The owner of the Segway company was found dead at the bottom of a cliff in England yesterday, one of his firm's trademark two-wheeled scooters near the body.  Jimi Heselden, 62 years old, apparently accidentally rode off the cliff.  Police say there is no evidence of foul play and are treating the event as a tragic accident.  Heselden was a former miner who quit school at 15 and eventually became a millionaire industrialist.  One of England's richest people, his estate is valued at around $260 million.  The Segway first gained worldwide notice when then-President George Bush the Second tried to ride one and showed himself to be as inept with a Segway as he was with the duties of his office.