How to Remove bubbles from magnetic compass ?

A bubble may form in the bowl owing to the fact that some of the liquid has somehow escaped from the bowl. This is a bare occurrence and must be remedied by following the manufacturer’s instructions. In most compasses:

1. Tilt the bowl until the “filter hole” comes upper most. This hole is provided on the side of the bowl.
2. Unscrew the stud/screw provide.
3. Top up with ethyl alcohol. If this is not available distilled water would be added.
4. Screw the stud/screw back into place.
5. Gently let the bowl return to upright.

In some modern compasses, small bubbles may be removed as follows;

1.  Invert the bowl gently. This would cause the bubble to enter a bubble trap provided for this purposes.
2. Gently return the bowl to upright.

          The bubble should have disappeared.