Some years ago an acquaintance who was married to a French woman, commented that as was the custom in the French countryside, they normally dumped whatever dregs remained in wine glasses into a container, I think he said they used an old crockery jar, and this became their vinegar. My question is this, how? In other words, is there more to it than simply letting time run it course? I inferred that this was an ongoing process, that they continued adding leftover wine, without extracting the vinegar except as needed. Can anyone tell me more on this? Thanks