“If. You know, Fowler, these people have the devil of a way of seeming plausible. You say he was right a lot, but I’ve seen mediums at work, and it’s amazing how the memory turns a few banalities, a lucky guess, and a bit of observation into miracle-working.”

“That’s undeniable. What we really need is a blind test,” Aaron said. “Make sure there are no clues for him to seize on at all and see what he comes up with.”

“How would you do that?”

Aaron had thought about this, possibly rather too much. “Give him writing from a lot of suspects in a case, and some from unrelated people too,” he said promptly. “Get him to say who he thought was guilty. But the thing is, we’d make it an unsolved case, one that was ongoing, with the man who gave them to him not involved in any way.”

“So he couldn’t read your face for the answer, or even suspicions,” Hollis said thoughtfully.

“Exactly. And mark the papers with numbers and somebody else has the key. So even if he found out what case it was, he still wouldn’t know who had written which paper. Get him to write his opinions down, so there’s no misremembering what he said. And lock his answers in a drawer, unread, until a culprit’s been identified, so there’s no possibility of his views influencing the investigation.”

“Yes, that would give you a very good idea of the value of graphology. A medium can fall back on The spirits aren’t talking to me or Someone at the seance is ruining the atmosphere or A ghost played a prank or suchlike, whereas with a Scientific Graphologist, surely he should be right or wrong, no excuses.” Hollis nodded slowly. “You’d need the right case, but I’d be very interested to see how that went.”

“So would I. I’ve been chewing over how the blighter does it for weeks. It would be good to confirm for sure he’s a fraud.”

“And handy if he turns out to be a genius. I wonder if he’d agree to the test?”

Aaron thought about Joel Wildsmith, who grew that moustache on purpose. “I think he might, if it was a challenge. If he didn’t, that would be telling in itself. Do you know, I’d blasted well give it a try, if I could find the right set-up.”

Hollis took a ruminative sip of beer. “If he failed, that would be pretty good evidence of making money by false pretences for the future, wouldn’t it? I might be able to help you with a case. Let me have a think.”

***