COMPASS problem.

[leigh47]

I have an old ships compass (about 6" dia.) that has a large air bubble inside.Can anybody tell me what liquid should be used to refill.

[Clanad]

Original "wet" compasses used in aircraft are called "whisky" compasses sometimes because the liquid in which the magnet floats is alcohol... this is used to avoid freezing.  Sometimes, I've seen the compass filled with mineral oil as well...

[landie]

Otherwise you could inject extra bubble to fill the space.

[BadlyHungBoy]

I think they're meant to have an air bubble:-/ If it's so large that it doesn't work then you'll need specialist advice. It certainly is alcohol that's in there: diehards have been known to "Drink the compass" which, apparently, guarantees they won't lose their way home!