The tourbillon has played an important role in the story of Speake-Marin. The first timepiece ever to bear the Speake-Marin name was the Foundation Watch, a hand-made pocket watch that Peter Speake-Marin equipped with a tourbillon escapement.
Peter Speake-Marin recognises the tourbillon’s capacity to improve timekeeping accuracy by averaging out positional errors due to gravity. However, it is the visual aspect of this mesmerising escapement that always draws him to it.
A tour of the dial side begins with the large oven-fired enamel subdial with the hours and minutes displayed by Speake-Marin's signature blued-steel Foundation hands. Just above the subdial is a 72-hour power reserve indicator displaying available power by means of a cam-shaped disc that opens when fully wound to reveal the gears and mechanisms below, and gradually closes and signals empty when a red section of the disc reaches the central marker.
However, it is the synchronised pirouettes of the twin tourbillons vertically aligned on the left that quickly attracts the viewer's gaze and grips it tightly. A single massive bridge, impeccably hand finished with mirror polished internal bevels, supports the upper side of both tourbillons. Each tourbillon has its own independent gear train powered by its own mainspring barrel. The two barrels are wound simultaneously via the crown. A miniature limited-slip spring gearbox – the spring absorbs and balances any subtle variations between the two cages – called an équilibreur de marche (rate equalizer) links the two tourbillon regulators.
The proportions of the generously sized 46 mm Piccadilly case, which is available in either white or red gold, have been deliberately considered, allowing both space for a large and legible time display as well as room for the tourbillons to be fully appreciated without being crammed closely together.
Inspiration for the movement bridge design and decoration of the Vertical Double Tourbillon comes in part from one of the first tourbillons in the Speake-Marin collection: The Vintage Tourbillon Mk II. Like the Vintage Tourbillon, the Vertical Double Tourbillon’s movement features German silver bridges, perlage and ruthenium plating. Geneva stripes covering the 3/4 plate movement differ from the status quo in that the waves run not in one direction but two, away from the centre of the plate.
The équilibreur de marche linking the two 60-second tourbillons consists of two concentric wheels arranged one on top of the other. A small spring sandwiched between the wheels has each end attached to a wheel. Each wheel rotates with its respective tourbillon cage and the spring between is tensioned when the rates of the two regulators differ, or if subjected to asymmetric shocks.