The White Bone Mark

He opened the offline map on his phone and went to an area downtown where hardware and electrical equipment stores were clustered. Before long, he found what he wanted in one of the stores: a 7.5-kilowatt air compressor that ran on 220 volts.

Su Ming picked out a pile of air hoses, quick-connect fittings in different sizes, solenoid valves, and control coils. He also stocked up on cables, circuit breakers, cable lugs, hydraulic crimping pliers, electrical tape, and all sorts of other odds and ends he could use.

As usual, Su Ming left a message on the wall in spray paint, then activated the summoning array. There wasn't much to transport, and the transfer went smoothly. He felt he was growing more and more adept at controlling the summoning spell.

An equivalent amount of material was consumed on the otherworld side. Iron and steel were actually fine, but copper was genuinely limited. The air compressor's electric motor alone used up quite a bit this time. When he had taken cables before, Su Ming had deliberately chosen aluminum wire to reduce copper consumption.

The bodies of both new energy vehicles were made of aluminum alloy, so there was still enough aluminum for now.

Su Ming had originally planned to look for equipment to make deionized water next, but while sorting through the materials, he discovered a problem: there was no resin on the otherworld side!

Su Ming hid the motorcycle and Little Spiky Head, then went to discuss it with White Bone.

"Do you absolutely need it?" White Bone asked.

"A water purification system that uses ion exchange with resin is the simplest equipment to make," Su Ming explained.

"No, I'm asking about the deionized water. Do you absolutely need it?"

"Desalinated water produces a lot of scale," Su Ming replied. "It's one thing for it to reduce the performance of the boiler and steam engine, but after a while, it'll damage the equipment. Though if we're just escaping, it should be fine."

White Bone thought for a moment. "We can't be shortsighted. Our enemies won't let us go so easily. We don't just need to escape; we also need to be able to handle the pursuit afterward. And..." She paused. "The Temple Knights aren't the only ones we'll have to face. Let me find a way to deal with this. You should rest first."

It was now the third night since they had started the steam escape plan, and Su Ming had spent another full day working.

He nodded, dug his toiletries out of his suitcase, freshened up briefly, and went to sleep.

When he woke up the next morning, a skeleton servant brought him a cup of water.

Su Ming drained it in one gulp and smacked his lips. The water tasted strange.

"What kind of water is this?" he hurriedly asked White Bone.

He could now initiate mental synchronization with White Bone himself, but he couldn't maintain it for long, unlike White Bone, who could leave it running unattended.

"Deionized water," White Bone replied. "There are actually methods for it recorded in alchemy. You can do it by preparing different alchemical potions for different kinds of water."

Su Ming had also considered chemical methods, and chemical supply stores were easy to find on Earth, but there were no corresponding materials here. That was the problem. If he had the materials, why would he need to transfer anything?

Find lime in the otherworld first, then map a pile of lime over from Earth? Wouldn't that be a pointless waste of effort?

Fortunately, the otherworld's alchemy had a similar system.

"Then is that problem solved?" Su Ming asked.

"No, my potions are limited. They're probably only enough to produce a tenth of the water needed to fill the tank. Desalinating seawater consumes a lot of magic power, so I've stopped."

"That's only enough for testing. Once the steam engine is running for real, the water will need to be replenished continuously!"

"That's enough, then. We'll have plenty of purified water tonight," White Bone said.

According to the plan, they would test the steam engine assembly during the day. If it succeeded, they would begin their escape that night. White Bone's kin could arrive at any moment, so they had to move straight from one step to the next and stay as far ahead of schedule as possible.

Su Ming connected the air compressor, filled the boiler and the recirculating cooling system with deionized water, and tested each subsystem one by one. Whenever something was wrong, he adjusted it until everything was working properly.

That alone took half a day.

Next came heating the boiler.

Su Ming wasn't actually clear on some of the details of the boiler, but modern equipment like this was already highly integrated. Painted metal casings enclosed the components in neat, square shapes, and all Su Ming had to do was tap the touchscreen a few times.

As for the hard work of loading fuel, that naturally fell to the tireless zombies.

The small unit was relatively quick. In less than half an hour, the pressure reached the minimum threshold. He went to the steam engine and flipped the switch.

Steam shrieked into the cylinder. After a fitful start, the engine gradually smoothed out, and the massive flywheel began to pick up speed, slowly but steadily. Once it had accelerated for a while, a signal lit up on the engine control console.

Following the parameters recommended in the manual, Su Ming engaged slow ahead.

The propeller began to turn, though not very fast.

"The next test has to be done in the water," Su Ming told White Bone. "This system is designed for the torque it encounters in water. It can't run too fast without a load."

The undead scholar sent a zombie forward, intending to test the propeller's strength, but Su Ming stopped her.

"Don't force it. You'll damage the hydrodynamic structure of the blades," Su Ming explained. "All the machinery is working properly now. Once we're in the water, I can increase both the boiler's firing rate and the propeller's speed. Running at full power, it can propel you at fourteen knots."

"Amazing," White Bone said with feeling. "Just a few leaves of grass can provide a continuous output of powerful force."

"In my eyes, your magic is the more amazing thing," Su Ming said.

"Whether it's magic, arrays, or alchemy, achieving the same thing here would come at a much greater cost. You've won in this respect, visitor from Earth."

Su Ming began shutting down the equipment, releasing pressure and letting each part cool. A few pipes needed additional welding, and some screws needed tightening, but overall, the startup had gone better than expected-even though the shipyard had already tested and adjusted the system.

Su Ming went back to work, while White Bone remained silent, and he didn't know what she was thinking about.

After quite a while, she suddenly spoke. "Mr. Su Ming, can you promise me something?"

"Hm?" Su Ming stopped what he was doing, puzzled by the emotional fluctuations he sensed.

The first time Su Ming had felt that this undead lady had emotions too was when Archbishop Stanton had burned the vegetation outside the Tower of White Bone. But that was nothing compared to White Bone now.

"If we survive, you must take me to see more things like this and reach places we've never seen before," the scholar said earnestly. "That is our request."

Su Ming found it strange. White Bone's emotions didn't seem quite right, and this wasn't the time to discuss such things. But he still answered, "I can promise you that for as long as I remain in this world. But my goal is to return to Earth. Would I take you with me then too?"

"I can follow," White Bone replied.