Sewing machine

Talking of the Docklands Light Railway, I have a sewing machine that I can't use because it's so frightening. I got it out once, and set it up (it's very old so you have to mess about with it for ages before it works), and then went to make myself a cup of tea. I was going back to it when I hear this mad, zinging, humming noise coming from the room; I was in alone, and my heart started racing. I stood outside the room for ages wondering if an intruder had got in somehow, until I realised that I had to go and investigate out of pure curiosity. The bloody thing had started sewing all by itself and was zipping along merrily as though an invisible seamstress was operating it. The only way I could stop it was to unplug it! I have not got it out of it's box since then, because I'm too terrified to use it.