A blind man and some other people were learning how to parachute. They had finished their tuition and were just getting into the aeroplane when the jump master gave them some last minute reminders - "Don't forget, when you're 10 feet from the ground, brace yourself for impact"
The blind man asked "Excuse me but how do I know when I'm 10 feet from the ground?"
Jump master replies "You'll feel your dog's lead go slack"
