After a two month hiatus, my walk continues. I am travelling above London Undergrounds Circle Line and aim to veer no more than a couple of hundred yards from the line itself. The walk is recorded with a primitive pinhole camera. Little more than a wooden box with a tiny pinprick sized hole to let in light, a pinhole camera is as basic as photography gets. Prone to error and open to guesswork it has no lens, no viewfinder, no light meter, complicated shutter, or electronics of any sort. A few pieces of wood and brass are glued together and everything else is up to imagination and luck. The Tube is much like that too, Victorian engineering that owes more than a hundred years of success to imagination and a bit of luck. Its passengers are often another story. Shutting out the world with iPods, newspapers and talk of the weather, Ive always imagined that they are largely oblivious to what the world looks like just ten feet above them. So, this walk. A mix of psychogeography, photography, history, and self education.