Edinburgh Castle, Edinburgh · Travel Poster

Not just a view, the heritage behind it. Ella writes about the place, its hidden history, and the details that never make it into the guidebooks, all printed on the poster.

Everyone comes to Edinburgh Castle for the crown of Scotland and the boom of the gun at one o'clock, and almost nobody knows that the gun is really only there for the fog. The clock that actually mattered stood a mile to the east, on top of the Nelson Monument on Calton Hill, where from 1852 a great zinc covered ball was hauled up a mast every day and dropped at exactly one o'clock. It was the idea of Charles Piazzi Smyth, the Astronomer Royal for Scotland, and it was aimed not at tourists but at the ships anchored down in Leith and out in the Firth of Forth.

A captain who caught the precise moment of the fall could set his marine chronometer to it, and a chronometer set true was the only way to work out longitude and so find the shortest, safest road across the sea. The trouble was Edinburgh weather. On a 'haar bound' afternoon the ball simply vanished into the murk, so in 1861 the castle gun was added as a signal you could hear when you could not see, the two wired together across the city. Even then the sailors had to think, because sound crawls along at about three hundred and forty metres a second, so the bang took a full ten seconds to roll down to Leith and longer to reach a ship standing further out, and every navigator had to subtract that drift before he trusted his clock. The guidebooks tell you to cover your ears at one o'clock. They rarely tell you the gun is only the understudy, and that the whole performance was staged for men at sea setting their watches by a falling ball.

An original illustration, available in colour or black and white, created for the Ella's Adventures travel poster series.

No frame included.

Please note that, to protect the original artwork from copyright infringement, the images shown on this website are low resolution. The poster you receive is printed in high resolution, with all the detail and clarity of the original.