There it was, the size of a golf ball and as brilliant as the morning sun: a globe of light.

That’s when I found out why Nightingale insisted I keep a sink filled with water nearby while I did the exercise. Unlike his globe of light, mine was yellow and was giving off heat, loads of heat. I yelled as my palm burned, and stuck my hand in the sink. The globe sputtered and went out.

‘You burned your hand, didn’t you?’ said Nightingale. I hadn’t heard him come in.

I pulled my hand out of the water and had a look. There was a pinkish patch on my palm but it didn’t look that serious.

‘I did it,’ I said. I couldn’t believe it; I’d done real magic. It wasn’t some stage trick by Nightingale.

‘Do it again,’ he said.

This time I held my hand directly over the sink, formed the key in my mind and opened my hand.

Nothing happened.

‘Don’t think about the pain,’ said Nightingale. ‘Find the key, do it again.’

I looked for the key, felt the engine turn over and opened my hand to release the clutch.

It burned me again, but it definitely wasn’t as hot and my hand was much closer to the water. Still, I checked my palm – this time it was going to blister for sure.

‘And again,’ said Nightingale. ‘Reduce the heat, keep the light.’

I was surprised how easy I found it to obey. Key, power, release – more light, less heat. Warmth this time, not heat, and a yellow tone like an old 40-watt bulb.

Nightingale didn’t have to tell me again.

I opened my palm and produced a perfect globe of light.

‘Now hold it,’ said Nightingale.

It was like balancing a rake on your palm: the theory is simple but the practice lasts five seconds, tops. My beautiful globe popped like a soap bubble.

‘Good,’ said Nightingale. ‘I’m going to give you a word and I want you to say this word every time you do the spell. But it’s very important that the spell’s effect is consistent.’

‘Why’s that?’

‘I’ll explain why in a minute,’ said Nightingale. ‘The word is lux.’

I did the spell again: key, motor. I spoke the word on the release. The globe sustained for longer – it was definitely getting easier.

‘I want you to practise this spell,’ said Nightingale, ‘and just this spell for at least another week. You’ll have the urge to experiment, to make it brighter, to move it around …’

‘You can move it around?’

Nightingale sighed. ‘Not for the next week. You practise until the word becomes the spell and the spell becomes the word. So that to say “lux” is to make light.’

‘Lux?’ I said. ‘What language is that?’

Nightingale looked at me in surprise.