The tunnel did not stretch very far, maybe 30 yards. Four doors led off either side, making a total of eight.

Chance and Twig split up, examining the doors. Chance went down the left side of the tunnel while Twig headed for the right. All seemed unarmed. They were also all unlocked.

“I s’pose they figured their big electronic vault door was good enough, ay Chancy?”

Chance visibly winced at Twig’s remark.

“Don’t call me that.”

“Let’s open the first one,” Bixby said. “Do be careful, Mr. Chance.”

He nodded, gun at the ready as he turned the latch.

Everyone tensed as the door swung in on its hinges . . . revealing a plain square room filled with cogs and fly wheels piled high on the floor.

Tension leached out of the group when it became evident neither bombs nor guns would greet them.

“Hold on,” Chance said. “These are like the ones we saw in the outer room back there last night. I wager they’re the same items, Colonel.”

“I believe you’re correct, Mr. Chance. Lord Humphries, would you care to examine these objects? We believe they might be some metal knickknacks we observed the Septic Rats brushing with oil last night.”

The professor nodded and followed Chance into the room for a look.

Sharp said, “Mr. Twig? On to the next one, if you please.”

In short order, all eight rooms were opened and inspected. Each held different types of objects. One had screwdrivers, hammers and other tools. Another had watch and clock parts, and so forth. All the items were neatly stacked in piles on the center of the floor.

Rip found himself wandering back over to the professor, still in the first room. He had a soft spot in his heart for the old man, since Humphries publicly accepted Rip’s testimony about coming from another world.

Rip watched as the professor pulled a slim leather satchel off his shoulder and deftly threw several metal gears inside.

“Is that an interspatial satchel?”

Humphries looked up and smiled.

“Yes, it’s currently the largest such container the Lyceum has developed. However, we are uncertain how long it can hold onto the spatial abstractions stitched into the interior. Smaller items such as wallets have proven quite feasible, and we recently began putting them on the market. But a satchel is geometrically more difficult to sustain, I’m afraid. But we’re making great progress. Someday we hope to be able to offer Venture Society members rucksacks to take with them, if we can resolve certain issues.”

“I would imagine shipping companies would want them, as well.”

Humphries pursed his lips in thought and nodded.

“That is a singular idea. We are perhaps some ways out from being able to produce interspatial containers to any great degree, but if we can manufacture them on an industrial scale, you are quite right. They could seriously transform the shipping industry. Right now, larger containers have an unfortunate tendency to lose their integrity and collapse, with all the items falling out at a most inconvenient moment. I won’t deny there have been a few unfortunate accidents. Thus, we are being quite methodical about it all.”

Rip absently moved his hand to cover his back pocket, a look of concern growing on his face.

“Oh, I see you must have one of our recently produced interspatial wallets. Never fear. The smaller containers are quite safe. We’ve spent a few years working on this line of research, Sergeant. There has never been an accident with a wallet. At least, not a fatal one.”

“Well . . . I guess that does make me feel better. Changing the subject, but what do you make of all this scrap metal?”

“Baron Swathmoor was correct in his initial assessment.”

It took Rip a moment to remember that “Baron Swathmoor” was Bixby’s noble title. He had not heard it used very often.

Humphries continued and said, “These items have been dipped in ambient mineral oil, if I’m not mistaken.”

“Okay. What is ambient mineral oil?”

“Ambient mineral oil differs from its mundane cousins in several ways, the most noteworthy being it is far more conducive to luminiferous aether. In fact, it is considered by alchemists to be the most conducive substance for luminiferous aether on earth.”

“Ah. So, I take it that it’s rather hard to come by?”

“Indeed. That is an excellent deduction, Sergeant. In fact, if our presumptions are correct, all these items have been coated with more ambient mineral oil than we previously knew existed in Umbria. I would say 90 percent of the empire’s supply, not including the colonies, is in the Lyceum at this moment. And that consists of slightly less than two pints.”

“So . . . the Septic Rats got ahold of a lot more of this ambient oil stuff and coated all these items.”

“That is my working hypothesis, Sergeant Coulter. Yes.”

“And the only reason to coat inanimate objects in ambient mineral oil is to help the items go through the enhancement process?”

“Splendid observation. Truly they must teach the soldiers how to think on your world. I suspect you would make a fine professor here should you ever tire of working for the Venture Society. Yes, there is no reason to waste such a precious resource other than to use it for inanimate object enhancement.”

“But why have this street gang do it? Why down here in the Chelsea pump station of all places?”

“I find answering one question in scientific inquiry often leads to several more. The trick is to figure out which of the additional queries will lead you closer to the truth in a most expeditious manner. That part is not always easy.”

Rip rubbed his chin in thought.

In the distance, somewhere in the tunnel complex, they heard an explosion followed by the rat-a-tat-tat of automatic gunfire.

Everyone stepped out of whatever room they were inspecting and glanced at one another.

A woman’s wail reached their ears, high-pitched and filled with rage.

“Ah. That sounds like Liza,” Sharp said.

Bixby said, “Should we go and see if Lady Finley needs our assistance, then?”

“I think we should, my good fellow. Yes. I find that when one of the girls screeches like that, it’s typically a sign of duress.”

“Very well. Wrap it up quickly, everyone. Let us go lend a hand to the Fighters and the Verez sisters.”