BASIC FIRE PRINCIPLES
To build a fire, it helps to understand the basic
principles of a fire. Fuel (in a nongaseous state) does not burn directly. When
you apply heat to a fuel, it produces a gas. This gas, combined with oxygen in
the air, burns.
Understanding the concept of the fire triangle
is very important in correctly constructing and maintaining a fire. The three
sides of the triangle represent air, heat, and fuel. If you remove
any of these, the fire will go out. The correct ratio of these components is
very important for a fire to burn at its greatest capability. The only way to
learn this ratio is to practice.
SITE SELECTION AND PREPARATION
You will have to decide what site and
arrangement to use. Before building a fire consider--
- The area (terrain and climate) in which
you are operating.
- The materials and tools available.
- Time: how much time you have?
- Need: why you need a fire?
- Security: how close is the enemy?
Look for a dry spot that--
- Is protected from the wind.
- Is suitably placed in relation to your
shelter (if any).
- Will concentrate the heat in the direction
you desire.
- Has a supply of wood or other fuel
available. (See
Figure
7-4 for types of material you can use.)

If you are in a wooded or brush-covered area,
clear the brush and scrape the surface soil from the spot you have selected.
Clear a circle at least 1 meter in diameter so there is little chance of the
fire spreading.
If time allows, construct a fire wall using
logs or rocks. This wall will help to reflector direct the heat where you want
it (Figure
7-1). It will also reduce flying sparks and cut down on the amount of wind
blowing into the fire. However, you will need enough wind to keep the fire
burning.
|
CAUTION
Do not use wet or porous
rocks as they may explode when heated. |

In some situations, you may find that an
underground fireplace will best meet your needs. It conceals the fire and serves
well for cooking food. To make an underground fireplace or Dakota fire hole (Figure
7-2)--
- Dig a hole in the ground.
- On the upwind side of this hole, poke or
dig a large connecting hole for ventilation.
- Build your fire in the hole as
illustrated.

If you are in a snow-covered area, use green
logs to make a dry base for your fire (Figure
7-3). Trees with wrist-sized trunks are easily broken in extreme cold. Cut
or break several green logs and lay them side by side on top of the snow. Add
one or two more layers. Lay the top layer of logs opposite those below it.

FIRE MATERIAL SELECTION
You need three types of materials (Figure
7-4) to build a fire--tinder, kindling, and fuel.
Tinder is dry material that ignites with little
heat--a spark starts a fire. The tinder must be absolutely dry to be sure just a
spark will ignite it. If you only have a device that generates sparks, charred
cloth will be almost essential. It holds a spark for long periods, allowing you
to put tinder on the hot area to generate a small flame. You can make charred
cloth by heating cotton cloth until it turns black, but does not burn. Once it
is black, you must keep it in an airtight container to keep it dry. Prepare this
cloth well in advance of any survival situation. Add it to your individual
survival kit.
Kindling is readily combustible material that
you add to the burning tinder. Again, this material should be absolutely dry to
ensure rapid burning. Kindling increases the fire's temperature so that it will
ignite less combustible material.
Fuel is less combustible material that burns
slowly and steadily once ignited.
HOW TO BUILD A FIRE
There are several methods for laying a fire,
each of which has advantages. The situation you find yourself in will determine
which fire to use.
Tepee
To make this fire (Figure
7-5), arrange the tinder and a few sticks of kindling in the shape of a
tepee or cone. Light the center. As the tepee burns, the outside logs will fall
inward, feeding the fire. This type of fire burns well even with wet wood.

Lean-To
To lay this fire (Figure
7-5), push a green stick into the ground at a 30-degree angle. Point the end
of the stick in the direction of the wind. Place some tinder deep under this
lean-to stick. Lean pieces of kindling against the lean-to stick. Light the
tinder. As the kindling catches fire from the tinder, add more kindling.
Cross-Ditch
To use this method (Figure
7-5), scratch a cross about 30 centimeters in size in the ground. Dig the
cross 7.5 centimeters deep. Put a large wad of tinder in the middle of the
cross. Build a kindling pyramid above the tinder. The shallow ditch allows air
to sweep under the tinder to provide a draft.
Pyramid
To lay this fire (Figure
7-5), place two small logs or branches parallel on the ground. Place a solid
layer of small logs across the parallel logs. Add three or four more layers of
logs or branches, each layer smaller than and at a right angle to the layer
below it. Make a starter fire on top of the pyramid. As the starter fire burns,
it will ignite the logs below it. This gives you a fire that burns downward,
requiring no attention during the night.
There are several other ways to lay a fire that
are quite effective. Your situation and the material available in the area may
make another method more suitable.
HOW TO LIGHT A FIRE
Always light your fire from the upwind side.
Make sure to lay your tinder, kindling, and fuel so that your fire will burn as
long as you need it. Igniters provide the initial heat required to start the
tinder burning. They fall into two categories: modern methods and primitive
methods.
Modern Methods
Modem igniters use modem devices--items we
normally think of to start a fire.
Matches
Make sure these matches are waterproof. Also,
store them in a waterproof container along with a dependable striker pad.
Convex Lens
Use this method (Figure
7-6) only on bright, sunny days. The lens can come from binoculars, camera,
telescopic sights, or magnifying glasses. Angle the lens to concentrate the
sun's rays on the tinder. Hold the lens over the same spot until the tinder
begins to smolder. Gently blow or fan the tinder into flame, and apply it to the
fire lay.

Metal Match
Place a flat, dry leaf under your tinder with a
portion exposed. Place the tip of the metal match on the dry leaf, holding the
metal match in one hand and a knife in the other. Scrape your knife against the
metal match to produce sparks. The sparks will hit the tinder. When the tinder
starts to smolder,
proceed as
above.
Battery
Use a battery to generate a spark. Use of this
method depends on the type of battery available. Attach a wire to each terminal.
Touch the ends of the bare wires together next to the tinder so the sparks will
ignite it.
Gunpowder
Often, you will have ammunition with your
equipment. If so, carefully extract the bullet from the shell casing, and use
the gunpowder as tinder. A spark will ignite the powder. Be extremely careful
when extracting the bullet from the case.
Primitive Methods
Primitive igniters are those attributed to our
early ancestors.
Flint and Steel
The direct spark method is the easiest of the
primitive methods to use. The flint and steel method is the most reliable of the
direct spark methods. Strike a flint or other hard, sharp-edged rock edge with a
piece of carbon steel (stainless steel will not produce a good spark). This
method requires a loose-jointed wrist and practice. When a spark has caught in
the tinder, blow on it. The spark will spread and burst into flames.
Fire-Plow
The fire-plow (Figure
7-7) is a friction method of ignition. You rub a hardwood shaft against a
softer wood base. To use this method, cut a straight groove in the base and plow
the blunt tip of the shaft up and down the groove. The plowing action of the
shaft pushes out small particles of wood fibers. Then, as you apply more
pressure on each stroke, the friction ignites the wood particles.

Bow and Drill
The technique of starting a fire with a bow and
drill (Figure
7-8) is simple, but you must exert much effort and be persistent to produce
a fire. You need the following items to use this method:
Socket.
The socket is an easily grasped stone or piece of hardwood or bone with a
slight depression in one side. Use it to hold the drill in place and to
apply downward pressure.
Drill.
The drill should be a straight, seasoned hardwood stick about 2 centimeters
in diameter and 25 centimeters long. The top end is round and the low end
blunt (to produce more friction).
Fire board.
Its size is up to you. A seasoned softwood board about 2.5 centimeters thick
and 10 centimeters wide is preferable. Cut a depression about 2 centimeters
from the edge on one side of the board. On the underside, make a V-shaped
cut from the edge of the board to the depression.
Bow.
The bow is a resilient, green stick about 2.5 centimeters in diameter and a
string. The type of wood is not important. The bowstring can be any type of
cordage. You tie the bowstring from one end of the bow to the other, without
any slack.

To use the bow and drill, first prepare the
fire lay. Then place a bundle of tinder under the V-shaped cut in the fire
board. Place one foot on the fire board. Loop the bowstring over the drill and
place the drill in the precut depression on the fire board. Place the socket,
held in one hand, on the top of the drill to hold it in position. Press down on
the drill and saw the bow back and forth to twirl the drill (Figure
7-8). Once you have established a smooth motion, apply more downward
pressure and work the bow faster. This action will grind hot black powder into
the tinder, causing a spark to catch. Blow on the tinder until it ignites.
Note: Primitive fire-building methods are
exhaustive and require practice to ensure success.
Use nonaromatic seasoned hardwood for fuel, if
possible.
Collect kindling and tinder along the
trail.
Add insect repellent to
the tinder.
Keep the firewood
dry.
Dry damp firewood near the
fire.
Bank the fire to keep the
coals alive overnight.
Carry
lighted punk, when possible.
Be
sure the fire is out before leaving camp.
Do not select wood lying on the ground. It may
appear to be dry but generally doesn't provide enough friction.