Phineas pushed himself clumsily to standing. “Harnessing is an advanced subject. Perhaps An Introduction to Harnessing by E.B. Sollentude, or The Wildspark Frequency Guide by Master Tinubu?”

“Yes, they sound good. But I was actually after some of the more specific areas too. For example, do you have anything on the theories of past lives of personifates, or … memory?”

Phineas scratched his head.

“It’s just that I would like to try to understand all aspects of the process, if I possibly can.”

“A noble pursuit, but I can’t say anything comes to mind on memory… Ha! I can’t remember books on memory! Get it?” Prue smiled and Phineas danced gawkily to a section and pulled several books from the shelf. “These are the two I mentioned, and this one by Master Hannah Woolstenbury herself may interest you. But I’m afraid you can’t take these from the library. You will have to read them here.”

“Thank you,” Prue said.

She sat at a table and opened the journal: First Harnessings: Trials and Tribulations by Hannah Woolstenbury. She skipped over the introduction and went straight to the diagrams of equipment. Most of them were for something called a spectral oscilloscope. It was fascinating reading, and she was thrilled to follow the calculations, but eventually they became so complex that she wished she had Agapantha to help her.

The door creaked open and Prue glanced up.

“Frances, I’m pleased to see you putting in extra time at the weekend,” said Craftsman Primrose. “Very diligent with all the work that’s to be done.”

“I thought I’d get ahead.” She hoped the half lie didn’t show on her face. But maybe she was getting good at lying.

“I’m rather partial to a bit of weekend study myself.”

“You must’ve read everything in these sections, Craftsman Primrose!” Phineas called from behind the pile of books he was sorting. “Lucky I’ve just taken a new delivery!”

Craftsman Primrose walked across to Prue. “What are you reading?”

She showed him the book.

“It’s certainly the most fascinating aspect of what we do here. The design and mechanics are crucial, of course, but the real magic is in the harnessing. Good to see you going straight for the tricky learning.”

As he moved to turn, Prue hesitantly said, “Sir, I have a question.”

“Yes?”

“I was just wondering if there might be a way to unlock memory in the ghosts.”

Craftsman Primrose frowned, then pulled out a chair and sat opposite. “Memory loss is a by-product of the process. It’s a curious thing, memory. Some say time leaves a trace in the frequency – all of our experiences stored in the very fabric of our imprint on the Universe.” His eyes narrowed thoughtfully behind his thin-rimmed spectacles. “I’ve often thought if only there was a way to pull out a particular part of the signal after a ghost was brought back, we might—”