I am an inter-tidal archaeologist and have worked on the Thames since 1993. One stretch that I have concentrated on is Bankside, a popular part of the foreshore, yet it’s never the same. You can go to the same geographic place, day after day, week after week, year after year, and it is never, ever the same. I used to teach primary school, before I had my six kids. And then I went into archaeology. My first term at University College London they were just beginning to look at the material from the Thames — everyone said you couldn’t use it because it had no provenance, it was all muddled. I went down to the Thames at Bermondsey and I was fascinated – this stuff was just sitting there. I call it beachcombing, which is very different from mudlarking really, which has an implication of digging, and unless you have a special permit you are not allowed to dig.