"You need to hold the pot to see how it works.........Here hold that."

"I'm afraid to drop it."

"Nonsense.  You've got good hands.  Remember?"

Dorothy stood with the pot in her hands, which held the cool light weight of the shell.  The moment it was between her fingers she felt it three-dimensional.  It was a completely different thing if you measured it with your skin instead of your eyes.  Its weight - and the empty air inside it - were part of it.

A.S. Byatt The Children's Book