Jan. 22, 2012 — My favorite class of all time was Fall and Winter Survival, which I took when I was a senior in high school.

  The class started in the fall and was taught by the coolest biology teachers, who were also avid outdoor enthusiasts.

  We took field trips to local parks and identified native, edible plants — like rosehips and berries.

  We learned how to build fires using only one match. This turned out to be very important during our final exam, a three-day survival solo in the backwoods of Maine in January.

  There was snow on the ground and it rained nearly the whole time we were there. That made building and keeping a fire going critical to both our physical and mental survival.

  When building a fire, you need to amass an abundance of the right kinds of wood. That includes tinder, such as pine needles and birch bark, kindling — branches up to a couple inches thick — and fuel: all the big stuff.

  We learned to break off the dead, dry branches from the underside of conifer trees.

  The trick to building a fire in adverse conditions is painstaking patience.

  Once you’ve coaxed a tiny flame from a scrap of birch bark, you must feed it slowly and carefully, twig by twig. Then, when your fire is going strong, even if your wood is a little bit wet, you can nurse the fire along.

  In Jack London’s short story, “To Build a Fire,” published in 1908 and set in the Yukon, a fire means life or death for the protagonist.

  London’s story taught me not to build my fire directly underneath a tree. If you do, and there is snow built up on the branches, your fire could get smothered if the snow lets loose.

  London’s nameless character is going to meet some friends, a day’s walk away. He sets out with his dog, despite the temperature of 50 below zero. It is so cold that when he spits tobacco juice, it freezes before it hits the ground.

  The man is making good time, about four miles an hour through a foot of fresh snow. Then he gets his legs wet when he crashes through thin ice.

  He knows he must make a fire and dry out his clothes or he will freeze to death.

  His body temperature immediately starts to plummet and his fingers turn so numb it is difficult to separate his matches.

  The man manages to get a fire started, and feeds it twig by twig until it has grown quite large. He is just about to take off his wet boots when the limbs of the tree he made his fire under let loose their snow load and douse the flames.

  The man is shocked, and remembers the words of an old-timer who had told him a man should never travel alone when it is 50 degrees below zero.

  Now the man is afraid. As he starts from scratch to build a new fire, his extremities turn numb and he realizes he might die.

  His fingers no longer have the dexterity to light a match. He is finally able to light a fistful of matches, but cannot feed the fragile flame with dry twigs. His clumsy efforts are no match for the killing cold and his fire dies.

  He sees his dog curled up on himself in an attempt to stay warm. He thinks of a story he heard about a man who survived by slitting open a deer and crawling inside the carcass.

  He calls the dog, but hearing a strangeness in the man’s voice, the dog won’t come. When the man finally does manage to grab the dog, he realizes he has no way to kill it: his hands are so frozen he can’t even hold his knife.

  My own winter survival experience is not nearly as dramatic. The teachers checked on us twice a day to make sure we were OK. It was raining, which was unpleasant, but not life-threatening.

  I had my supplies with me: we’d been allocated one egg, a can of peaches, a package of Jello, a bouillon cube, two small packets of salt and a whole chicken (dead and packaged).

  I had a sheet of plastic, a jack knife, a sleeping bag, my backpack, my journal and six matches.

  Even with an almost constant rain, I was able to construct a shelter, lay pine boughs for a mattress, collect firewood, build a fire and survive through the weekend.

  The unnamed man in London’s story froze to death. He did not heed the old-timer’s advice and paid the ultimate price.

  Alone in the cold, rainy darkness of the woods in Maine, uncomfortable and shivering in my damp sleeping bag, I still knew I was safe.

  Sometimes, we don’t realize the benefit or beauty of a thing until enough time has passed to take the harsh edge off the experience.

  But once that rosy glow has colored our memory, we can sit back and smile, our experience magically transformed from straw into gold.