Mt2Salt, this is an older thread but it doesn't hurt to ask. We keep glass canning jars on our boat and have crossed both the gulf stream
and the Atlantic and no breakage. We keep them in socks or neoprene cozies or an old piece of towel even, in a storage
locker, upright. As long as there is no movement in the locker it works great. That goes for all lockers, no matter what you are stowing. We use towels, clean rags, and lots of rolls of toilet paper and paper towels if we have excess room. Hope that helps!