There were two incidents which led Galileo to move from being a physician to a mathematician. The first was in 1581 when Galileo first noticed that a chandelier despite swinging in large and small arcs took almost the same time to return to the first position. Amused by it, he set up two pendulums of equal length and swung them with a variation in sweep. Interestingly, both the pendulums, irrespective of their sweeps, took the same amount of time to return to the first position and synchronized with each other.