stunned.

Wang Kun, who had been specifically tasked with inspecting the coffin nails for Liu Shuyi, looked even more bewildered. "What did they tell you? How come I don't know anything about it?"

Liu Shuyi smiled and said, "They told me two things."

"The first thing, once again, was helped along by Vice Minister Wang."

Wang Kun frowned. "You mean... you are talking about the sinking of these coffin nails?"

Liu Shuyi nodded. He looked at Du Gou and the others and explained, "Just now, Vice Minister Wang helped me inspect the coffin nails. Based on his expert judgment, it is certain that these nails were secretly pulled out. However, the person who pulled them out returned them to their original positions with such care that we, as laymen, did not notice the slightest abnormality."

Du Gou had been away just moments ago and was completely unaware of this. Hearing this now, he immediately grasped Liu Shuyi’s meaning. "In other words, the thieves opened the coffin lid by pulling out the nails to steal the remains of the Prince of Xi?"

Cheng Chumo frowned. "But back in the tomb chamber, didn't Master Liu say the coffin lid was intact and that the thieves couldn't have stolen the remains? Now you're saying they opened the lid to steal them—doesn't this contradict your earlier conclusion?"

"It is different." Liu Shuyi was pleased that Cheng Chumo had spotted the contradiction, though it was a pity that Cheng’s reasoning was not particularly flexible.

He explained, "While the lid was indeed opened in both scenarios, opening it inside the tomb chamber versus somewhere else carries entirely different implications."

"If the thieves had opened the coffin lid inside the tomb, they would have had no reason to spend time and energy carefully hammering the nails back in. Look at the nails—at the point where the nail head meets the lid, aside from the head being slightly sunken, there are no marks of impact around the surrounding wood. This requires not only high-level skill but also enough care and time to hammer them in meticulously."

"At the time, the tomb was collapsing, and the mausoleum guards were expected to arrive at any moment. After stealing the remains, the thieves had to flee immediately to avoid capture by the imperial court. Why would they waste time doing something that offered them no benefit?"

"That is why, while in the tomb, I said the lid had not been opened and the thieves could not have stolen the body through the small side cracks, concluding that the body was not lost in the tomb."

Cheng Chumo scratched his head, thought for a while, and then nodded in realization. "So that's how it is."

"But it is different elsewhere!" Liu Shuyi smiled and continued, "We have already determined that the remains were stolen before they reached the tomb chamber. To hide the secret of their theft, the thieves had to ensure no one would notice. That is why they carefully replaced the nails after taking the body."

Cheng Chumo finally understood completely. "These thieves are truly cunning, restoring even the nails perfectly. Who would have thought these nails, which look perfectly fine, had been tampered with?"

Liu Shuyi nodded. "Indeed, the thieves were cautious and highly skilled; ordinary people would find it difficult to notice. Fortunately..." He looked at Wang Kun and smiled. "We have Vice Minister Wang’s help. His expertise is many times greater than that of the thieves. They might have hidden it from our eyes, but they could not hide it from a veteran like Vice Minister Wang with decades of experience."

Flattered by Liu Shuyi, Wang Kun actually felt a bit embarrassed. The burly man rubbed his hands and said, "I'm not as formidable as you say."

Liu Shuyi smiled slightly. "Vice Minister Wang just told me that while modesty is a virtue, excessive modesty is hypocrisy..."

Wang Kun’s expression stiffened. He hadn't expected the words he had just spoken to Liu Shuyi to be thrown right back at him. Helpless, he could only accept the compliment, just as Liu Shuyi had done.

Du Gou ignored their exchange and, reflecting on Liu Shuyi’s words, asked, "But this only proves how the thieves stole the body; it doesn't prove where they did it, does it?"

"Correct," Liu Shuyi nodded. "If that were all, it would be of limited help. But luckily, the coffin nails told me a second thing."

Wang Kun suddenly remembered the question Liu Shuyi had asked him earlier, which he hadn't been able to answer.

"You mean..." He looked at Liu Shuyi. "Are you talking about what you asked me regarding when the nails were pulled out?"

"When the nails were pulled out?" Cheng Chumo was startled. "Can that even be determined?"

"No!" Wang Kun shook his head directly. "But..." his tone shifted, "...Master Liu says he can."

"What? Master Liu can determine that?" Hearing this, Du Gou and the others looked at Liu Shuyi with surprise.

Liu Shuyi didn't keep them in suspense. "I cannot determine the exact time, but I can estimate a rough window."

"This... how can you estimate it?" Wang Kun stared intently at Liu Shuyi. Even he, a master craftsman, couldn't be certain; he didn't know what method Liu Shuyi could possibly use.

Liu Shuyi looked at the slightly sunken nail on the black coffin lid. "Does Vice Minister Wang know about the oxidation and rusting of copper nails?"

"Ah?" Wang Kun was puzzled. "I understand rust, but what is oxidation?"

Liu Shuyi said, "Oxidation can be considered the step that occurs before rusting. Generally, when a copper nail is exposed to air, it will first oxidize and darken, and then develop green copper rust. Look at these nail heads. They have been exposed, and reasonably speaking, more than a year has passed since the burial in the ninth year of Wude. Even if they didn't rust, they should be heavily oxidized."

"However, the surface of these nail heads remains bright, with almost no obvious signs of darkening..." He looked at the expert Wang Kun. "Vice Minister Wang, do you think this is normal?"

"This..." Wang Kun’s eyes flickered. "Of course it's not normal! The Prince of Xi died suddenly in the ninth year of Wude, and the court had no time to prepare a proper tomb, so it was a temporary burial. Everything was suboptimal; under such conditions, after a year, the copper nails should have rusted long ago!"

"Right! Why didn't I think of that!" He became more and more excited, pacing back and forth around the coffin. Suddenly, he clapped his hands. "I know now!"

He looked at Liu Shuyi. "It’s the thieves! When they pulled out the copper nails and hammered them back in, they knocked off the rust on the surface! And each hammering acted like polishing, which is why the nail heads are so smooth and bright!"

Liu Shuyi nodded, smiling. "And now, the nail heads are still very bright... Vice Minister Wang, how long ago do you think they were hammered? Or, in other words, how long would it take for them to show signs of darkening?"

"This..." Thoughts raced through Wang Kun’s eyes. He walked back and forth again, muttering to himself. To Cheng Chumo, it sounded like a monk chanting sutras.

Suddenly, he stopped. He turned sharply to look at Liu Shuyi. "Very short! The time is very short!"

"The Prince of Xi’s coffin was kept in the tomb for a month. After the tomb collapsed, the coffin was exposed to the ice and snow outside. Although the cold slows the rusting and darkening of copper, it cannot withstand direct contact with damp ice and snow."

"Yet, even under these conditions, it hasn't darkened. It only means it was in pristine condition when it was moved to the tomb!"

"If it had remained in the previous temporary tomb, unable to be isolated from the air, it wouldn't have lasted long before darkening and rusting!"

Listening to Wang Kun, Liu Shuyi said, "So, may I understand it this way... the time the nails were hammered is very close to the present, at most a month or two since it was moved from the temporary tomb?"

Wang Kun frowned and thought. "Even a month or two feels long, but I dare not say for sure. After all, the darkening and rusting of copper depend on many factors. I can only estimate a rough range."

"That is enough!" Liu Shuyi said.

"Enough?" Cheng Chumo couldn't help but ask. "Isn't that still a long time? After the coffin was moved from the previous tomb, it was kept at the Taichang Temple for seven days for high monks to chant prayers, and only then moved to the current mausoleum. That’s two months plus seven days—over sixty days!"

Zhao Feng also nodded repeatedly. While shortening the window to sixty days was impressive, they had limited time, and sixty days was still too long to investigate.

Liu Shuyi, however, said, "I never said the range was sixty days."

"What? Not sixty days? Then..."

"The seven days it was at the Taichang Temple!"

"The seven days at the Taichang Temple!?" Cheng Chumo almost screamed again. He stared at Liu Shuyi, wide-eyed. "How is that possible? When the coffin was at the Taichang Temple, there were guards day and night, and high monks chanting almost every day... People were coming and going constantly for those seven days. How could the thieves have acted then?"

Du Gou also frowned, his eyes filled with disbelief.

Liu Shuyi said, "I don't yet know exactly how they did it, but I am certain it happened during those seven days! As for the reason..." He stepped forward to the front right of the coffin and squatted down.

"Come and look." He pointed to the spot where the nail head met the coffin lid. "What do you see?"

Du Gou and the others leaned in, observing carefully.

"What’s wrong with this?" Cheng Chumo blinked. "Isn't it just that the nail head has sunk into the lid? You already mentioned that."

"It seems to have something on it..." Zhao Feng said suddenly. "Look at the edge of the nail head; there seems to be a bit of blue matter. It’s not very obvious, so I don't know if I’m seeing things."

"Blue stuff?" Cheng Chumo leaned in closer. "Hey? There really is a little bit." He checked the other nails. "Only this one has it. What is this?"

Wang Kun observed it carefully, stroking his chin. "Master Liu, what kind of eyes do you have? I checked every nail just now and didn't notice a thing."

Liu Shuyi smiled. "I am an official of the Ministry of Justice, so I pay more attention to details. It is normal that Vice Minister Wang did not notice."

"Is that so..." Wang Kun nodded.

Du Gou, however, looked at Liu Shuyi deeply. Why would that be the reason? He was also a Ministry of Justice official and had met many others, but none of them—including himself—could observe things as meticulously as Liu Shuyi.

He knew the principles of earth movement, and the craft of copper rust... He suddenly felt that Liu Shuyi was like a mysterious, bottomless pit; whenever needed, he seemed to be able to produce knowledge that no one else possessed.

He took a deep breath. "What is this? What does it signify?"

"What is it?" Liu Shuyi looked at Du Gou and smiled. "Vice Minister Du should know, as we just dealt with it in our last case."

The last case... blue... Suddenly, Du Gou understood. He widened his eyes. "Incense ash!?"

"Incense ash?" Cheng Chumo was stunned. He reached out and wiped it, saying, "It's very fine, almost like it's not there. It really does seem like incense ash."

"But what could incense ash signify?"

Liu Shuyi said, "Don't be impatient..." He looked at Wang Kun. "Vice Minister Wang, can you pull this nail out?"

Wang Kun didn't know what Liu Shuyi was up to, but his curiosity was piqued. "Alright!" He picked up his tools and, with almost no effort, easily pulled the nail out.

"Here!" Wang Kun handed it to Liu Shuyi.

But Liu Shuyi shook his head. "The important thing isn't the nail, but the part of the lid that was pressed by the nail head."

He leaned in close, and when he saw the slight blue trace on the clearly depressed area, he laughed softly. "Just as I expected."

Cheng Chumo still didn't understand. "Isn't this the same as the ash being on the head of the nail? What’s the difference? Why did you have to pull it out to see?"

"It is different," Liu Shuyi shook his head. "If there is ash on the nail head, it could have fallen there after the nail was driven in..."

"But for there to be ash *under* the nail head, it can only mean one thing..." He scanned the group and said slowly, "That is... the ash fell there *before* the nail was driven in!"

"Before the nail was driven in..." Du Gou’s pupils contracted. "I see! No wonder you said it happened during those seven days at the Taichang Temple!"

Cheng Chumo scratched his head. "Vice Minister Du, could you please explain clearly!"

Liu Shuyi smiled. "General Cheng, think about it: under what circumstances would incense ash get trapped under the coffin nail? Or rather, under what circumstances would incense ash drift onto the coffin lid?"

Cheng Chumo frowned and began to think.

Liu Shuyi guided him. "Look at the nail Vice Minister Wang just pulled out. There is some rust on the underside of the nail head, which shows that the nail has been rusting over the past year."

"And the ash is *on top* of the rust, not *within* it. This shows the ash certainly did not fall there when the Prince of Xi was first buried."

"Therefore, the only time it could have fallen on the coffin lid was when the thieves pulled the nail out and hammered it back in."

"If the thieves had pulled the nail out in the previous tomb, the ash could not have appeared. The tomb was sealed, and rituals could only be conducted outside; no one was allowed to enter. In that situation, neither incense ash nor paper ash could have appeared in the tomb!"

"But those seven days at the Taichang Temple were different!" He looked at Cheng Chumo. "Before the reburial, the Prince of Xi’s coffin had to be kept at the Taichang Temple for seven days for the high monks to chant prayers. During those seven days, the incense could not be extinguished. A simple gust of wind could blow the ash onto the coffin lid behind the incense burner!"

"So, after excluding the tomb—which we have already proven with evidence to be impossible—even if you say the Taichang Temple had people coming and going, even if you say it sounds impossible..."

He swept his gaze over everyone, and under their subconsciously tense stares, he slowly said, "It... is still the truth!"