With the invention of the pendulum clock in 1656, Christiaan Huygens increased the best accuracy of clocks from 15 minutes deviation a day to around 15 seconds a day.

Black History Fact: Benjamin Banneker (1731–1806) was a self-taught mathematician and surveyor. When he was 21, Banneker was shown a pocket watch. He was so fascinated by the watch that its owner lent it to Banneker. He spent time studying pocket watches before deciding to build his own timepiece. A year later, Banneker invented a clock out of wood that struck a gong on the hour and kept time to the second. Banneker’s wooden clock kept time for more than 40 years.