zupoxs.cc 
Father didn’t reply.Near the end of the silent drive，Yuanyuan took out a large envelope and handed it to him.
“What is it？”Father asked，uncomprehending.
“Housing deeds and a key.I bought you a villa by Lake Tai.You’ll be able to go back to the south after you retire.”
Father gently slid the envelope back in her direction.“No，child，I’m going to live out the rest of my life in what remains of Silk Road City.Your mother and I have buried our youth and dreams there.I can’t leave.”
Beijing glittered to its heart’s content in the summer night.Gazing at the gorgeous sea of lights，Yuanyuan and her father both thought of soap bubbles.What was this boundless radiance trying to show to them：the weight of a life，or the weightlessness？
7
One day，two years later，the mayor received a call in his office from his daughter.
“Happy birthday，Baba！”
“Ha，Yuanyuan，is that you？Where are you？”
“Not far from where you are.I’ve brought a birthday present！”
“Hey，it’s been years since I remembered my birthday.Come home at noon，then.It’s been a month since I’ve gone home myself.There’s just the housekeeper there to keep an eye on things.”
“No，I’ll give you the gift right now！”
“I’m at work.The weekly city council meeting is about to start.”
“Not a problem！Open the window and look up！”
The sky today was clear in every direction，a limpid blue，rare weather for the area.The rumble of an engine came from the air；the mayor saw that an airplane was slowly circling in the sky above the city，striking against the blue backdrop.
“Baba，I’m on the plane right now！”Yuanyuan shouted through the phone.
It was an old-fashioned，propeller-driven biplane.In the sky，it looked like a giant bird gliding lazily.Time flashed backward；a familiar sensation struck the mayor like lightning.He shivered all over，as he had done twenty years ago.His daughter had asked him if he was cold.
“Yuanyuan，what—what are you doing？”
“Here’s the gift，Baba，pay attention to the bottom of the plane！”
The mayor had noticed earlier that a big hoop hung from the body of the plane.Its diameter was greater than the length of the plane；clearly，it had unfolded into position only after the plane took to the air.Taken together，the plane and the hoop looked like a flying ring.Later，he’d learn that the hoop was constructed like the one Yuanyuan had used to break the Guinness World Record，made of a tube of lightweight metal filled with the nigh-supernatural FlySol.A film of FlySol stretched across the hoop，and innumerable small holes allowed FlySol to continuously flow out of the thin tube that formed the hoop.
An astounding sight appeared.Behind the giant hoop，a bubble was emerging！Refracting sunlight，its form wavered at the edge of visibility.The bubble swelled rapidly；soon，the plane compared to it was only a sesame seed on top of a transparent watermelon.
In the marketplace below，everyone had stopped to look up.People were starting to run out of the city government headquarters building to watch.
The plane circled slowly above the city，tugging the enormous bubble behind it.The bubble had slowed in its growth，but not completely.Gradually，it came to occupy half the sky.At last，it broke loose from the hoop beneath the airplane，floating independently in the air.
“This is my present，Baba！”Yuanyuan shouted excitedly through the phone.
Huge patches of light shimmered in the blue heavens，as if the entire sky were a slick piece of cellophane being crinkled by invisible hands under the sun.On close inspection，the flashes of light delineated an enormous，transparent sphere that took up most of the sky.The people below had to turn their heads nearly one hundred and eighty degrees to see it in its entirety.It looked as if the mirror of heaven were casting a crystalline reflection of the Earth below.
The city began to grow agitated.Traffic jams formed in the thoroughfares.
The enormous bubble slowly descended from the sky.Once it was at a sufficiently low altitude，the people below could even see the city’s skyscrapers mirrored on the bubble’s surface；as it undulated in the wind，the buildings twisted and distorted，like a kelp forest under the sea.The broad bubble membrane pressed down inexorably.People instinctively shielded their heads with their arms.When the bubble touched the ground，those exposed outside felt a brief itch on their faces as their bodies passed through the membrane.
The bubble hadn’t popped.Instead，it had formed a spherical dome nearly ten kilometers in diameter with the ground.The city and the surrounding industrial plants were now trapped in the bubble！
“It wasn’t on purpose，it really wasn’t！”Yuanyuan said into the camera.“Under normal conditions，the bubble would have floated away in the breeze.Who knew today’s wind would be so much weaker than usual？That’s why it fell and covered the city！”
The mayor watched the emergency report，which had interrupted the city television station’s normal programming.He saw that his daughter was wearing a leather aviation jacket，open at the front to reveal a blue work uniform underneath.Beneath her was the old-fashioned biplane…time flashed backward again.So alike，they look so alike…the mayor’s heart melted，tears spilling from his eyes.
Two hours later，the mayor and the newly established emergency team drove to the bubble wall at the city outskirts.Yuanyuan and several of her engineers were there，well ahead of them.
“Baba，isn’t my superbubble amazing？”Yuanyuan had lost her earlier panic，her face alight with inappropriate excitement.
The mayor paid no mind to his daughter，raising his head to consider the bubble’s surface.The vast sheet of membrane shimmered in rainbow colors under sunlight，intricate patterns of diffraction on its surface shifting and morphing hypnotically in a bewitching sea of all the universe’s colors.The membrane was transparent，so that the outside world seen through it was coated with a layer of iridescence too.A certain distance up，the iridescence disappeared；from the air，it would be impossible to see the membrane.
The mayor reached out a hand and carefully touched the superbubble.The back of his hand itched，very faintly：it was already on the other side of the bubble.The membrane might only be a few molecules thick.He drew his hand back through；the membrane instantaneously returned to its original form.The pattern of iridescence there was unchanged，as if it had never been interrupted.
The others also began to touch the membrane，then waved their hands in an attempt to tear it，then at last devolved into flailing punches and kicks…but none of it made a difference to the membrane.Every assault passed through the bubble without resistance，after which the membrane restored itself perfectly.With a wave of his hand，the mayor halted everyone’s futile efforts.He then pointed to the highway in the distance；the others saw that the traffic on the highway was passing through the membrane undisrupted，even at their high speeds.
“It’s like a soap bubble membrane：solid objects can pass through，but not air，”said Yuanyuan.
“Air not being able to pass through is the problem.The air quality in the city is rapidly deteriorating，”the mayor said，glaring at his daughter.
Everyone looked up and saw that an enormous white dome-shaped cap had appeared in the sky above the city.The membrane was trapping the smoke from the city and industrial plants in the mold of the superbubble.If one were to observe the city from a distance right now，perhaps they’d be seeing a towering hemisphere of milky white.
“We may need to shut down the power plant and the chemical plant to slow down the rate of pollutant release，”said the leader of the emergency team.“But the most serious problem is the rising temperatures inside the bubble.Right now，the city is effectively inside a sealed greenhouse without air exchange with the outside world.It’s the middle of summer，and the heat from the sun is building up quickly.According to our calculations，the temperature inside the bubble will eventually peak at sixty degrees Celsius！”
“Up to now，what methods have we tried for destroying the superbubble？”asked the mayor.
“An hour earlier，we had army aviation people fly their helicopters through the top of the bubble，trying to use the propellers to tear it open，but it didn’t work，”answered an officer from the local garrison.“Then we set explosives where the bubble met the ground.The explosion only made the bubble ripple a while，without causing any damage.Even more incredibly，the membrane instantaneously extended down into the blast crater，traveling right along the bottom without any gap！”
“How long will it take for the bubble to burst naturally？”the mayor asked Yuanyuan.
“Bubble rupture is primarily caused by evaporation of the fluid membrane.This substance has an extremely slow rate of evaporation—even with sunny weather，the bubble will take five or six days to pop，”Yuanyuan answered.To her father’s outrage，she sounded full of pride.
“Then we’ll have to evacuate everyone，”the leader of the emergency team said，sighing.
The mayor shook his head.“I won’t take that step until we absolutely have to.”
“There’s another way，”said an environmental specialist.“Hurry and have a lot of long tubes made，the wider the better.Place the tubes with one end outside the bubble and a high-power ventilation fan on the other end，and we can exchange air with the outside world.”
“Haha—”Yuanyuan started to laugh，startling everyone around her.Surrounded by angry looks，she was laughing so hard she couldn’t stand upright.“That idea’s—that’s hilarious！Haha—”
“This is all your fine work！”the mayor thundered.“You’re going to take responsibility and pay back all the losses you’ve caused the city！”
Yuanyuan looked up at the sky and stopped laughing.“I know，I’ll pay up.But I just thought of a simple way to pop the superbubble—burning.Dig a trench one to two hundred meters long where the bubble meets the ground，pour it full of fuel，then light it.The fire will make the membrane evaporate much faster.The bubble should burst after about three hours.”
The mayor ordered the emergency team to do as Yuanyuan explained.A wall of fire more than a hundred meters long sprung up on the city outskirts.As the row of furious flames licked at the bottom of the superbubble，strange colors and shapes shimmered in the membrane.The patterns of color revealed that the FlySol from other parts of the bubble was rushing over to replace what had evaporated from the fire，as if the portion being burned had become a giant whirlpool，sucking gorgeous，beguiling floods of color from every direction to disappear into the flames.Their black smoke pressed upward along the bubble’s inner surface，gathering into an enormous black hand pressing down，terrifying the millions of city-dwellers within the superbubble.
