Centigraphe Souverain The hand-wound movement measures elapsed times from one hundredth of a second to 10 minutes on three dials. The flyingseconds dial at 10 o?clock goes around in one second on a scale marked in hundredths of a second, making it theoretically possible to time an object moving at 360,000 km/h, or approximately 1/3000ths of the speed of light. One ingenious feature of the flying-seconds hand is that it can be stopped anywhere along its one-second journey around its dial, even between two 100th-second divisions, enabling an approximate fractional reading. On the dial at 2 o?clock, the hand revolves in 20 seconds around a time scale divided into seconds. The outer tachometer scale shows the speed against the odd seconds, while the inner scale corresponds to the even seconds. The third dial, at 6 o?clock, whose hand revolves in 10 minutes, has a similar tachometer scale with speeds corresponding to 20-second markers. The chronograph is started, stopped and zeroed by a rocker at 2 o?clock in the case band instead of the usual buttons on either side of the crown. This ergonomic solution has been patented. A second patent was granted for the ingenious configuration of the mechanism, which effectively isolates the chronograph from the timekeeping function. As a result, the amplitude of the balance is unaffected when the chronograph is running.