I was not disappointed with the Sowester Bosun compass I acquired by bidding at Ebay. I took a risk that paid off. When it duly arrived at my doorstep I anxiously opened the parcel to examine the compass which I knew full well had a large bubble under the glass. What I didn’t know was how to go about replacing the missing liquid. I didn’t even know what type of fluid it was. I gambled that liquid from an old, obsolete compass that I had no intention of using would be suitable.
After examining the Bosun compass I discovered that if I extracted two plastic-type screws from the outer side of the casing, the actual compass could easily be removed. I immediately observed a large screw that plugged a hole through which I could replenish the liquid by using a surgical syringe. I undid the screw and administered the life-giving fluid. By gently rocking the compass a little from side to side I could release a few tiny bubbles that remained, and continue filling the bowl until full.
Regarding the nature of the liquid, it certainly was not gin! - More like clear, good quality paraffin, because of that fluid’s characteristic smell. I didn’t notice any difference in appearance or smell between the two liquids. I assume they both have the same viscosity, and I trust there will be no ramifications if they do not.
Just now, I am very happy with ‘Sandpiper’s’ cheap, but practical compass. May that continue as I make use of this essential item.