The Drunken Lizard Pub

Ok, thanks!

If I click a keg of blackpowder when I'm holding a bow, it says: "You see a keg of blackpowder." How can I shoot it?

I did the puzzle with the torches in the mysterious cave, but I can't get any further because there are kegs of blackpowder which explode when I come close. Is there a way to get past them safely?