Definition
Charts are drawn in degrees true, so bearings taken with a hand bearing compass must have deviation and variation applied before plotting. Working from compass to true the corrections are added algebraically with east positive and west negative, summarised as compass to true add east. A bearing of 045 compass with 3 degrees east deviation and 2 degrees west variation gives 046 true. The reciprocal, obtained by adding or subtracting 180 degrees, is what is actually laid off from the object.
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