It's cold enough to freeze whiskey, and you're stuck in the woods without a bag? Make like a pot roast and construct a life-saving fire bed.
[BRACKET "1"] Scrape out a trench in the dirt about a foot wide and 8 inches deep. Line it with very dry, egg- to fist-size stones (wet rocks from a stream or lake can explode when heated).
[BRACKET "2"] Next, burn a fire down to coals and spread a layer throughout the trench. Cover this with at least 4 inches of dirt and tamp it down with your boot. Wait one hour. If the ground warms in less than an hour, add more dirt.
[BRACKET "3"] Check the area twice for any loose coals that could ignite a makeshift mattress. Then spread out a groundsheet of canvas, plastic, or spare clothing. Pine needles or evergreen boughs will work in a pinch.
[BRACKET "4"] Ease onto your fire bed and snooze away.