A very heavy marble column of length L to be used in the Parthenon in Athens in 440 B.C. was placed horizontally on two rocks that supported it at its ends, waiting to be used in the construction. A supervisor S, noting the empty space between the ends and worrying that the column might snap in two, asked the workers to place another rock somewhere near the middle of the column to better support it before it was to be used in the construction. Soon after the workers added the extra support, the column snapped in two. The site engineer E was able to explain what happened to Phidias, the architect. Needless to say, the supervisor S was fired on the spot, and the engineer became the new supervisor. Can you explain what happened, by eventually using a shear-force and bending moment diagram and the flexure formula?