How to make a cold fire at home. How to make a cold fire

Campfire in field conditions often means the life of a traveler. It is simply impossible to overestimate its importance: the fire of a fire is warmth with which you can warm yourself, it is an opportunity to dry things, cook food. Sometimes fire is just an opportunity to survive. Usually we are used to kindling it with matches or a lighter, which are always at hand (many tourists take dry alcohol or some kind of liquid to kindle a fire with them on hikes). But this is not always at hand, and situations are different. And if suddenly the situation is extreme: the matches are wet, the lighter does not work, the forest around after the rain and everything around is damp? What then? Die from the cold? Or still try to make a fire? But as?

I found on the net a very interesting project from Grigory Sokolov dedicated to non-standard methods of kindling a fire in field conditions - I share it. There are many of them and fire can be obtained almost always. I made a selection of the most interesting methods from his collection, maybe it will be useful to someone.

Method number 1. An old flint lighter that ran out of gas.

The most common situation in the campaign. There was the last lighter, but here's the annoyance - all the gas came out. What to do, how to get fire? The video answers this question. Even an empty lighter can provide you with fire and warmth.

Method number 2. Obtaining fire in a damp forest by friction.

Situation: For making fire, only a knife and a small piece of rope are at hand. It has recently rained in the forest and everything around is damp and wet. Technique - we kindle a fire with the help of friction with a bow.

Method number 3. Getting fire from a battery and a small piece of foil.

Batteries in our time are such a thing that very often are at hand. Know that if you have a battery and some foil, for example from some kind of food packaging, then you also have a fire.

Method number 4. Friction method with wire

A knife and a small piece of steel wire is actually all that is needed to make fire in this way. And yes, a little exercise. 🙂

Method number 5. Method of making fire by rolling cotton wool with chalk

In places where people used to live, in old abandoned houses, you can always find cotton wool. In furniture, mattresses, upholstery. Chalk - whitewashing the walls. With this method, you can get fire.

Method number 6. Getting fire with the sun and a condom

A condom in a campaign is generally speaking a useful thing. In addition to its direct purpose, it can be used as a hermetic bag, as a container for storing water, and below - as a means for kindling a fire in field conditions.

Method number 7. Getting fire with a spoon and the sun.

An ordinary steel spoon, which should be slightly bent, a little soot from a kettle and a piece of toilet paper - that's all that is needed to make fire. Yes, and of course - sunny weather.

Method number 8. Getting fire from the sun and an old gas bottle

The old gas cylinder has one very useful part for this method of making fire. Namely, the bottom. An empty beer can, by the way, will also work.

Method number 9. Fire from the sun and a reflector from a flashlight

It turns out that the reflector of a flashlight, headlight or any other device for directional light is an almost perfect lens for getting fire from the sun.

Method number 10. Fire from the sun and two bottoms of bottles

“Use what is at hand and do not look for another.” (c) Vilias Fog. In this case, the fire is produced from garbage, which is often much more around than required. The design, consisting of the bottoms of two glass bottles, a small amount of water and, of course, the sun may well provide you with fire.

Method number 11. Old light bulb, water and sun.

Old light bulbs can be found in a place where people once lived. And they can do a good job in making fire, if there is nothing else at hand.

Method number 12. Ice + sun = fire!

And finally - a completely extreme technology of making fire. Ice, sun, cleaver and a little hard work. Hardly useful, but very impressive!

Grigory Sokolov - many thanks for the material provided.

Have you ever seen how supposedly gasoline is poured into the palm, ignited, it burns, but a person does not receive any harm from fire? Why don't burns appear on the skin? After all, fire is a high-temperature plasma! What's the matter?

Spectacular focus

The example of fire in the palm of your hand is, of course, impressive. People who are naughty nerves, it is better not to watch such a trick. Or immediately tune in to the fact that this is just a spectacular trick. Even if not entirely clear, smacking of fantasy. Let's break the focus down into its component parts. First, the visual part. What do we usually see?

The magician rolls up his shirt sleeve to the elbow, shows us his palm from all sides. By this he convinces the audience that he has nothing in his palm. Then he takes a glass half-filled with a transparent liquid, shaking it from side to side convinces us that this is really some kind of flammable liquid, since it was said about the flame that he will light in the palm of his hand. Of course, we associate liquid with gasoline or some other transparent liquid flammable substance.

Next, the magician squeezes his palm a little and pours the liquid from the glass into it, puts the empty glass back on the table, takes the lighter, turns the wheel on it and sets fire to the liquid in his palm. It bursts into a voluminous, smoky orange flame. For greater effect, the light is extinguished. We see how a magician in the dark makes beautiful passes with his palm with a flame, then instantly clenching his palm into a fist and the flame goes out. Lights flash, the magician bows to the applause of the audience.

Now we analyze the second part of the focus - the chemical one. The magician poured ordinary water from a glass into his palm! But it won't light up! However, we did not notice that a small cotton ball soaked in a mixture of carbon tetrachloride and cyclohexane in equal proportions, taken from the table along with a lighter, fell on the palm of our hand. Having poured water into the palm of his hand, the magician imperceptibly drained it, and the cotton ball began to evaporate a certain substance, releasing a combustible gas. The magician sets it on fire. The gas burns for a few seconds without causing any harm to the palm. Clenching his hand into a fist, the magician sharply limits the access of air to the flame - the fire goes out. With water on the palm of his hand, he only moistened the skin. Otherwise, a mixture of carbon tetrachloride and cyclohexane would have penetrated into it and there would have been a rather severe burn. The peculiarity is that the burning did not take place on the skin of the palm itself, but at some distance from it. And since, according to the laws of physics, heat tends upward, a layer of cold air appeared between the palm and the flame.

Another way to repeat this trick

It should be noted that the mixture of carbon tetrachloride and cyclohexane is toxic. For this reason, the focus is placed in a very large, well-ventilated room. For example, in the circus arena in the pauses between performances, when there is forced ventilation with the help of powerful mechanisms.

Less dangerous focus with the use of ethyl ester of boric acid. But its vapors do not burn with a yellow, but with a greenish flame, which is not so spectacular. For the preparation of boric acid ethyl ester in a strictly defined proportion, dry boric acid itself, ethyl alcohol, concentrated hydrochloric or sulfuric acid are used. The mixture releases ether vapors that are not visible. The resulting aerosol burns. This fire does not burn the skin at all. But if after some time (a matter of seconds!) You do not block the access of air to the mixture, ethyl alcohol itself will start to burn, which will result in a guaranteed skin burn.

As you can see, cold fire tricks are very effective in the dark, but require excellent reaction. During their demonstration, an assistant with a wet towel is always next to the magician - in case the magician does not have time to quickly extinguish the flame and gets burned.

Spring is here, which means it's time to get outdoors. What to have fun in nature, except for the field kitchen and the arrangement of the camp? We suggest you try several ways to make a fire without matches and lighters. It's exciting, and most importantly, if the result is positive, you will get invaluable experience that may someday come in handy in your life.

Every experienced hunter, fisherman, and just an avid traveler should know how to make fire without matches. This is the basis of survival in any unforeseen situation. Fire is life, and it is extremely difficult to do without it in harsh field conditions. Matches can simply get damp, and then traditional and not quite traditional methods and ways of making fire come to the rescue. Some of the methods described below have been known to man since ancient times, and some are the know-how of modern times, they were invented recently and in some respects are not inferior to traditional methods of making fire. Lighting a fire without matches is a painstaking and time-consuming task. You can find yourself in the wild under absolutely any conditions, and only a fire can save a person.

1. Making fire with friction

This is perhaps the most famous and affordable way to get fire. It is long and painstaking, so you need to prepare for the fact that it will take a lot of time to get the first spark.

There are certain criteria for the success of such an event, one of which is the right choice of wood as a rod and plank. The wood should be dry, not damp. A rod is called a wooden stick, which will have to be twisted on a plank around its axis in order to make fire, creating the effect of strong friction.

The best types of wood suitable for making fire by friction are walnut, cypress, cedar, willow, aspen, pine.

It is necessary to collect tinder in a compact pile. Do not put too much tinder on the wood substrate. Tinder itself is made from dry leaves or grass, it is a light material that must be ignited by a spark. A V-shaped hole is cut into the wooden substrate and a little tinder is placed in the recess of the hole. After that, the wooden rod is placed in the recess and the rotation of the rod begins. To rotate the rod with your hands more conveniently, you need to take a wooden stick to create a rod with a length of at least sixty centimeters. It is necessary to press the rod on the wooden substrate very carefully, while quickly rotating it between the palms.

After a spark is obtained, dry moss, juniper, aspen bark should be placed on the board.

Another interesting way to make fire without matches is the Fire Plow. To make fire using this method, a wooden substrate made of dry wood is useful, in the middle of which a recess for the rod is cut. You have to forcefully move it up and down. As soon as the tree begins to smolder, it is necessary to put tinder.

A bow drill is another versatile way to make fire without using matches. Unlike manual friction, getting a spark from a bow is faster. Since the bow maintains ideal pressure and maximum rotation speed of the wooden rod. As a result, there is strong friction, which helps to make fire in a short time. What is needed for this method? This is, first of all:

  • Wooden rod;
  • Wooden substrate;
  • Bow and weighting agent;

During friction, the weighting agent is pressed on the end of the rod, and the rod rotates with the help of a bow. In order not to break the rod, it is necessary to take a less dense and solid weighting agent.

You can use water or oil as a lubricant, so the process will go faster. Let's talk about the bow itself. You can do it yourself. The length of the bow should correspond to the length of the arm of an ordinary person. It is better to choose a flexible and pliable vine, the bowstring is made of rope, shoelace. The bowstring can be made of absolutely anything, but it must be strong and not break during the making of fire. It is simply pulled over the ends of the vine branch, and the bow is ready to use. A hole is cut in the wooden substrate, the wooden rod is placed in the loop of the bowstring. One end of the rod should fit in the hole in the backing, and the other end in the string of the bow. The bow moves in a progressive motion, and through this process, fire can be quickly produced. Tinder is added to the embers, and the fire slowly but surely flares up.

2. Making fire with lenses

We all know the standard physics course at school, from which we remember that a beam of solar energy passing through glass is concentrated at one point. The temperature is so high at this point that it is enough just to bring a paper napkin to it and it will light up. This method of producing fire is good for everyone, but there is also a significant minus. You can get fire with a lens only in dry and sunny weather. What will be required?

  • Lens of any type;
  • Tinder collected from dry leaves or grass;

If you don't have a lens, regular glasses, a piece of glass, the bottom of an aluminum can, and even ice will do. By the way, you can stop in more detail about the extraction of fire with the help of ice. It would seem that these are two mutually exclusive concepts: ice and flame. But thanks to the ice, you can kindle a fire, this is especially useful in winter, when it is difficult to find dry leaves or grass. The principle of operation of such an interesting method was also described by Jules Verne. You need to create a lens from ordinary ice, but the ice should be as clean and transparent as possible.

Thanks to the coordination of the sun's rays, even paper can be set on fire. It is not always possible to find pure ice in nature, but you can freeze plain drinking water. The resulting piece of ice is carefully processed and polished with improvised means. Ice can also be frozen in a spherical container, such as a shallow saucer. But you need to remove the ice as carefully as possible so as not to damage it. The ice melts quickly and such a lens should be used as quickly as possible.

As for simple lenses, it is enough to take just a few dry twigs, leaves, grass and build something similar to a nest. After the lens is aimed at the tinder, one must carefully monitor the appearance of smoldering and smoke, try to fan the fire.

3. Making fire with chemicals

A simple knowledge of elementary chemistry will help you make fire. Some chemicals ignite when rubbed or mixed. But when using this method, individual care must be taken so as not to harm yourself. It is important to avoid physical contact of the chemical with the metal surface. The following compounds contribute to inflammation:

  • Potassium permanganate (potassium permanganate) and regular sugar in a ratio of nine (sugar) to one (potassium permanganate);
  • Potassium chlorate and sugar (proportions three to one);
  • Potassium permanganate and glycerin;
  • Sodium chlorate and sugar (proportion three to one);
  • Potassium permanganate and any antifreeze;

Now the question is: where to get these chemical elements? Potassium chloride is part of some preparations against throat diseases (Furacillin). And potassium permanganate and glycerin can be found in the first aid kit. The most elementary example: we take a small piece of cotton wool, pour potassium permanganate, then sugar and begin to rub such a kind of tinder with a stick.

After a couple of minutes, the cotton wool will ignite. A typical mistake of inexperienced people is that they do not follow the correct dosage of ingredients.

4. Getting fire with a flint, flint or flint

Another way, rooted in a long history: making fire with a flint and flint. The flint and steel were especially popular in the eighteenth century before the invention of ordinary matches. To strike a spark and build a fire, it is enough to have a stone made of silicon. A couple of blows are enough and you can bring tinder from leaves or dry grass to start a fire. The flint and steel were often used in field conditions or in war. And also, many wear it in theirs. The armchair must be metal.

If you're lucky, you can strike sparks for the future fire using silicon. Flint, consisting of hard rocks of minerals, can be easily found among stones. By the way, flint flint was used in ancient firearms.

5. Condom

After we have considered the traditional and quite familiar ways of making fire without matches, we can turn our attention to alternative methods of making a flame. Let's talk about the most interesting of them. A condom is not only a means of protection, but also an excellent tool for making fire without matches. It must be filled with water, the main thing is not to overdo it.

The result is a kind of lens. Light from the sun passing through the condom is focused on the pre-cooked tinder on the wooden substrate. As a result, the tinder begins to slowly smolder, it remains only to fan the flame of fire. This is such an interesting and creative way.

6. Flashlight

You can get fire with a regular flashlight, if you, of course, do not feel sorry for him. The flashlight will have to be broken. The electric part of the light bulb on the lantern is carefully broken (we need to expose the electric arc itself).

We quickly place a little tinder, bring a bare arc and set fire to the tinder.

7. Skating

Not by washing, so by skating! In this case, you will need ordinary cotton wool. This old prison know-how is that a kind of roller is formed from a simple piece of cotton wool.

The roller begins to roll over the surface of the wood. After a while, the cotton wool begins to smolder, the cotton wool increases in size, being saturated with oxygen. Oxygen itself is a catalyst for the combustion reaction.


8. A can of Coca-Cola and a bar of chocolate.

How can these delicacies help in making fire, you ask? Everything is very simple. The components of success are a sunny day, chocolate and a soda can (tin). Open the chocolate and begin to rub it on the bottom of the can. Of course, it’s a pity for chocolate, but what you don’t have to sacrifice for the sake of producing fire!

Such cunning polishing will make the tin bottom shiny and shining. After polishing, the Coca-Cola can turned into a kind of parabolic mirror. We turn the polished bottom towards the sun and try to set fire to the previously prepared tinder.

8. Wool and batteries

Wool and ordinary batteries can also come in handy for the difficult task of making fire without matches.

We simply stretch the woolen fabric (it is desirable that the wool be natural) and begin to quickly rub a piece of wool with a battery. The optimal battery power suitable for such actions is approximately 9 watts. Wool, after long efforts, slowly begins to ignite, it remains to lightly blow on it and put tinder so that the fire starts faster.

10. Firearms

You can get saving fire if you have a firearm. It’s just that a shot is removed from the cartridge itself, the sleeve can be stuffed with tinder in the form of dry moss, leaves, folded dry bark and a blank shot is fired at the place where it is planned to make a fire. The rest is just a matter of technique, it is necessary to fan the fire and throw dry branches into it.

A rather exotic at first glance method, but still very effective in emergency situations.

As you can see, there are many ways to start a fire if there are no matches. It is important to know some elementary rules, folk tricks and tips that can keep you warm in the forest or even save your life if you suddenly get lost. The experience accumulated over the centuries allows you to get a saving fire from almost any improvised materials. This does not require special skill, it is important to apply the maximum amount of effort to produce fire. Fire is life. And a cheerful, crackling fire will warm you in any situation and in any weather.

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Cold fire is a special type of low-temperature flame. Such a fire is "manual": you can touch it, hold it in your hands, play with it. Probably, each of you has seen films or cartoons, the characters of which released fireballs from their hands. Of course, all this is the result of the work of computer graphics industry professionals, but today, thanks to such a science as chemistry, we will tell you how to make a cold fire at home.

You will need:

We are preparing the base on which we will apply the finished mixture. The fact is that cold fire can cause significant damage to the skin if it is bred directly on the hand. So for this purpose we will build a small ball.

To do this, we wind a fairly dense woolen thread into a ball. A ball, 2-3 centimeters in size, is enough for 3-4 minutes of burning.

If you don’t want to take risks and touch the fire with your hands, you can build something that looks like a torch by planting a ball on a knitting needle or a thin long stick.

We proceed directly to the preparation of the mixture for a cold fire.

To do this, pour a tablespoon of ethyl alcohol into a small container. We add the same amount of boric acid, and only after that - a drop of hydrochloric or sulfuric. It is very important to maintain proportions and mix all the ingredients thoroughly, as we are dealing with very unstable and strong chemicals.

Next, we need to heat the resulting mixture. To do this, it is best to use a water bath (2-3 minutes will be enough). To check the temperature, dip your fingertip into the mixture: if you can stand it for a few seconds (does not burn much), remove it.

Wet the balloon with the solution. Before setting it on fire, keep in mind that hydrochloric acid (or boric acid, depending on which one you used) will start burning first, the flame from which is almost insensitive. But after that, alcohol will light up, which, when burned, can seriously burn the skin. So as soon as you begin to feel a slight burning sensation, put out the ball, or lower it into a specially prepared empty container.

Everyone should know how to kindle a fire - with such knowledge you will not be lost. A real dude definitely knows how to start a fire without matches. This is a necessary skill for survival. It is impossible to guess when you need to build a fire, and there will be no matches at hand. Maybe your plane will crash in some wild area, like somewhere in Alaska. Or, for example, you go into the forest and lose your backpack in a fight with a bear. Eventually, you may end up in very windy or wet conditions where matches are practically useless. It doesn't matter if you ever need these skills, but it's still very cool to know how to make fire, no matter what conditions you are in.

Making fire by friction
Making fire by friction is not for the faint of heart. Perhaps this is the most difficult of the "non-match" methods of making fire. There are different ways to make fire by friction, but the most important thing in this matter is what kind of wood to use as a plank and rod.
The rod is a stick that needs to be twisted back and forth around its axis in order to create strong friction between it and the plank to produce a spark. If you create a strong enough friction between the rod and the plank, you can get embers and use them to start a fire. Poplar, juniper, aspen, willow, cedar, cypress and walnut are best suited for making fire in this way.
An important point: the wood must be dry.

hand drill
The hand drill method is the most primitive, simple and at the same time the most difficult. All that is needed for that method is a tree, strong hands and iron patience. Applying this method, you will feel like a real primitive man. So, we make fire with a hand drill:
Gather the tinder into a compact pile that resembles a bird's nest. The nest of tinder will be used to ignite the flame obtained from the spark that we have to extract. Such a "nest" should be made of material that catches fire easily, such as dry grass, leaves or bark.
Make a small indentation in the "nest". Cut a v-shaped hole in the fire board and make a small indentation next to it.
Place the bark under this depression. Smoldering coals arising from the friction of the rod against the board will fall on it - this will give the fire a chance to flare up.
Start rotating the rod. Place the rod in the recess on the plank. The length of the rod must be at least 60 cm for everything to work properly. Press the rod against the plank and rotate it between your palms, moving them quickly up and down the rod. Keep doing this until embers form in the hole of the fire board.
Fan the fire! As soon as you see the red coals, knock on the fire board so that they fall on the piece of bark located under the hole. Move the bark to your "nest" of tinder. Carefully and carefully blow on the coals to start the flame.

fire plow
Prepare the board for the fire. Cut a hole in the board where you will put the rod.
Three! Take a rod and place its end in the recess on the fire board. Start rubbing the tip of the rod against the walls of the recess in the plank, moving it up and down.
Start lighting a fire. Position the "nest" of tinder so that smoldering embers, which will arise from friction, fall into it. As soon as you catch an ember, gently blow on it - and get a small tongue of living flame.

bow drill
The use of a bow for making fire is probably the most effective of the friction methods, because it is easier to maintain a high pressure and speed of rotation of the rod. There is a strong friction necessary for making fire. In addition to the rod and plank, this method will require a weighting agent to hold the rod, and a bow.
Make a weight device. It is used to put pressure on the end of the rod that will be on top: the rod is set in motion with the bow and because of this it becomes unstable. To hold the rod, you can use a stone or a piece of wood. If you use a piece of wood, it must be harder than the rod. It is very good to use water or oil as a lubricant to make things go better.
Make a bow. It should be the same length as your arm. Use a flexible, slightly twisted wooden vine. The string of a bow can be made from anything, such as cord, rope, or a strip of rawhide of rough tanning. One condition: it must be a durable material that will not tear. Stretch the string and you're ready to start making fire.
Prepare the board for the fire. Cut out a v-shaped hole, place tinder under the hole.
Wrap the rod with a bowstring. Place the rod in the bowstring loop. One end of the rod should be in the hole that you made in the plank, and the other end should be pressed with a stone or piece of wood.
Start moving the bow. Move the bow back and forth in a horizontal plane, just like when sawing something. As a matter of fact, now you have assembled an elementary mechanical system. The rod must rotate quickly. Keep moving the bow until you get coals.
Set the fire on fire. Throw the embers into the tinder and lightly blow on them. Ready! Now you've lit the fire.

Flint and steel

This is the old method. Having a good flint and steel with you is always a good idea. Matches can get wet and they're useless, but then you can still rely on your flint and steel.
If these things were not at hand, no one forbids you to improvise using quartzite and the steel blade of a pocket knife.
You will also need a fire starter, usually cloth or moss. They catch a spark well and smolder for a long time without flaring up. If you do not have special material for ignition, then a piece of mushroom or birch bark is quite suitable.
Fix the ignition material and stone. Grab the stone with your thumb and forefinger. Make sure that the distance from the fingers to the edge of the stone is approximately 5-7 cm. The ignition material should be between the thumb and the flint.
Bay! Take a steel bar or use a knife handle. Hit steel on flint several times. Sparks will fly off the steel and land on the ignition material, causing smoldering.
Kindle the fire. Place the fire starter material in the tinder "nest" and lightly blow on it to fan the flame.

Making fire with a lens

Lighting a fire is easy with a lens. Anyone who melted plastic soldiers with a magnifying glass as a child knows how to do it. If you have never done such things, then here is the instruction for you.

Traditional lenses
All that is required to produce fire is a lens, which is necessary to concentrate sunlight on a certain place. A magnifying glass, glasses or binocular lenses are fine. If you add a little water to the surface of the lens, you can enhance the beam.
Rotate the lens at an angle to the sun to focus the beam on as small an area as possible. Place a "nest" of tinder to this spot, and a fire will soon flare up.
The only downside to this method is that it only works when there is sun. Therefore, if it happens in the evening or on a cloudy day, the lens will be useless.

In addition to the simple method of making fire with a lens, there are three additional methods of making fire with a lens that also allow you to make fire.

Balloons and condoms
By filling a balloon or a condom with water, you can turn these simple things into a lens that will help start a fire.
Fill a condom or balloon with water and tie off the end. Give the ball or condom the most spherical shape. Do not inflate the condom or balloon too much, as this will distort the focus of the sun's beam. Squeeze the balloon into a shape that will focus the beam. Try to squeeze the condom down the middle to form two smaller lenses.
Condoms and balloons have a shorter focal length than ordinary lenses, so they should be placed 2-5 cm away from the tinder.

Making fire with ice
Ice and fire is not only a quote from Pushkin, which you probably remember from a school literature course. With the help of a piece of ice, you can actually make a fire. All you need to do to do this is to shape a piece of ice into a lens and then use it for its intended purpose, like any other lens. This method is especially good for hikers in the winter.
Get clean water. In order for ice to be made into a lens, it must be transparent. If the ice is cloudy or contains any impurities, then, no matter how hard you fight, you will not get fire with it. The best way to get a clear piece of ice is to fill a bowl or cup with clear water from a lake, pond, or melted snow and let the water freeze. A piece of ice should be about 5 cm thick to serve as a good lens.
Shape a piece of ice into a lens shape with a knife. Remember that the lens is thicker in the middle and narrower near the edges.
After you get a rough lens, polish it with your hands. The heat from your hands will melt the ice enough to create a nice smooth surface.
Start making fire. Set the ice lens at an angle to the sun in the same way as if it were a normal glass lens. Concentrate a beam of light on a pile of tinder and see how useful it is to remember Alexander Sergeevich's quote.

Coca-Cola can and chocolate bar
I saw this way in a YouTube video, quite an interesting thing. All we need is a can of Coca-Cola, a bar of chocolate and a sunny day.
Open the bar of chocolate and start rubbing the chocolate itself against the bottom of the jar. Such polishing will make the surface of the tin bottom shining like a mirror. If you don't have chocolate with you, toothpaste works the same way.
Get fire. After polishing, you essentially got a parabolic mirror. Sunlight will bounce off the bottom of the jar and focus on one spot. This is somewhat reminiscent of the principle of operation of mirrors in a telescope.
Turn the polished bottom of the jar towards the sun. This way you will create a perfectly focused beam of light aimed directly at the tinder. Place the tinder at a distance of approximately 2-3 cm from the focus of sunlight. After a few seconds, a flame should appear.
While I can’t imagine that I ended up somewhere on the edge of the world with a can of Coke and a chocolate bar, but this method of making fire really works.

Batteries and natural wool

As with chocolate and a bottle, it's hard to imagine a situation in which you can find yourself in extreme conditions without matches, but with batteries and a piece of clean wool. But you never know how life will turn out. This method is quite simple and fun, so you can try it at home.
Stretch a piece of wool. It is necessary that the strip of wool be approximately 15 cm long and 1 cm wide.
Rub the battery with a piece of wool. Hold the strip of wool in one hand and the battery in the other. Any battery will do, but the optimal power is 9 watts. Rub the side of the battery with the "contacts" with wool. The wool will ignite. Lightly blow on it.
Transfer the burning wool to the tinder. Wool will not burn for long, so hurry up!