The falling timeball (see here), as a means of indicating the time to ships in the Firth of Forth and to the gunner on the ramparts of Edinburgh Castle, hit a snag. Edinburgh and its environs suffer dense sea mists known locally as the haar (think ‘Arr, Jim lad’, Robert Newton’s interpretation of LJS by RLS…or the much better take-off by Tony Hancock – and if you don’t know what I’m on about, I’m sure Google will come to the rescue). The haar obscures the Time Ball, rendering it useless both to ships at sea and to the one-o’clock gunner on the castle ramparts, who probably had trouble finding his gun in the mist anyway. New technology came to the rescue. A wire was strung from the observatory to the castle (the mind boggles at this) so that at precisely 1pm somebody in the observatory could throw a switch to actuate an electric bell in a box on the wall beside the gunner on the ramparts. Though the Time Ball could not be seen from ships, the bang could be heard.
These days the gunner tugs a lanyard. Back then he would have lit a fuse. Did the delays matter? Did someone calculate the time it would take for the electricity to reach the bell (a bit more than the speed of light, probably) and the time for the fuse to burn down and fire the gun? You bet they did. From small beginnings like this, men flew to the moon.