Clocks, Quartz Essen ring, 1938

Clocks, Quartz Essen ring, 1938. Essen ring, 1938. By cutting crystals of quartz in different ways, they can be made to vibrate at almost any frequency. In 1927, Warren Marrison produced the first clock to work by counting the vibrations of a piece of quartz. Louis Essen achieved greater precision by using rings of quartz instead of slabs. He found that variations in the frequency depended largely on the way in which the quartz was held in place. The Essen ring was a ring of quartz suspended by six silk threads. Clocks containing an Essen ring were accurate to one second in three years. ©SSPL/Science Museum