As I was working I noticed that the way I designed the differential gearing actually created a spare drive that sat directly below the emperor's feet, or where they would be if he were to sit in the chariot.

In the fairy tale the painting represents the here and now. The book is actually divided into five sections, through which the key character, the muse, leads us.

He was so tenacious he defied the distraction of women by refusing to have them in his presence, just as later in life he denied his blindness by calling for more and more candles.

It inspired all sorts of whims and fancies that I ultimately wove into a fairy tale complete with muse, the earth, the moon, some famous inventors, a dog and a rabbit.

I think most artists find it difficult to part with their work but it's the parting that keeps us alive and keeps us working. In the case of the chariot, although it's been sold I actually still have it, just in another form.

The original item looked like a little hand cart with the figure of a man mounted on a platform between the wheels. The man's outstretched arm always pointed south.

If you look closely you can see that they are all interconnected, symbolic of a never-ending circle in which it is simply impossible for the dog to catch the rabbit.