I went to the table.

"I think," I said, "I'll try and screw in off the red." (I did this once by accident and I've always wanted to do it again.) "Or perhaps," I corrected myself, as soon as the ball had left me, "I had better give a safety miss."

I did. My ball avoided the red and came swiftly back into the left-hand bottom pocket.

"That's three to you," I said without enthusiasm.

Celia seemed surprised.

"But I haven't begun yet," she said. "Well, I suppose you know the rules, but it seems funny. What would you like me to do?"

"Well, there isn't much on. You'd better just try and hit the red ball."

"Right." She leant over the table and took long and careful aim. I held my breath.... Still she aimed.... Then, keeping her chin on the cue, she slowly turned her head and looked up at me with a thoughtful expression.

"Oughtn't there to be three balls on the table?" she said, wrinkling her forehead.

"No," I answered shortly.