Not exactly a model engineering problem but I'm sure it is just the sort of problem model engineers can probably advise on.
I've a military compass which was fluid filled. It seems to have "lost" its fluid and so the disk no longer "rides" on its pivot.
I'd like to refill it.
Any ideas on what the fluid would have been?
Compass is a handheld beast, a "marching compass", about 3cm in dia. and the "capsule" is about 1cm deep, so about 7 cm^3