It wasn't an apple that hit Newton.

He then straightened his back and smiled, ready to receive Lavoisier's surprise.

result.....

Lavoisier stared at the red-haired man who had inexplicably knocked on his door, looking quite pleased with himself, and looked bewildered.

After a two-second silence, she slowly spoke, "...Who are you?"

???

Are you kidding me? I think I left a pretty deep impression, right?

Li Cheng's lips twitched. He subconsciously thought it was a joke, so he asked again, "You really don't remember me?"

Seeing the other party's confident attitude, Lavoisier instinctively began to doubt his own memory—after all, this wasn't the first time.

"I'm sorry, let me think about it."

Lavoisier frowned his handsome brows again, pondered for a moment, and then revealed a knowing expression.

Li Cheng nodded in satisfaction upon seeing this.

Unexpectedly, Lavoisier adopted a confident demeanor and said, "You're the one who came to consult about legal issues last week, aren't you? I do remember that signature red hair."

???

So it's only been half a month and you've already forgotten me... After a brief moment of confusion, Li Cheng forced a smile: "Let me reintroduce you, Albert Lee. We met at the library."

Lavoisier tilted his head, puzzled, and asked, "Albert Lee...?"

Trying to be cute won't work! You're so goldfish-brained!

Li Cheng could no longer maintain his so-called composure. His dead fish eyes, etched with the strain of a goldfish, stared blankly as he spoke, word by word, in a flat, monotone tone: "Burning is a reaction. And this reaction requires a medium called oxygen..."

"Oh oh oh!"

As if he had received some kind of secret code, Lavoisier suddenly realized that the Li Cheng in front of him was the man he had met in the library who claimed to be able to solve his problem.

She said in a tone that was both surprised and excited, "It's you?!"

Li Cheng squinted: "Yes, it's me."

Although he was initially surprised, he now doesn't know why, but he feels no sense of accomplishment whatsoever.

"Sorry, I thought you were just joking."

Lavoisier apologized, then continued, still agitated: "So you came here because you remembered the name of that book?"

Finally, when they got down to business, Li Cheng's attitude became a bit more serious. His eyes went from dead fish to salty fish, his back straightened up again, and he even straightened the corner of his clothes that he had messed up earlier.

"Yes, I remember everything now..."

Li Cheng nodded, then revealed the name he had thought of beforehand: "The book is called 'An Introduction to the Fundamentals of Chemistry'."

"Introduction to Basic Chemistry...?"

Lavoisier began to have doubts again: "It sounds very ordinary. Is it really this book? I feel like there are many books with the same title, right?"

"Don't worry, this is the book. And you don't need to look for it. I wrote the contents down on a piece of paper and brought it with me. You'll know if it's real or fake after you've read it."

As Li Cheng spoke, he waved the wad of manuscript paper he had packed up in his hand, and said with a half-smile, "Want to see it?"

Lavoisier looked eager and nodded repeatedly: "Yes."

"It feels like I'm abducting a little girl..." This strange thought popped into Li Cheng's head, but he immediately dismissed it—just kidding, where can you find a twenty-year-old girl these days who's still so confident and brimming with confidence? Does she think this is some kind of ***?

"Hehe, although I can show it to you."

Li Cheng looked around at the messy street and smiled, "But the entrance isn't convenient. How about we go inside and talk slowly?"

"of course can."

Lavoisier readily opened the door and quickly stepped aside, revealing glimpses of the dilapidated wooden floorboards.

Seeing that the other party seemed to be planning to let an adult man into the house without any precautions, Li Cheng secretly began to worry about the other party's personal safety. What if he accidentally let someone with ill intentions into the house... Oh, that's me. Well, it's alright then.

Li Cheng shook his head, shaking off his chaotic thoughts, and stepped into the simple wooden house.

Chapter Forty-Four: Travelers and Fellow Villagers

Lavoisier's home was sparsely furnished. Apart from a neat stack of books and pens, the only furniture consisted of a few wooden tables, chairs, and beds in natural wood tones... and then? That was it.

This is too tragic... Li Cheng couldn't bear to watch.

"I'm sorry, I don't have anything to offer you. Please have some cold water."

Lavoisier showed no awareness of poverty whatsoever. As the hostess, she merely brought over a glass of cold water and then calmly sat down in the seat opposite Li Cheng.

Then she got straight to the point: "Your statement that 'air is also a substance, a very complex substance, and combustion requires a substance in the air' was of great help to my research."

"Isn't your memory pretty good? It seems you only remember what you want to remember..." Li Cheng nodded: "May I listen?"

"can."

Lavoisier continued, "From then on, I began to think about how to extract substances from the air—you can extract pure water by heating it, but I couldn't think of a way to purify substances from the air."

"Perhaps I should heat some substance, but I really don't know which one to use, so I can only try them blindly one by one."

We're already on the right track, all we're missing is a bit of luck... Li Cheng comforted us, "It's okay, we'll find it soon."

"I think so too, but perhaps there are some ways..."

Lavoisier hesitated to speak, but his gaze remained fixed on the package in Li Cheng's hand.

Good heavens, you think you can trade my book for a cup of water... Li Cheng was a little speechless.

However, that's exactly what he came here to do. It would be a real headache if Lavoisier had no interest in it at all... Besides, there's no point in saying anything to this research fanatic; you can only try to please him.

Under Lavoisier's expectant gaze, Li Cheng handed over the blue package in his hand: "Let me make this clear first, this isn't free."

Lavoisier gave a perfunctory "hmm" and eagerly unwrapped the package with both hands, hoping to find the answer she had been searching for.

Inside the package was a neat stack of manuscript paper strung together with thin string, resembling the beginnings of a book.

The first page was the title, which Lavoisier stared at intently.

"Introduction to Basic Chemistry"

It's such an ordinary name, she thought, as she turned to the next page.

The second page contains only one sentence.

Matter cannot disappear or be created; it can only be transformed from one type of matter into another—the law of conservation of matter.

This simple sentence immediately made Lavoisier frown and fall into thought.

Li Cheng sat opposite the light-colored wooden desk, his mind wandering.

The law of conservation of matter is one of the fundamental laws of nature. In any material system isolated from its surroundings (isolated system), regardless of the changes or processes that occur, its total mass remains constant.

This law has been generally accepted since the 18th century when the French chemist Lavoisier (♂) experimentally overturned the phlogiston theory.

However, Lavoisier now appears in the 17th century... Li Cheng looked at Lavoisier (♀) in front of him and admired her elegant posture even when she was reading a book.

Poverty could not diminish her beauty in the slightest; her long silver hair shone like stars in the sky, her face was thin yet gentle, and her features combined the three-dimensionality of Westerners with the delicacy of Easterners.

Looking down, her tall figure could not be concealed even by her loose, brown clothing, which was mainly due to the good nutritional support provided by her lawyer parents during her childhood—and of course, Lavoisier's own efforts cannot be overlooked.

Lavoisier was oblivious to Li Cheng's somewhat lewd gaze; she was focused on her book, *An Introduction to the Fundamentals of Chemistry*.

Initially, when she saw the word "foundation," she was somewhat dismissive. As a graduate with two degrees from the University of Paris, Lavoisier felt that the word "foundation" was somewhat distant from her.

But after reading it carefully, Lavoisier realized that this 'foundation' was not the kind of 'basic knowledge' she had thought it to be. It referred to the 'foundation' of the entire chemical world, containing all the 'basic architecture' hidden at the very bottom of the chemical world, serving as its deepest secrets.

The mere statement, "Matter cannot be created or destroyed, but can only be transformed from one substance into another," sent chills down Lavoisier's spine.

This is what she has always held onto, just like finding a kindred spirit!

Continue flipping through.

Section 1: Atoms.

There are many invisible particles in nature. These particles make up matter, and matter interacts with each other in various ways and is constantly changing. I call them atoms.

This section directly answers many of Lavoisier's questions, and at the very end, it even proposes a method for producing oxygen.

Wait, how do we produce oxygen?

Lavoisier's eyes lit up; finally, finally, the problem that had troubled her for so long was about to be solved.

This is truly a wonderful book!

Lavoisier exclaimed in admiration, then realized she had reached the end of the page and eagerly turned to the next.

However... it's gone.

The next page was blank, without a single word.

The seemingly thick stack of manuscript paper turned into a completely blank page when only a small portion was flipped through—a blank page without a single word.

Lavoisier: ? ? ?

Is this how you write a book? Aren't you afraid your editor will come knocking on your door with a kitchen knife?

What's next?

So how exactly is oxygen extracted?

So what exactly is the method for producing oxygen?

"What's next?"

Lavoisier was very excited. She jumped up from her seat with a bang, knocking the chair to the ground with a loud 'bang,' which even startled the somewhat guilty Li Cheng.

"What's next?"

Lavoisier repeated herself, her red eyes growing even more bloodshot and strikingly bright.

"You really want to see my lower half? That's not a good idea..." Li Cheng coughed twice: "I remember I said this isn't free, right? To prevent you from reneging on your promise after you've read it, I've only written a part of it first."

If the conservation of matter is a law of nature, then equivalent exchange is a law of human society—in most cases.

Lavoisier slowly calmed down from her initial agitation and glanced around the room: the dilapidated wooden cabin, the long-neglected floors, the furniture left behind by the previous owner...

She had nothing, no savings, and her earnings as a defense lawyer were almost always spent as soon as she received them.

Compared to his shrewdness in his field of expertise, the mess of life caused Lavoisier a great deal of trouble, often leading him into embarrassing situations.

She sighed helplessly and said somewhat awkwardly, "As you can see, I have nothing."