Westclox 18" washboard wall clock with roman numerals is a beautifully made rustic clock! The large roman numerals allow the dial to be easily read from anywhere in the room. This clock requires 1 aa battery, not included. Add this clock to your home decor today! A clock or a timepiece is a device used to measure and indicate time. The clock is one of the oldest human inventions, meeting the need to measure intervals of time shorter than the natural units: the day, the lunar month and the year. Devices operating on several physical processes have been used over the millennia.