A Jamaican walks into a bar and asks the barman for a pint of his finest bitter, the barman obliges and serves him a nice cool pint. The Jamaican takes a couple of sips and and says "eh barman, can you keep an eye on ma pint while a run to the toilet?"
The barman agrees and off he runs. While he's in there, though, a great big muscley black woman strides over to the bar, picks up the pint of bitter, puts it on the floor, squats over it, and let's out a great big loud fart.. then casually picks it back up, puts it on the bar and returns to her seat.
When the Jamaican gets back to the bar he goes to have a sip but the barman, still agog at what he's just witnessed, just stops him in his tracks and explains what's happened.
The Jamaican's furious but sees the size of the woman and is taken aback, nevertheless, he decides he has to say something, so he plucks up the courage, puffs out his chest, strides over and and goes " eh! You fart in ma Whitbread!?"
The lady looks up and says "No, I'm Tessa Sanderson!"