Longines Lindbergh Angle Horaire Mode D'emploi page 10

Using your Lindbergh Hour Angle Watch (See example b)
You have synchronised your watch with the radio time signal. We
assume that the time of your observation is 4:37 and 12 seconds and
that the equation of time for the day is minus 4 minutes and 50 seconds.
You move the stud «15» on the bezel to the left by four units. The units,
representing minutes, are conveniently etched into the side of the case.
Your readings:
seconds hand: centre dial
minute hand: bezel
hour hand: main dial
Because you moved the bezel by only four minutes,
we still have to account for 50 seconds (remember,
the equation of time for the day is minus 4 minutes
and 50 seconds).
On the small inner dial, 50 is opposite 12
Greenwich hour angle of the sun (your longitude)
18
3'
10˚ 15'
60˚
1 / : 12 1 / '
2 2
70˚ 30 1 / '
2
Important: If your watch stops it should only be repaired by an
approved Longines agent.
Precautions concerning the water-resistant seal
Your Longines watch is water-resistant but the seal may be damaged
without your realising it if the watch is subjected to a shock. The water-
resistant seal should be checked each time the watch undergoes its
regular service.
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