Bob liked to sit in a meadow and throw bits of bread to the birds. He had done this once with a flock of some hundred pigeons who had, once they’d gotten the general idea, surrounded him and waited patiently for him to throw out each scrap. But presently a sparrow had come along and begun to collect evey last crumb that Bob tossed, even though it had been one against a hundred. Even if Bob lured the sparrow to one side, then threw the morsel to the other, the little bird would come across like a flash of light from a signal-mirror and wend its way among the stumbling pigeons and pluck the bread right out from under their open beaks, which would snap together on thin air.