Last weekend was my Uncle Jim's 99th birthday. Uncle Jim is one of my heroes. He fought in a tank in North Africa and played bridge with his guards on Christmas Day in an Italian POW camp. When he walks he only needs a walking stick and his own good legs, and when he arranged his birthday party he drew up the guest list by hand and made the calls himself. His mind is clear and his eyes are still good enough to inspect the ladies. When he made his birthday speech he ended it by raising his wine and saying, "Cheers, and may you all live forever."I've written about Uncle Jim elsewhere, so today in his honour I'll tell you about my other favourite old-timer, a rootin', tootin', map-wrangling, whip-smart old fox named Forrest Fenn.Forrest is only 83 years old and lives in Santa Fé, New Mexico. He was shot down over Vietnam and spent nights alone in the jungle, eluding his pursuers, and as soon as he could leave the military he went West to become a trader in treasures and antiquities.When Forrest was seven he found his first arrowhead while hiking in a dry creek, and still has it, along with several thousand others. He's entranced by history, especially the unknown stories that inhere in found objects. He's delighted by the adventure of it, how the past is a treasure hunt and stories are the engines that take you looking.In 1988 Forrest was diagnosed with cancer and given a 20% chance of survival. He gave some thought as to how he'd like to go out, and came up with this: he owned a square cast-bronze 12th-century box, 25cm by 25cm and 12cm deep, for which he paid $25000 in 1980s money. He filled it with various items and artifacts: handfuls of rubies and sapphires, 265 gold coins, a turquoise bracelet won in a pool game, gold nuggets, a pre-Columbian gold frog, a small bag of Alaskan gold dust.His idea was to head into the wild mountain reaches, lie down beside his chest and die. He loved the idea of an outdoorsman coming upon his bones, then reading the note pinned to his chest, bequeathing the treasure to whoever found it, provided they leave his bones where they lie. He would turn himself into a character in one of the adventure stories he read as a boy.His plan was foiled when his cancer went into remission, but 10 years later he came up with a better one. In 2010 he went and hid the chest anyway, and then wrote a book called The Thrill of the Chase, which was part memoir, part personal philosophy about how the pleasure of life resides in the adventure of the quest, part elaborate series of glosses and hints to the location of the chest. It includes a rhyming poem in six stanzas offering nine sequential clues, and a declaration that whoever finds the box can keep it.He paid for the first printing of the book, then signed over all rights and royalties to the small independent bookstore in downtown Santa Fé that he has been visiting since 1978. It has been a massive seller: without it the bookstore would have long since closed.Forrest has lost count of the number of e-mails he has received from members of the public describing their location in Arizona or Colorado or New Mexico and asking: "Am I getting warm?" The search attracts all sorts - the wealthy and the poor, the obsessive and the damaged, the young and the young at heart. His favourite hunters are the families who use it as an excuse to go trailing through the wilderness on weekends, living their own Robert Louis Stevenson or Edgar Allan Poe adventure. My favourite is the man who has been hunting for five years, every long weekend and vacation he gets, who woke one morning in his tent in the crisp morning mountain air with only one fear: that he might find the treasure and have to stop looking. He vowed that if ever he finds it he'll take the turquoise bracelet for his wife and then hide it again and write a new poem.I think it's an extraordinary act of creative generosity, to whisk romance and adventure from thin air and lend it to people's lives. Some suggest that Forrest has made the whole thing up, that the box (despite photographic evidence) doesn't exist, that it's all just an elaborate hoax to encourage people to tramp around the wilderness areas with his name on their lips. Well, let's allow that that's true. My question would be: so what?..