Without water your chances of living are nil, and all the food in the area means nothing. This is especially true in hot climates where you perspire a lot. Even in cold weather your body needs at least 2 quarts of water each day; a lesser amount reduces your efficiency. When you cannot find surface water, tap through the earth to the water table for groundwater-rain or melted snow that has sunk into the ground. Access to this table and its supply of water depends upon the contour of the land and the character of the soil. In rocky soil look for springs and seepage. Limestones have more and larger springs than any other type of rock Because limestone is easily dissolved, caverns are easily etched by groundwater. Look in these caverns for natural springs. Because lava rock is porous, it is also a good source for seeping groundwater. Look for springs along the walls of valleys that cross the lava flow. Be on the lookout for seepage where a dry canyon cuts through a layer of porous sandstone. In areas with a lot of granite rock look over the hillsides for green grass. Dig a ditch at the base of the greenest area and wait for the water to seep into it.

Water is usually more plentiful and easier to find in loose soil than in rocks. Look for groundwater along valley floors or on the slopes bordering the valley because the water table is more likely to surface in these areas. Land above a river valley also yields springs or seepage along the base, even when the stream is dry. If you decide to dig for water, first look for signs that it is present. Dig in the floor of a valley under a steep slope, or dig out a green spot where a spring was during the wet season. In the low forests, along the seashore, and in river plains, the water table is close to the surface. Very little digging can yield a good supply of water. Runoff water is found above the water table and includes streams, stagnant pools, and water in bogs. Consider this water contaminated and dangerous, even if it is away from human habitation. Boil or treat this water with water purification tablets before you drink it.

You can find water in the dunes above the beach or even in the beach itself. Look in hollows between sand dunes for visible water, and dig if the sand seems moist. On the beach, scoop holes in the sand at low tide about 100 yards inland of the high-tide mark This water may be brackish, but it is reasonably safe. Run it through a sand filter to reduce the brackish taste. DO NOT drink seawater. The salt concentration of seawater is so high that body fluids must be drawn to eliminate it.

Eventually, your kidneys will cease functioning.

Watch for water indicators when you are isolated in the desert or arid regions. Some of the signals include the direction in which certain birds fly, the presence of plants, and converging game trails. The sand grouse of Asia, crested larks, and zebra birds visit water holes at least once a day; parrots and pigeons must live within reach of water. Note the direction in which these birds fly and chances are you will find something to drink Cattails, greasewood, willows, elderberry, rushes, and salt grass grow only where groundwater is near the surface. Look for these signs and dig. If you do not have a bayonet or entrenching tool, dig with a flat rock sharp stick, your knife, or a spoon. Places that are visibly damp, where animals have scratched, or where flies hover indicate recent surface water. Dig there for water. Collect dew on clear nights by sponging it up with your handkerchief. During a heavy dew, you should be able to collect about a pint an hour.

When you are unsuccessful in your search for ground or runoff water or if you do not have time to purify the questionable water, a water-yielding plant

Figure 6-5.-Extracting water from vines.

may be your best bet. Clear, sweet sap from many plants is easily obtained. This sap is pure and chiefly water. Many plants with fleshy leaves or stems store drinkable water. Try them wherever you find them, Desert plants often have their roots near the surface. The Australian water tree, desert oak, and bloodwood are some examples. Pry these roots out of the ground and cut them into 24- to 36-inch lengths. Remove the bark and suck out the water.

Not all vines yield palatable water, but try any vine you find. Use the following method for tapping a vine. It works on any species.

1. Cut a deep notch in the vine as high up as you can reach.

2. Cut the vine off close to the ground and let the water drip into your mouth or a container.

3. When the water ceases to drip, cut another section off the top.

4. Repeat this until the supply of fluid is exhausted. (See fig. 6-5.)

Figure 6-6.-Wild potatoes.

If the liquid in sap is dark in color, it is not drinkable. If the liquid is clear, test it for odor. When slightly pink or red in color, it probably contains tannic acid. If it has no taste or does not taste bad, then it is a good source of water.

Buri, coconut, sugar, and nips palms contain a drinkable sugary fluid. To start the fluid of coconut palm flowing, cut off the tip of the flower stalk after bending it downward. If you cut off a thin slice every 12 hours, you can renew the flow of liquid and collect up to a quart a day.