The third book – and if somebody had a bet with me 10 years ago that this would be the title of my third book, I’d have lost some money – was Faith in Conservation. It has plenty of fantastic illustrations, many from the Getty itself. When it was published I went up to give a special talk to the class that inspired me. They sent 20 questions and I answered most of them, and when they sent a thank you they suggested I write a book about paints for children.

I worked out the structure after primary school students in Yorkshire wrote to me asking about the history of colours. It was intended as a book for teenagers, but also for adults. It was published by the Getty Museum in Los Angeles and writing it included the extraordinary privilege of living in Getty scholars accommodation for five weeks and going every day up the hill to the museum and its amazing attached library the Getty Research Institute. My fourth book A Brilliant History of Color in Art came out in November 2014. I was told as I ran that other visitors had left early to make space for an unscheduled royal visit, but that I’d looked so settled and intense in my reading about fabrics that they’d let me alone, and just asked somebody to mind me until I was done, and then let me out of a secret gate. I read rapidly for the last hour until the end of the day, but then I was sneaked out, running through various back corridors in the labyrinth of public and private royal buildings, and through a tiny door and out into a rainstorm. Oh, and Thailand, where I was visiting the library in Bangkok’s wonderful Queen Sirikit Museum of Textiles in the King’s Palace when suddenly everything went quiet and I realised I was the only reader there. I haven’t yet worked out how many countries I visited, but it includes Papua New Guinea, France, India, China, Scotland, Guatemala, the USA, Norway, Italy and Spain. By the end I was slightly exhausted but really happy.

It took more than five years to write and finish. My fifth book, Fabric, was published by Profile Books in hardback in November 2021, and in paperback a year later.

Colour travels through the paintbox