The 14-ton 9ft-diameter bell in the clock tower of the Palace of Westminster (London), named after Sir Benjamin Hall (1802-67), commissioner of works when the clock was installed (1859). The sound of Big Ben striking the hour, first broadcast in 1923, has become a British national institution. Both the clock and the tower itself are also known by this name. A light in the lantern above the four clock faces indicates that the House of Commons is in session. The tower was substantially restored in 1985.