Normally Harry would have laughed at such things along with the Professor. But his throat felt tight and dry for some reason. 'Er... I suppose so, professor,' he answered nervously.
Professor Teo turned to look out of the window, a habit of his. Harry knew that this was his moment to try out the whistle. While the professor wasn't looking, he took out the whistle and blew it. Then all became still. All became silent. Harry clapped his hands in front of the professor, shouted at him and waved his hands in front of his face. Professor Teo did nothing. He was like a figure made of stone. Exactly as expected. Harry then waited for exactly five minutes — he counted the seconds himself - before blowing the whistle again. The world of sound and movement returned and the professor turned towards him. 'Is everything all right, professor?' asked Harry. 'Of course, Harry. You know I don't believe any of that kind of rubbish. I'm fine,' the professor told him. 'No,' said Harry. 'I mean, you didn't hear anything just then, did you?' 'Only the birds and the traffic, Harry,' said Professor Teo. 'Was I meant to?' 'No, of course not,' said Harry. 'It must have been my ears making funny sounds. I have a bit of a cold and it gets to my ears as well. Sorry.' 'Well, if you are unwell you must rest, Harry. Take care,' said the professor as he left the room. Harry quickly went to the telephone to call the speaking clock. When he put the telephone down he knew. No time had passed while the professor had been still. No time - anywhere. The five minutes he had counted had never happened to anybody but himself. When he blew the whistle he must have been outside time in some way. So the whistle didn't actually stop movement or sound. It stopped Time itself