Old Mrs Harris goes to the doctor with an embarrassing problem. ‘I pass wind all the time,’ she says. ‘It doesn’t smell, and it’s completely silent, but it’s very uncomfortable. In fact, I’ve done it 20 times since coming in.’ The quack thinks for a minute then gives her a prescription. ‘Try taking these pills for a week and come back and see me then,’ he tells her. The next week, an even more embarrassed Mrs Harris marches in. ‘Doctor, I don’t know what was in the pills, but my problem is worse! My wind is as bad as ever, but now it stinks too!’ ‘Calm down,’ says the doc. ‘Now we’ve sorted out your sinuses, we’ll see to your hearing …’