"'Since when?'
"'About an hour ago,' I said, airily. Out of the corner of my eye I saw that she had flushed up. It pleased me.
"'You will soon tire of the experiment,' she said, with a dangerous smile.
"'Oh, I may,' I replied, indifferently.
"She drew back. The movement was scarcely perceptible, but I noticed it, and she knew I did.
"The atmosphere was vaguely hostile. One feels such mental conditions and changes instantly. I picked up a chess-board, opened it, set up the pieces with elaborate care, and began to move, first the white, then the black. Miss Holroyd watched me coldly at first, but after a dozen moves she became interested and leaned a shade nearer. I moved a black pawn forward.
"'Why do you do that?' said Daisy.
"'Because,' said I, 'the white queen threatens the pawn.'
"'It was an aggressive move,' she insisted.
"'Purely defensive,' I said. 'If her white highness will let the pawn alone, the pawn will let the queen alone.'