Young Newton had terrible sleeping habits; his snoring rivaled the sound of someone grinding their teeth.
But perhaps because a full day of labor had left him exhausted, Xu Yun eventually drifted off into a heavy sleep.
The night passed uneventfully.
Who knew how long later, but a sudden burst of birdsong came from outside the window.
Xu Yun opened his eyes lazily, scratched his messy hair, stretched, and yawned himself awake.
It was winter on the British Isles, and the morning air was bitterly cold and damp. When Xu Yun exhaled, a cloud of white mist quickly appeared before him.
Then he suddenly remembered something and turned to look to his right.
Little Ox's bed was empty. The old master had clearly been awake for quite some time.
The sky was already growing somewhat bright. It was probably around half past six in the morning, or seven at the latest.
Back home, some struggling writers who stayed up all night typing might only just be going to bed at this hour.
Xu Yun pressed his hands together in front of his mouth and blew into them, rubbed his face briskly, then scrambled out from under the covers. Anyone who'd worked a day job knew that in winter, escaping the bed's seal required a single swift movement, before the blanket realized what was happening.
After tidying his clothes, Xu Yun gently opened the bedroom door and peered out.
Sure enough.
Little Ox sat at the desk outside, head bowed as he wrote furiously, apparently working through some sort of calculation.
Hearing the bedroom door, Little Ox looked up and nodded toward the tea table by the entrance.
"There's bread on the table. Just one piece. Eat breakfast, take a little rest, then go check the orchard."
Little Ox hesitated. Before Xu Yun could reply, he changed his mind.
"Never mind. It's your first day doing this, so I'll show you the whole routine. Starting tomorrow, you can go on your own."
Xu Yun nodded.
"Understood, Mr. Newton."
He glanced at Little Ox, who had already returned to his writing, and continued.
"Mr. Newton, I'd like to go get some water to soothe my throat. I slept all night, and my mouth's a little dry."
Little Ox didn't answer this time, only giving a soft hum.
With permission granted, a strange glint flashed in Xu Yun's eyes. He picked up a wooden cup he'd carved the day before and headed outside.
There was a slightly dilapidated water tank beside the garden house. Judging by its age, William had probably made it. It stood beyond the view of the window behind Little Ox.
Xu Yun strolled over, scooped up some water with the wooden cup, and, without minding the cold, poured it straight into his mouth.
He began gargling.
It had to be said that before the nineteenth century, the mainstream customs of Huaxia were far superior to Europe's.
For example, though people in ancient Huaxia had no toothbrushes, they had many ways to clean their mouths.
The Book of Rites, for instance, recorded, "At the first crow of the rooster, all should rinse their mouths." Common oral-hygiene products in ancient Huaxia included wine, vinegar, salt water, and tea.
Wine, vinegar, and salt water had antibacterial properties, while tea leaves were rich in fluoride.
Fluoride helped prevent cavities and could also clean the mouth and protect the teeth.
Later, willow twigs and pig bristles, among other things, gave rise to the famous early prototypes of toothbrushes.
But ancient Europeans were different. They generally didn't brush their teeth or bathe—especially the English.
Even now, many English people still didn't have the habit of brushing their teeth, so oral health remained a serious problem in Britain.
Of course.
That had a lot to do with their political and cultural background, but that was a story for another time.
In short, from the perspective of a modern person, Xu Yun was happy to respect customs that did no harm, but he couldn't bring himself to put up with not brushing his teeth or washing his face.
So he had to take every opportunity to keep himself as clean as possible.
If he got the chance, it would be worth correcting Little Ox and William's habits, too.
There was no direct evidence from later generations that their lifespans were linked to not bathing or brushing their teeth, but correcting those habits could only help. Living a few extra months would be a bonus, wouldn't it?
After rinsing his mouth, Xu Yun splashed a little cold water on his face.
He patted it on a few times.
The icy sensation soaked into his skin, waking him up considerably.
Once he'd washed up, Xu Yun didn't hurry back. Instead, he looked up at the sky.
"Wow, not a cloud in sight, bright and sunny. What a perfect day for fishing."
Xu Yun rubbed his hands together and chose a corner where sunlight and shade each covered half the wall.
He took off his nine-hundred-degree glasses, then...
He did nothing at all. He simply pricked up his ears and listened closely for any sounds from the garden house entrance.
Meanwhile, inside the house.
At that moment, Little Ox was scribbling calculations on paper at high speed:
(A+B)m/n =(P+PQ)m/n = Pm/n ＋(m/n)＋[(m-n)/2n])＋[(m-2n)/3n])＋[(m-3n)/4n])＋...
"Hmm, if I write it as e^(n*ln(1+1/n)) and use the indeterminate form 0/0 in the exponent to turn it into 1... Damn it, that doesn't work either!"
As his pen came to a halt, Little Ox irritably tugged at his hair.
He puffed out his cheeks and let out a breath.
At this time yesterday, he'd encountered Xu Yun, who had fallen from the sky, and all the events that followed had taken place.
There was nothing particularly special about the incident itself. It was just a chance encounter, nothing more.
But the image of Xu Yun falling had overlapped with a question Little Ox had been pondering.
Why did things fall downward when they lost their support, instead of floating upward?
Of course.
That question hadn't first occurred to him yesterday. Little Ox hadn't even been the first to come up with it.
But Xu Yun's appearance had made the question stick more firmly in his mind.
And unlike other people...
Little Ox already had a few leads on this mysterious "force." That was Kepler's Three Laws.
According to Kepler's Three Laws, all the planets in the Solar System moved around the sun in elliptical orbits.
So many people, including Little Ox, suspected that the Inverse square law and Kepler's Three Laws must be connected in some way.
The problem was that proving one from the other required a mathematical tool that didn't yet exist. Little Ox called this tool Fluxions: a method for finding the relationship between the fluxions of known related quantities, as well as the inverse operation.
Little Ox had completed part of his derivation, but he'd gotten stuck trying to simplify the binomial (P+PQ)^m/n.
This was already his sixth attempt to simplify it, and he still couldn't expand it into a simple series.
If he couldn't get past this hurdle, how could he hope to explain that mysterious "force"?
As frustration set in, his thoughts naturally began to wander.
In a few hours, they were supposed to leave for Uncle William's house.
He really wanted to give Lisa a kiss.
He wondered how much food his uncle had left, especially now that there was another mouth to feed—Fat Fish.
Wait!
As he thought it over, Little Ox suddenly realized something and quickly turned his head a few times.
Where was Fat Fish?
It had been more than half an hour since he'd gone out to get water. He should have been back by now. Surely that kid hadn't gone all the way to the River Thames to fetch water?
Thinking of the living expenses the Oriental had agreed to pay him, Little Ox could no longer sit still.
He quickly put down his pen and strode out of the house.
Creak—
After opening the door, Little Ox headed toward the water tank with practiced ease.
But as soon as he rounded the corner, he saw Xu Yun crouching on the ground in the Asian squat, holding his glasses in one hand.
Seeing that Xu Yun wasn't in trouble, as he'd imagined, and was even showing signs of slacking off, Little Ox's temper flared at once.
"FU—"
But before he could get the word out, he choked it back.
What stopped him wasn't the censorship system of the Qidian Chinese website. It was—
A small but unmistakable patch of
seven-colored light
in the shadow of the wall behind Xu Yun!
Before you continue