Three tourbillons are in action, each rotating at different speeds to perform distinct gravitydefying functions. Two of them are nested one inside the other to rotate the fourth dimension of time through the three dimensions of space. In this bi-axial tourbillon, one tourbillon carriage rotates every 40 seconds within a second carriage going around in 120 seconds on an axis perpendicular to the first. This ensures that the vibrating balance moves through every possible plane in relation to the field of gravity to average out positional errors.
The third tourbillon carriage rotates a separate balance on a single axis in the conventional way, but at the relatively high speed of one revolution every 36 seconds. This tourbillon is most effective when the watch is in a vertical position, and by rotating the balance quickly it minimizes its exposure to the effects of gravity.
For even greater precision, the two regulating systems are connected through a differential gear that gives an average of their two rates. Uniting three tourbillions and two escapements with different properties in terms of mass, rotational velocity and inertia proved to be a delicate exercise in the balance of power. For example, the double tourbillon system has to be made as light as possible using titanium and aluminum alloys so that it does not consume a disproportionate amount of power at the expense of the single tourbillon.
The watchcase, engineered to display the tourbillon systems to their best advantage, is unlike any other. The complex architecture is constructed of 77 parts in white gold and non-reflecting sapphire crystals with the caseband and lugs in Zalium®, a hard and ultra-light zirconium alloy. The fluid outlines of the tourbillon housing in polished white gold contrast sharply with the rectangular rigidity of the lower case displaying the indications. The hours and minutes are shown on discs rotating against their respective markers, and the seconds on a scale around the bi-axial tourbillon. Harry Winston shows off its flair with gemstones by using sapphires and citrines to indicate the power reserve. Eleven color-graded blue sapphires from dark to pale show the power left in the mainspring. The markers for the hours and minutes are color-matched with the gemstones.