Back when I was an engineer working on construction sites, I always hoped that we would come across an exciting archaeological find when the foundations were being dug – Roman remains, perhaps, or a buried stash of gold coins. Disastrous for the project programme, I know, but it would have been fun. Anyway, today I had my own little archaeological dig; not so much Roman remains, as London Transport’s. Digging holes for rose bushes in a garden that backs onto the London Overground line, every time the spade went in, it hit something that wasn’t earth. Bricks, lumps of concrete, old rusted track bolts, you name it, we dug it up. Sadly though, despite much sweat, muttering and backache, no gold coins. Maybe next time…