CALLICOON, New York (AFP) – After a lifetime struggling to make money from the land, New York farmer Bill Graby has discovered he's sitting on treasure -- possibly the biggest natural gas deposit in America. "It's like winning the lottery," says the 6.6-foot (two-meter) dairy farmer from the picturesque town of Callicoon in the Catskills hills. The deposit, called the Marcellus shale, stretches all the way from New York to Tennessee, containing 168 to 500 trillion cubic feet of natural gas, according to New York State's Department of Environmental Conservation. That dwarfs the previous big daddy, the Barnett shale in...