A relatively easy way to measure compass variation is to aim the north arrow of the compass card at the North Star Polaris and determine how far the magnetic needle points away from that line.
(A relatively easy way to measure compass variation; is; to aim the north arrow of the compass card at the North Star Polaris and determine how far the magnetic needle points away from that line)
A relatively easy way to measure compass variation
is
to aim the north arrow of the compass card at the North Star Polaris and determine how far the magnetic needle points away from that line