.
Outside the Garden House.
With Little Ox's appearance, Xu Yun finally seemed to "sense" something.
A look of three parts embarrassment, three parts surprise, and four parts panic crossed his face as he hurriedly put away the glasses.
"I'm sorry, Mr. Newton. I lost track of time. I'll get to it right away—"
Before he could finish, Little Ox interrupted him.
"What's that?"
"Huh?"
Xu Yun blinked and waved the glasses, playing dumb.
"As you can see, they're a pair of glasses."
Little Ox shook his head.
"Of course I know they're glasses. Sir Bacon's masterpiece from the mid-thirteenth century. My tutor, Mr. Rowan, has a pair of custom-made lenses that cost a fortune.
"I'm asking what that seven-colored light on the wall is."
At that, a perfectly timed look of relief appeared on Xu Yun's face. His acting put certain young heartthrobs to shame.
"Oh, you mean that seven-colored light? It's a dispersion of light phenomenon."
"A dispersion phenomenon?"
Xu Yun nodded and explained.
"In a distant Eastern country, there was a knight named Han Li, a man of extraordinary talent.
"He discovered that when sunlight passed through a triangular prism, it refracted and separated into seven main colors: red, orange, yellow, green, blue, indigo, and violet. He called this a dispersion of light phenomenon."
At Xu Yun's words, Little Ox froze for a moment, then his pupils suddenly shrank!
Anyone familiar with optics would know this.
For a long time, people had believed that white was the simplest color and white light the simplest kind of light.
It wasn't until someone used a prism to disperse sunlight in the seventeenth century that the secret of color was revealed.
And that person was—
Newton!
As it happened—
Little Ox had conducted his prism experiment on January 14, 1666, barely three months ago!
According to Little Ox's account in Opticks, his curiosity about light had begun in mid-June 1665.
While studying the telescope Stoke had lent him, he had suddenly noticed colors in the distorted images, which led him to begin investigating light.
Over the past while, Little Ox had tried convex lenses of all sizes, yet still hadn't uncovered the secrets of natural light.
And because of the problem of simplifying the binomial theorem, he had temporarily set the idea aside, planning to study it properly when he had time.
But who would have thought—
He would encounter the dispersion of light—or, rather—
The truth about light?
He took a deep breath and said to Xu Yun,
"Fat Fish, show me again. Hmm, I'll waive your meal fee for one day."
Seeing that the fish had taken the bait, Xu Yun's lips curled in a barely perceptible smile, while his hands obediently did as instructed.
He turned the thickest edge of the glasses toward the sun and adjusted them to a particularly precise angle.
A moment later—
A small cluster of rainbow-colored light appeared once more in the shadow.
Normally, there were two main ways to perform a dispersion experiment:
One was with a mirror and water; the other was with a triangular prism.
But if your glasses prescription was strong enough, the edge of the lens could also create a temporary dispersion effect.
That was because nearsighted glasses were concave lenses, thicker on either side. This was especially true of high-prescription lenses, whose optical properties gave them the qualities of a prism.
When light struck the lens, each color refracted differently, separating the various colors in the light source. They then entered your eyes, creating a rainbow.
That was also why some people saw colors splitting apart along the edges or outlines of objects near the edges of their lenses—the theoretical basis was the dispersion of light.
What, you asked what the technical factor was?
Of course, it was that the optician had done a poor job.
"Red, orange, yellow, green, blue—wait, that's cyan, isn't it? Cyan, violet... God!"
Watching the sunlight split into a rainbow of colors as it refracted through the lenses, Little Ox's lips trembled with excitement.
As mentioned earlier, Little Ox was a devout believer, and he was convinced that the world must contain certain codes left behind by the Creator, reflecting the truth of the universe.
The seven colors produced by dispersion clearly fit the bill.
He suddenly turned around and stared fixedly at Xu Yun.
"Fat Fish, did Sir Han Li explain this phenomenon?"
Xu Yun opened his mouth, ready to explain the causes and effects of dispersion, but found that he couldn't make a sound, no matter how hard he tried.
At the same time, another prompt box suddenly appeared before his eyes.
It contained no words, only a flashing yellow exclamation mark.
It was obvious.
For some reason, a certain "rule" limited how much Xu Yun could reveal to Little Ox. Perhaps he had to take things one step at a time.
But when he thought about it, that made sense.
Otherwise, Xu Yun could just tell Little Ox the vector equation F=-(GMm/r^3)r and be done with it, couldn't he?
After thinking it over, Xu Yun said,
"Mr. Newton, Sir Han Li only discovered the dispersion of light phenomenon. He never offered much of an explanation for its principles.
"After all, it was a minor discovery in the course of his eventful life.
"Later, Sir Han Li disappeared during an adventure and was never heard from again.
"But before he vanished, he once said something related to the dispersion phenomenon."
Little Ox immediately perked up and pressed him.
"What did he say?"
Xu Yun paused for a few seconds, then ventured,
"He said... according to his guess, sunlight might disperse because the light of each color had different properties.
"It's like a school of fish made up of countless fish. To the naked eye, it looks like a huge, murky mass, with too many fish to count.
"But if you filter them through screens with different-sized holes, you can separate the big fish from the small ones.
"If you add more screens, you can separate out fish of even more sizes, including fry.
"Perhaps the dispersion of light works the same way.
"Maybe the different colors have different 'sizes,' and that's why they show up as a rainbow after passing through some unknown filter."
Little Ox nodded thoughtfully. After pondering for dozens of seconds, he said,
"I think I understand. But, Fat Fish, I have a question."
"What is it?"
Little Ox glanced up at him.
"According to you, a school of fish might include big fish and fry. That's a question of categories within the broader group of fish.
"But for a school of fish to survive, it needs a suitable external environment, doesn't it?
"For example, the sea, lakes, or rivers. Obviously, fish can't survive on land or in the sky.
"So does that mean—
"Light also needs a certain environment, or perhaps certain conditions, in order to travel?"
Xu Yun: "..."
Hello? I'd like to report a cheater! Someone here's using hacks!
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