What nationality was the author of the book Horologium Oscillatorium?
Horologium Oscillatorium: Horologium Oscillatorium: sive de motu pendulorum ad horologia aptato demonstrationes geometricae (Latin for "The Pendulum Clock: or geometrical demonstrations concerning the motion of pendula as applied to clocks"), often abbreviated Horologium Oscillatorium, is a book published by Christiaan Huygens in 1673; it is his major work on pendulums and horology.
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