by Michael Hodgson

An Adventure Network surfer recently asked: "I have a compass I really like, but a small bubble has appeared in the housing and, to make matters worse, the needle sticks from time to time. Do I need a new compass?"

My advice is:

Over time, the needle on any compass may begin to act sluggishly, even appear to stick to the bottom of the liquid-filled housing—as you have indicated yours is doing. Most often, this is due to a build up of static electricity within the housing and can be corrected by simply rubbing a small amount of water directly over the housing to disburse the static charge.

It is not uncommon for a small bubble to appear in the liquid-filled housing when you are using your compass in high elevations or in temperatures below freezing. The bubble forms because the fluid within the housing contracts or expands at a faster rate than the housing, resulting in a "vacuum" bubble. This bubble will not affect the performance of your compass as the liquid's sole purpose is to dampen or slow down the movement of the magnetic needle. Typically, any bubble will disappear when the compass is returned to room temperature and / or lower elevation. If the bubble remains, as appears to be the case with your compass, it is possible to correct the situation by placing the compass in a warm (not hot) spot, such as a sunny window sill. Do keep an eye on the bubble if it refuses to depart. Should the bubble grow in size, you might have a small, almost imperceptible leak in the liquid-filled compass housing and that means you will need a new compass.

© 1999 Michael Hodgson; All Rights Reserved