I loved this book all over again. I found that reading it with the internet close at hand was a boon, too. F'rinstance:

"The air rang with the energetic, joyful clamor of the birds. Only one, whose song came sweetly through the others, sounded meditative and solitary: three minor notes ascending...
'What's that bird, Jule? That sort of sad one?'
Julian listened. 'White-throated sparrow,' he told her."

And I found that it does sound exactly as described:
White-throated Sparrow.

There is also this, which I would like to have painted on the wall of my library:

"Sometimes a story can open a world for you: you step into it and forget the real one you live in."

That's how these books are.