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Lightning

The lightning — so is called an electric discharge between two clouds, or between parts of the same cloud, or between a cloud and the earth. Distinguish three sorts of lightnings: linear, indistinct, or flat, and spherical.

1) The linear lightning has an appearance of the dazzling and bright twisting line with a set of branchings that it is possible to see well on pictures (for the first time in 1883; Ganzel and Shelter). The reason of tortuosity consists in various resistance to the category of various parts of the atmosphere, and it depends on various distribution of temperature, humidity, rain drops, dust and so forth. Sometimes the lightning forms knot or a loop (Eberkrombi, Engdemang, Reyman), sometimes shares on two, on three and more branches which meet then together (Nikolson, Kemtts, Lepel, of Leyst), sometimes consists of two parallel bright lines separated one from other narrow dark strip (Esse), sometimes happens a chetkoobrazna (Daguin, Joule).



Ordinary the lightning falls to the ground, but it happened to observe and such which rose from the earth in a cloud (Tippin, Simmons); such lightnings differ in special force. At the end of the 19th century считалост that a lightning, passing by air, scatters it in the parties of a particle and forms emptiness. Color of a linear lightning happens various, most often red, the white is more rare; apparently, it, by the way, depends on the distance, that is from thickness absorbing air layer beams. In a range of a lightning lines of nitrogen are clearly visible; claim that in it continuous color strips which attribute to the rarefied oxygen and small impurity of carbonic acid are besides noticeable (Kundt, Gershel, Vogel, Schuster).

Observers often point to the sulfuric smell heard after a lightning. It is the ozone which is formed of air oxygen under the influence of an electric discharge. Partly he is explained by decomposition of the organic and mineral substances which are on a surface of the earth and comprising sulfur and sulphurous connections. Duration of a lightning is small. Vitston on the basis of experiences with quickly rotating circle consisting of the alternating white and black sectors came to conclusion that it less than 1/1000 sec.; the newest supervision of the beginning of the 20th eyelid showed, however, that sometimes it much more.



It is very probable that the lightning submits itself not the simple, but oscillatory category (see. The oscillatory category, and also see the Lightning rod) with very large number of changes in a second. Recently thanks to the photo, except ordinary types of a linear lightning, three more began to be outlined: tape, tubular and vortex. In tape one physicists sees similarity to wide tapes of a polar light (see. Polar light); others believe that it represents herself double linear between which trunks there are intermediate categories; some, however, think that the image in the form of a tape comes from shift of the camera during an exposition or owing to influence of a windowpane through which ordinary remove. Tubular has an appearance of a light tube with several fiery streams from which the set of lateral branches separates (Kayser, Pilchikov). Vortex represents itself a fiery whirlwind (Pilchikov, Tsenter, Muzet). Perhaps, any ordinary linear lightning belongs to one of these three types, but it seems to an eye and everything more often it turns out in the photo in the form of the line owing to remoteness of distance.

Length of a lightning can approximately be determined, knowing the distances from initial and final points of a lightning to the observer found on periods between emergence of a lightning and the beginning and the end of a thunder (see the Thunder), and to the point of view corresponding to these points (two parties of a triangle and a corner between them are known, we will find a third). D'Abbadi determined in such way the lightning length 19 km. The franc some found length 49 km. It isn't difficult to explain formation of such long lightning. On the look standard now for the first time stated by Ehrman and Peltye, the main phenomena of electrization in the atmosphere an essence result of induction of the earth loaded negatively. Owing to induction the earth and a storm cloud have some potential difference, and the lower part of a cloud is loaded with electricity of an opposite sign compared with the earth. At increase in density of a cloud (see. The thunder-storm) occurs merge of its water particles and, therefore, reduction of their surface that conducts for itself increase in a potential difference between the earth and a cloud in some tens and hundreds of thousands of times. This difference is quite sufficient to make a number of categories between the rain drops located between a cloud and the earth as is called as a lightning.



2) Lightnings of the 2nd sort, indistinct, have an appearance of instant flash, without certain contours, and submit the category between the parts of the same cloud possessing a considerable potential difference; the vagueness is explained by semi-conductivity of a cloud. Color of this sort of lightnings most part red, sometimes blue or violet. Across Arago, hundreds and thousands of indistinct fall on one linear lightning. Some summer lightnings which, in general, are meant as lightnings without thunder also concern to the last.

3) The third sort of lightnings — spherical — the most dangerous. During a strong thunder-storm between a cloud and the earth there is sometimes a fiery sphere, everything is more often than reddish-yellow color, surrounded with the light atmosphere without certain contours which moves ordinary very incorrectly, sometimes quickly, but the most part so slowly that it is possible to keep up with it a fluent step. Having approached the building, it goes along a roof; having met the lightning rod, quite often passes into nothingness with a strong crash. The fireball can get in the house even through a narrow opening, being narrowed thus, and at an exit from an opening accepts the initial sizes. Sometimes it vanishes without noise, but blows up with a strong crash more often. Flying by near the person, it will contuse, and quite often and kills him.

Fireballs are more often than everything happen in the tropical countries where they are constant satellites of hurricanes (see Storms). Плантэ made a number of the phenomena representing big analogy to a fireball and a little explaining this puzzle. It connects a negative pole of very strong battery of accumulators in some thousands of volts to slightly oxidized water poured in a vessel, and the end of the wire going to a positive pole approaches to a water surface; between them there is a shining ball which at a raising of the end of a wire increases to 1 стм. in the diameter, at movement of a wire moves itself on a water surface aside, rotating; then blows up with a crash. The spectral analysis indicates presence in it of oxygen and components of water vapor. The similar fiery sphere rotating quickly and incorrectly moving of Plante received between two damp horizontal cardboards connected to poles of very strong battery. According to Plante, the similar phenomenon, but in big sizes, has to occur and between strongly electrified by opposite elektrichestvo the earth and a thundercloud if the last close approaches the first. Other condition which for this purpose has to be apparently observed, is lack of the rain turning the category in linear.



In 1895 A.S. Popov arranged the device (electrocount) who notes each lightning; it is based on the discovery made by Branli in 1891 and confirmed with researches of Ladzha and Popov that conductivity металлич. powder increases in many hundreds of times under the influence of the events near the oscillatory category. The device consists of the ordinary lightning rod near which horizontally glass tube to a half filled with sawdust from soft iron is placed. The last are entered into one chain with the small galvanic battery and a call. The battery undertakes such force that under ordinary conditions the call didn't work. The lightning, at least even remote, induces the category in the lightning rod, conductivity of sawdust increases, and the call calls. The hammer of the last is established so that it at the return movement strikes about a tube with sawdust and brings them into an initial state, why current now stops.

Still the electromagnet to which anchor the special feather is attached is attached to the device; at each category it does a hyphen on paper: to a tape, slowly moving by means of a clockwork. The device, first, confirms that look that the lightning is the oscillatory category, secondly — often finds electric discharges when them and didn't assume, e.g. in a cumulus cloud, before the heavy rain which isn't followed by a thunder-storm and so forth. It can give useful instructions for a thunder-storm prediction (phone also indicates the remote thunder-storm: in it the characteristic crash is audible).

The lightning stroke is always sent to that body which represents less than resistance — to metal subjects, to the damp soil etc.; the blow to the dry soil indicates proximity to a surface of its soil water. The clay and sandy soil is subject to more frequent blows; more rare — limy. At blow to the sandy soil the last melts and then hardens in the form of long (sometimes to 10 m at 5 cm шир.), the vitreous tubes pointed from top to bottom called by fulgurita.



Passing through bodies, the lightning heats them the more, than more their resistance. Thin a wire melt and disappear, easily flammable bodies light up, liquids evaporate; dry trees of M. are lit, fresh are split at what it rips off them skin. Steam which is formed of juice probably takes part in it. Blows are more often than everything happen are sent to an oak, than everything is more rare — in a beech that, apparently, depends on various amount of fat oils in them representing the big resistance to electricity (Zhonesko's experiences). In the content of fat oils in the winter and in the summer probably that in winter blows in trees happen less than in the summer, under identical other conditions (Gelman) depends on distinction.

Sometimes the lightning strikes people and animals owing to so-called returnable blow: in a body under the influence of the electrified cloud the electricity of an opposite sign is induced, and the electricity of the same sign goes to the earth; when the cloud is discharged by action of other cloud or blow to the earth somewhere aside, the electricity which collected in a body instantly goes to the earth that makes mechanical and chemical action which often conducts for itself death without any external trace.

Magnets under the influence of a lightning change the magnetic properties, are quite often remagnetized; pieces of iron and steel, opposite to that, are magnetized; chronometers often change the course.

Sometimes actions of lightnings are very strange, e.g. alloyage of coins in a bag which remains intact, or transfer of metal vapors from one subject on another where they give a print of the first, etc. Many similar facts are given in Arago's composition "Thunder and a lightning" (Hotinsky's translation, 1859), and also in "Works of a network of the southwest of Russia" of the prof. A.V. Klossovsky. Recently these facts began to find to themselves an explanation thanks to opening of special characteristics of oscillatory categories.

Repeatability of blows of lightnings in Europe in the last tens years increases (Goltts, Betsold, Lang, Kasner and the friend., 1900). The reason consists, apparently, in deforestation, in increase in networks of the railroads and telegraphs, in carrying out sewer pipes, in increase in number of factories and so forth, and also in increase in amount of dust in air. For the same reasons it in the cities is more, than in not occupied places.

Literature, except the specified:

Плантэ, "The electric phenomena in the atmosphere" (Anisimov's translation, 1891). Many articles about M. are placed in magazines: "Zeitschr. der Oesterr. Ges. f u r Meteorologie", "Meteorol. Zeitschr. der Deutsch. Meteor. Gesellschaft", "Ciel et Terre", "Symon's Meteorological Magazin", "Meteorol. messenger Imper. русск. геогр. general", "Comptes Rendus des s eances de l'Acade mie des Sciences". In the May book "Meteorol. the messenger" (1896) the instruction for photography of lightnings of the prof. N. D. Pilchikov to which three interesting pictures of lightnings are attached is printed.

Lightning stroke (medical). The lightning can kill the person, without leaving on his body any signs of damage. Sometimes find the burned wounds singed a hair and superficial burns on skin. At struck by a lightning sometimes the phenomena, by nothing different from ordinary concussion are noticed. Within several minutes or even the whole hour and more, the victim is in unconsciousness; he slowly breathes, pulse is swept hardly up, pupils are expanded, and cyanosis often joins all this. After a while sometimes there are continuous frustration, e.g. paralyzes of extremities, mainly lower, or frustration of separate feelings: a blindness, metal taste in a mouth, noise in ears. In certain cases after a lightning stroke the nonsense, mania and loss of memory were observed.



Passing of a lightning through a body is followed by many objective phenomena. First of all, it the phenomena of mechanical property, more, less expressed. So, places of occurrence and a vykhozhdeniye of a lightning can be designated on a body by wounds, as if from the stupid or pricking tool. Fractures of bones and a rupture of an eardrum were observed even. Then, on a body eritematozny and krapivny spots, superficial bruises and burns are noticed. On skin treelike branchings, so-called patterns of a lightning are often visible. The origin of these red strips at the beginning of the 20th century wasn't found out yet.

The estuary observed at the killed a lightning the real rupture of internal body, without external damage. On a heart top in a partition the opening with unequal walls, 2 стм was formed. in the diameter, connecting both ventricles. The opening was executed by a black blood parcel. The injuries of eyes made by a lightning stroke are most carefully studied. The reason of the cataract caused by a lightning is explained, however, by unequally various scientists (Leber, Fossius, Knis).

After a lightning stroke also the temporary blindness which can proceed some months was observed. In other cases the blindness and remained incurable and was caused by an inflammation of an optic nerve or outpourings of blood in the field of a yellow spot and a nipple. Among other frustration — mostly quickly passing — the century, expansion or narrowing of pupils and paralyzes of accommodation were observed omission.



Treatment of the victims for lightnings has to seek for revival and maintenance of breath and blood circulation. Cold souls are capable to bring big benefit; it is also possible to recommend grinding of members, warming of extremities and application of stimulants through a mouth or in the form of klistir. Private damages to be subject to corresponding treatment. Cases of death and defeats from a lightning are frequent. The statistics of Prussia for 1854 — 1857 shows 511 people struck with lightnings, from them 72,25% were killed and 27,75% incurred heavy damages. In France for 1835 — 1865 came 2431 cases of death from a lightning stroke, so — on average 72,7 annually.

When writing this text material was used from
Encyclopedic dictionary of Brockhaus F.A. and Efron I.A. (1890 — 1907).


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