"How could you tell?" Q asks dryly. "OOH!" he makes a sympathetic noise. "Can I get you anything?"
Q holds his breath as Severus writes, moving a bit so he can see.
"Or perhaps it's biding it's time," he comments, breathing out when nothing happens. "Or you and I aren't the ones it wished to speak to. Or we're not using the right language." He shrugs. "Or it's just a book, albeit a very old and valuable one." He runs a finger under the words Severus has written. "'...As in magic preservation in the pages of books.'"