Vinegar and its uses where discovered thousands of years ago when wine was left to ferment too long.
The French later began producing vinaigre (vin means wine; aigre means sour) by deliberately leaving wine casks open for a few months and then after filtering it and maturing it began using it. In the mid-1800s Louis Pasteur published a paper on the production of vinegar which is still widely referred to today.
Legend says that Cleopatra bet Marc Antony she could outdo his extravagance by serving a meal that cost 10,000,000 sesterces which was quite a sum in those days. Unable to imagine how one meal could cost so much he took the bet.
The next day Cleopatra him a sumptuous meal that fell far short of the amount that she said it would cost. At some point in the meal a single glass of vinegar was brought in for her. She removed one of the huge pearl earrings she was wearing and dropped it in the vinegar and swallowed it when it had dissolved.
It’s likely to be an urban legend as a whole pearl dropped in a glass of vinegar would take more than a few minutes to dissolve so perhaps this didn’t happen at all. I wouldn’t recommend you trying it out!