Big Ben clock turns 150 today

Three times a week, clock maker Paul Roberson climbs the 334 steps to the top of the Clock Tower in London to wind up and adjust arguably the worlds most famous timepiece.Commonly called Big Ben, which is actually the nickname of the bell inside it, the 96-meter tower looks down on the Houses of Parliament along the River Thames and has become a symbol of stability, endurance and democracy in Britain.It was 150 years ago on Sunday that the four-faced Great Clock started keeping time, and on July 11, 1859, Big Ben first struck time.The clock is 150 years old and still weight-driven so its weights that are driving the clock and those weights slowly work their way down to the ground, Roberson said.Roberson uses old pennies balanced on top of the pendulum to slow the clock down or speed it up, depending on whether it is running fast or slow.By adding a penny we can speed the clock up two fifths of a second a day, take the penny off and it slows it down, thats how we keep the clock spot on.