A lot of what I write comes from tiny fragments of experience - some of it I look out for, some of it catches my attention - and now it comes looking for me.
There's a noise in Hidden Daughter, called singing. Novice time-traveller Greg Pope hears it as the Needle powers down after it is used to pull him back from the execution of Charles the First - it's strange, and metallic, and unnerving, like the rattle you hear from under your car as you're half way past the car you're overtaking. The original singing noise in my head as I began to write Hidden Daughter came from a memory of hearing trees scrape against metal fencing one day; then a few months later, I found this on the BBC news website: a different, but the same, strange anti-melodic patterns.
Then on Sunday, I'm in the park watching the local cricket team move the big panels they use to stop the balls going too far from the crease. The wheels hadn't been oiled since goodness knows when - and the squeak all four wheels made at once...
It's a bit of an unnerving experience when these things seem to seek you out, but an exciting one; I hope readers of the Hidden Daughter feel the same way when they hear the singing as they read.