Survival after the end

  There are many science fiction movies about the apocalyptic world. For example, in “I am Legend”, the virus mutated and almost killed all mankind, but the protagonist has innate immunity. After the catastrophe, he survived in the ruins of the city alone and sought to restrain the virus. Methods.
  If one day the end of the world really comes, mankind is almost extinct, and you are one of the few survivors on the earth, maybe only you are left in the entire city. So when you wake up and find that the street is empty, the house has no water or electricity, no gas and no heating, the whole world is desolate, and the silence is terrible. What should you do to survive? What kind of ability do you need to develop and grow, or even recreate human civilization?
  After the first few days of the end: the orientation and diet
  after the end of the first certainly no electricity, because once stopped monitoring and maintenance of power plants will face paralyzed without electricity on the power grid. After a power failure, the backup generator of the Internet server will automatically start, but when the fuel runs out, the Internet will no longer be available. Searching for information online, contacting survivors, etc., will be impossible. The communication base station will also be out of power, and the mobile phone must have no signal.
  However, if you can find clean solar panels, or find a portable generator (such as on some construction sites), then you will have electricity available, and in a short period of time, you can make the home appliances around you operate normally and maintain your life.
  Although the mobile phone has no signal, it can still be used, especially the smart phone can determine the direction and location. The magnetometer in the phone can keep the compass working, and if you download the offline map in advance, the phone will greatly expand your range of activities. Another useful function is GPS navigation. Without maintenance, the GPS satellites in space will still work normally for a while, but the navigation accuracy will continue to decline. After about 6 months, the degree of decline will make the navigation deviation too large and unusable.
  Immediately afterwards, your most urgent need is to prepare bottled water and canned food, as well as a similar outdoor outfit.
  The first few weeks: rural livability
  In the first few weeks, you may encounter other survivors (or maybe months or years later). If you are a stranger, you must be very vigilant, until you are sure of your safety and you have established a foundation of mutual trust, then you can rely on each other to keep warm. At the same time, this will also greatly improve your chances of survival, such as cleaning up the ruins more efficiently and finding what you need.
  During this time, your urban area will definitely be quite disgusting. The corpse is rotten and the stench is pervasive; the pet dog is hungry and scurrying around; the city lighting is paralyzed, the tap water cannot be disinfected, and may even be contaminated.
  The most important thing is that the city is covered with asphalt and concrete everywhere. If there is not enough food supply, long-term survival will be very difficult. So in the post-apocalyptic world, the best place to survive is the countryside. You should find a traditional farmhouse, where you can burn fire for heating and cooking, and you can also grow vegetables and fruits yourself, and raise some livestock and poultry. Of course, you can also go to the city at any time to “clean up” again, bring out useful things as much as possible, and make long-term plans.
  The first few months: safety disinfection
  when the bottled water consumed almost, you have to find new, clean drinking water, we must ensure quality and safety, avoid drinking water infected with pathogenic bacteria. You can boil the water to kill the pathogens in the water, but this will consume a lot of fuel. If you don’t find enough fuel, this is not a good way.
  You can also find water purification tablets in cities to make disinfection easier. After that, you have to learn to use some simple chemical methods to disinfect. You can use kitchen bleach, you can also use swimming pool disinfection drugs (such as sodium hypochlorite, calcium hypochlorite)-in fact, city tap water is disinfected in this way. Of course this must be diluted, otherwise too large a dose may poison you.
  There is a more convenient disinfection method-sunlight disinfection. This is a technology widely promoted by the World Health Organization in developing countries, requiring only a plastic bottle. Fill the plastic bottle with water first, and then put it in the sun for a day or two to ensure adequate sunlight. Sunlight contains ultraviolet rays that will pass through the bottle and kill pathogens in the water.
  In addition, hand washing is also an effective way to inhibit the spread of germs. Use animal oil or vegetable oil, add alkali, and boil it in water to make soap. Alkali is an important chemical substance in human history, it can be extracted from the natural environment. Potash (potassium carbonate) can be extracted from wood fire ash, burned seaweed, or other salt-tolerant seashore plants (such as saphiridia). For example, in Scotland and Ireland, seaside residents have been collecting seaweed for hundreds of years to make soap.
  The first few years: the development of agriculture
  after one or two years if stored out of food, you have to grow their own food. Growing vegetables and fruits is relatively simple and easy, but growing grains is also necessary. After all, this is the staple food, such as wheat, rice, and corn. Grain is actually a kind of grass plant, which grows fast and can produce abundant grains (seeds). For the human body, grains are a very important source of nutrition and energy, because the glucose needed by the human body basically comes from grains.
  Growing grain requires agricultural tools such as plows and rakes. You can search from the ruins of the city, or you can make your own using scrap steel. But the key is that you must ensure that the land is fertile and lasts for years. In the beginning, you may be able to find some fertilizer in the city, but in the long run, you have to use animal manure (including your own) to add fertilizer to the land (nitrates); you can also dissolve bones in acid to make it Phosphate is precipitated and can also be used as soil fertilizer. In addition, regularly sprinkle crushed chalk ash or lime lime on the ground, which will prevent the soil acidity from rising; and plant grains and legumes such as peas, lentils, alfalfa, etc., which will further protect the land and improve fertility .
  With the development of agriculture, sufficient food supply can be guaranteed. If you have contacted other survivors and lived with them, one person may be able to feed 10 people. These 10 people no longer need to be confined to the land, but can focus on other skills, then technology, literature, medicine, etc. will gradually develop, social division of labor will begin to appear, and civilization can hope to flourish again.
  The first ten or twenty years: energy supply
  With the development of agriculture, settlements no longer depend on the objects of urban ruins, and can become self-sufficient and become richer. What is most needed at this time is some traditional skills, such as iron smelting, forging, and engineering skills. Continuous energy supply is also needed. The development of civilization requires a large amount of energy, especially energy brought by mechanical technology, such as watermills, windmills, steam engines, steam turbines, and internal combustion engines. These mechanical energy liberate people from physical labor.
  The energy of early human society basically came from wood, such as acids, alcohols, organic solvents, tar and other important chemical substances, which can be obtained through “dry distillation” (carbonization). Bake the wood in an airtight container, and collect the released steam as the wood gradually turns into charcoal. This gas is an efficient energy source and can be used as fuel for automobiles. During World War II, there were still more than 1 million cars on European roads powered by wood steam.
  In the late 19th century, humans began to use coal and oil in large quantities. But in the post-apocalyptic world, it is clear that there is no need to extract oil anymore, because now all the shallow, easy-to-exploit oil is almost exhausted. However, you can use refined animal oil or vegetable oil to react with methanol and alkali to produce biodiesel to provide fuel for machines. Among them, formaldehyde is also called wood essence, which can be dry distilled from wood; alkali can be produced. You can get quicklime by baking chalk or limestone, and then react it with soap.
  In addition to the main energy, you can also extract some other useful chemicals, such as ethanol. Grain is fermented and then distilled to obtain ethanol (highly concentrated alcohol), which is a versatile organic solvent and a highly effective disinfectant. In addition, charcoal can also play a huge role. Not only can it be used to smelt iron, forge metals, and burn bricks and glass, but it is also a chemical reducing agent that can smelt metals from ore.
  After centuries of doom: the development of science
  hundred years, you probably have gone, but you still ethnic sure how they develop society in the last days? The only way is to observe nature, understand the laws of nature, and transform this understanding into specific principles and laws, and then into practical technology.
  This is actually science, that is, after observing and understanding, design experiments to verify, and then further summarize. In fact, science itself is nature’s unique gift to mankind, by which mankind “invented” a machine for making knowledge.
  For scientific exploration, some tools are necessary, and one of them is absolutely indispensable. This kind of thing is hard, inert, and completely transparent. It is magical glass. Glass is very useful: it can be used to make test tubes and observe chemical reactions; to make thermometers and barometers, to know temperature and pressure (prerequisites for manufacturing technology, such as steam engines and internal combustion engines); to make microscopes and telescopes to expand human vision; Used to study light through reflection and refraction. To make glass, you only need to prepare three raw materials: quartz, soap, and lime. You can collect them from sand, seaweed, and chalk (or limestone).
  With scientific tools, coupled with rational inquiry, apocalyptic society will surely recover quickly from the ruins and avoid repeating the ancient tragedies of human society (such as the dark age of the European Middle Ages). This may take a long time, but as long as human wisdom is used correctly, it is entirely possible to rebuild a prosperous society like today, and even raise it to a new height.