Margaret Cavendish was one of the people who came up in the course. That was when I started thinking about her as a character for a book, but my idea was for a totally different book. It had all these characters in it; Samuel Pepys was one of the main characters. He famously wrote these extensive diaries through the period that are really funny and sort of saucy, actually.

But when I realized it was actually going to be this portrait of the artist, birth to death, I had to then discover who Margaret as a young woman would be. I had to find the different voices for her throughout her life. I had a lot of fun discovering that. I had a lot of fun writing the childhood sections. By imagining her childhood, I was able to come up with this voice that matures as she gets older.

The way I've talked about my research process is that it was like magpies. I was just sort of moving through all these books and when something shiny would pop out I'd be like, Ooh, I love it! and I'd pluck it out. It's fun to figure out how to use those bits you really love - like I'd read about gold shoes with cork heels. Obviously, Margaret would have to wear those shoes.

I was sad to see some of them go. Like a magic lantern that would project images on walls and people would travel the countryside with these magic lanterns and tell stories. And there was this cabinet that you would walk up to and it had a little peephole and inside the whole thing was covered in thousands of little mirrors.

I loved reading historical novels when I was young, but I definitely don't think I wrote one. When I read my book through, when it was completely done and in printed galleys, I was surprised by how uninterested in the passage of time and history the book seemed to be. Even though you can feel it all there, that's just not what it's focused on.

I was obsessed with the scientific instruments people were building and all the weird experiments they were doing. I did actually wind up working in some of that, but there were whole sections I'd written about these instruments that ultimately had to be abandoned when I realized that the book really was about Margaret Cavendish. I couldn't justify using all of them.

I had all these sparkles I'd collected and wanted to work in, but when I originally started writing it and it was originally this novel about all these people set in 1666, what I was so interested in was the New Science.