Pot Stills are used to make malt whisky, Cognac and funky Jamaican rums, to name just a few spirits. They work in batches, i.e. you need to load stills full of wash or spirt, run them, then reload them. Column stills, on the other hand, can run continuously. Scotch distilleries run pairs of stills. Wash stills, the first set, takes turns the “wash,” up to low wines, which are 20-30% ABV. The next set turns out the final spirit, which usually comes off the still above 60% ABV.