"The matter we wanted to discuss…" said Blackbird.
"A moment only, I promise," interrupted Gregor. "This is impressive; wait and see."
An orange indicator turned to green and Gregor threw a switch with a flourish. A laser emitted a blue-white beam which was split by a half-silvered mirror and bounced around various prisms before hitting another pair of prisms which brought the beams together again into a single beam aimed at a detector. Gregor carefully adjusted an instrument that was receiving the beam.
The prisms and the mirror were inscribed with odd symbols — It made me wonder what his native language was. Something Eastern European by the sound of it.
"Watch the display," he said. "The red one shows total energy input while the blue one shows the energy released."
The lines on the graph started to climb until they levelled off about half-way up the screen, the red line on top indicating that energy input exceeded energy released by about a third again. A digital read-out measured the difference at just over minus twenty-seven percent.
"This is the default state. The gaps between the lines indicate the energy used by the system," he explained.
"Gregor, this isn't what we came to talk to you about," said Blackbird.
Gregor ignored her, intent on the rig. "Now," he said, "I'm using microwave transmitters to introduce harmonics into the beams."
He turned a dial and the blue line began to climb towards the red.
"That's just increasing the energy input to the system," I pointed out.
"It would be if the beams were absorbing energy from the microwaves," he argued, "but that's not what's happening. The energy in the microwaves is all accounted for in the measurements. There's no direct transference, or rather there is, but it's already been subtracted from the read-out."
The red line rose slowly as he increased the input, but the blue line rose faster, until it passed the red line and stabilised above it. The read-out said plus eleven point two percent.
"You must have an energy source that's not accounted for," I stated.
Blackbird kicked my ankle hard enough to get my attention. "What Niall meant to say is that we have a question we'd like your view on."
"No," he ignored Blackbird again. "It's all in the measurements. What's more, you can increase the input to the laser, and the percentage yield stays constant without increasing the microwave input." He adjusted the input to the laser and the blue line climbed even further away from the red one.
"That's not possible." I was sure I was right. "Energy has to come from somewhere."
"Niall. You're only encouraging him," said Blackbird.
"You're missing something, surely?" The experiment was interesting, but there had to be a source for the increased energy. It couldn't come from nowhere. It was a long time since I'd done any physics, but it was a basic law of the universe that you don't get something for nothing.
"That's what I thought," said Gregor, "but I'm damned if I can find it." He flipped the master switch and the system clicked off. The lines on the laptop dropped to nothing. "What was it you wanted to ask me?"
Blackbird glared at me, but I shrugged. He was clearly enthusiastic about his experiment. What harm could it do to let him demonstrate it?
"A couple of items were stolen recently," she explained, "and I thought you might be able to tell us what their significance might be."
"What sort of items?"
"A key from an Anglo-Saxon burial mound and a tail feather from a raven," I told him.
His eyebrows lifted. "Not the usual sort of thing," he stated. "What makes you think these thefts are related?"
"They were stolen at the same time," said Blackbird, "from the same place."
"The Tower of London?" said Gregor.
"How did you know that?" I asked.
"Give me another instance where ravens and keys are kept in the same place," he said. "I cannot think of one. Besides, your question answered mine."
"What do you think, Gregor? What are they doing with these things?" asked Blackbird.
"You haven't mentioned jewels, so I assume they didn't succeed in stealing those?"
"As far as we can tell," I said, "they didn't even try to steal them. They used the jewels as a distraction but then went for things that are worthless."
"They are only worthless to someone who does not value them," said Gregor.
"And you would?" asked Blackbird.
"Perhaps. A key and a feather are both potent symbols. A key is for opening, and as a symbol of secrets — things locked away. A feather is also a symbol. The Egyptians believed that the feather represented truth, and that in the afterlife their hearts would be weighed by their gods against a feather of Maat."
"Maat?" I asked.
"The essence of truth, usually represented by an ostrich feather."
"This was a the tail feather of a raven, not an ostrich," Blackbird pointed out.
"But the symbology may transfer," said Gregor. "Symbols are all about the power you invest in them. They could have taken a feather from an old hat, and it would still be a feather, but because there was nothing invested in it, it would have little power."
"So the fact that this feather was stolen from the Tower of London gives it power?"
"In a sense, yes, perhaps."
"So what is it for, Gregor? Why do they need a feather and a key?"
Gregor rubbed his chin, thoughtfully. "I do not know," he said finally. "I am not aware of any rituals that would use just those symbols. They are too ambiguous — too loose, do you see?"
"I'm not sure I do," said Blackbird.
"Most magic is the art of converting something you don't want into something you do," he explained.
"Like alchemy," I suggested, "transforming lead into gold."
"A simple matter. You sell the lead to someone who needs it and they give you money, which you turn into gold."
"That's cheating," I said.
"Is it? Or is it simply using a path which people who do not think do not see? Much of magic is like that — trading one thing for another."
"You make it sound ordinary," I said.
"True magic, though, is very much rarer. In true magic you extend the bounds of the universe to include the infinite, where limits become meaningless and therefore exchanging one thing for another becomes like getting something for nothing. You can appear to get more out than you put in, like my wave energy demonstrator. If I am right, it is drawing power from the universe itself, and therefore exhibits a resource which is, for our purposes, limitless."
"So is it science or magic?" I asked.
"A great question," said Gregor. "You must tell me when you have the answer. A feather and a key? They have no unifying symbology, no theme to draw upon. They do not in themselves define the boundaries of anything."
"You're saying they are insufficient in themselves?" said Blackbird.
"Indeed I am, Veronica. Much of logical deduction is not knowing the answers, but knowing the right question."
"What's the right question?" I asked her.
She grinned at Gregor. "What else have they taken?" "Correct," he said.
FIFTEEN
The market was near closing time. My visit to Gregor with Blackbird had delayed me and I had almost forgotten my invitation to meet Andy the honey-seller at the cafe. It was an outside chance that he'd appear, but having made the offer I felt honour-bound to at least turn up.
I sat in the cafe window, watching the market traders beginning to pack up their wares and close down their stalls. The idea of using someone to set up some sort of bridging arrangement with the fey courts appealed to me, but it needed someone the inmates would trust to front it. Andy had the potential, but I had to find him before I could pitch it to him. I'd been here for an hour, but there was no sign of him.