Bramwell Brown Tide Clock, Instruction Manual

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How your Tide Clock Works
As mentioned above, your Tide Clock works on a semi-diurnal
mechanism. This means that it works by timing the Moon’s
orbit around the Earth
(which takes 24 hours, 50 minutes and
30 seconds) , and therefore the gravitational force behind the
twice daily rise and fall of a standard semi- diurnal tide. This
tidal pattern is shown in the diagram below.
The circuit board inside the clock precisely measures the
average 6 hours, 12½ minutes between high and low tides
and instructs the motor when to turn and so move the sea level
in the display.
To fully enjoy your Tide Clock you need to appreciate that the
gravitational pull of the moon is not completely consistent over
the lunar month. As a result of this, there are slight fluctuations
in the time between daily high and low tides and, as mentioned
already, the 6 hours and 12½ minutes is an
average .
Each month, as the time between High Water and Low Water
deviates slightly away from that average 6 hours and 12½
minutes, the
T ide C lock’s accuracy will gradually reduce. Then
over the following days, as the time between High Water and
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