He sat there on the rough form with his slate before him, hearing half-unconsciously the shouts, laughter, and ring of feet coming up from the darkness outside, and the faint notes of a piano, which filtered through the double doors from one of the rooms, where a boy was practising Haydn's "Surprise," from Hamilton's exercise book, a surprise which he rendered as a mildly interjectional form of astonishment. All the time Paul was racked with an intense burning desire to get up and run for it then, before it became too late; but cold fits of doubt and fear preserved him from such lunacy--he would wait, his chance might come before long. His patience was rewarded; the Doctor came in, looking at his watch, and said, "I think these boys have had enough of it, Mr. Tinkler, eh? You can send them out now till tea-time." Mr. Tinkler, who had been entangling himself frightfully in intricate calculations upon the blackboard, without making a single convert, was only too glad to take advantage of the suggestion, and Paul followed the rest into the playground with a sense of relief. The usual "chevy" was going on there, with more spirit than usual, perhaps, because the darkness allowed of practical jokes and surprises, and offered great facilities for paying off old grudges with secrecy and despatch, and as the Doctor had come to the door of the greenhouse, and was looking on, the players exerted themselves still more, till the "prison" to which most of one side had been consigned by being run down and touched by their fleeter enemies was filled with a long line of captives holding hands and calling out to be released. Paul, who had run out vaguely from his base, was promptly pursued and made prisoner by an unnecessarily vigorous thump in the back, after which he took his place at the bottom of the line of imprisoned ones. But the enemy's spirit began to slacken; one after another of the players still left to the opposite side succeeded in outrunning pursuit and touching the foremost prisoner for the time being, so as to set him free by the rules of the game. The Doctor went in again, and the enemy relapsed as usual into total indifference, so that Paul, without exactly knowing how, soon found himself the only one left in gaol, unnoticed and apparently forgotten. He could not see anything through the darkness, but he heard the voices of the boys disputing at the other side of the playground; he looked round; at his right was the indistinct form of a large laurel bush, behind that he knew was the playground gate. Could it be that his chance had come at last? He slipped behind the laurel and waited, holding his breath; the dispute still went on; no one seemed to have noticed him, probably the darkness prevented all chance of that; he went on tip-toe to the gate--it was not locked. He opened it very carefully a little way; it was forbearing enough not to creak, and the next moment he was outside, free to go where he would!