‘It’s this wretched chalk! I can feel it already! I can do magic on honest soil, and rock is always fine, and I’m not too bad on clay, even… but chalk’s neither one thing nor the other! I’m very sensitive to geology, you know.’

‘What are you trying to tell me?’ said the voice.

‘Chalk… is a hungry soil. I don’t really have much power on chalk.’

The owner of the voice, who was hidden, said: ‘Are you going to fall over?’

‘No, no! It’s just the magic that doesn’t work…’

Miss Tick did not look like a witch. Most witches don’t, at least the ones who wander from place to place. Looking like a witch can be dangerous when you walk among the uneducated. And for that reason she didn’t wear any occult jewellery, or have a glowing magical knife or a silver goblet with a pattern of skulls all round it, or carry a broomstick with sparks coming out of it, all of which are tiny hints that there may be a witch around. Her pockets never carried anything more magical than a few twigs, maybe a piece of string, a coin or two and, of course, a lucky charm.

Everyone in the country carried lucky charms, and Miss Tick had worked out that if you didn’t have one people would suspect that you were a witch. You had to be a bit cunning to be a witch.

Miss Tick did have a pointy hat, but it was a stealth hat and only pointed when she wanted it to.

The only thing in her bag that might have made anyone suspicious was a very small, grubby booklet entitled ‘An Introduction to Escapology’, by The Great Williamson. If one of the risks of your job is being thrown into a pond with your hands tied together, then the ability to swim thirty yards under water, fully clothed, plus the ability to lurk under the weeds breathing air through a hollow reed counts as nothing if you aren’t also amazingly good with knots.

‘You can’t do magic here?’ said the voice in the hat.