Paddy arrives to work on a building site with an object under his arm. Mick says "What's that under your arm Paddy"? "It's a flask" Paddy replies. "What's a flask"? Mick enquires. Paddy explains it keeps hot things hot and cold things cold. Intrigued Mick says" What's in the flask at the moment"? To which Paddy answers " 2 mugs of coffee and an ice cream".