horologie
Christiaan Huygens van Zeelhem was a Dutch mechanic, physicist, mathematician, inventor and astronomer who formulated the wave theory of light.
An admirer of Descartes, Huygens preferred to conduct new experiments himself to observe and formulate laws. In physics, he contributed to the development of the crucial Huygens-Fresnel principle, which applies to wave propagation. He also extensively investigated free fall. He experimentally proved the law of conservation of momentum. He derived the law of centrifugal force for uniform circular motion.
He also invented the pendulum clock, discovered centrifugal force and the true shape of Saturn's rings as well as its moon Titan. Huygens is considered the first theoretical physicist to use formulas in physics and one of the founders of theoretical mechanics and probability theory.
