If you're looking for a flotation device, you can try this experiment at home, but probably not at your public pool unless their rules around glass bottles and public drinking are more lenient than ours.
Incidentally, our meads are so dry that all of our craft mead will float in the ocean. The only reason the bottles sink is because of the weight of the glass. Craft mead from other companies may not produce the same effect, since it tends to be much denser than our mead due to the higher sugar content.
