Page 103 of Murder on Black Swan Lane

Tyler assembled the bottles, along with a selection of empty glass vials. “You still haven’t answered my question as to how you intend to stop Lowell.” He set the tray down on the worktable. “Forgive me for pointing it out, but it seems there are more pressing things to be doing at this moment. Why are you spending time analyzing the compound?”

“Because I am curious.” The earl squinted into the lens and adjusted the reflectors. Charlotte would likely also say it was because he was trusting his intuition. “Move the lamp a bit to the left.”

The polished metal caught the light and angled a brighter beam onto the slide.

“And knowing the exact science behind his creation may help in understanding exactly what he is up to.”

Tyler made a skeptical face.

“It also may help pinpoint the location of Lowell’s secret laboratory. That’s the key to ending this—if we can lead Griffin to where he is working, the evidence will speak for itself.”

The earl leaned back. “Put a bit of the remaining sample in one of the testing vials and add one drop of spirits of salt.”

They both watched intently as the liquid fell onto the powder.

“Nothing,” murmured Tyler after a long moment.

“Excellent.”

“You are pleased?”

“Exceedingly,” answered Wrexford. “Attach the adapter to the lens and I shall show you why.”

The procedure increased the microscope’s power of magnification. The earl refocused on the sample and gestured for Tyler to take a look.

“What does the greenish powder look like to you?”

The valet hesitated. “If I didn’t know better, I’d say it was ground glass.”

“Sometimes the most obvious answer is the correct one,” answered Wrexford. “I suddenly remembered reading an obscure text by Newton on the properties of glass, and how it could serve as a stabilizing substance.” He contemplated the sample in the vial. “I think we can safely speculate that Lowell has come up with a formula for an improved mercury fulminate that may be used in practical applications.” A pause. “Such as weaponry.”

Tyler let out a low whistle.

“One other thing—that particular shade of green is typical of wine bottles from the Rhine Valley near Mainz.” He thought for a moment. “Perhaps you’re right—identifying the last ingredient can wait. Right now, I want you to start checking on whether there are any warehouses here in London that are used by German importers from that region.”

“Yes, milord!”

“While you are engaged in that task, I will pay a visit to Mrs. Sloane,” went on Wrexford, “and see if she can remember any details from her husband’s last days that might indicate where he was working.” Fatigue gave way to a rising sense of anticipation. “I think we’re closing in on the bloody devil.”

CHAPTER 23

“Given the events of the past evening, isn’t it rather early for you to be up and about, Lord Wrexford?”

“I could ask the same of you, Mrs. Sloane,” he replied dryly. When she didn’t move from blocking the doorway, he added, “Might I come in? Or am I persona non grata for corrupting the tender morals of children?”

Heaving an inward sigh, Charlotte stepped back into the foyer and gestured for him to enter. It was ungracious to feel angry with him. She would never have learned the truth about Anthony without his resolve and resourcefulness.

But perhaps that was part of her mixed emotions. She didn’t like feeling beholden to anyone.

“I thought aristocrats never rose until well after noon,” she murmured as he followed her into the main room.

“By now you should know I rarely do what is expected of me. A flaw, I know, but there you have it.”

She relented and allowed a faint smile. “I neglected to thank you for your efforts. You were impressively intimidating, sir. Had I been facing your fearsome phiz, I would have been quaking in my boots.”

“Bollocks,” quipped Wrexford. “You have never been the least intimidated by me. It’s very lowering.” He looked around. “Where are the weasels? Sleeping the blissful sleep of Innocents?”

She strangled a laugh. “You really must stop calling them that. They are no worse than other lads their age.”