An ideal world in which there would be no need to give birth to children - people would simply find ...
Fight for fire
The Significance of Fire in Human Evolution - An Integrated Lesson*
Equipment.
Musical excerpts: L. Beethoven, ballet "The Creations of Prometheus", or A. Scriabin, symphonic work "Prometheus" ("Poem of Fire"), or F. Liszt, symphonic poem "Prometheus".
Related texts (see Appendices), geographic map deserts and semi-deserts, reproductions of drawings from the sites of ancient people in Africa.
DURING THE CLASSES
In a darkened classroom, a candle burns on the teacher's desk. The teacher (or a student with artistic abilities) expressively reads an excerpt from the book by J. Roni Sr. "The Fight for Fire" (Appendix 1). After the passage is finished, the candle is extinguished. For a while the class is plunged into darkness. Then candles are lit on the tables of students sitting in groups.
Teacher. Guys, imagine how our ancestors sat by the fire and looked at it in fascination ten thousand, a thousand, a hundred years ago - just like we are looking now ... In our electrical life, there are fireplaces, candles, even flickering electric fireplaces with fake firewood. Wild animals are afraid of fire; the domesticated get used to it; Only dogs are innately fond of fire.
Zoologists say that man is unique in the animal kingdom in two manifestations - he uses speech and fire. The use of fire is utilitarian, but the craving for fire in humans is unconscious, instinctive. This is the only instinct that animals do not know. Human instinct. It originated with our distant ancestors and has been preserved with us. But as soon as it was not refracted in consciousness! Cults of fire worshipers. The destructive bliss of the pyromaniacs. Rome set on fire and rebuilt. Pioneer fires. Eternal flame in honor of the fallen...
Let's go back to an excerpt from the book by J. Roni Sr. "The Fight for Fire."
A discussion begins (texts with an excerpt from the book are on the tables of the students). The teacher asks questions, students work with the text, answer.
How did these people keep the fire?
(Answer. In special cages: four women and two warriors fed him day and night.)
What was the meaning of fire for ancient people?
(Answer. Fire scared away predators, helped on the way, made it possible to cook more delicious food, fire was used in the manufacture of tools, it created a sense of community among people.)
What means of expression does the author use when describing fire?
(Answer. Personification, comparison. Fire-beast: "mighty face", "red teeth", "breaking out of the cage", "devouring trees", "cruel and wild". "Father, guardian, savior")
What means of expression does the author use to denote a dying fire?
(Answer. Personification with an animal: weakened, turned pale, decreased, “trembled like a sick animal”, “a small insect.”)
How is the grief of the Ulamr conveyed in the text?
(Answer.“No stars”, “heavy sky”, “heavy waters”, “cold light”, “chalk layers of clouds”, “fatty, like mountain tar, waters”, “algae abscesses”. Sound writing: cold stems of plants, the rustling of reptiles, petrified lizards, withered wood, plants trembling from the cold.)
The teacher leads the class to a general conclusion: fire was personified among ancient people with a living being, which has life and death.
Setting goals and objectives of the lesson. Consider the problem of the positive and negative effects of fire on human evolution, narrowing it down to the positions of "Fire-life" and "Fire-death".
Organization of work in groups. Previously, the class is divided into three groups (optional): supporters of the positions "fire-life" and "fire-death" and observers (arbitrators, judges). Symbolic scales are set on the teacher's table, black and white balls are placed nearby.
Mythological interpretation of a person's ability to control firefire-life ( statement by representatives of the group defending this position). The question of how long we have owned fire has worried mankind for many millennia. One of the proofs of such searches is the "Legend of Prometheus". Reading ( against the background of the musical work "Prometheus") and discussion of the text "Prometheus" (Appendix 2). Conclusion: the fire brought the mind to humanity. White ball. ( The representative of the "Fire-Life" group puts a white ball on the scales.)
Atlas and Prometheus tormented by the eagle of Zeus
fire-death ( performance of students from the group adhering to this position). The mythological interpretation of the image of Prometheus is far from being so unambiguous. In Hesiod, Prometheus is a cunning, albeit kind to people, deceiver of Zeus, punished by him not without reason. Moreover, in antiquity there was a tradition (it belongs to Roman authors) of a condemning image of Prometheus. For Horace, the defiant Prometheus committed an "evil deceit" by bringing fire, with disastrous consequences. Creating a man, he put into him the "malice" and "madness" of a lion. Prometheus only cared about human body, and hence all the troubles of human life and enmity among people. Black ball. ( Having completed the performance, the representative of the Fire-Death group puts a black ball on the other side of the scales.).
The Significance of Fire in Human Evolution
Teacher. The earliest traces of the use of fire are found in a South African cave. Below the level corresponding to the time of 1.3-1.0 million years ago, no such traces are found, but above this horizon there are bones that have been fired in a bonfire. The use of fire was a technological achievement second only to the invention of stone tools. In the Zhou-Gou-Tien cave in China, where the remains of Sinanthropes and their numerous stone tools were found, traces of fire were also found: coals, ashes, burnt stones. Obviously, the first hearths burned here more than 500 thousand years ago.
Fire is life. The ability to use fire made food more digestible and tasty. ( white ball.)
Fried food is easier to chew, and this could not but affect the appearance of people: the selection pressure aimed at maintaining a powerful jaw apparatus has disappeared. Gradually, the teeth began to decrease, the lower jaw no longer protruded so much, the massive bone structure required for attaching powerful chewing muscles was no longer necessary. The person's face acquired modern features. (White ball.)
The main advantage of the ape-man was the increased migratory ability. A big game hunter, one of the predators of the highest order, he increasingly left the tropical zone for high latitudes - hunting was more productive there, since with a decrease in species diversity, the number of each species increases. However, it was cold there, and the Pithecanthropus had to adapt to the cold. It was this ancestor of ours who learned to keep the fire of forest fires and volcanic eruptions and use it. But the Pithecanthropes themselves did not know how to make fire. Fire made man independent of the climate, allowed him to spread over the entire surface of the Earth. ( White ball.)
Fire not only expanded the availability of food sources many times over, but also gave mankind constant and reliable protection from wild animals. People used the flame to protect themselves from large predators-competitors, they could use it to win back comfortable dwellings - caves from animals. ( White ball.)
With the help of fire, people could produce more advanced tools. For example, the wooden spearheads and the ends of the spears burned in the fire were made harder. ( White ball.)
With the advent of fire and the hearth, a completely new phenomenon arose - a space strictly intended for people. By the fire, which brings warmth and safety, people could safely make tools, eat and sleep, and communicate with each other. Gradually, the feeling of "home" became stronger - a place where women could take care of children and where men returned from hunting. ( White ball.)
"Fire Revolution"
Fire is life. As tools improved, man was able to penetrate areas with a less favorable climate and more efficiently use environment. However, the tools themselves did not bring drastic changes to his life: man continued to be just another predator among many. He changed his position in nature when he began to use fire to burn vegetation. This can be considered the first ecological revolution, comparable in its consequences to later ones - agricultural and industrial.
The meaning of burning the land was to get rid of forests and clear a place for meadows and pastures. Forests grow in conditions of loss of some minimum quantity precipitation. Where rainfall is less, meadows become the natural form of vegetation. Hunters are well aware that in the meadows and steppes (savannas) there is more game, which is also easier to hunt than in a dense forest. Therefore, hunting tribes usually practiced burning forests; as a result, meadows spread to those areas where more rain fell. ( White ball.)
Fire was also used to drive game, with environmental change being an added side benefit. Although hunting was later replaced by pastoralism, the practice of burning grass to maintain a treeless state continues to this day, and carefully controlled burning of forests to stimulate the growth of certain tree species and suppress others is one of the well-known techniques in modern forestry. ( white ball.)
Fire is death. Let's look at other consequences of man's use of fire to burn vegetation. There is no doubt about the reality of the onset of deserts, or "desertification". This is a formidable process in which the existing deserts of the world, such as the Sahara in Africa, are expanding their limits. In Africa, the clearing of the forest began, undoubtedly, already from the time when man mastered fire - more than 50 thousand years ago, when the first centers appeared in the east of the continent during the period of the Acheulean culture. Fire is an important tool in shifting agriculture, and although fires do occur from time to time and from natural causes, deliberately set fires by man had a much greater effect on vegetation. First of all, this is due to the fact that artificial arson was carried out in the same place more often than natural fires occurred. Even in areas with high rainfall, the forest ecosystem does not recover well after it has been disturbed over a wide area. The destruction of the forest entails a rapid deterioration in the condition of the soil, which eventually becomes so bad that the land can only be used for pasture, and then they generally turn into semi-deserts and deserts.
Let's compare two maps of Africa. One shows the main finds of ancient human sites; on the other - modern geographical zonality. An amazing pattern: people once lived on the territory of deserts, semi-deserts, dry steppes. A particularly impressive picture for the famous Sahara and Kalahari deserts. If, moreover, we take into account that fossil remains of various animals and plants, as well as traces of rivers, streams and lakes, have been found here, then there is no doubt: in the past, these now desert lands did not have an acute shortage of water. The rock paintings left by our distant ancestors testify to the abundance of flora and fauna on the site of the modern deserts of Africa. For example, the rock paintings in the Tassili region in the Sahara reflect the rise and fall of the culture of the ancient inhabitants of this region. Approximately 7000 BC they were hunters who hunted giraffes, antelopes and other animals of the savannah. Then people began to raise cattle here - the frescoes, which appeared 2000 years later, depict countless herds. The latest drawings - with images of camels - date back to about 3000-2000 BC, after which this culture disappeared under the onslaught of conquerors. Let us accept as a hypothesis: the landscapes of the Sahara at the end of the Stone Age were subjected to serious ecological pressure from hunters and gatherers. According to biogeographer I. Schmithuizen, “natural fires are rarely observed in the grassy spaces of the periodically dry tropics... Here, the cause of fires is always a person who, partly for the sake of improving the quality of pastures, and partly involuntarily causes the grass stand to burn out, which annually occurs over vast areas and determines the nature vegetation in these areas. With the exception of flooded savannahs, all other savannahs ... arose under the direct influence of man. Conclusion: the famous deserts of Africa - the Sahara and the Kalahari - are of anthropogenic origin ( Black ball.)
Judges. Over the past 150 thousand years, the territory of the Sahara and Kalahari deserts has repeatedly decreased and increased due to climate change, without human intervention.
Fire is death. Aridization of the climate of North Africa since 5000 BC was largely provoked and accelerated by human economic activity.
Let us turn to events that took place in another part of the world. Dutch navigator A.Ya. Tasman and his team, the first Europeans to see the shores of the island called Tasmania, did not meet the natives, but drew attention to the clouds of smoke rising in different places above the forest. Subsequent explorers of the island constantly observed forest fires, an abundance of bonfires bred by the natives. And although the Tasmanians were engaged in hunting, fishing, gathering, the main "lever" with which they "turned over" their land - they radically rebuilt landscapes - was fire. “The ecological effect of these systematic fires,” writes V.R. Cabo - very large. Vast areas of Tasmania have undergone a change of vegetation; there have been changes in the nature of the soil, the climate has changed. The Tasmanians used fire not only to hunt animals, but perhaps even on a larger scale - to increase the area of open spaces and increase the fertility of pastures on which wild animals grazed. It was, one might say, a peculiar form of primitive animal husbandry with the help of "pyrogenic processing" of hunting grounds.
Conclusion: the use of fire by Tasmanian natives led to a change in flora and fauna and, as a result, had a negative impact on the ecosystem of the island as a whole. ( Black ball.)
In a similar way, a person mastered Australia. Travelers and missionaries of the past often referred to the widespread use of fire by the Australian Aborigines for a variety of purposes. The hunting tribes of Australia, with whom the Europeans met, were constantly nomadic. According to tentative estimates, each tribe, or rather, each nomadic group annually burned about 100 km2 of forests, savannahs, steppes - purposefully or involuntarily. Thousands of such groups over 20-30 millennia could repeatedly - dozens of times! - burn vegetation throughout the continent. This is how pyrogenic landscapes were created over vast expanses. Of course, they were not formed everywhere, but in territories with a certain climate and vegetation cover. But the general nature of the changes in such active exploitation is expressed in the depletion of biological resources and desertification.
Conclusion: modern deserts and semi-deserts of Australia are of anthropogenic origin. ( black ball.)
Judges. The conclusion is made very sharply, unsubstantiated.
Fire is death. Unlike Tasmania, the climate of Australia is drier, with 200–300 mm of precipitation per year in the central regions. The situation is complicated by constant deviations from the average value: sometimes 3–4 times less, sometimes twice as much. In dry years or seasons, a feedback mechanism began to operate: fires caused especially severe damage to forest areas, and the disappearance of forests - soil moisture stabilizers - caused soil drying and erosion. Forest-steppe, steppe and semi-steppe territories have existed in Australia for a long time, even before the appearance of man. However, the activities of nomadic groups of hunters and gatherers eventually led to a reduction total area forests, increase in deserted spaces. According to the English researcher W. Chesling, for a long time who lived among the Australian tribes of the Yulengors, the latter set fire to the forest during the hunt. By October, when the wind subsides, the fires have time to destroy all the humus. Now the burning sun is completing its destructive work - the country is turning into a pile of ashes. In December the wind changes direction; highly saturated with moisture, it blows from the north-west, streams of rain flood the country ... Loose soil, sand, ash, humus - everything is washed into the swamps or carried away to the sea. How deep such transformations can be can be judged, in particular, by the testimony of the Australian scientist Ch. Moundford, who described the pyrogenic landscapes of Central Australia: when the first white people reached the mountains of Manna, this huge depression was full of water, in which hundreds of ducks and other waterfowl were splashing.
About 6–10 millennia ago, in a completely different part of the globe, in the Arctic, on the territory of Yakutia, Taimyr, Kamchatka, Chukotka, Alaska, the so-called Sumnaginskaya culture of the late Paleolithic spread widely. Such a significant distribution in high latitudes is due to a favorable climate. The boundary between forest and tundra was shifted 300–400 km to the north. The people of the Sumnagin culture, of course, influenced the landscapes of the Arctic. Their main weapon was fire. Trees and shrubs in the polar regions grow very slowly and regenerate poorly. The destruction of the vegetation cover during burnings and fires caused a chain of processes that ultimately led to very serious consequences.
After the destruction of vegetation, the soil froze faster and deeper in winter, but it also thawed faster and deeper in summer. In the forest-tundra, the second process is often decisive. Intensification of summer thawing often leads to solifluction - sliding of thawed soil on slopes, and in the presence of underground ice - to a very wide development of thermokarst. In winter, snow blown by the wind accumulates in subsidence funnels, which makes it difficult to freeze, and in summer melt water stimulates thawing and a further increase in the size of the funnel. There are many lakes and swamps. Even in very severe winters, the ice thickness in the lakes does not exceed 2–2.5 m. Therefore, the bottom sediments of reservoirs with a greater depth remain in a non-frozen state, and if the width of the lake is more than twice the thickness of the permafrost, a through talik appears under it. But the gradual accumulation of the peaty horizon in the swamps more and more slows down the summer thawing, and the permafrost begins to win back its lost positions.
The destruction of the forest near the northern border of the taiga zone, where the thickness of the snow cover does not reach 20 cm, leads to a cooling of the soil, and with large snow thicknesses, to its warming. Accordingly, permafrost reacts to these changes. What is it connected with? The fact is that snow cover affects temperature regime underlying soil in two ways. On the one hand, it has a high reflectivity and reduces the influx of radiant energy. On the other hand, snow is a good thermal insulator, which means it holds back the winter cooling of the soil. Therefore, snow cover of different thickness has opposite effects. With a thin cover, the dominant role belongs to the reflection of heat. With a more significant thickness of the snow cover, its heat-insulating properties begin to play a decisive role. Finally, with even greater thickness, snow again turns out to be a cooler (if we talk about the average annual temperature), because it takes longer to melt in summer.
Thus, under different conditions, human activity can lead to different results: as a result of fires, permafrost can degrade, or areas of pyrogenic tundra with colder soils appear.
Conclusion: The formation of anthropogenic (pyrogenic) tundras began as early as the time of the Sumnaga culture (6–10 thousand years ago). Human activity contributed to the expansion of the tundra zone and the retreat to the south of the northern border of the taiga. The modern boundaries of the tundra were formed under the influence of anthropogenic impact. ( Black ball.)
(When studying changes in biota in the geological past, it is important to place the emphasis correctly, taking into account the influence of both external (climate, the influence of large mammals) and internal (the stage of development of the biome, as a thermodynamic system) factors that stimulate these changes. and the Atlantic periods - 10,000–5,000 years ago) there was an active advance of the forest both to the north and south of the current boundaries of the forest zone. brought to life the reverse process - the aridization of the southern part of the forest zone and the gradual retreat of the forest to the south in the north. Now, by the way, against the background of modern climate warming, the forest is again moving northward (the attack of the taiga on the tundra), despite the intense anthropogenic load in this region.Human impact on vegetation, which was similar throughout the early and middle years Holocene, only provoked these processes only in the period when unfavorable climatic conditions formed for their occurrence. Therefore, one cannot speak so categorically about the anthropogenic origin of the tundra. With permafrost, everything is also not quite the same. It suffices to point out, for example, the fact that in the taiga zone of Eastern Siberia, on the permafrost layer starting from a depth of 15–30 cm, larch forests from Larix davurica grow well. - Approx. ed.)
Fire and metallurgical production
Fire is life. The Age of Metal is the next page in the history of human culture after the Neolithic. The oldest traces of bronze in Mesopotamia and Egypt date back to the 4th millennium BC. e. The beginning of iron ore smelting dates back to 1300 BC. e. If earlier the material from which the tool is made is wood, stone, bone, etc. - was something given, ready, now the process of making a tool was preceded by the process of making a material for this tool - a material with new properties. Mining is impossible without the use of fire. ( white ball.)
Fire is death. The main causes of technogenic atmospheric pollution are the combustion of natural fuel and metallurgical production. If in the XIX and early XX centuries. Since the products of combustion of coal and liquid fuel entering the environment were almost completely assimilated by the vegetation of the Earth, at present the content of harmful man-made emissions in the atmosphere is steadily increasing. A large amount of pollutants enter the air from furnaces, furnaces, exhaust pipes of cars. Among them are sulfur dioxide, nitrogen oxides, carbon monoxide, lead compounds, various hydrocarbons - acetylene, ethylene, methane, propane, toluene, benzopyrene, etc. Together with water droplets, they form a poisonous fog - smog, which has a harmful effect on the human body, on vegetation cities. Liquid and solid particles (dust) suspended in the air reduce the amount of solar radiation reaching the Earth's surface. So, in big cities, solar radiation decreases by 15%, ultraviolet radiation - by 30% (and in the winter months it can completely disappear).
Billions of tons of carbon dioxide are released into the atmosphere every year as a result of burning fossil fuels. Approximately half of the carbon dioxide produced by the combustion of fossil fuels is absorbed by the ocean and green plants, while half remains in the air. The content of CO 2 in the atmosphere is gradually increasing and has increased by more than 10% over the past 100 years. Carbon dioxide prevents the transfer of heat into outer space, which leads to the so-called "greenhouse effect". Changes in the content of CO 2 in the atmosphere greatly affect the Earth's climate. All this is a consequence of the development of fire by man. ( black ball.)
Summing up the lesson
The judges count the number of black and white balls. There are more whites. Discussion of the obtained results. Students are free to express their opinion.
Teacher. Occasional use and possibly maintenance primitive people ignited fire began about 1–0.5 million years ago. Approximately 50 thousand years ago, man himself learned how to make fire from sparks when a flint strikes flint or with the help of friction. About 20 thousand years ago, energy consumption averaged 10 thousand kJ per person per day, and at present, economically developed countries– over 1 million kJ. Even more striking is the growth in the total energy consumption of all mankind during this time - 10 million times. It is due to this million-fold increase in the use by man of the reserves of solar energy, preserved in organic fuel, that the entire complex of modern life support for mankind has been created and is functioning.
If, many thousands of years ago, none of our distant ancestors, warming themselves by a tree set on fire by lightning, had thought of throwing a few new branches into a dying fire, we would still live in caves.
In ecological terms, burning firewood in a primitive fire is the very first and therefore the most significant step of mankind towards the search for new, more and more efficient energy carriers, which ultimately led to an unprecedented increase in the pressure of one species - man - on the nature of the entire planet.
Therefore, do not forget about the black balls on the scales. Changes in landscapes, climate on our planet - all these are the detrimental consequences of mastering fire. Sometimes humanity resembles a child who has found a box of matches and, secretly from adults, indulges in early spring on a sunny hillock, setting fire to last year's dry grass. Tongues of flame, at first barely noticeable and harmless, fanned by a spring breeze, in seconds turn into a roaring monster, sweeping away a haystack, outbuildings, and a house in which a child lives in its path. The house where we live.
Remember this. The future of our planet belongs to you, the younger generation.
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Application
J. Roni Sr.
"FIGHT FOR FIRE"death of fire
In the impenetrable night, the Ulamry fled, mad with suffering and fatigue; all their efforts were in vain before the misfortune that befell them: the fire was dead! They supported him in three cages. According to the custom of the tribe, four women and two warriors fed him day and night.
Even in the most Hard times they supported life in it, protected it from bad weather and floods, carried it through rivers and swamps; bluish by daylight and crimson by night, he never parted from them. His mighty face put lions, cave and gray bears, mammoth, tiger and leopard to flight. His red teeth protected man from the vast and terrible world; all joys lived only around him. He extracted delicious smells from meat, hardened the ends of horns, made stones crack, he encouraged people in dense forests, in endless savannah, in the depths of caves. This fire was the father, the guardian, the savior; when he broke out of the cage and devoured the trees, he became more cruel and wild than mammoths.
And now he's dead! The enemy destroyed two cages; in the third, which survived during the flight, the fire weakened, grew pale and gradually decreased. He was so weak that he could not even eat swamp grasses; it trembled like a sick animal, turning into a small insect of a reddish color, and every breath of wind threatened to extinguish it ... then it disappeared altogether ... The Ulamry fled, orphaned, into the autumn night. There were no stars. The heavy sky descended over the heavy waters; the plants stretched their cold stalks over the fugitives, and all that was heard was the rustling of the reptiles. Men, women, children were consumed by darkness. Listening to the voices of their leaders, they tried to move on dry and hard land, fording the streams and swamps they encountered. Three generations have known this path. At dawn they came to the savannah. Cold light seeped through the chalk layers of clouds. The wind swirled on the oily waters like mountain resin. Algae swelled like pustules, petrified lizards lay curled up among the water lilies. A heron sat on a withered tree. Finally, in a red haze, a savannah unfolded with plants trembling from the cold. The people perked up and, having passed through thickets of reeds, they finally found themselves among the grasses, on solid ground. But then the feverish excitement subsided, people lay down on the ground, froze in immobility; women, more enduring than men, who lost their children in the swamps, howled like she-wolves, those who saved their babies lifted them up to the clouds. When dawn broke, Faum counted his tribe with his fingers and branches. Each branch corresponded to the number of fingers on both hands. Remained: four branches of warriors, more than six branches of women, about three branches of children, several old men.
Old Gong said that one man out of five, one woman out of three, and one child out of a whole branch survived.
The Ulamr felt the enormity of the misfortune. They realized that their offspring were threatened with death. The forces of nature became more and more formidable. People will roam the earth, miserable and naked.
To be continued
* The lesson can be conducted while studying the topic “The Origin of Man” in the course “General Biology. Grade 11", as well as when studying the topic "Anthropogenic impact of man on nature" in the course "Ecology"
The significance of fire in the life of mankind at all stages of its existence deserves a separate discussion. For half a million years now, fire has become an indispensable attribute of human life. In those infinitely distant times, its practical significance was enormous. Fire is the most reliable defense against predators. Fire is a source of heat, which made it possible to fry meat, bake fruits and roots. And, finally, fire is an important means of processing wooden tools (both spears and clubs began to be fired for strength three hundred thousand years ago)...
However, he played no less a role in strengthening purely human, social relations. The sacred fire is a symbol of the unity of the collective, the source of its strength, a wayward friend and guardian. He must be loved and protected and be careful with him, so that his violent power does not turn against the person himself. "The warmth of the hearth" - how far into the depths of human history this concept goes! It is familiar to all of us, although our homes have long been heated not by hearths, but by central heating batteries and electrical appliances. But, perhaps, that craving for fire, for a living flame, which forces modern people to build fireplaces in their apartments, turn off electricity and light candles on fire, leads to even deeper antiquity. festive table gather around campfires.
By the time the Upper Paleolithic tribes of mammoth hunters appeared, mankind had long known fire and was fluent in the main methods of its production. Judging by ethnographic data, there were three such methods: “fire plow”, “fire saw” and “fire drill”.
The first method is the simplest and fastest, although it requires a lot of effort: a wooden plank lying on the ground is driven with strong pressure with the end of a wooden stick - as if “plowed”. A narrow groove is formed, and in it - wood powder and thin chips, which, from heating during friction, begin to smolder. A flammable tinder is connected to it and a fire is fanned. This method is relatively uncommon; most often it was used on the islands of Polynesia (Charles Darwin learned it from the inhabitants of the island of Tahiti). Occasionally it was used by the Australians, the Tasmanians, the Papuans, and some backward tribes of India and Central Africa, although elsewhere preference was given to other methods.
The “fire saw” has many varieties, but they all boil down to one principle: a soft, dry piece of wood lying on the ground is, as it were, “sawed” across the fibers with a piece of hard wood. Interestingly, the Australians, who quite often resort to this method, use a wooden shield as a base, and a spear thrower as a saw. Further, everything happened in the same way as during “plowing” (only there the work was carried out along the fibers): wood powder was formed and ignited. Often, with this method, tinder was placed in a previously prepared slot. Sometimes, instead of a wooden plank, a flexible vegetable cord was used as a "saw". This method has been used in Australia, New Guinea, the Philippine Islands, Indonesia, and parts of India and West Africa.
Drilling is the most common method of making fire. It consists of the following. A small plank with a pre-hollowed recess is placed on the ground and clamped with the soles of the feet. The end of a hard stick is inserted into the recess, which is quickly rotated between the palms, while pressing down. This is done so skillfully that the hands, involuntarily sliding down, periodically return to their original position, and the rotation does not stop and does not slow down. After a few minutes, smoke appears from the recess, and then a smoldering light, which is fanned with tinder. This method is widespread among almost all backward peoples of the Earth. In an improved form, a stop is attached to the rod from above, and from the sides - a belt, which is alternately pulled by the ends, causing the drill to rotate. By attaching a small bow to the ends of such a belt, we get the simplest mechanism, quite common in primitive times: a bow drill. Not every modern person is able to make fire by rotating a wand between the palms: great skill is needed here, even when the source materials are well chosen. But with the help of a bow drill, this, apparently, is available to many ... Try it yourself, just remember: the plank should be made of soft and dry wood, and the stick should be made of hard wood.
But what about striking fire by striking flint on flint? It would seem that, observing the sparks that occur when cracking flint, it was easier for people to think of such a way to get fire than to invent rather complex operations with wood. Some scientists think so. B. F. Porshnev, for example, believed that the carving of fire, which arose in the process of making stone tools, preceded the methods of obtaining it by friction. The English archaeologist C. P. Oakley adhered to the same point of view. However, ethnographic evidence suggests otherwise.
The most backward peoples in the 19th century produced fire everywhere by friction, while striking fire (especially by striking flint on flint) was very poorly spread among them. On the other hand, peoples at a higher stage of development produced fire mainly by carving (flint on iron or iron ore - pyrite). Sometimes they also used friction - but only for ritual, cult purposes. Yes, and experiments show that although a spark is constantly formed when flint strikes flint, it is quite difficult to “turn” it into fire, while kindling a flame by friction is possible, with some effort, even for modern man.
It is possible, however, that in some cases people actually learned how to strike fire first, and only then began to produce it by friction. In at least one of the South American Indian tribes, the term for making fire comes from the word "hewing with a blow." This clearly speaks of some old (perhaps really original!), And later forgotten tradition. I say: "forgotten" - because here, until recently, the main method of making fire was again friction. However, this is the only exception.
Mammoth hunters' hearths
Primitive peoples are distinguished by their great skill in keeping and maintaining fire. Here is what, for example, the well-known Russian ethnographer N. A. Butinov writes about Australians: “Australians are very skillful in arranging and maintaining a fire, it burns evenly, without giving a large and too bright flame. They laugh at the European colonists, who make fires so large that it is dangerous to approach them, and they are of little use, and they do not know how to maintain them for a long time. On the contrary, by his small fire, the Australian sleeps peacefully all night, and bakes and fries food on it.
There is no doubt that people have mastered this art for a very long time. Evidence of this is the remains of bonfires and hearths found by archaeologists. Particularly interesting and diverse are the foci in settlements dating from the second half of the Upper Paleolithic, primarily in sites with long-term dwellings. Here, along with simple hearths, which are bowl-shaped depressions filled with ash and coal, there are much more complex structures. The lining of hearths with stones has been used for a long time; it is also known in some centers of the Willendorf-Kostenkovskaya culture of mammoth hunters (Zaraisk site, upper cultural layer). In other monuments of this culture, in addition to lining, clay was used. In the same place where ceramic figurines of animals were made (Dolni Vestonice, Kostenki 1/1), individual hearths with clay coating resembled the simplest stoves.
In close proximity to many Upper Paleolithic hearths, small pits dug out in the ground. Some of them were used for baking food, others served as supports for the posts (they sometimes contain vertically protruding bones that wedged these posts). Now we install a crossbar on such supports, on which we hang a pot to boil tea or cook fish soup, and then they could serve as the basis for skewers on which meat was fried.
Grooves were dug at the base of some hearths. Sometimes such a groove went away from the hearth to the side. What for? Petersburg archaeologist Pavel Iosifovich Boriskovsky, who found such a hearth during excavations at the Kostenki 19 site, which existed about 20 thousand years ago and was also left by mammoth hunters, suggested that air entered the hearth through such a groove, which intensified the combustion process. An experiment was set up: two hearths were dug side by side: with and without a groove. Indeed, in the first of them, the flame burned much better.
What is the meaning of fire in human life, you will learn from this article.
The meaning of fire in human life
Fire has already entered our lives so much that we cannot imagine ourselves without it. But if you think about it, so globally, what gives us fire?
- Warm to cold
With the help of fire, a person can warm himself in a frosty winter, or a cold night. The heating of a house, dwelling, whatever it was - whether it was a cave, a tent or a house with a stove, was always carried out with the help of fire. Heating pipes, electric heating, batteries are the blessings of our civilization. But in the Stone Age the importance of fire in the life of ancient people was invaluable. After all, he saved lives, giving warmth and scaring off enemies.
2. Fire is dry clothes
Being in close harmony with nature, a person spends a lot of his free time outdoors. If suddenly it starts to rain, then it is logical that the clothes will get wet. Also, contact with the aquatic environment, namely lakes, rivers, seas, can also make our clothes wet. Staying in such clothes is fraught with a cold, and a very strong one. You can also dry clothes in the wind, if it is summer time outside, or with the help of fire, which is more likely.
3. Fire is cooked food
Can you, having overcome yourself, eat raw or live fish? What about raw poultry, like partridge or chicken? You may have to eat something raw in the event that you do not have a fire. Therefore, it ensures the availability of delicious food.
4. Fire is light
Among other things, fire can be used as a source of illumination in the dark.
5. Fire is a reliable defense against predators
It is difficult to imagine an animal that would not be afraid of fire, especially if you take a burning branch and stick it right in the face of the beast. As a rule, the flight will be instantaneous.
6. Fire is a signaling device
Throughout human history, fire has often been used as a means of communication. In the dark, the fire can be seen several kilometers away, and the smoke from the fire is visible far in the daytime. It was customary to light signal fires if an enemy attacked.
We hope that from this article you have learned how important fire is for a person.
It is difficult to imagine the life of modern man without the use of fire. Thanks to him, people live in comfortable conditions - in warm houses, lit rooms, eat delicious food and daily use objects created with the help of flame. The process of extraction and subjugation of fire was very complex and long. Thanks to ancient man we can use this resource.
The role of fire in the life of primitive man
One and a half million years ago, man was able to subdue fire. Ancient man was able to create lighting, a warm home, delicious food and protection from predators.
The taming of fire by man is a rather lengthy process. According to legend, the first fire that a person could use was heavenly fire. The phoenix bird, Prometheus, Hephaestus, the god Agni, the firebird - they were gods and creatures that bring fire to people. Man deified natural phenomena - lightning and volcanic eruptions. He made fire by lighting torches from other, natural fires. The first attempts to make fire gave a person the opportunity to keep warm in winter time, illuminate the territory at night and defend against the constant attacks of predatory animals.
After a long use of natural fire, a person needed to independently extract this resource, because natural fire was not always available.
The first way to produce a flame was to strike a spark. A man has been watching for a long time how the collision of some objects causes a small spark, and decided to find a use for it. For this process, people had special devices made of prismatic stones, which were fires. The man struck at the fires with rough prismatic knives, causing a spark. Later, fire was produced in a slightly different way - they used flint and steel. Moss and fluff were set on fire with flammable sparks.
Friction was another way of producing fire. People quickly rotated dry branches and sticks inserted into a tree hole between their palms. This method of obtaining a flame was used by the peoples of Australia, Oceania, Indonesia, in the tribes of Kukukuku and Mbowamba.
Later, man learned to make fire by drilling with a bow. This method made life easier for the ancient man - he no longer had to put in a lot of effort, rotating the stick with his palms. The ignited hearth could be used for 15 minutes. From it, people set fire to thin birch bark, dry moss, tow and sawdust.
Thus, fire played a dominant role in the development of mankind. In addition to being a source of light, warmth and protection, it also affected the intellectual development of ancient people.
Thanks to the use of fire, a person had a need and the possibility of constant activity - it had to be mined and maintained. At the same time, it was necessary to ensure that it did not spread to the houses and was not extinguished by a sudden downpour. It was at this point that the division of labor between men and women began to take shape.
Fire served as an indispensable tool in the manufacture and processing of weapons and utensils. And most importantly - he gave man the opportunity to develop new lands.
The role of fire in the life of modern man
The life of a modern person cannot be imagined without fire. Almost everything that people use is based on fire. Thanks to him, the houses are warm and light. Man daily uses the energy of fire in everyday life. People cook, wash, clean. Light, electricity, heating and gas - all this would not have happened without a little spark.
Fire energy is also used in various enterprises. In order to make a car, an airplane, a diesel locomotive and an ordinary plug, metal is needed. It is with the help of fire that a person mines it - melts the ore.
An ordinary lighter burns using a slightly modified method of the ancient people - improved fire. Gas lighters use a mechanical spark, while electric lighters use an electric spark.
Fire is used in almost every human activity - ceramic production, metallurgy, glassmaking, steam engines, chemical industry, transport and nuclear energy.
Goals: show the role of fire in human life, both positive and negative; introduce children to the profession of a firefighter; to teach children to appreciate the courage and heroism of people in this profession; test students' knowledge of fire safety rules; to convince of the inadmissibility of jokes with calling the fire brigade; encourage creativity; make a memo on how to behave in case of fire.
Equipment: illustrations for the legend of Prometheus or cartoon, fire safety posters.
Class hour progress
A conversation about the history of mastering fire
Mystery
What in the world has no measure, no weight, no price?
Without arms, without legs, but eats everything? (Fire.)
The discovery of a method for making fire was a significant victory for man over nature. This is what is said about the meaning of fire in the legend of Prometheus.
In ancient times, when Zeus ruled the whole world, people who had just settled on earth were weak, powerless, shy. They could neither think nor understand what they saw around them. With horror they looked at the thunderclouds, the scorching sun, the endless sea and high mountains. From everything that frightened them, people hid in caves. At that time they had neither housing nor a family hearth: people did not cook food, did not warm themselves near the fire. And it was such a miserable existence.
The titan Prometheus took pity on people with his big heart and boldly violated the ban of Zeus: not to give fire to people. Having made his way to the palace, the titan took a small spark of fire and, hiding it in an empty reed stalk, brought it to people on earth. Since then, the bright lights of fires on the ground have shone. Whole families gathered around them, fried meat, warmed themselves, danced. Now people have healed more cheerfully and more friendly, and the titan Prometheus sincerely rejoiced at this. He taught people to tame fire, to melt copper, to forge weapons. Thanks to Prometheus, people learned to think and, probably, for the first time felt like people.
Fire has become a reliable companion and helper of people. It is difficult to imagine such a branch of human activity, where fire would not be used. Help me: name the areas of application of fire. (Cooking, internal combustion engines, metal smelting, glass and building materials manufacturing, pottery firing, thermal power plants, etc.)
It is possible to list for a long time how fire helps us all both at home and at work, but we must always remember that careless handling of fire can lead to trouble. Let's remember Samuil Marshak's poem "Fire".
(Students act out the poem.)
Mother went to the market
Daughter Lena said:
"The stove, Lenochka, don't touch it,
It burns, Lenochka, fire!”
Only mother came down from the porch,
Lena sat down in front of the stove.
He looks into the red firebox,
And in the furnace the fire is buzzing:
“Now there is not enough space in the oven,
There was nowhere to roam.
Mom, Lenochka, do not believe
Open the door wider."
Lena opened the door,
The fire jumped from the log.
Burned the floor in front of the stove
Climb up the tablecloth on the table,
Ran over the chairs with a bang,
Crawled up the curtains
The walls were covered in smoke
Licking the floor and ceiling...
And now some statistics.
There are about five million fires in the world every year.
Every hour, one person dies in the fire, two are injured and burned.
Every third victim is a child.
From horse-drawn carts with manual fire pumps to powerful modern means extinguishing fires - this is the way of development of fire protection. Today this special service is one of the most mobile.
They are afraid of the steppe, mountain expanses
His hot, merciless paws.
But there are people for whom
He is like a tamed one - obedient, quiet and weak.
They will nail him to the ground, extinguish him,
In a burning house, fearless, they will enter.
For the lives of others, they, without a doubt,
They will give their lives.
Such people fighting with fire,
We call our firefighters!
Every hour on our planet there are seven hundred fires and sunburns. There are more than five million of them a year. Losses from fires can be compared with the losses of small wars of the twentieth century. Out of ten fires, nine occur through the fault of a person, every fifth fire is due to childish pranks with fire. Our firefighters are constantly fighting with them.
The accident at the Chernobyl nuclear power plant in 1986 showed that firefighters with honor passed a serious maturity test, averted misfortune from hundreds of thousands of people, while showing heroism and courage. The first to the reactors, a few seconds later, on alarm, were firefighters from the nuclear power plant guard, headed by the head of the guard, Pravik. His squad was the first to step into the line of fire. Of all the possible solutions, Vladimir Pravik chose the most correct: he sent his detachment to the roof of the engine room. They are heroes! What they did is a feat! The fact is that it was in this hall that all the turbines were located, numerous cables of the high-voltage line went through it, which from the fire could turn into a Fickford cord. Could they retreat? Could they not do what they did and save their lives? Yes, they could. They could temporarily retreat until reinforcements arrived. But no one thought about it. These were people with a heightened sense of responsibility, people who took an oath. And they stepped into the raging flame, into the lethal radiation, not by order of the commander, but by the law of conscience. They rushed to save the station and people, not thinking about their lives. They were clearly aware of the danger, but like real warriors they did not spare themselves.
(The phone rings.)
- “My phone rang ...” Which of you from childhood is not familiar with these lines of Korney Ivanovich Chukovsky? What are these nursery rhymes about? About games with the phone. Now raise your hands, those who at least once called and joked on the phone. Now admit it, jokers, who called the fire brigade for the neighbors? Do you know why such actions are unacceptable? (Wasteless expenditure of gasoline. The fire truck wears out. But most importantly: at this time, a fire can really break out somewhere and someone will need help.)
I know that you are competent people in matters of fire safety. Do you want to confirm it? Then I bring to your attention a quiz.
Questions(they were prepared and asked by the students themselves):
1. What things are allowed to be hung on electric wires?
2. What kind of nails can be driven between wires?
3. What kind of fabric can wrap a light bulb?
4. What kind of wallpaper is allowed to paste over the wires?
5. On which knife switch can you hang clothes?
6. In which hand should a car driver hold a cigarette while driving over a wooden bridge?
7. On which side should a fire be lit in windy weather?
8. Why is the iron lining nailed to the floor near the stove door?
(The teacher notes the most attentive, most resourceful, most literate of the participants in the quiz.)
And now, guys, I invite you to cooperate. Let's all create a memo "How to behave in case of fire" together.
Children and the teacher make a memo. The pupils stick the prepared memo in the diary.
Puzzles
An ember fell on the floor,
The wooden floor is on fire.
Don't look, don't wait, don't stand
And fill it with ... (water).
If younger sisters
Lighting matches at home
What should you do?
Those matches right away ... (take away).
Where is garbage stored?
Or just different rubbish
Will have to make an effort
Put things in order there.
Broom, shovel taken
And quickly everything ... (removed).
The red beast is sitting in the oven,
The red beast is angry at everyone.
He eats firewood out of anger
A whole hour, maybe two.
Don't touch him with your hand
Bites the whole palm ... (fire).
What happens if the birds
Do you light matches at home? (Fire.)
A midge flew - an aspen leg.
She sat on a stack - all the hay burned down. (Match.)
Back then forward
The steamer is sailing,
Stop - grief
Pierces the sea. (Iron.)
Hissing and angry
Afraid of water.
With tongue, not barking.
No teeth, but bites. (Fire.)
We were pines and firs
And now we’re strumming stuffed into the box.
We were the pride of the taiga -
And now her enemies. (Matches.)
In a small barn
There are a hundred fires. (Matches.)
Chew - do not chew,
And I eat everything. (Fire.)
Like a sparrow's leg,
The box slides down the wall.
Slips - and carves out the fire,
When it burns, don't touch it
Playing with her is a bad habit.
Dangerous toy... (match).
Four suns in grandma's kitchen
Four suns burned and went out.
Shchi, compote, pancakes are ready -
Until tomorrow the sun is not needed. (Gas stove.)
Remember!
To avoid fires
Everyone needs to know the rules.
Of course, there are a lot of them -
Let's learn at least five.
Near the house and barn
Don't you dare light a fire!
Might be a big problem
For buildings and people.
And in the forest the fire is dangerous -
For trees, birds, animals.
The forest will be beautiful for everyone
Without fires and coals.
So that the fire does not run away
So that he knows his place
You create a barrier for him:
From stones, earth fence.
Leaving, cover with earth
Or fill it with water.
For wheat to grow
It takes a lot of work -
You don't light a fire
Where the harvest is.
Suddenly the clothes caught fire -
Immediately on the floor you fell
Roll on the floor right away
Turn into a blanket.
It's time for everyone to understand:
Matches are not a game for children!
Let it be clear to adults...
It's dangerous to play with fire!
A big fire or fire is a huge monster that devours everything around with its fiery tongue. This huge tongue eats up favorite toys, dresses, houses, and even entire streets.
As a rule, children are afraid of fire. What do you think, is it possible to make the fire not scary at all? Yes, you certainly may! To do this, you need to learn how to manage your fear. To begin with, let everyone say to themselves: “I am strong. I am not afraid of fire. I can control fire. I can prevent a fire." And in order to prevent a fire, you need to know well the rules for using objects from which it can arise.
1. What, barely touching, turns a house into firewood? (Fire.)
2. On the roof - with a pillar, in the hut - with a tablecloth. (Smoke.)
3. This is a cramped, cramped house: One hundred sisters huddle in it. And any of the sisters
Might flare up like a fire! (A box of matches.)
4. Hisses and gets angry, afraid of water; with tongue instead of barking; without teeth, but bites. (Fire.)
5. An electric ship floats - then back, then forward. (Iron.)
6. A hundred fires are kept in a small barn. (A box of matches.)
7. Everything eats - does not eat up, but drinks - dies. (Fire.)
8. The red bull is standing, trembling, the black one is running to the sky. (Fire and smoke.)
9. Small, remote, but brings big trouble. (Spark.)
10. The red cow ate all the straw. (Fire.)
11. I saw smoke - do not yawn, call us soon! (Firefighters.)
12. You won’t get rid of fire from a little me. (Spark.)
13. Where people are careless with fire, it will definitely be. (Fire.)
14. On the table, in a cap and in a glass vial, a friend settled - a cheerful light. (Bulb.)
memo
If you see a fire, you must report the following information by calling 01:
2. Object (apartment, warehouse, school).
3. What is on fire (what exactly is on fire in the apartment, school).
4. House number.
5. Entrance number.
6. Apartment number.
7. Floor. How many floors are in the building.
8. Is there a danger to people.
9. Surname.
10. Phone.
After carefully studying the memo (30 seconds), everyone should make a “call to the firefighters”. The work is done in pairs. Listen to 2-3 pairs.
Summarizing
Complete the phrase: "Now I know that..."
Additional material for the teacher
Brief history of fire fighting
♦ In the "Sudebnik" of Ivan III, introduced in 1498, it is said about the Kurts: "Do not give the lighter of the stomach, execute him with the death penalty."
♦ Since 1689, Peter the Great ordered fires to be extinguished by the forces of Moscow archers, sotsk elders and townspeople.
♦ In 1803, Alexander I signed a decree on the organization of fire protection in St. Petersburg.
♦ The first fire brigade in Kyiv was organized in 1841, it consisted of 25 people.
♦ On April 17, 1918, the Decree “On State Measures to Fight Fire” was signed. This day became the day of the formation of the fire department.
dramatization
Zero-one - the phone rang,
Someone's cry was brought by wires,
Someone's cry caught the microphone -
It means that trouble happened somewhere ... (Fire and Matches come out.)
I am fire, I am a friend of the guys.
But when they mess with me
Then I become an enemy
And I burn everything around. (Whirls around the stage.)
1st match.
Man's friend is fire,
Just don't touch him!
If you mess around
That trouble can not be avoided
Don't get sick of the fire!
2nd match.
Know that in anger he is angry:
Spare nothing!
Can destroy a school
Grain field, your home
And the house is all around.
And up to the sky,
Spread to the forest.
3rd match.
Fire is strong - it can burn a village.
He is merciless, angry, assertive, rude.
And he will destroy hundred-year-old trees
Faster than a skilled lumberjack.
4th match.
And where he goes.
The forest is burning, the whole is burning to the ground.
No wonder there is a saying among the people:
"Fear like fire."
5th match.
Dying in the fire
Even people sometimes.
Always remember this!
Always remember this!
Remember!
(May be given as a handout to each child.)
For fun, for play
Do not take matches in your hands.
A box of matches is small,
But much can do evil.
Don't light the fire yourself
And don't let others
Even a little spark
Not far from the fire.
Do not take heat from the stove -
After all, he's a fire.
Coal, though small,
But dangerous, like a match.
Gas in the kitchen, is it a vacuum cleaner,
TV and iron
Let it include only an adult -
Our trusted senior friend.
If trouble befalls,
What then shall we do?
Never get lost
Act skillfully.
If the fire is weak, hurry
You fill it with water.
If the phone is close
And it's available to you
