Here's the story. I was paying a lightning trip to Milan just after New Year and was trying to get a picture of a tram. So I braced the compact against a lamppost and waited. But a police car came for a closer look at what I was doing and I fumbled the shutter. So the police car left a red light trail across the shot, which was pleasing enough. The rule in this kind of shot is that movement can be blurred, but not anything else - like the buildings. Lots of symbols here - lights, crossings, junctions and three forms of transport. Red stands out because it is the colour of fire and blood and as a symbol it has considerable power. External lights on a car, boat or plane signify danger. They are the warning of an object ahead and akin to the traffic lights, port lights or a red sign barring the road. In the poem "Sir Patrick Spens", the Captain Spens is called to captain the King's ship. "The king sat in Dunfermline town/ Drinking of the blood red wine/ "Where can I get a good sea captain/To sail this mighty ship of mine?" Spens takes the job, but alas a mermaid appears and the ship is sunk. Thus the drinking of the blood red wine foreshadowed the tragedy. It was a warning and so Spens was always doomed. When blood red is hidden, it suggests life but when exposed, it means entirely the opposite.