For distillers in the 18th Century, the challenge was not getting crushed by tax revenuers because of a lack of quality devices or understanding of what makes a gallon, something that changed often over the centuries.

Listen as I dig into the history of proof and measuring volume, while we get visits from Alfred Barnard, John Quincy Adams, and I continue my historic journey to all of Ireland and Northern Ireland's active distilleries (save Cooley) and reach the home of Shortcross Gin and Irish Whiskey.