“It was the same drug that we used on you, Miss Dean,” Alcina said. “After Mrs. Crofton was unconscious, the housekeeper sent a note to me, informing me of what had happened. We had made a bargain, you see. I paid her a great deal of money to ensure that she would notify me if anyone came around asking questions. I sent Jasper to collect Mrs. Crofton.”

“Gaining control of Lady Hollister must have been a simple matter,” Virginia said. “It did not require any talent to manage her, and through her, the entire household. But Hollister would have been another problem altogether.”

“My father was a rather dangerous man.” Alcina smiled. “But when you discover a man’s passion, you know what is required to control him.”

“How long did it take you to realize that he was raping and murdering young prostitutes in that mirrored chamber below the mansion?” Virginia asked.

“Not long at all. I realized almost at once that something very odd was going on, of course, but Hollister kept his secrets surprisingly well. It was not as if he went about practicing his hobby every Saturday night. He often went weeks, sometimes months, between kills. But eventually the fever would come upon him and he would go off into the night to find a suitable victim.”

“How did you learn the truth?” Virginia said.

“Jasper followed him one night,” Alcina said.

“When I realized what he was doing with the street girls, I began to conceive my grand experiment,” Welch said. “I had already discovered Mrs. Bridewell and her clockwork curiosities, and I had developed my theory. I was anxious to perform some experiments with the devices.”

“You convinced your father to let you run those experiments on his victims,” Virginia whispered.

“He was very enthusiastic about the plan when he realized that I was his son. He certainly got into the spirit of the experiments, I must say.”

Virginia did not think she could be any more horrified than she already was. But a new chill slithered down her spine. She stared at Welch.

“You helped your father murder three street girls in the basement of the Hollister house, and then you murdered Mrs. Ratford and Mrs. Hackett,” she said.

Welch scowled. “You speak as if I were a common criminal. I am a scientist. I have been carrying out experiments with glasslight for years, but it wasn’t until I accidentally discovered Mrs. Bridewell’s inventions that I was able to conceive of a way to realize the full potential of my work. My father and I worked together to perfect the process of infusing the death energy into the mirrors.”

“Why did you stop using streetwalkers as your victims?” Virginia asked. “Why take the risk of killing Ratford and Hackett?”

“It occurred to me that if the subject that was to be extinguished—”

“You mean the murder victim,” Virginia said.

Welch ignored the interruption. “If the subject was possessed of a talent that was sensitive to glasslight, the energy given off at death would have a natural affinity for mirrors and be far more readily absorbed by the glass.”

Mrs. Crofton glowered at him. “What is the purpose of all this murdering? Why are you trying to infuse paranormal energy into mirrors?”

“Of course you do not understand,” Welch said impatiently. “You are a housekeeper, not a scientist.” He turned to Virginia. “But surely you, with your great talent, can perceive the potential of my work, Miss Dean.”

“As far as I can tell, your only goal is death by glasslight,” she said. “Where is the use in that? A gun would certainly be more efficient.”

“Bah. You are as ignorant as your housekeeper. This is where you come in. Over time this chamber has absorbed a vast quantity of energy. It only remains to find a way to ignite the power in the mirrors.”

“You think you can do that by murdering me and infusing my energy into the glasses?”

“Indeed. What’s more, if my theory is correct, I will be able to construct other engines like this one.”

“Good grief,” Virginia said.

“Once I learn how to harness and control the energy in the mirrors, there is no limit to what I can achieve. I stand on the brink of creating amazing weapons that will bring down armies yet leave buildings, roads and factories untouched.”

“In other words, you are crafting a very large psychical cannon,” Virginia said.

“Advanced weaponry is only one potential aspect of my work,” Welch said. “Power is power. It can be used for an infinite number of purposes. A psychical scientist with a talent for engineering might find a way to use my glasslight generators to power ships and trains. One day someone might use one of my generators to unlock the secrets of the paranormal spectrum. Who knows what might be accomplished if mankind succeeds in comprehending the workings of the paranormal.”

“And all of it powered by death,” Virginia said. “Something tells me that is not going to generate a lot of enthusiasm in the general public.”

Welch’s face tightened with anger. “The public need never know that my Great Engines require the death energy of an occasional glasslight-talent or two to ignite them.”

“A few glass-readers will disappear here and there, and no one will even notice. Is that the plan?”

“The reflective properties of the mirrors will magnify the results of each subject’s contribution,” Welch assured her.

“How do you plan to control your looking-glass engines? You said yourself that you do not know Mrs. Bridewell’s secret for releasing the energy stored in glass by mechanical means.”

“I am still working on that aspect of the problem,” Welch admitted. “But it is only a matter of time before I reason it out. Meanwhile, igniting the energy in this chamber will have one very immediate and useful effect. It will vastly enhance the power of each of the objects in this room.”

Mrs. Crofton looked disgusted. “You’re turning these artifacts into weapons?”

“Weapons that are far more powerful than Mrs. Bridewell’s toys,” Welch assured her. “One can only imagine what devices I will be able to create in this chamber once I have ignited the mirrors with the energy given off by a high-level glasslight-talent like Miss Dean. And that is just a starting point. Future applications are unlimited.”

“Mirrors break rather easily,” Virginia said.

“If that was intended as an attempt at humor,” Alcina said, “perhaps you don’t understand why you are here today.”

“I’m well aware of why you brought me here,” Virginia said. “Your brother wants to murder me in this room because I’m the strongest glass-reader he has ever come across. There is a lot of energy trapped in these walls. He thinks he can use me to ignite it.”

Alcina looked amused. “You are impressively calm about the situation in which you find yourself, Miss Dean.”

“So are you,” Virginia said. “Why are you allowing Welch to use this fantastic collection and these mirrors for his grand experiment?”

“The more powerful the mirrors in this room become, the more they enhance not only the objects but also my talent.”

“Surely you can see that your brother is mad as a hatter,” Virginia said.

Alcina smiled. “Like father, like son.”

“One last question,” Virginia said. She looked at Alcina. “What went wrong that night at the Hollister mansion?”

“Everything went wrong that night,” Alcina said, her face twisting with fury and remembered frustration. “Jasper and I always intended to kill Hollister, but we did not plan for him to die that night. We wanted him to suffer.”

“And, of course, make a contribution to my Great Engine,” Welch added. “Father was a fairly high-level glasslight-talent. Not nearly as powerful as you, Miss Dean, but certainly strong enough to enhance the store of energy in this chamber.”

“The plan was to kidnap you and hold you in Hollister’s basement until we could arrange to transport you here,” Welch said. “We reasoned that if anyone noticed that you had disappeared, the investigation would get no farther than the door of the mansion. Hollister would see to it that it was stopped at that point.”