HISTORIC EXPERIMENT PROVES EARTH'S ROTATION
The famous experiment which proves that the "earth do move" by letting the observer actually see it twisting underneath his feet, an experiment invented by the French mathematician Jean B. L. Foucault nearly a century ago was repeated recently under unusually impressive circumstances before an international scientific congress at Florence, Italy, the same city where Galileo once was persecuted for holding the same opinion.
From the center of the dome of the Church of Santa Maria di Fiore, Father Guido Alfani, director of the Astronomical Observatory, suspended a 200-pound weight on a wire 150 feet long. On the bottom of this weight was a tiny projecting point which traced a line on a table-top sprinkled with sand, as the great pendulum swung slowly back and forth. At a given signal Father Alfani set the pendulum to swinging. While the assembled scientists watched it, slowly the line traced across the sand table-top changed direction.
As Foucault proved long ago and as the watching scientists well knew, the table was being twisted underneath the pendulum by the rotation of the earth.