After a long sea passage the old sailor took himself ashore for a few beers
and a bit of female company....

Some time later he's puffing and panting away on top of this lady of ill
repute, and he says.. 'how am I going there , girlie?'

'Three knots..' she says.

'Three knots??' he asked.

"Yes, you're not hard, you're not in and you're not getting your money
back........."