Monday, 17 May 1999
Even been in the London underground? The map of the London underground, click for enlargement Odds are good that you have been staring at the famous map (.../colourmap.gif) . It looks a bit complex at first sight. So many lines, in so many directions! How complex and fascinating.

The complexity is all right once inside the tube. It seems like the chosen line just goes straight. Every station offers a simple choice, disembark or remain seated. The entire complex diagram has been simplified to a sequence of simple yes/no decisions.

The other lines are almost completely out of sight. Occasionally an other line comes alongside and offers an opportunity to transfer. Flattend crossing of subway lines The confluence is usually short, one, two, a few stations at most. The paths separate shortly afterwards. Chances for a rebound are scarce. Most lines cross just once. So, it's essential to switch on time.

The simplification one straight line with a crossing once in a while does not hold long. Loop at Heathrow At Heathrow the Piccadilly Line (.../piccline.html) ends in a loop. Try to simplify that to a straight line and you'll run into yourself. What looks like two crossing is in reality the begin and end of one and the same loop.

When the passenger gets wind of the loop, it's too late. The tube has turned around unnoticed already. Stations repeat themselves in reverse sequence, with the left and right platforms swapped. All stations are already familiar. What started with fun and excitement now turns into a repeating, predictable, boring routine.. So, switch track on time, and not just in the subway.

Till next week!