F.P. Journe

bs22fly
1535

• Show profile
• Show other posts

The indications

The flying-seconds hand at 10 o’clock goes around the dial in one second against 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.

On the dial at 2 o’clock, the hand goes around in 20 seconds and the time scale is marked in seconds. The
outer tachometer scale shows the speed against odd numbers of seconds — 1, 3, 5, etc. — while the inner
scale corresponds to the even numbers of seconds.

The third dial, at 6 o’clock, where the hand goes around in 10 minutes, has a similar tachometer scale with
speeds corresponding to 20-second markers. Thus a kilometre travelled in three minutes 40 seconds
represents a speed of 16.4 km/h (to one decimal place).