Isochronous The term isochronous describes something that is equal in duration or in frequency; in other words, occurring over the same amount of time. Galileo Galilei was the first to note the isochronicity of pendulum swingswing (technically known as the oscillation period) under certain conditions.[1] Around 1604, he conducted experiments on the swing of pendulums of equal length and concluded that regardless of the mass of the weight he suspended from the string, the period of the swing remained unchanged. The same phenomenon was observed when he set up two identical pendulums side by side and set them swinging, one with a small arc and the other with a large arc; they both swung back and forth with the same period. Through these experiments, Galileo confirmed the isochronous nature of the oscillation period of a pendulum under conditions of differing pendulum weight (mass) or length of swing. Galileo’s observations had a direct effect upon horological development, because the pendulum’s isochronicity makes it useful for regulating timekeepers. His experiments and observations greatly influenced the Dutch mathematician and scientist Christiaan Huygens, who would go on to construct the first truly isochronous pendulum in 1656, thereby inventing the first domestic clock. End Note [1] Wooten 2010, 81–82 Reference Wooten, D. 2010. Galileo: Watcher of the skies. New Haven and London: Yale University Press.
