“Ah.” When he smiled he looked like a mischievous imp. “Then we use the verbal clues. We’ve a whole long list of them. Let me show you. Bess, I’m standing next to a lovely lady here, so pray tell what object she is holding in her hand?”

“A purse,” Bess said quickly.

I looked at them, perplexed. “I’m afraid I don’t understand.”

“Again we have a great long system of code words. If I use the word ‘pray’ I am referring to ‘purse.’ If I use ‘please’ it’s ‘handkerchief.’ ‘Say’ means ‘money,’ and so on. We’ve about twenty items that usually come up at these performances. If it’s something unusual—and sometimes they try to trick us—then those same words will be used as letters, to spell out the word or enough of the word for Bess to guess. Supposing someone gave me a child’s toy soldier. “I’d say ‘Pray be quick,’ and I’ve spelled out ‘T O Y.’ ”

“Then I’d say, ‘I’m getting the feeling that it’s some kind of toy. . . .’ and wait for more clues, and Harry would then spell enough of soldier until I get it.” Bess nodded at me encouragingly. “But we rarely get something difficult. It’s usually watches, jewelry, handkerchiefs, smelling salts—”

“What is the word for smelling salts?” I asked, intrigued now.

“Speak,” Houdini said. “So I’d say, ‘Speak up, my dear.’ ”

“I see.” I nodded. “That’s really clever.”

“I hope you really are a fast learner,” he said, “because I’ve a lot to teach you and not much time.”

“I’m ready to start now if you are,” I said. I opened my purse and took out my notebook.

Harry shook his head. “Oh, no. You’re going to have to keep it all in your head. I’m not having my signals leaving this house. I keep the diagrams for all my illusions under lock and key all the time.”

“They live in a suitcase under the bed,” Bess chimed in and got a frown from Houdini.

“Do you think that was what someone was trying to steal?” I asked. “Bess said that someone tried to break into your house one night, then ran away when you got up and turned on the light.”

He frowned, shot her a quick look of annoyance, then shook his head. “Bess gets nervous at night if she hears the slightest noise. If he was trying to break in, then he was a regular burglar, and obviously I scared him off.”

As he said it I picked up a strange undercurrent and got the feeling that there was something that he hadn’t told his wife. Again my thoughts went to gangs and protection money. Somehow I would have to persuade Daniel to have his men find out more for me, because for once I agreed with Daniel. This was not something I wanted to investigate myself.