A quarter of an hour later, two yamen runners brought in the items and arranged them in the hall.
The three officials glanced at the apparatus and then turned to look at Xu Qi An.
Prefect Chen said gravely, “Everything you requested is here. You must provide this official with a satisfactory answer.”
His attitude had shifted.
During the quarter-hour, this fourth-rank official had racked his brains, forced to admit that Xu Qi An’s deductions were quite reasonable. However, many mysteries remained unsolved, such as the fact that the tax silver had indeed fallen into the river.
What was the secret behind it all? He couldn’t fathom it.
“If this humble one helps Your Honor solve this case, could you petition His Majesty to absolve my Xu family of guilt?”
Great Feng placed great importance on father-son inheritance; a son could bear his father’s guilt or make amends for his father’s crimes.
“Naturally,” Prefect Chen nodded.
Xu Qi An nodded and squatted before the apparatus. The items before him were candles, salt, a porcelain cup, and iron wire.
What he needed to do was simple: extract sodium metal, using high school chemistry knowledge.
In ancient times, this would have been impossible to extract, with two main obstacles: electricity and the melting point of sodium chloride.
But in this world, Xu Qi An knew there was one profession that could accomplish this.
Court of Astronomical Affairs’ sixth-rank Technician: Alchemist!
Alchemists were a well-known profession in Great Feng, their various inventions and creations having long been integrated into ordinary people’s lives.
Xu Qi An wasn’t certain that the exploding tax silver was sodium metal, but that wasn’t important. What mattered was opening up a line of thought to explain the phenomenon of the exploding silver.
In the process of solving cases, bold hypotheses and rigorous reasoning were essential preliminary work. Only then would one verify and gather evidence.
In his previous life, he had encountered a memorable murder case where detectives had brainstormed day and night, making several hypotheses about the case process based on clues, using these as a foundation to gather evidence.
Then they had completely overturned everything and reasoned anew.
The tax silver might not be sodium metal, but in any case, an alchemist could accomplish this.
That was enough.
Finding the correct direction for the officials was what he needed to do.
Once the direction was right, they could follow the clues step by step to investigate, making it not difficult to find the mastermind behind it all.
If they remained stuck in the mindset of supernatural mischief, the case would never be solved. Even if the case were solved in the future, he would already be far away from the imperial court.
He dissolved coarse salt in water, stirred it, then covered the cup’s mouth with paper and slowly poured the salt water through.
After filtering, he placed the porcelain cup over a candle to heat it, constantly stirring with a bamboo stick.
Soon, the saltwater in the cup dried up, leaving behind crystals of sodium chloride.
Essentially, this was further purifying the salt.
Prefect Chen, the middle-aged man, and the stunningly beautiful young woman in the yellow dress stood watching intently from the side.
Xu Qi An looked up and grinned at the young woman in the yellow dress: “You’re a disciple of the Court of Astronomical Affairs, aren’t you, My Lady?”
He had noticed the feng shui compass at her waist, something only disciples of the Court of Astronomical Affairs would use.
The young woman in the yellow dress made an affirmative sound, smiling brightly: “My master is the Chief Astronomer of the Court.”
Her exquisite, radiant oval face was like a peeled egg, fair and flawless.
The Chief Astronomer’s disciple… never mind about the chest… Xu Qi An said in a gentle tone, “Would you please melt these crystals for me, Elder Sister?”
The melting point of sodium chloride is about 800 degrees Celsius.
The young woman in the yellow dress pouted slightly: “Fire control is an ability only alchemists have. I’m just a feng shui master.”
“But my master gave me a magical tool,” she changed tack, taking the feng shui compass from her waist. Her jade-like fingers manipulated it a few times, inputting qi, and the character for “fire” lit up.
“Step back!”
Xu Qi An immediately retreated. The next moment, a blindingly bright tongue of flame erupted, engulfing the porcelain cup.
“Stop!” Xu Qi An called out immediately, then quickly inserted two iron wires into the porcelain cup and asked, “Electrify… no, thunder magic! Be careful to control the voltage… um, this step is very difficult, it might fail many times.”
She rotated the feng shui compass, her delicate fingers lighting up the character for “thunder.” Several arcs of electricity flashed in the void, touching the iron wires.
“Sizzle…” The molten sodium chloride underwent a violent chemical reaction.
“Stop!”
Xu Qi An held his breath and leaned in to look at the cup’s mouth. A lump of silvery metal had formed, with edges of partially transformed crystals and impurities.
It succeeded on the first try, the voltage was just right… Xu Qi An was delighted.
The electrolysis method for producing sodium metal requires a voltage of about 6-15 volts. He had been mentally prepared for repeated failures.
Unexpectedly, luck was on his side, and it worked on the first attempt.
Prefect Chen and the middle-aged man eagerly leaned in to look. In the cup was a lump of silver-colored metal that, at first glance, looked remarkably similar to silver.
Prefect Chen’s pupils constricted, his heart extremely shocked.
Li Yuchun clenched his fists tightly, staring blankly at the silver metal lump. It was as if lightning had struck in his mind, clearing away all the fog.
“Please look, honored officials,” Xu Qi An poured out the sodium metal, wrapped it in paper, and weighed it in his hand. “This substance is much, much lighter than silver, but its appearance is extremely similar. If someone were to use this to impersonate silver, could it not pass for the real thing? The honored officials can weigh it yourselves.”
He handed the sodium metal to Prefect Chen. By now, the metal’s luster had gradually dulled, becoming almost identical to silver.
The middle-aged man took it and weighed it in his hand. His eyes shining brightly, he said repeatedly, “Indeed, it’s much lighter. If what was being transported was this, then it all makes sense. Miss Caiwei, you try it.”
The young woman in the yellow dress took it, weighed it, and then looked at Xu Qi An with a strange expression: “You… are you an alchemist?”
No, I’m not. I’m just a conveyor of chemistry knowledge.
Scholars tend to have more active minds. After his initial delight, Prefect Chen suddenly shook his head and said gravely, “No, it’s not right. Even if the silver was replaced with this, what about the explosion? If there weren’t supernatural creatures hiding in the river, how could fake silver explode upon entering the water?”
Xu Qi An didn’t answer. He took the sodium metal, walked to the desk, and dropped it into the brush-washing bowl.
An intense light flared up, accompanied by billowing smoke.
“Boom!”
The sodium metal reacted violently with the water, causing fine cracks to appear in the brush-washing bowl.
“This… this…” Prefect Chen was stunned.
“This fake silver explodes when it meets water, which explains why there was such an explosion when the silver fell into the water,” Xu Qi An explained.
The middle-aged man muttered, “From the very beginning, we were misled. The mastermind behind this used the explosion and the strange wind to make us think it was the work of supernatural creatures, focusing our investigation on tracking and searching for them.
“No wonder the Court of Astronomical Affairs’ qi-observing technique couldn’t detect any supernatural creatures.”
Xu Qi An added, “After the tax silver fell into the water, the soldiers only recovered a little over a thousand taels of silver. If I’m not mistaken, these silver pieces were probably placed on top to deceive people.”
Everything fit together perfectly, all the anomalies now made sense.
“Xu Qi An!” The middle-aged man’s eyes were full of approval. “Good, very good.”
His brow suddenly furrowed, fixating on Xu Qi An’s crooked collar. Li Yuchun, continuing the motion of patting his shoulder, helped straighten Xu Qi An’s collar.
Xu Qi An was overwhelmed by the honor, that this official would show such appreciation for him.
Prefect Chen frowned and said, “If the silver was fake, where did the real silver go?”
Hearing this, the young woman in the yellow dress also showed a grave expression: “The tax silver passed through many hands from leaving the treasury to entering the capital. If we were to assign blame, a large number of officials would have to be imprisoned. The difficulty of recovering the silver would be like searching for a needle in the sea. Moreover, this matter has already exceeded our authority; we must report to His Majesty.”
Prefect Chen nodded; this was what he meant.
The middle-aged man had a different view. In a low voice, he said, “The tax silver was escorted into the capital, passing through many hands. If it were fake, it would have been discovered long ago. The only possibility is that it was switched recently.”
Prefect Chen’s eyes lit up; this greatly narrowed the scope of the investigation.
“Someone prepare a sedan chair, quickly! This official needs to go out,” Prefect Chen hurriedly rushed out of the inner hall.
The middle-aged man followed closely behind.
Xu Qi An hastily called out, “Prefect, please don’t forget your promise to this humble one.”