..... Click the link for more information. as seen in light, flame flame, phenomenon associated with the chemical reaction of a gas that has been heated above its kindling temperature with some other gas, usually atmospheric oxygen (see combustion).
..... Click the link for more information. , and heat; it is one of the basic tools of human culture. In ancient Greece and later, fire was considered one of the four basic elements, a substance from which all things were composed. Its great importance to humans, the mystery of its powers, and its seeming capriciousness have made fire divine or sacred to many peoples. Fire as a god is a characteristic feature of Zoroastrianism, in which, as in many sun-worshiping religions, fire is considered the earthly representative or type of the sun. The belief that fire is sacred is widespread in mythology, and such beliefs have survived in some highly developed cultures. The connection between the Greek colony and the metropolis was the fire kindled in the colony from a brand brought from the mother city's fire. The most carefully preserved cult in Rome was that of Vesta, goddess of the hearth, and her virgins guarded the holy fire. One of the greatest Greek myths is the story of Prometheus Prometheus , in Greek mythology, great benefactor of mankind. He was the son of the Titan Iapetus and of Clymene or Themis. Because he foresaw the defeat of the Titans by the Olympians he sided with Zeus and thus was spared the punishment of the other Titans.
..... Click the link for more information. , the fire bringer. The theft of fire is a common element in the myths of many other cultures. The ramifications of the human ideas about fire are tremendously complex, extending as they do into the concepts about light and the heavens.
Bibliography
See J. G. Frazer, Myths of the Origins of Fire (1930, repr. 1971); G. Bachelard, Psychoanalysis of Fire (tr. 1964).
fire
Rapid burning of combustible material, producing heat and usually accompanied by flame. For eons, lightning was the only source of fire. The earliest controlled use of fire seems to date to c. 1,420,000 years ago, but not until c. 7000 BC did Neolithic humans acquire reliable firemaking techniques, including friction from hardwood drills and sparks struck from flint against pyrites. Fire was used initially for warmth, light, and cooking; later it was used in fire drives in hunting and warfare, and for clearing forests of underbrush to facilitate hunting. The first agriculturalists used fire to clear fields and produce ash for fertilizer; such “slash-and-burn” cultivation is still used widely today. Fire also came to be used for firing pottery and for smelting bronze (c. 3000 BC) and later iron (c. 1000 BC). Much of the modern history of technology and science can be characterized as a continual increase in the amount of energy available through fire and brought under human control.
fire
fire [fīr]
Fire
Fire
The most ancient traces of the use of fire have been found in excavations of Sinanthropus and Neanderthal sites. Apparently man at first made use of fire generated by natural forces, such as lightning or spontaneous combustion of organic matter. Fire was first artificially generated at a much later time, most likely at the beginning of the Upper Paleolithic. Some ancient methods of making fire were scraping, drilling, and sawing, based on the friction of two pieces of wood against one another. Another method was striking sparks from flint. This method was improved at the beginning of the Iron Age with the help of steel and was used until the invention of phosphorus matches in the 19th century. The control of fire “for the first time gave man mastery over a certain force of nature and in this way once and for all separated man from the animal kingdom” (F. Engels, in K. Marx and F. Engels, Soch., 2nd ed. vol. 20, p. 117).
At first, fires were used for protection against the cold and predatory beasts, for illumination, and for the preparation of food. Fire evidently also played a significant role in the formation and consolidation of social ties within primitive hordes. First, maintenance of the fire demanded that members of the group perform coordinated duties. Second, all the vital activities of the primitive community were centered around the campfire or hearth. Man later learned to use fire for various technical purposes, such as mining flint, processing timber, and firing clay. Fire occupied an important place in the religious views and in the mythologies of many peoples.
REFERENCES
Anuchin, D. N. Otkrytie ognia isposoby ego dobyvaniia, 2nd ed. Moscow-Leningrad, 1926.Boriskovskii, P. I. “Osvoenie ognia.” In Kratkie soobshcheniia o dokladakh i polevykh issledovaniiakh In-ta istorii material’noi kul’lury, 1940, book 6.
Porshnev, B. F. “O drevneishem sposobe polucheniia ognia.” Sovetskaia etnografiia, 1955, no. 1.
V. M. BAKHTA
Fire
of all types of weapons, a means for destroying an enemy in battle on the ground, at sea, and in the air.
The strength of fire lies in its effectiveness and the ability to maneuver quickly and at the right moment. Fire is made effective by accuracy, concentration, surprise in application, and skillful control. Maneuvering of fire involves switching fire from certain targets to others in order to destroy them in sequence or simultaneously and concentrating the fire of various types of weapons against the key targets or sectors. Fire may be from artillery (including rocket, antiaircraft, and ship artillery), tanks, small arms, and other types of weapons.
Artillery employs fire on an individual target, convergent fire, the rolling barrage, successive concentrations, the standing barrage, the creeping barrage, and massed fire. Antiaircraft artillery uses convergent and barrage fire against the most important aerial targets. According to extent of damage to be inflicted, artillery employs annihilation fire (the target loses its combat capability completely), neutralization fire (the target is temporarily deprived of combat capability, maneuver is limited, and control is disrupted), and destruction fire against defense installations (the targets are made unsuitable for further use). Artillery wages fire by single rounds, platoon and battery fire, deliberate fire (with appointed time intervals between rounds), volley fire (rounds follow one another as quickly as possible), and salvo fire (all the guns of the battery or battalion fire simultaneously on command).
Among small arms, carbines (conventional rifles) wage fire by single rounds, submachine guns fire in short and long bursts or single rounds, and machine guns fire in short and long bursts or continuously. Fire by a squad, a platoon, and sometimes even a company that is opened up simultaneously on the command of the commander is called volley fire and is used against dense enemy combat formations to repulse an attack. Based on the direction of rifle and gun fire a distinction is made between frontal (directed at the front of the target), flank (at the flank of the target), and cross fire (at a single target from at least two directions). Fire by machine guns, individual field guns, and tanks that is opened up by surprise at very close range in one definite direction is called dagger fire in Russian.
G. M. SHINKAREV
Fire
uncontrolled burning that destroys property and endangers human life. All fires involve the chemical reaction of the burning substance with oxygen in the air, the release of great amounts of heat, and the rapid conversion of the combustion products into gases. Fires extinguished in their early stages and involving no losses constitute about 25 percent of the total number of fires. Only a small percentage of fires are major fires occurring in depots, warehouses, stores, and other places where goods are concentrated; the material damage resulting from these fires is considerable. In the USSR, for example, large fires account for 1 or 1.5 percent of all fires but 60 percent of all fire losses. In the USA, the National Fire Protection Association estimates yearly fire losses at about 3 billion dollars; the figure reaches 11 billion dollars if indirect losses are included. In 1972 in the USA, there were about 2.5 million fires, in which some 12,000 people died and some 300,000 were injured.
Fires are most frequently caused by carelessness, misuse of industrial equipment, spontaneous combustion of raw materials and finished products, static electricity, lightning, and arson. Based on where they originate, fires are classified as follows: fires on means of transport, steppe and field fires, underground fires in shafts and mines, peat and forest fires, and fires in buildings and structures. Fires in buildings and structures are in turn subdivided into open fires, in which flames and smoke are highly visible, and closed fires, in which the fire spreads along hidden pathways. The space involved by a fire is arbitrarily divided into three zones: the zone of active combustion, the zone of thermal effect; and the zone of smoke.
Externally, the zone of active combustion is marked by flame and glowing or smoldering materials. Oxygen in this zone is usually supplied from the air, although in some cases it results from the thermal decomposition of oxygen-containing combustible substances. Combustible structures and materials at the origin of the fire heat up and ignite as a result of the heat, and noncombustible materials lose their structural strength and warp.
The major factor contributing to the destructiveness of fires is the heat that develops as the fire burns. The temperature inside burning houses and public buildings ranges from 800° to 900°C. As Figure 1 shows, the heat in a burning room is not distributed uniformly. Figure 2 shows the difference in the temperatures of fires in enclosed spaces when various solid substances burn. As the amount of combustible material per unit floor area (fire load) increases, the maximum temperature and duration of the fire increases (Figure 3). As a rule, the highest temperatures are generated in open fires and average from 1200°C to 1350°C for combustible gases, from 1100° to 1300°C for liquids, and from 1000° to 1250°C for solids. When Thermit, Elektron (a magnesium-base alloy), or magnesium burn, the maximum temperatures range from 2000° to 3000°C. The heat released in the zone of combustion is transferred to the environment by convective and radiant heat exchange and as a result of thermal conductivity.
The zone of thermal effect is the area around the zone of combustion in which heat exchange produces heat that destroys surrounding objects and endangers human life. The zone of thermal effect is conventionally defined as the area surrounding the zone of combustion in which the heat generated by the mixture of air and gaseous combustion products is not less than 60° to
80°C and the surface density of the heat flux exceeds 4 kilowatts per m2, or 60 kilocalories per min-m3. During a fire, significant displacements of air and combustion products occur (Figure 4). The hot gaseous products rush upward, causing an influx of denser, cool air into the zone of combustion. In fires inside buildings, the rate of gas exchange depends on the dimensions and arrangement of openings in the walls and roof, the height of the rooms, and the amount and kind of combustible materials. The direction in which the heated products travel usually determines the way the fire will probably spread, since the intense rising heat currents may carry sparks, hot coals, and firebrands considerable distances and start new fires.
The combustion products released during a fire—smoke—create a smoke zone. The composition of smoke usually includes nitrogen, oxygen, carbon monoxide, carbon dioxide, water vapor, and ashes. Many of the products of complete and incomplete combustion found in smoke have high toxicity; this is especially true of products formed when polymers burn. In some cases, the products of incomplete combustion, such as carbon monoxide, may combine with oxygen to form combustible and explosive mixtures.
Fires may be extinguished by the action of cooling substances on the surface of the burning materials. Noncombustible vapors or gases may be used to dilute burning substances or air entering the zone of combustion, or a layer of insulation composed of fire-extinguishing substances may be created between the zone of combustion and the burning material or air. Water is the chief means of putting out fires. Streams of water are used to dispel smoke, provide protection from thermal radiation, and cool hot surfaces. In addition to water, fire-extinguishing agents include chemical and pressurized foams, carbon dioxide, nitrogen, powders, water vapor, and substances that stop the chemical reactions of combustion. Fire-extinguishing agents are applied at the base of the fire through the use of fire-fighting equipment; equipment includes fixed devices for fire extinguishing, fire engines, fire trains, fireboats, fire pumps, and fire extinguishers. Fire protection services and the supervisory personnel of individual facilities see to the measures needed to prevent and extinguish fires.
REFERENCES
Benson, S. Termokhimicheskaia kinetika. Moscow, 1971. (Translated from English).Monakhov, V. T. Metody issledovaniia pozharnoi opasnosti veshchestv. Moscow, 1972.
Demidov, P. G., V. A. Shandyba, and P. P. Shcheglov. Gorenie i svoistva goriuchikh veshchestv. Moscow, 1973.
P. S. SAVEL’EV
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