Kaimo Streel returned home when it was completely dark.

After having dinner with his family, he went back to his room and wrote the raw material formula and selection心得 of crystal glass into his book - "The Gate of Alchemy", which recorded his journey from apprentice to chief alchemist, and included all the alchemical formulas summarized by the Chishui City Alchemy Workshop over the years.

Kaimo believed that with this book, he would be remembered in history, and even after thousands of years, those alchemists would deeply remember his name.

It was not until the candle flame approached the base that Kaimo put down his quill and prepared to take off his clothes and sleep.

Suddenly, he remembered that there was a letter from the prince that had not been opened. He glanced at the candle, which was only the length of a fingernail, and decided to use the last bit of time to read the letter, and reply to the messenger orally tomorrow - the small half of the candle was only enough for him to write a few dozen words, but it was enough to finish a worthless letter.

After opening the envelope, there were three sheets of thin paper inside. The first page was the usual polite words, introducing his title and territory. Kaimo was too lazy to read it and skipped directly to the second page.

The content on the second page surprised him slightly. It was neither recruitment nor reprimand, but five strange formulas. If you look closely, each line of the formula consists of three sentences.

"Heh, interesting," he smiled, "Regardless of the prince's purpose, at least he's good at creating mysteries."

He scanned the first line of the formula.

"Saltpeter dry distillation produces nitric acid."

Saltpeter... dry distillation... acid, are all alchemical terms. Wait, Kaimo was suddenly startled, isn't this one of the dual-stone acid production methods in the alchemy workshop?

The acid liquid distilled from saltpeter must be collected in special containers. It looks no different from ordinary water vapor, making it difficult to attract attention. But its corrosiveness is very strong, not only can it corrode the skin, but it can even dissolve some metals.

This... is actually an alchemical formula? Could it be that Border Town also has an alchemist?

He quickly shifted his gaze to the next line—

If the first sentence made him extremely surprised, the second sentence was incredible.

It consists of a pile of inexplicable symbols, which are arranged together to form two equations. Kaimo frowned, he had never seen such strange symbols.

Further down, the third sentence seems to be an explanation of the second sentence, including the names and meanings of those symbols - to be honest, he still couldn't understand it after reading it. The awkward words seem to be newly coined words. He needs to read them repeatedly to associate the words with the symbols. Even so, the meaning of the whole sentence still confused him.

Just then, the candle flame flickered twice and went out.

Damn it! Kaimo cursed inwardly, and without hesitation, he took out a candle from the drawer and relit it.

...

When the second candle had burned halfway, the chief alchemist's hand holding the letter paper was trembling slightly.

The seemingly contentless letter paper took several times longer to read than usual.

The five lines of formulas on the second page of the letter were all alchemical formulas!

If that was all, it would be fine. It is not unimaginable for an outstanding alchemy master to summarize five formulas on his own. However, these five formulas, except for the first acid production method, all echoed each other. Certain newly coined words appear repeatedly, forming a seemingly balanced cycle.

"Nitric acid reacts with silver to produce silver nitrate, water, and nitric oxide."

"Silver nitrate reacts with iron to produce ferrous nitrate and silver."

"Silver nitrate reacts with copper to produce copper nitrate and silver."

"Copper nitrate reacts with iron to produce ferrous nitrate and copper."

He had also done the alchemical reaction of placing a silver rod in acid. Some silver rods were clearly dissolved by the acid and disappeared without a trace - this is the characteristic of acid, corroding everything. But the letter confidently stated that because silver nitrate is soluble in water, it appears to have disappeared on the surface, but in fact, silver only exists in another form, rather than being annihilated.

How is this possible?

No... Kaimo shook his head. Obviously, the other party also expected his thoughts. These formulas echoing each other was not accidental. He realized that the other party was giving him a chance to verify - whether it was silver, iron, or copper, they were all common minerals. If the alchemy is performed according to the following formula, those silver can be replaced again to prove that it has not been annihilated, but still exists in the acid liquid.

Seeing the neatly arranged formulas on the paper, he felt that his breathing became difficult - if these alchemical formulas could all be established, his years of accumulated experience, the efforts of his colleagues, and the "The Gate of Alchemy" he was writing would all be a joke!

"You and the children go to sleep first, I'm going to the alchemy workshop!"

Ignoring his wife's surprised gaze, Kaimo put on his coat and rushed into the night.

When he arrived at the alchemy workshop, he immediately called three disciples on duty and told them that he was going to conduct an alchemical experiment, and asked them to light torches and candles, the more the better. The order was quickly executed. His long table was brightly lit, and the disciples shuttled between the material room, the warehouse, and the refining room, preparing experimental materials for the chief alchemist.

There was still a lot of the acid distilled from saltpeter, and the verification could start directly from the second line of the formula.

He took out some acid and poured it into a glass, then put in a silver rod. As the reaction began, the rod gradually corroded, with bubbles emerging.

While waiting anxiously, Kaimo conveniently unfolded the third page of the letter.

There was only a short sentence on it: "I just did a little bit of work, if you want to know more answers, come to Border Town."

Damn it, this sentence is as good as not writing! If he can really verify what is said in the letter, he will have to meet this unknown alchemy master no matter what. Otherwise, he will have trouble sleeping and eating in the future.

It wasn't until the bubbles stopped emerging that he took out the incomplete silver rod and put a small piece of copper into the glass.

An incredible thing happened. White spots soon appeared on the surface of the copper piece, like the shell of a ladybug. The white spots expanded and covered the entire copper piece, and the acid in the glass also turned from colorless to blue.

Exactly the same as described in the letter!

"The white precipitate is silver, and the newly generated substance, copper nitrate, is as soluble in water as silver nitrate, but its solution is blue."

Kaimo Streel stared at the result in the cup, standing there in a daze.

...

The next morning, when Chames came to the alchemy workshop, he was taken aback by the chief alchemist, who had dark circles under his eyes and looked haggard.

"Didn't you sleep all night yesterday?" He was surprised. "For the second batch of crystal glass?"

Kaimo shook his head, pulled Chames to the long table, and asked tiredly, "You were my most proud disciple. I want to ask, what do you think of alchemy?"

"Uh... just like what you taught me," he noticed that there were some glasses on the table, several of which contained solutions of different colors, one of which was sky blue and very eye-catching. Is this why the chief master didn't sleep all night last night? Although Chames was full of confusion, he honestly replied, "I also feel the same way. The essence of alchemy is to find the truth of the world in disorder and chaos..."

"No, no, Chames, I was wrong," Kaimo interrupted, "Everyone was wrong, alchemy is not like this."

Not like this...? Chames felt that the other party was really strange. First, he did alchemy all night, and now he asked some inexplicable questions, but before he could ask further, the chief master had already said to himself: "Alchemy is more orderly than you and I imagined, it can even be said to be rigid - like one plus one equals two, no matter how it changes, matter will not increase or disappear."

"Will not increase or disappear? What are you talking about? Screening and combining some common raw materials to create incredible new things, isn't this what alchemists often do!" He asked puzzled.

"Yes, I used to think so too, until the lord of Border Town wrote me a letter..." Kaimo Streel patted him on the shoulder, and the words he said made Chames's heart tremble, "I will leave here soon and go to Border Town to find answers. You... are you willing to go with me?"