Survival depends on you. You must be physically fit and know how to locate or collect water. You must know what plants and animals are available for food, how to find or catch them, how to prepare them, and how to recognize those which will harm you. The more you know about the conditions peculiar to the region you are in, including the plant and animal life, the better are your chances for survival. Water Without water your chances of living are slight, and all the food in the area means little. That is especially true in hot climates where you sweat 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 can’t find surface water, tap through the earth’s water table for groundwater (rain or melted snow that has filtered through the ground). Getting to the water  table  and  its  supply  of  generally  pure  water d e p e n d s  o n  t h e  c o n t o u r  o f  t h e  l a n d  a n d  t h e characteristics of the soil. In  the  desert  or  arid  regions,  watch  for  water indicators. Some signs of water include— Plants covering animal trails and the direction in which certain birds fly. By searching in areas toward which these birds fly, you will probably find water. Places that are visibly damp, where animals have scratched, or where flies hover indicates recent surface water. Dig in those spots for water. Leave  your  handkerchief  out  on  clear  nights  to collect dew; then squeeze the water into a container. During a heavy dew, you should be able to collect about a pint an hour. You may find runoff water above the water table. Runoff  water  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. If you are unsuccessful in your search for ground or runoff  water  or  if  you  don’t  have  time  to  purify questionable water, a water-yielding plant may be your best bet. You can easily get clear, sweet sap that is pure and chiefly water from many plants. 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. 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 will work on any species. 1.  Cut a deep notch in the vine as high up as you can reach. 2.  Then 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 vine. 4.  Repeat this procedure until the supply of fluid is exhausted (fig. 15-10). NOTE If the liquid is a white sap or very dark in color, it is not drinkable. If the liquid is clear, test it for odor. If it is slightly pink or red in color, that normally indicates the presence of tannic acid, which isn’t harmful. If it has no taste, or does not taste bad, it is a good source of water. Food It  takes  little  reasoning  to  recognize  that  your second  requirement  is  food.  That’s  especially  true during a time of survival when you need every ounce of energy and endurance that you can muster. People have been known to live for more than a month without food; but unless you are in extremely difficult  circumstances,  you  don’t  need  to  deprive yourself of something to eat. Used properly, nature can provide you with food. Apply the following rules as soon as you realize you are isolated: 1.  Inventory your rations and water. Estimate the length of time you will be on your own. 2.  Divide your food—two thirds for the first half of your isolation and one third for the second half. 15-18 Student Notes: