"Tell me, doctor, " said the patient, "when I stand on my head, the blood rushes to it. Why doesn't it rush to my feet now?" "That's because your feet aren't empty," said the doctor.
Sam EwingOn every commercial flight, the traveler is told, "Your seat cushion can be used as a flotation device". The question is, why doesn't the plane just become a boat?
Sam Ewing