Transmigrated into a female county magistrate during a famine, leading her country to prosperity

"How are your old eyes?"

Liang Fu was eagerly waiting for Shen Zheng to tell him what the real treasure was when Shen Zheng suddenly asked him this question.

"Eyes?" Liang Fu was a little confused, but still answered: "When I was young, I had very good eyesight. I could see things that others couldn't see clearly, and I was envied by many people for this."

When a person is young, he will also be old.

Liang Fu's words were full of sighs, and Shen Zheng already knew the answer: "As you get older, the closer and more subtle things are, the harder you can see, right?"

The lens of the eye gradually loses its accommodative function, presbyopia... seems to be a physiological change that is bound to occur in human life.

"Yes... maybe everyone will eventually grow old." Liang Fu has been trying to convince himself to accept this inevitable outcome, but he is still a little unwilling, "But I am afraid."

He looked at the scattered papers on the table and said with a wry smile: "There are still so many unknown things waiting for us to explore, I can hardly see clearly..."

He understood that the inheritance of civilization is the continuation of life, but he really disliked the phrase "the will is there, but the strength is not enough".

Shen Zheng could understand the helplessness and helplessness hidden in Liang Fu's words.

This feeling...is like when she is nearsighted but doesn't have glasses, but the teacher happens to arrange her to sit in the last row.

The confusion of not knowing what the teacher is writing, the fear of being called on by the teacher to answer questions, and the helplessness of not being able to do the exercises after class are simply suffocating.

She smiled at Liang Fu, her heart filled with joy at being able to help him: "When I make the colored glaze, you will be able to see clearly."

"What?!" Liang Fu raised his head, his eyes full of shock.

In an instant, many possibilities flashed through his mind.

——Can glass be used as medicine to treat eyes?

——Could it be that colored glass has extraordinary benefits for the eyes, just like a jade pillow, which can calm the mind when used every night?

He couldn't help but ask, and got a negative answer from Shen Zheng.

"No......?" Liang Fu was puzzled, "Then why?"

Shen Zheng made the same gesture she had shown to Yu Shizhang, and said, "Colored glaze can be made into something called 'glasses'. No matter if the wearer is short-sighted or farsighted, as long as they look through the 'glasses', they can see things clearly."

This action was actually a bit funny, but Liang Fu didn't find it funny at all. Shen Zheng's words and actions only brought him shock.

He knew very well in his heart that if Shen Zheng hadn't told him, he might never have figured out in his lifetime whether a broken eye could still see again with the help of external objects.

"But..." Liang Fu knew Shen Zheng would not lie to him, but the curiosity in his heart came up again: "But why? Eyes are inside the body, unlike our hands and feet, which can be fixed with external objects if broken."

"Hmm..." This question was actually a bit difficult for Shen Zheng. It was not that she did not understand the principle of how glasses improve vision, but she did not know how to explain the eye axis and lens to Liang Fu.

After thinking for a long time, Shen Zheng finally came up with a slightly more appropriate metaphor.

"You know that when light shines on certain gemstones, they shine brightly, don't you?"

Liang Fu nodded seriously.

During the years he spent in Beijing, he was often dazzled by the jeweled hairpins and earrings of the noble ladies.

"We may call this phenomenon 'refraction of light'." Shen Zheng stood up and opened the window, then dipped his finger in the tea and put it on the table.

The sunlight shines through the window and onto the table, making the tiny drops of water look particularly dazzling.

"Refraction of light?" Liang Fu murmured.

That drop of tea, which is ordinary on ordinary days, seems a little special today.

"It's the refraction of light." Shen Zheng stretched out her hand to block the light on the tea, and the tea also became dim.

She said: "The light was originally in the air, but when it shone into the water droplets, its direction changed and it was deflected. This is called the refraction of light."

Shen Zheng's words were actually said sparingly.

In fact, the propagation speed of light in different media is different, so the propagation speed affects the direction of light. If she said this, Liang Fu might ask again - "Does light have speed?"

"I understand now." Liang Fu nodded and sighed, "So this phenomenon is called the refraction of light."

He smiled and looked at Shen Zheng. "When you put chopsticks into water, they look like they are broken. This should also be the 'refraction' of light, right?"

The words were a question, but his tone was firm.

"Your Excellency is very wise." Shen Zheng admired Liang Fu's ability to "draw inferences from one example to another."

Then, she pointed to her eyes and said, "The reason why we are short-sighted or long-sighted is because the shape of our eyeballs has changed, causing problems with the way our eyes 'refract' what we see."

To put it simply, the reason for vision loss is actually the elongation of the eye axis, or the "refractive error" of the various media in the eye, which causes "distortion" of the image.

Liang Fu touched his eyes and exclaimed, "It's actually like this... But, the shape of my eyeballs has changed a little, but I didn't feel anything at all."

When you think about it carefully, it’s actually quite scary!

Shen Zheng laughed when she heard this: "If it weren't for the damage to our eyesight, it would be difficult for us to perceive the subtle changes inside our eyeballs. What we need to do is to polish the colored glass into an object that can match our eyes to 'refract' light. In this way, the deflected 'refraction' can be bent back."

If these words had not come from Shen Zheng's mouth, Liang Fu would have thought it was a fantasy.

But the person in front of him was Shen Zheng, and he didn't even have the thought of "questioning".

His hand still lingered on his eyelids, and he murmured, "Amazing, amazing, it's really amazing! Lord Shen, this thing is simply exquisite, if it can be published..."

If it can be released...

Liang Fu felt excited.

Not to mention himself, let's just talk about his Ministry of Works. Over the years, two old men have gradually retired from the court due to blurred vision.

One of them was a few years younger than him, but he was like a mentor to him - the level of a person's achievements cannot be judged by age.

My dear teacher, do you want to quit the court and live in seclusion in the mountains?

Liang Fu knew very well that the other party didn't want to do that. But the blurred vision day after day and the increasingly difficult to measure instruments all told the other party that you are old and should not stay here anymore.

He felt sorry for his mentor, and he also knew clearly in his heart that the other party's achievements should not stop there.

Excited, Liang Fu couldn't help but think more.

He asked Shen Zheng nervously, "Master Shen, do you think they have made this thing?"