“I shudder to think what your benighted sister would do with it. Explode something, obviously, but what?” He stood up, piling the plates and clearing the bags. “Don’t work yourself into a state of nervous exhaustion, and if you can spare five minutes to finalize that streetlamp proposal, I’m sure the citizens of Montreal would be most grateful.”

“Mmm,” Sam said, biting into a cookie. “That’s due the sixth?”

“The twenty-ninth.”

“I’ll make time. Night.”

“Night.”

Sam sat at the table a bit longer, yawning and turning over his next course of action in his mind. The ghost was determined not to come out and play, and he’d exhausted every trick he could think of to convince her … it … they to do so. With another yawn he turned to the designs for Montreal. He’d knock them out quickly, so he could go back to thinking about her. One of the hers, at least.

Right as he was calculating the number of streetlamps he was promising, it happened. He’d counted the number they’d proposed in the downtown area, fifty-four, and the ones a little farther up in one of the residential neighborhoods, twenty-seven, and added them together to get the total.

And made six.

He didn’t even catch the error until he’d written it down on the form Henry had given him: Downtown: 54 lamps. Residential: 27 lamps. Total lamps: 6.

For a minute he wondered if he’d finally gone mad. Carefully he brought the two numbers together again and got eighty-one. The world righted itself enough to allow him to take a deep breath, and he sat very, very still and thought.

Samuel Moore did not make adding mistakes. Ever. He could not remember a time, not once in his entire life, when he had made any sort of mistake in either addition or subtraction. The numbers were simply there, whenever he called upon them. It was like looking at blue and thinking it was red.

And besides, surely this wasn’t the sort of adding mistake people made? Eighty-one wasn’t even close to six, except perhaps in a very relative sense.…

Six.

Six rolls instead of three. The sixth instead of the twenty-ninth. Six instead of eighty-one.

A pattern ending in five, where the answer was a six …

“I’m sorry,” he said quietly. “You must think I’m very stupid. Here you’ve been trying to get my attention and I haven’t even noticed.”

No one answered him, but he hadn’t expected anyone to.

“Are you letting me know you’re here? In case I wasn’t sure? That was very thoughtful of you. I’m sure now.” Excitement was crawling along his skin, his heart beating faster and faster in his chest. “My god, you can get into my head. You can influence my thoughts. How far, I wonder? Could you tell me to do something, or is it limited to sixes?”