1. Adjusting heeling error at sea
Adjust for main causes of heeling error
( R, k rod and g rod)
If compass north is attracted to high side raise the heeling magnet if red end is of ship when rolling, up and lower the heeling magnet if blue end is up.
If compass north is attracted to low side of ship when rolling, lower the heeling magnet if red end is up and raise the heeling magnet if blue end is up.
NOTE: Any change in placement of the heeling magnet will affect the Athwartship deviations on all headings
(show with the diagram)

2. Adjusting heeling error at sea
The heeling effects of both the permanent and induced magnetism are corrected by adjusting the position of the vertical permanent heeling magnet. This adjustment can be made in either of two ways: Method 1. With the ship on an even keel and as close to the east or west magnetic heading as possible, adjust the heeling magnet until a dip needle inserted in the compass position is balanced at some predetermined position. Method 2. (This is usual at sea) Adjust the heeling magnet, while the ship is rolling on north and south headings, until the oscillations of the compass card have been reduced to an average minimum.

3. Adjusting heeling error at sea
Readjust the heeling magnet when the ship changes magnetic latitude appreciably because the heeling magnet corrects for induced as well as permanent magnetic effects. Moving the heeling magnet with Flinders bar in the holder will change the induction effects in the Flinders bar and consequently change the compass deviations. Thus, the navigator is responsible for: Moving the heeling magnet up or down (invert when necessary) as the ship changes magnetic latitude, to maintain a good heeling adjustment for all latitudes