You dope!

An isomagnetic map shows lines of constant magnetic field intensity. You
need the gradient map which shows the gradient of the isomagnetic
potentials. You want the lines that go to the north pole right? Not those
closed circles! Please, please tell me you never leave the dock. You are a
hazard to sailors everywhere!

Lloyd Bonafide


"Joe" wrote in message
ups.com...
To check a compass card and compare variation values maybe.

Joe