The magic is revealed when you look through the crystal case back. Here you’ll observe a clear separation: on top is the ‘traditional’ watchmaking movement and at the south is their unique technology with its fluidic module composed of two bellows (from NASA) and a capillary filled with liquids of different densities so that they do not mix (one colour, the other transparent).
The H1 featured a green liquid but subsequent collections have a variety of colours to choose from. A small piston on top of one of the bellows (the second is ‘passive’) is the interface between the watchmaking and the fluidic technology. The piston receives the energy from the watchmaking movement to compress the active bellow. When this happens, the coloured liquid is released into the capillary and presses the clear liquid back into its own bellow. Much like a pump system. When the coloured liquid reaches 6pm, all the liquid returns to its bellow in less than 60 seconds and the process starts all over again. Liquid time indicates hours, the mechanical dial indicates seconds.
Although it has an eight-day power reserve — gauged by the right eye in the skull — this is still a mechanical watch and the Audemar Piguet movement still needs your interaction to keep it wound. The pocket watch has no minute hand so time is estimated by what the company calls the “philosophical hours”.
The Skull Pocket is limited to eight pieces at CHF115000 (approx R1.5-million) each.