"Nope," said Margery.

"Bother, she's forgotten her music."

"What did you say, uncle dear; what did you say?"

I sighed and began.

"Once upon a time there was a balloon, a dear little toy balloon, and—and——"

"What's 'at?" asked Margery, making a dab at my chest. "What's 'at, uncle dear?"

"That," I said, "is a button. More particularly a red waistcoat button. More particularly still, my top red waistcoat button."

"What's 'at?" she asked, going down one.

"That is a button. Description: second red waistcoat. Parents living: both. Infectious diseases: scarlet fever slightly once."

"What's 'at?"