I visited the Deutsche Museum yesterday, where one of best attractions is the Foucault pendulum a 30 kg weight at a 60 m rope (the original at the Panthéon was 67 meter long and weights 28 kg). We could see, that the pendulum swings on a an elliptic course, hitting the conses always from the back. As we were told, the deviation of the pendulum is a function of latitude. The horizontal axis is the latitude from 90 degrees to 0 degrees latitude. The vertical axis shows the rate of precession in degrees per hour; positive for clockwise precession, negative for counterclockwise precession (the Coriolis effect seems to have a minor role). I wondered what might be the reason for the spin or chirality seen so often in nature. Most DNA has a right-hand screw (nevertheless there are hundreds of images on the net and many scientific papers) that show left-handed DNAs). Yea, yea.