Porterhouse Temple Bar also had a cask Dungarvan ale (Helvick Blonde) on gravity dispense when I was there earlier this month - that's where the cask is mounted somewhere, in this case on the back of the bar, and beer is dispensed directly from the cask via a tap on the cask itself.
It can be confusing, because although generally 'cask' refers to beer that still has live yeast in it, unfiltered, and still conditioning away inside the barrel, then dispensed by gravity or handpump with no CO2 intervention, there are occasional practices of putting a filtered/yeast-removed beer into a cask, where no secondary conditioning occurs, and the beer is 'ready to drink' and doesn't need to settle for a few days in the cellar.
Not sure if these are all the correct definitions, but generally when I'm referring to cask ale, I mean a cask-conditioned ale, which has live yeast in the container. The containers normally used for cask-conditioned ale in England (made from metal or plastic most commonly) I'd refer to as casks, firkins or 'nines' (contain 9 gallons). They're also often referred to as barrels, although confusingly barrel can also be a unit of mesaurement which means 36 gallons!
So if I'm seeking a 'cask version of an ale', I mean one that has been allowed to condition in the container and is then dispensed without the use of CO2, preferably handpull or gravity.
