"We don't have machines that add or subtract - at least, I assume you're talking about something more autonomous than an abacus."

Huh. He would have thought the Magical Flying Islet Society would have calculation magic.

He's going to wait a few moments for Command to say something if they think he shouldn't explain. Command says it's fine.

"I can demonstrate." He takes out a similar model e-reader to the one the pilot had. It's also only black and white. Functionally it's actually closer to a smartphone, though the display is e-ink and it's a lot wider and taller than Earth ones. This one is touchscreen.

He puts it to a calculator app and writes with the stylus. It has OCR, so the handwritten numbers are interpreted by the computer. He reads out as he writes.

"One gross five dozen to the power of two divided by eight times three equals... nine great gross four dozen and six."

"I understand the theory of how it works, though I don't know how to create one or how it works in practice, except for the very simplest mechanical models."

"I can begin to think how I might make a machine that adds and subtracts by moving objects around somehow. I cannot begin to think how I might make a machine that recognizes handwriting," she says, staring in fascination at the e-ink display. "—also we use numbers differently, ours go by tens, but I think I can calculate the translations in my head."