When bacteria are grow in an alcoholic beverage in the presence of oxygen they produce acetic acid, which is the acidic component of vinegar. For most of antiquity, vinegar was the only commonly available acid. But as metals came into wider use it became apparent that different metals had different properties. For example, the lead ore we are using in class is mostly lead sulfide, or galena. But it also contains minor amounds of zinc sulfide and silver sulfide.
All metals are more or less soluble in acid, but different metals are soluble in different acids.
So technologically it is very desirable to be able to produce a host of different acids for separating metals from each other. Some say that wherever it is found it is an indication of gold ore, but I cannot approve this a certain. It is mined everywhere from open mines because of evil and unbearable odors like those of sulfur or worse. It's location is recognized by various signs, particularly by its many odors, which show where it is so that it is not necessary to seek it by means other than these and by the sight. He then goes on to describe the extraction of vitriol from its ore by solution and recrystalization in a manner similar to what we have used to isolate potash and lime.