As the sky grew brighter, the two mother stars climbed higher and higher. The mist of the forest, which appeared early in the morning, had long since cleared, replaced by beams of light from two mother stars streaming down through the leaves. The air was warm and moist, and the scent of lavender reached everyone's nostrils. The joyful songs of birds and springs were harmoniously matched to form a Sonata Of Nature.

In the distance they could see the massive figure of Maxwell Snow Mountain. It stabbed into the sky like a sharp knife, and the white snow at the blade reflected brilliantly in the light of the two mother stars. On the hillside there were countless craggy stones and a river of melted snow.

"Let's get over there quickly." William suggested. So they quickened their pace. They had no time to appreciate the sights passing behind them. They just wanted to gather enough energy quickly.

Checkpoint 24, 25 are cleared. Energy charge: 3.5%.

Watching the energy core gain more energy bit by bit, William became gradually happy.

They crossed one bridge after another, went over one hillside after another, and finally came to the foot of the snow mountain. Now William saw that there was some snow on the stones, too. The wind here was a little cold, making Ranran subconsciously wrapped her clothes.

"Master, do you need more clothes?" Asked Photon with concern.

"Oh, no, my coat heats itself. Don't worry about me freezing to death." William replied confidently, turning on the heating. He felt nothing but warmth, and never trembled again. "Is everybody ready?" He asked, while the others nodded. "Let's begin, then. It would take much less time to get over this mount than to go by road."

There were frequent visitors, so it was clear that there was a path winding upward. They found it easily and crawled along it.

The wind grew colder, blowing layers of snow. For half a minute or so the party could not open their eyes at all. There was simply too much snow in the wind. It only took ten seconds for Photon to change from red to white.

"Oh my God, this is so exciting!" Joked Photon, ignoring the heavy snow on his body. The laughter of the others was blown away by the cold wind.

Sierra was a little cold. "Sit in me," Natalie signaled. "No, thank you." Replied Sierra.

The wind was still howling. It was windy elsewhere today, too. Temperatures here were normally only about 20 degrees Centigrade cooler than those at lower altitudes, but today the difference could be as much as 35.

Snowflakes were dancing freely in the air. Some of the snowflakes even drew hexagonal flight paths, which amazed Ranran. William wondered how they did it.

Although the temperature was very low, to their relief, they had climbed to a height of 700 meters in ten minutes. Given the slope of the mountain, Ranran said the speed was ideal and there was no need to speed it up. "Well, then," Said Rebecca, "let's keep up this pace -- oh, look! What's that?"

The others looked in the direction she indicated and saw a black box by the side of the path. Pasted to it was a note which said,

Why is this box black?

"Do you even have to ask?" Said Peter, "Because, of course, the paint on the box absorbs most of the light and reflects very little of it. Plus, under the same intensity of light, it will be hotter than any box with other colors."

The box opened. Inside was a delicate notebook with four formulas written on Page 1,

On the back of the page, there were four more formulas.

And a date:

(0000 0111 0100 1001/0000 1100/0001 1111) 2

"What does this number in parentheses mean?" Asked Ranran, puzzled, "And subscript two?"

"Easy," Replied Sierra and Peter with one voice. Peter told Ranran that the dates inside were in binary numbers. William said to her, "These eight equations are expressions in Maxwell's equations, and the date is December 31st, 1865. Coincidentally, this coincides with the year in which Maxwell proposed the equation set. Why is that? Why is this one exactly the same when the planet's time counting system is different from ours? In addition, the inhabitants of this planet are not supposed to know about Maxwell the physicist, but why are his work here?" As he asked these questions, he felt more and more that there was something special hidden in this universe.

"Do we need to take this notebook?" Ranran asked, and the next moment Natalie saw the answer.

At the top of Page 1 of the notebook was a small print they had just overlooked,

Take me with you. I might come in handy.

So William gave it to the little robots in the backpack for safekeeping while they continued climbing. Now they were 1,500 meters above sea level, getting some more light from the two mother stars, so it was not as cold as at the foot of the mountain. "Feeling better at last," Rebecca replied.

Sierra replied, "Yeah, it's a good situation now. It's normal to see winds like that just now, but we don't see a lot of winds like that today."

"Yes," Said Peter, "because there has been a strong cold air current around here, but it's only temporary. It won't last long. But I expect we'll have the same gale as we just had on the way up."

Just then a thick layer of snow fell on William's clothes. When Ranran saw him change into a snowman for an instant, she burst out laughing. So did the others. William shook off the snow and joined in the laughter.

With the light of the two mother stars, the party was not as biting as before, but it was still very cold. At first they tried to clear the snow, but they soon gave up because every few minutes a lot of snow was blowing down on them. Rebecca even enjoyed being a snow plane a bit. She thanked him shyly when Peter complimented her on her beautiful white coat.

Suddenly, they found something.

"I found this!" Sierra picked up a cylindrical object on the ground. When they cleared the snow off it, they realized it was a circular magnet rotor. "But it lacks bearings. It can't turn." Ranran said.

Sierra thought for a moment and then said, "We must not have found the other parts."

"Yes." Natalie said she thought it might be part of a generator, but it was not clear if that was true.

However, the subsequent discoveries of William and Photon seemed to support Natalie's hypothesis. They saw something strange sticking out of the snow, dug through it, and found a carbon fiber shaft and a four-blade fan blade, respectively. William tried to put them together. It turned out that they were packed tightly enough to belong to different parts of the same object. Now, everyone was too excited to pay attention to the "snowstorm" that came every few minutes. It was not actually on the scale of a snowstorm on Earth; it was just snow from high winds. They sped up to search for the remaining parts.

They continued to climb, from 1,500 meters just now to 4,000 meters. The snow on the stones was getting thicker and thicker, as if trying to crush the stones, but they insisted on resisting the weight with their strong bodies. Both mother stars peaked a few minutes ago and were now losing altitude. They heard the sound of water, and William looked up. About five hundred meters above was the snow line, where flowed a clear river that they had just seen at the foot of the mountain. It was just that it went round the other side of the mountain and changed course again near the descent, so that they could only see part of it.

Ranran and Sierra found some coils and two electrodes. Peter saw a diode. The party put the pieces together, and a simple wind turbine appeared. There was a gust of wind near him, so William grabbed the generator and pointed the blades at the wind. The party watched as it span rapidly, driving the carbon fiber bearing and the magnet rotor, which made the diode glow blue. The wind became stronger and there were some snowflakes on it. William cleaned them up and saw that the diode was brighter.

"I wonder where this generator can be used." Said Rebecca.

"At least it can give us light." Said Photon, "It can also provide emergency electricity."

"We're almost at the top of the hill." William said, "Come on, everybody."

They climbed on against the oncoming wind. So far they had climbed about three quarters of the way up, with the remaining 1,500 meters or so being the hardest to climb. Not only was the wind strongest here -- stronger than that at the foot of the mount and the hillside -- but the road had vanished beneath them, so they had to climb on the stones. The planes and cars needed places as flat as possible, so the party had to be separated to let the planes and cars go to a gentle slope about 100 meters from where they were. William, Ranran and Sierra struggled over the stones. William gasped, sweat trickling down the ends of his hair, and the cold wind was gusting fiercely into his clothes. He reached out for Ranran, but she refused. "I can do it," She said firmly.

Footprints and tires left deep marks in the snow. The marks were glowing red by the two mother stars that were about to plunge into the horizon. The combination of the wind and William's weight caused some small stones to roll down the hill. The blades of the generators rotated constantly, and the diode provided them with constant light.

Photon pulled Natalie, Rebecca and Peter as they all climbed at full speed. Though the snow was slippery, they were still climbing slowly. The others, however, were climbing less smoothly. William's hands and legs were shaking from exhaustion, and every now and then he needed to sit on the ground to rest, wipe the snow and sweat from his hair, and get up to push on in the cold. Sierra almost missed her step and nearly fell on a platform dozens of meters below. She did not fall thanks to Ranran's quick hands and eyes. 300 meters, 200 meters, 100 meters... The top of the mountain was getting closer and closer. They had no time to rest their weary bodies, completely ignoring the wind and snow that struggled against them.

Finally, as soon as the two mother stars had completely disappeared, they reached the top of the mountain. It was a very open and flat plateau, with only white snow left. Looking around, lavender, once beautiful and distinct, now formed a huge purple blanket, covering the planet. The slopes on the east and south were gentle, while those on the west and north were steep. The party had just come up from the west side. If they took the two gentle routes, they would have saved about 20% of their energy but lost more time, even though this was already faster than taking the road.

But there was more than nothing on the top of the mount, Sierra told William. "Look, there's something there." She said, pointing to an extremely small pointed object to the south.

The party rushed toward there, leaving behind them their footprints and tire marks.