1-158-435 - Oxford Science Archive/Heritage Images

Galileo observing the swaying of the chandelier in Pisa Cathedral, c1584 (1870). Galileo Galilei (1564-1642), Italian astronomer, mathematician and physicist, used this observation in his work which led to his discovery of the isochronism of the pendulum and eventually, through Huyghens, to the development of the pendulum clock. From Vies des Savants Illustres by Louis Figuier. (Paris, 1870).