Trapper's bivouac - sleeping bag, ranger's tent and bivouac fire. These are enough to let you sleep comfortably through a cold night. If you are to be truly at home in the outside, you should learn how to build a shelter for yourself. There is no genuine trapper or ranger who has not spent at least one night sleeping under the sky. We've all read stories about the weary traveler who "dug a hollow for his hips in the soft ground and slept until dawn."

Even this primitive sleeping arrangement calls for some knowledge of how to adjust to the prevailing conditions. Try lying down on the bare ground to sleep. You will notice quickly enough that the hip bone on whichever side you are lying is in your way. Dig out a depression, just big enough for your hip bone, and you will immediately notice how much more comfortable you are. You can go one step further, and cushion the hole with some fine sand, or you can place some slightly crumpled paper in the hollow for insulation against the cold.

You can be even more comfortable if you put up a ranger's tent, which requires very few materials. All you need is a rectangular piece of cotton cloth, 6 or 7 feet long. To waterproof it, make a brew from the bark of an oak or birch tree, and let the cloth soak in it for two days. The ranger's tent can then be used as a raincoat too.

In one corner make an eyelet large enough to run a thick cord through. At the other three corners, sew on small leather loops that you will attach to the tent pegs.

With this cloth, a solid cord 10 to 14 feet long, and a few pieces of branches from which you can cut your own tent pegs, you will have sufficient equipment to sleep out pleasantly on even a cool summer night without having to worry about a cloudburst. Set the tent up as pictured in the illustration.

The way you pitch the tent is important. The entrance must remain open and the tent should narrow toward the rear, so you must always be careful to have the opening turned away from the windy or storm side. To keep out the cold, you can hang a raincoat or windbreaker in front of the opening, or put your rucksack in front of it. There's an even simpler way: gather some leafy limbs and branches and, after you crawl into the tent, close off the entrance with them, sticking them in the ground like a fence in front of the opening. You can also do as rangers do. In cold weather they just light a fire in front of the tent entrance and lay a few thick, dry branches on the coals before going to bed. If the tent is set up right, the wind will carry the smoke away from it.

The choice of a camping site is important. The earth should not have too much clay, or it will keep the water from being absorbed. And don't camp in the middle of a hollow where the rain water can collect. Loose, sandy ground is warm and comfortable. It is pleasant to have a wooded area or a rise in the ground to protect you from the storm side. In northern latitudes, the storm side is the west, northwest, or southwest.