Across the ship from side to side or, in other words perpendicular to the centerline of the vessel.

The compass part imprinted with the heading graduations, commonly referred to as the dial.

An assembly of two brass or aluminum rods with magnets that can be rotated to create a magnetic field, equal in strength but opposite in polarity to the boat’s disturbing magnetic field, thereby elimi [..]

N 000°, S 180°, E 090° and W 270°

Determining the position of a vessel by adding to last fix the vessel’s surface course and speed for a given time.

The angle between the compass heading and the corresponding magnetic direction.  The differences caused by magnetic influences onboard the boat, and the change in the boat’s heading.

  A device with a compass-like card and rotatable pointing and sighting vanes used to take bearings.

The process of placing a vessel on various headings and comparing magnetic compass readings with the corresponding magnetic directions to determine deviation.