This is a lovely octagonal Gents slave clock from 1947, with a 12 inch diameter dial. The case's overall size is eighteen inches and is made from Bakelite polished to a deep oxblood red. (Oxblood was actually used as a colouring agent in a lot of Bakelite products - hence the name.)
It was used by the GPO in telephone exchanges (Clock 4A), and would have been run from a PO36 Hipp toggle master clock like the one here.
The actual slave mechanism is identical to the one on the page explaining their operation Link.

The motto "Tempus Edax Rurum" (Time, the devourer of all things) is not original, as there would have been the royal cipher of King George there with the letters 'GPO' underneath like this :-



Another example of a 30 second pulse slave clock, this one being beautifully made from mahogany. The eight individual pieces of wood all being wedged and glued together. Workmanship like this would never be found today in such a utilitarian piece as an everyday clock.

The dial is not original to this clock, but instead features a 7 inch Synchronome dial made by myself. This was done by printing on photographic paper a vector image drawn using 'Coral Draw 12'. The measurements and proportions all being taken from an actual Synchronome 7 inch dial shown below on the left.



Click for Full Size 2262 x 1068

The problem with reproducing any dial is that the original has usually faded or gone yellow with age. Fortunately a ring around the outslide of the old one gave an idea of the original true colour.