From Sundial to Atomic Clock: Evolution of Horologe
从日晷到原子钟：计时工具的演进

Different Horologes like sundial, machine clock, quartz clock and atomic clock are analyzed. Evolution of horologes based on from natural phenomena, mechanics, to high frequency vibration is elaborated. The escapement mechanism in Chinese chronometer, a transition between clocks based on the first and second principle, is discussed as a technical preparation for the invention of machine clock.