Edinburgh's iconic time ball on Calton Hill to be removed under revamp

Edinburgh’s iconic time ball – installed over 170 years ago to help ships set their clocks – was removed by crane yesterday as part of plans for a new automated system.

The time ball, on top of the Nelson Monument on Calton Hill, was once vitally important to ships in the Port of Leith and anchored in the Firth of Forth, to help them adjust their clocks for navigation.

The 90kg ball, made from wood covered in zinc, was installed in 1853, and was dropped from the top of a mast at exactly one o’clock each day via an underground wire connected to the city's observatory.

In 1861, the One O'Clock Gun at Edinburgh Castle was introduced to provide an audible signal in case of fog obscuring the ball, but the tradition continued in sync.

A new mast will be built on the parapet of the 105ft-tall commemorative tower, while the time ball mechanism will be fully refurbished and a new automated system put in place.

The A-Listed monument, which has been closed since structural issues were identified in 2020, is set to reopen later this month following the work. It will close again in September for around three weeks for the installation of the new mast and time ball mechanism.

Councillor Val Walker, Edinburgh's culture and communities convener, said: "The main elements of the repair to date have been to the building itself. We’ve also been looking into replacing the mast on top of the monument and full refurbishment of the time ball, both of which have required working with specialist teams and a large capital investment.

"When reopened, the monument will operate for the summer months while a new mast is built and the time ball mechanism fully refurbished and a new automated system created. The monument will then close again around late September for the installation of the refurbished time ball and new mast."

Andrew Walls, project manager for Ashwood Scotland Ltd, the principal contractor employed by City of Edinburgh Council to remove the mast and time ball, said: "It's highly skilled work. The mast and the ball will be taken away, repaired, upgraded and replaced."

The Nelson Monument was constructed between 1807 and 1815 to commemorate Admiral Lord Horatio Nelson and victory at the Battle of Trafalgar in 1805. Designed in the shape of an upturned telescope by the architect Robert Burn, the monument is one of the most visible structures in the capital.

The time ball was added in 1853 by Charles Piazzi Smyth, the photographic pioneer and Astronomer Royal for Scotland, and was raised shortly before 1pm each day and lowered exactly on the hour. By 1861, the One O'Clock Gun at Edinburgh Castle was added to provide an audible signal.

The time ball was damaged by a storm in 2007, and repaired and brought back into service in 2009. In recent years the mechanism has been operated manually, based on the firing of the One O'Clock Gun, but the new work will introduce an automated system.