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Monday, November 11, 2024

Frankenstein

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Frankenstein
Frankenstein; or, The Modern Prometheus
Volume I, first edition
AuthorMary Shelley
LanguageEnglish
GenreGothic novel, horror fiction, science fiction
Set inEngland, Ireland, Italy, France, Scotland, Old Swiss Confederacy, Russian Empire, Holy Roman Empire; late 18th century
Published1 January 1818; 206 years ago
PublisherLackington, Hughes, Harding, Mavor & Jones
Publication placeEngland
Pages280
823.7
LC ClassPR5397 .F7
Preceded byHistory of a Six Weeks' Tour 
Followed byValperga 
TextFrankenstein; or, The Modern Prometheus at Wikisource

Frankenstein; or, The Modern Prometheus is an 1818 Gothic novel written by English author Mary Shelley. Frankenstein tells the story of Victor Frankenstein, a young scientist who creates a sapient creature in an unorthodox scientific experiment. Shelley started writing the story when she was 18, and the first edition was published anonymously in London on 1 January 1818, when she was 20. Her name first appeared in the second edition, which was published in Paris in 1821.

Shelley travelled through Europe in 1815, moving along the river Rhine in Germany, and stopping in Gernsheim, 17 kilometres (11 mi) away from Frankenstein Castle, where, about a century earlier, Johann Konrad Dippel, an alchemist, had engaged in experiments. She then journeyed to the region of Geneva, Switzerland, where much of the story takes place. Galvanism and occult ideas were topics of conversation for her companions, particularly for her lover and future husband Percy Bysshe Shelley.

In 1816, Mary, Percy, John Polidori, and Lord Byron had a competition to see who wrote the best horror story. After thinking for days, Shelley was inspired to write Frankenstein after imagining a scientist who created life and was horrified by what he had made.

Frankenstein is one of the most well-known works of English literature. Infused with elements of the Gothic novel and the Romantic movement, it has had a considerable influence on literature and on popular culture, spawning a complete genre of horror stories, films, and plays. Since the publication of the novel, the name "Frankenstein" has often been used, erroneously, to refer to the monster, rather than to his creator/father.

Summary

Captain Walton introductory narrative

Frankenstein is a frame story written in epistolary form. Set in the 18th century, it documents a fictional correspondence between Captain Robert Walton and his sister, Margaret Walton Saville. Robert Walton is a failed writer who sets out to explore the North Pole in hopes of expanding scientific knowledge. After departing from Archangel, the ship is trapped by pack ice on the journey across the Arctic Ocean. During this time, the crew spots a dog sled driven by a gigantic figure. A few hours later, the ice splits apart, freeing the ship, and the crew rescues a nearly frozen and emaciated man named Victor Frankenstein from a drifting ice floe. Frankenstein has been in pursuit of the gigantic man observed by Walton's crew. Frankenstein starts to recover from his exertion; he sees in Walton the same obsession that has destroyed him and recounts a story of his life's miseries to Walton as a warning. The recounted story serves as the frame for Frankenstein's narrative.

Victor Frankenstein's narrative

Victor begins by telling of his childhood. Born in Naples, Italy, into a wealthy Genevan family, Victor and his younger brothers, Ernest and William, are sons of Alphonse Frankenstein and the former Caroline Beaufort. From a young age, Victor has a strong desire to understand the world. He is obsessed with studying theories of alchemists, though when he is older he realizes that such theories are considerably outdated. When Victor is five years old, his parents adopt Elizabeth Lavenza (the orphaned daughter of an expropriated Italian nobleman) whom Victor plans to marry. Victor's parents later take in another child, Justine Moritz, who becomes William's nanny.

Weeks before he leaves for the University of Ingolstadt in Germany, his mother dies of scarlet fever; Victor buries himself in his experiments to deal with the grief. At the university, he excels at chemistry and other sciences, soon developing a secret technique to impart life to non-living matter. He undertakes the creation of a humanoid, but due to the difficulty in replicating the minute parts of the human body, Victor makes the Creature tall, about 8 feet (2.4 m) in height, and proportionally large. Victor works at gathering the vital organs by pilfering charnel houses, mortuaries and by entrapping and vivisecting feral animals. Despite Victor selecting its features to be beautiful, upon animation the Creature is instead hideous, with dull and watery yellow eyes and yellow skin that barely conceals the muscles and blood vessels underneath. Repulsed by his work, Victor flees. While wandering the streets the next day, he meets his childhood friend, Henry Clerval, and takes Clerval back to his apartment, fearful of Clerval's reaction if he sees the monster. However, when Victor returns to his laboratory, the Creature is gone.

Victor falls ill from the experience and is nursed back to health by Clerval. After recovering he forgets about the Creature and goes into Clerval's study of Oriental languages, which he considers the happiest time of his academic career. This is cut short when Victor receives a letter from his father notifying him of the murder of his brother William. Near Geneva, Victor sees a large figure and becomes convinced that his creation is responsible. Justine Moritz, William's nanny, is convicted of the crime after William's locket, which contained a miniature portrait of Caroline, is found in her pocket. Victor knows that no one will believe him if he testifies that it was the doing of the Creature; Justine is hanged. Ravaged by grief and guilt, Victor takes up mountain climbing in the Alps. While hiking through Mont Blanc's Mer de Glace, he is suddenly approached by the Creature, who insists that Victor hear his tale.

The Creature's narrative

Intelligent and articulate, the Creature relates his first days of life, living alone in the wilderness. He found that people were afraid of him and hated him due to his appearance, which led him to fear and hide from them. While living in an abandoned structure connected to a cottage, he grew fond of the poor family living there and discreetly collected firewood for them, cleared snow away from their path, and performed other tasks to help them. Secretly living next to the cottage for months, the Creature learned that the son was going to marry a Turkish woman whom he was teaching his native language, which the Creature listened in on the lessons and taught himself to speak and write. The Creature also taught himself to read after discovering a lost satchel of books in the woods. When he saw his reflection in a pool, he realized his appearance was hideous, and it horrified him as much as it horrified normal humans. As he continued to learn of the family's plight, he grew increasingly attached to them, and eventually he approached the family in hopes of becoming their friend, entering the house while only the blind father was present. The two conversed, but on the return of the others, the rest of them were frightened. The blind man's son attacked him and the Creature fled the house. The next day, the family left their home out of fear that he would return. Witnessing this, the monster renounced any hope of being accepted by humanity, and vowed to get his revenge. Although he hated his creator for abandoning him, he decided to travel to Geneva to find him because he believed that Victor was the only person with a responsibility to help him. On the journey, he rescued a child who had fallen into a river, but her father, believing that the Creature intended to harm them, shot him in the shoulder. The Creature then swore revenge against all humans. He travelled to Geneva using details from a combination of Victor's journal and geography lessons gleaned from the family. When in Switzerland he chanced upon William, who was at first frightened, and the Creature held his wrist to calm him. When the boy screamed his full name and that he had powerful parents, this sparked the creature into killing the boy to spite Victor. The Creature then took William's locket and placed it into the dress of Justine, incriminating her as the murderer.

The Creature demands that Victor create a female companion like himself. He argues that as a living being, he has a right to happiness. The Creature promises that he and his mate will vanish into the South American wilderness, never to reappear, if Victor grants his request. Should Victor refuse, the Creature threatens to kill Victor's remaining friends and loved ones and not stop until he completely ruins him. Fearing for his family, Victor reluctantly agrees. The Creature says he will watch over Victor's progress.

Victor Frankenstein's narrative resumes

Clerval accompanies Victor to England, but they separate, at Victor's insistence, at Perth, in Scotland. Travelling to Orkney to build the second creature, Victor suspects that the Creature is following him. As he works on the new creature, he is plagued by premonitions of disaster. He fears that the female will hate the Creature - or worse still - be even more evil than he is. Even more worrying to him is the idea that creating the second creature might lead to the creation of a race of beings just as strong as the monster who could plague humanity. He tears apart the unfinished female creature after he sees the Creature, who had indeed followed Victor, watching through a window. The Creature immediately bursts through the door to confront Victor and demands he repair his destruction and resume work, but Victor refuses. The Creature leaves, but gives a final threat: "I will be with you on your wedding night." Victor interprets this as a threat upon his life, believing that the Creature will kill him after he finally becomes happy.

Victor sails out to sea to dispose of his instruments, and falls asleep in the boat. He awakens some time later, and is unable to return to shore due to a change in the wind, and falls unconscious, drifting to Ireland. When Victor awakens, he is arrested for murder. Despite the severity of the charges, he is met with sympathy from the magistrate in charge of the trial, which suggests that the case is crumbling. Victor is acquitted when eyewitness testimony confirms that he was in Orkney at the time the murder took place. However, when shown the murder victim, Victor is horrified to see it was Henry Clerval, whom the Creature strangled as part of his promise to kill all his friends and family. Victor suffers another mental breakdown and after recovering, he returns home with his father, who has restored to Elizabeth some of her father's fortune. His father does not know of the cause behind the murders of William and Henry, but senses a curse and begs Victor to honour his mother's last wish that Victor marry Elizabeth.

In Geneva, Victor is about to marry Elizabeth and prepares to fight the Creature to the death, arming himself with pistols and a dagger. The night following their wedding, Victor asks Elizabeth to stay in her room while he looks for "the fiend". While Victor searches the house and grounds, the Creature strangles Elizabeth. From the window, Victor sees the Creature, who tauntingly points at Elizabeth's corpse; Victor tries to shoot him, but the Creature escapes. Victor's father, weakened by age and by the death of Elizabeth, dies a few days later. Seeking revenge, Victor pursues the Creature across Europe and Russia, though his adversary stays one step ahead of him at all times. Eventually, the chase leads to the Arctic Ocean and then on towards the North Pole, and Victor reaches a point where he is within a mile of the Creature, but he collapses from exhaustion and hypothermia before he can find his quarry, allowing the Creature to escape. Eventually the ice around Victor's sledge breaks apart, and the resultant ice floe comes within range of Walton's ship.

Captain Walton's conclusion

At the end of Victor's narrative, Captain Walton resumes telling the story. A few days after the Creature vanishes, the ship is trapped by pack ice for a second time, and several crewmen die in the cold before the rest of Walton's crew insists on returning south once it is freed. Upon hearing the crew's demands, Victor is angered and, despite his condition, gives a powerful speech to them. He reminds them of why they chose to join the expedition and that it is hardship and danger, not comfort, that defines a glorious undertaking such as theirs. He urges them to be men, not cowards. However, although the speech makes an impression on the crew, it is not enough to change their minds. Knowing that continuing on would surely result in mutiny, Walton agrees to abandon the voyage and return home, but Victor, despite his condition, declares that he will continue to hunt the Creature, and is adamant that he must be killed.

Victor dies shortly thereafter, telling Walton, in his last words, to seek "happiness in tranquillity and avoid ambition" but then refuting this, speculating that some other scientist might succeed where he has failed. Walton discovers the Creature on his ship, mourning over Victor's body. The Creature tells Walton that Victor's death has not brought him peace; rather, his crimes have made him even more miserable than Victor ever was. The Creature vows to burn himself on a funeral pyre so that no one else will ever know of his existence. Walton watches as the Creature drifts away on an ice raft, never to be seen again.

Author's background

Mary Shelley by Richard Rothwell (1840–41)

Mary Shelley's mother, Mary Wollstonecraft, died from infection eleven days after giving birth to her. Shelley grew close to her father, William Godwin, having never known her mother. Godwin hired a nurse, who briefly cared for her and her half sister, before marrying his second wife Mary Jane Clairmont, who did not like the close bond between Shelley and her father. The resulting friction caused Godwin to favour his other children.

Shelley's father was a famous author of the time, and her education was of great importance to him, although it was not formal. Shelley grew up surrounded by her father's friends, writers, and persons of political importance, who often gathered at the family home. This inspired her authorship at an early age. Mary, at the age of sixteen, met Percy Bysshe Shelley (who later became her husband) while he was visiting her father. Godwin did not approve of the relationship between his daughter and an older, married man, so they fled to France along with her stepsister, Claire Clairmont. On 22 February 1815, Shelley gave birth prematurely to her first child, Clara, who died two weeks later.

In the summer of 1816, Mary, Percy, and Claire took a trip to visit Claire's lover, Lord Byron, in Geneva. Poor weather conditions, more akin to winter, forced Byron and the visitors to stay indoors. To help pass time, Byron suggested that he, Mary, Percy, and Byron's physician, John Polidori, have a competition to write the best ghost story to pass time stuck indoors. Mary was just eighteen years old when she won the contest with her creation of Frankenstein.

Literary influences

Shelley's work was heavily influenced by that of her parents. Her father was famous for Enquiry Concerning Political Justice and her mother famous for A Vindication of the Rights of Woman. Her father's novels also influenced her writing of Frankenstein. These novels included Things as They Are; or, The Adventures of Caleb Williams, St. Leon, and Fleetwood. All of these books were set in Switzerland, similar to the setting in Frankenstein. Some major themes of social affections and the renewal of life that appear in Shelley's novel stem from these works she had in her possession. Other literary influences that appear in Frankenstein are Pygmalion et Galatée by Mme de Genlis, and Ovid, with the use of individuals identifying the problems with society. Ovid also inspires the use of Prometheus in Shelley's title.

The influence of John Milton's Paradise Lost and Samuel Taylor Coleridge's The Rime of the Ancient Mariner are evident in the novel. In The Frankenstein of the French Revolution, author Julia Douthwaite posits that Shelley probably acquired some ideas for Frankenstein's character from Humphry Davy's book Elements of Chemical Philosophy, in which he had written that "science has ... bestowed upon man powers which may be called creative; which have enabled him to change and modify the beings around him ...". References to the French Revolution run through the novel; a likely source is François-Félix Nogaret [fr]'s Le Miroir des événemens actuels, ou la Belle au plus offrant (1790), a political parable about scientific progress featuring an inventor named Frankésteïn, who creates a life-sized automaton.

Both Frankenstein and the monster quote passages from Percy Shelley's 1816 poem, "Mutability", and its theme of the role of the subconscious is discussed in prose. Percy Shelley's name never appeared as the author of the poem, although the novel credits other quoted poets by name. Samuel Taylor Coleridge's poem "The Rime of the Ancient Mariner" (1798) is associated with the theme of guilt and William Wordsworth's "Tintern Abbey" (1798) with that of innocence.

Many writers and historians have attempted to associate several then-popular natural philosophers (now called physical scientists) with Shelley's work because of several notable similarities. Two of the most noted natural philosophers among Shelley's contemporaries were Giovanni Aldini, who made many public attempts at human reanimation through bio-electric Galvanism in London, and Johann Konrad Dippel, who was supposed to have developed chemical means to extend the life span of humans. While Shelley was aware of both of these men and their activities, she makes no mention of or reference to them or their experiments in any of her published or released notes.

Ideas about life and death discussed by Percy and Byron were of great interest to scientists of that time. They discussed ideas from Erasmus Darwin and the experiments of Luigi Galvani as well as James Lind. Mary joined these conversations and the ideas of Darwin, Galvani and perhaps Lind were present in her novel.

Shelley's personal experiences also influenced the themes within Frankenstein. The themes of loss, guilt, and the consequences of defying nature present in the novel all developed from Mary Shelley's own life. The loss of her mother, the relationship with her father, and the death of her first child are thought to have inspired the monster and his separation from parental guidance. In a 1965 issue of The Journal of Religion and Health a psychologist proposed that the theme of guilt stemmed from her not feeling good enough for Percy because of the loss of their child.

Composition

Draft of Frankenstein ("It was on a dreary night of November that I beheld my man completed ...")

During the rainy summer of 1816, the "Year Without a Summer", the world was locked in a long, cold volcanic winter caused by the eruption of Mount Tambora in 1815. Mary Shelley, aged 18, and her lover (and future husband), Percy Bysshe Shelley, visited Lord Byron at the Villa Diodati by Lake Geneva, in Switzerland's Alps. The weather was too cold and dreary that summer to enjoy the outdoor holiday activities they had planned, so the group retired indoors until dawn.

Sitting around a log fire at Byron's villa, the company amused themselves by reading German ghost stories translated into French from the book Fantasmagoriana. Byron proposed that they "each write a ghost story." Unable to think of a story, Mary Shelley became anxious. She recalled being asked "Have you thought of a story?" each morning, and every time being "forced to reply with a mortifying negative." During one evening in the middle of summer, the discussions turned to the nature of the principle of life. "Perhaps a corpse would be re-animated," Mary noted, "galvanism had given token of such things". It was after midnight before they retired and, unable to sleep, she became possessed by her imagination as she beheld the "grim terrors" of her "waking dream".

I saw the pale student of unhallowed arts kneeling beside the thing he had put together. I saw the hideous phantasm of a man stretched out, and then, on the working of some powerful engine, show signs of life, and stir with an uneasy, half vital motion. Frightful must it be; for supremely frightful would be the effect of any human endeavour to mock the stupendous mechanism of the Creator of the world.

In September 2011, astronomer Donald Olson, after a visit to the Lake Geneva villa the previous year and inspecting data about the motion of the moon and stars, concluded that her "waking dream" took place between 2 a.m. and 3 a.m. on 16 June 1816, several days after the initial idea by Lord Byron that they each write a ghost story.

Mary Shelley began writing what she assumed would be a short story, but with Percy Shelley's encouragement, she expanded the tale into a fully-fledged novel. She later described that summer in Switzerland as the moment "when I first stepped out from childhood into life." Shelley wrote the first four chapters in the weeks following the suicide of her half-sister Fanny. This was one of many personal tragedies that impacted Shelley's work. Shelley's first child died in infancy, and when she began composing Frankenstein in 1816, she was probably nursing her second child, who was also dead by the time of Frankenstein's publication. Shelley wrote much of the book while residing in a lodging house in the centre of Bath in 1816.

Byron managed to write just a fragment based on the vampire legends he heard while travelling the Balkans, and from this John Polidori created The Vampyre (1819), the progenitor of the romantic vampire literary genre. Thus two seminal horror tales originated from the conclave.

The group talked about Enlightenment and Counter-Enlightenment ideas as well. Mary Shelley believed the Enlightenment idea that society could progress and grow if political leaders used their powers responsibly; however, she also believed the Romantic ideal that misused power could destroy society.

Shelley's manuscripts for the first three-volume edition in 1818 (written 1816–1817), as well as the fair copy for her publisher, are now housed in the Bodleian Library in Oxford. The Bodleian acquired the papers in 2004, and they belong now to the Abinger Collection. In 2008, the Bodleian published a new edition of Frankenstein, edited by Charles E. Robinson, that contains comparisons of Mary Shelley's original text with Percy Shelley's additions and interventions alongside.

Frankenstein and the Monster

The Creature

An English editorial cartoonist conceives the Irish Fenian movement as akin to Frankenstein's creature, in the wake of the Phoenix Park murders in an 1882 issue of Punch.

Although the Creature was described in later works as a composite of whole body parts grafted together from cadavers and reanimated by the use of electricity, this description is not consistent with Shelley's work; both the use of electricity and the cobbled-together image of Frankenstein's monster were more the result of James Whale's popular 1931 film adaptation of the story and other early motion-picture works based on the creature. In Shelley's original work, Victor Frankenstein discovers a previously unknown but elemental principle of life, and that insight allows him to develop a method to imbue vitality into inanimate matter, though the exact nature of the process is left ambiguous. After a great deal of hesitation in exercising this power, Frankenstein spends two years painstakingly constructing the Creature's body (one anatomical feature at a time, from raw materials supplied by "the dissecting room and the slaughter-house"), which he then brings to life using his unspecified process.

Newspaper illustrations from abridged versions of Frankenstein, 1910

Part of Frankenstein's rejection of his creation is the fact that he does not give him a name. Instead, Frankenstein's creation is referred to by words such as "wretch", "monster", "creature", "demon", "devil", "fiend", and "it". When Frankenstein converses with the creature, he addresses him as "vile insect", "abhorred monster", "fiend", "wretched devil", and "abhorred devil".

In the novel, the creature is compared to Adam, the first man in the Garden of Eden. The monster also compares himself with the "fallen" angel. Speaking to Frankenstein, the monster says "I ought to be thy Adam, but I am rather the fallen angel". That angel would be Lucifer (meaning "light-bringer") in Milton's Paradise Lost, which the monster has read. Adam is also referred to in the epigraph of the 1818 edition:

Did I request thee, Maker, from my clay
To mould Me man? Did I solicit thee
From darkness to promote me?

Some have posited the creature as a composite of Percy Shelley and Thomas Paine. If the creature's hatred for Victor and his desire to raise a child mirror Percy's filial rebelliousness and his longing to adopt children, his desire to do good and his persecution can be said to echo Paine's utopian visions and fate in England.

The Creature has often been mistakenly called Frankenstein. In 1908, one author said "It is strange to note how well-nigh universally the term "Frankenstein" is misused, even by intelligent people, as describing some hideous monster." Edith Wharton's The Reef (1916) describes an unruly child as an "infant Frankenstein". David Lindsay's "The Bridal Ornament", published in The Rover, 12 June 1844, mentioned "the maker of poor Frankenstein". After the release of Whale's cinematic Frankenstein, the public at large began speaking of the Creature itself as "Frankenstein". This misnomer continued with the successful sequel Bride of Frankenstein (1935), as well as in film titles such as Abbott and Costello Meet Frankenstein.

Illustration by Theodor von Holst from the frontispiece of the 1831 edition

Origin of Victor Frankenstein's name

Mary Shelley maintained that she derived the name Frankenstein from a dream-vision. This claim has since been disputed and debated by scholars that have suggested alternative sources for Shelley's inspiration. The German name Frankenstein means "stone of the Franks", and is associated with various places in Germany, including Frankenstein Castle (Burg Frankenstein) in Darmstadt, Hesse, and Frankenstein Castle in Frankenstein, a town in the Palatinate. There is also a castle called Frankenstein in Bad Salzungen, Thuringia, and a municipality called Frankenstein in Saxony. The town of Frankenstein in Silesia (now Ząbkowice, Poland) was the site of a scandal involving gravediggers in 1606, and this has been suggested as an inspiration to the author. Finally, the name is borne by the aristocratic House of Franckenstein from Franconia.

Radu Florescu argued that Mary and Percy Shelley visited Frankenstein Castle near Darmstadt in 1814, where alchemist Johann Konrad Dippel had experimented with human bodies, and reasoned that Mary suppressed mention of her visit to maintain her public claim of originality. A literary essay by A.J. Day supports Florescu's position that Mary Shelley knew of and visited Frankenstein Castle before writing her debut novel. Day includes details of an alleged description of the Frankenstein castle in Mary Shelley's "lost journals". However, according to Jörg Heléne, Day's and Florescu's claims cannot be verified.

A possible interpretation of the name "Victor" is derived from Paradise Lost by John Milton, a great influence on Shelley (a quotation from Paradise Lost is on the opening page of Frankenstein and Shelley writes that the monster reads it in the novel). Milton frequently refers to God as "the victor" in Paradise Lost, and Victor's creation of life in the novel is compared to God's creation of life in Paradise Lost. In addition, Shelley's portrayal of the monster owes much to the character of Satan in Paradise Lost; and, the monster says in the story, after reading the epic poem, that he empathizes with Satan's role.

Parallels between Victor Frankenstein and Mary's husband, Percy Shelley, have also been drawn. Percy Shelley was the first-born son of a wealthy country squire with strong political connections and a descendant of Sir Bysshe Shelley, 1st Baronet of Castle Goring, and Richard Fitzalan, 10th Earl of Arundel. Similarly, Victor's family is one of the most distinguished of that republic and his ancestors were counsellors and syndics. Percy's sister and Victor's adopted sister were both named Elizabeth. There are many other similarities, from Percy's usage of "Victor" as a pen name for Original Poetry by Victor and Cazire, a collection of poetry he wrote with Elizabeth, to Percy's days at Eton, where he had "experimented with electricity and magnetism as well as with gunpowder and numerous chemical reactions," and the way in which Percy's rooms at Oxford were filled with scientific equipment.

Modern Prometheus

The Modern Prometheus is the novel's subtitle (though modern editions now drop it, only mentioning it in introduction). Prometheus, in versions of Greek mythology, was the Titan who created humans in the image of the gods so that they could have a spirit breathed into them at the behest of Zeus. Prometheus then taught humans to hunt, but after he tricked Zeus into accepting "poor-quality offerings" from humans, Zeus kept fire from humankind. Prometheus took back the fire from Zeus to give to humanity. When Zeus discovered this, he sentenced Prometheus to be eternally punished by fixing him to a rock of Caucasus, where each day an eagle pecked out his liver, only for the liver to regrow the next day because of his immortality as a god.

As a Pythagorean, or believer in An Essay on Abstinence from Animal Food, as a Moral Duty by Joseph Ritson, Mary Shelley saw Prometheus not as a hero but rather as something of a devil, and blamed him for bringing fire to humanity and thereby seducing the human race to the vice of eating meat. Percy wrote several essays on what became known as vegetarianism including A Vindication of Natural Diet.

In 1910, Edison Studios released the first motion-picture adaptation of Shelley's story.

Byron was particularly attached to the play Prometheus Bound by Aeschylus, and Percy Shelley soon wrote his own Prometheus Unbound (1820). The term "Modern Prometheus" was derived from Immanuel Kant who described Benjamin Franklin as the "Prometheus of modern times" in reference to his experiments with electricity.

Publication

Shelley completed her writing in April/May 1817, and Frankenstein; or, The Modern Prometheus was published on 1 January 1818 by the small London publishing house Lackington, Hughes, Harding, Mavor, & Jones. It was issued anonymously, with a preface written for Mary by Percy Bysshe Shelley and with a dedication to philosopher William Godwin, her father. It was published in an edition of just 500 copies in three volumes, the standard "triple-decker" format for 19th-century first editions.

A variety of different editions

A French translation (Frankenstein: ou le Prométhée Moderne, translated by Jules Saladin) appeared as early as 1821. The second English edition of Frankenstein was published on 11 August 1823 in two volumes (by G. and W. B. Whittaker) following the success of the stage play Presumption; or, the Fate of Frankenstein by Richard Brinsley Peake. This edition credited Mary Shelley as the book's author on its title page.

On 31 October 1831, the first "popular" edition in one volume appeared, published by Henry Colburn & Richard Bentley. This edition was heavily revised by Mary Shelley, partially to make the story less radical. It included a lengthy new preface by the author, presenting a somewhat embellished version of the genesis of the story. This edition is the one most widely published and read now, although a few editions follow the 1818 text. Some scholars such as Anne K. Mellor prefer the original version, arguing that it preserves the spirit of Mary Shelley's vision.

Reception

Frankenstein has been both well received and disregarded since its anonymous publication in 1818. Critical reviews of that time demonstrate these two views, along with confused speculation as to the identity of the author. Walter Scott, writing in Blackwood's Edinburgh Magazine, praises the novel as an "extraordinary tale, in which the author seems to us to disclose uncommon powers of poetic imagination," although he was less convinced about the way in which the monster gains knowledge about the world and language. La Belle Assemblée described the novel as "very bold fiction" and the Edinburgh Magazine and Literary Miscellany hoped to see "more productions ... from this author". On the other hand, John Wilson Croker, writing anonymously in the Quarterly Review, although conceding that "the author has powers, both of conception and language," described the book as "a tissue of horrible and disgusting absurdity."

In two other reviews where the author is known as the daughter of William Godwin, the criticism of the novel makes reference to the feminine nature of Mary Shelley. The British Critic attacks the novel's flaws as the fault of the author: "The writer of it is, we understand, a female; this is an aggravation of that which is the prevailing fault of the novel; but if our authoress can forget the gentleness of her sex, it is no reason why we should; and we shall therefore dismiss the novel without further comment". The Literary Panorama and National Register attacks the novel as a "feeble imitation of Mr. Godwin's novels" produced by the "daughter of a celebrated living novelist." Despite these reviews, Frankenstein achieved an almost immediate popular success. It became widely known, especially through melodramatic theatrical adaptations—Mary Shelley saw a production of Presumption; or The Fate of Frankenstein, a play by Richard Brinsley Peake, in 1823.

Critical reception of Frankenstein has been largely positive since the mid-20th century. Major critics such as M. A. Goldberg and Harold Bloom have praised the "aesthetic and moral" relevance of the novel, although there have also been critics, such as Germaine Greer, who criticized the novel for technical and narrative defects: for example, she claimed that its three narrators all speak in the same way. In more recent years the novel has become a popular subject for psychoanalytic and feminist criticism: Lawrence Lipking states: "[E]ven the Lacanian subgroup of psychoanalytic criticism, for instance, has produced at least half a dozen discrete readings of the novel". Frankenstein has frequently been recommended on Five Books, with literary scholars, psychologists, novelists, and historians citing it as an influential text. Today, the novel is generally considered to be a landmark work as one of the greatest Romantic and Gothic novels, as well as one of the first science fiction novels.

Brian Aldiss has argued for regarding it as the first true science-fiction story. In contrast to previous stories with fantastical elements resembling those of later science fiction, Aldiss states, the central character "makes a deliberate decision" and "turns to modern experiments in the laboratory" to achieve fantastic results.

Film director Guillermo del Toro describes Frankenstein as "the quintessential teenage book", noting that the feelings that "You don't belong. You were brought to this world by people that don't care for you and you are thrown into a world of pain and suffering, and tears and hunger" are an important part of the story. He adds that "it's an amazing book written by a teenage girl. It's mind-blowing." Professor of philosophy Patricia MacCormack says that the Creature addresses the most fundamental human questions: "It's the idea of asking your maker what your purpose is. Why are we here, what can we do?"

On 5 November 2019, BBC News included Frankenstein in its list of the 100 most influential novels. In 2021 it was one of six classic science fiction novels by British authors selected by Royal Mail to be featured on a series of UK postage stamps.

Electricity

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Electricity
Lighting strikes on a city at night
Lightning (pictured) and urban lighting are some of the most dramatic effects of electricity

Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell's equations. Common phenomena are related to electricity, including lightning, static electricity, electric heating, electric discharges and many others.

The presence of either a positive or negative electric charge produces an electric field. The motion of electric charges is an electric current and produces a magnetic field. In most applications, Coulomb's law determines the force acting on an electric charge. Electric potential is the work done to move an electric charge from one point to another within an electric field, typically measured in volts.

Electricity plays a central role in many modern technologies, serving in electric power where electric current is used to energise equipment, and in electronics dealing with electrical circuits involving active components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies.

The study of electrical phenomena dates back to antiquity, with theoretical understanding progressing slowly until the 17th and 18th centuries. The development of the theory of electromagnetism in the 19th century marked significant progress, leading to electricity's industrial and residential application by electrical engineers by the century's end. This rapid expansion in electrical technology at the time was the driving force behind the Second Industrial Revolution, with electricity's versatility driving transformations in both industry and society. Electricity is integral to applications spanning transport, heating, lighting, communications, and computation, making it the foundation of modern industrial society.

History

A bust of a bearded man with dishevelled hair
Thales, the earliest known researcher into electricity

Long before any knowledge of electricity existed, people were aware of shocks from electric fish. Ancient Egyptian texts dating from 2750 BCE described them as the "protectors" of all other fish. Electric fish were again reported millennia later by ancient Greek, Roman and Arabic naturalists and physicians. Several ancient writers, such as Pliny the Elder and Scribonius Largus, attested to the numbing effect of electric shocks delivered by electric catfish and electric rays, and knew that such shocks could travel along conducting objects. Patients with ailments such as gout or headache were directed to touch electric fish in the hope that the powerful jolt might cure them.

Ancient cultures around the Mediterranean knew that certain objects, such as rods of amber, could be rubbed with cat's fur to attract light objects like feathers. Thales of Miletus made a series of observations on static electricity around 600 BCE, from which he believed that friction rendered amber magnetic, in contrast to minerals such as magnetite, which needed no rubbing. Thales was incorrect in believing the attraction was due to a magnetic effect, but later science would prove a link between magnetism and electricity. According to a controversial theory, the Parthians may have had knowledge of electroplating, based on the 1936 discovery of the Baghdad Battery, which resembles a galvanic cell, though it is uncertain whether the artifact was electrical in nature.

A half-length portrait of a bald, somewhat portly man in a three-piece suit.
Benjamin Franklin conducted extensive research on electricity in the 18th century, as documented by Joseph Priestley (1767) History and Present Status of Electricity, with whom Franklin carried on extended correspondence.

Electricity would remain little more than an intellectual curiosity for millennia until 1600, when the English scientist William Gilbert wrote De Magnete, in which he made a careful study of electricity and magnetism, distinguishing the lodestone effect from static electricity produced by rubbing amber. He coined the Neo-Latin word electricus ("of amber" or "like amber", from ἤλεκτρον, elektron, the Greek word for "amber") to refer to the property of attracting small objects after being rubbed. This association gave rise to the English words "electric" and "electricity", which made their first appearance in print in Thomas Browne's Pseudodoxia Epidemica of 1646.

Further work was conducted in the 17th and early 18th centuries by Otto von Guericke, Robert Boyle, Stephen Gray and C. F. du Fay. Later in the 18th century, Benjamin Franklin conducted extensive research in electricity, selling his possessions to fund his work. In June 1752 he is reputed to have attached a metal key to the bottom of a dampened kite string and flown the kite in a storm-threatened sky. A succession of sparks jumping from the key to the back of his hand showed that lightning was indeed electrical in nature. He also explained the apparently paradoxical behavior of the Leyden jar as a device for storing large amounts of electrical charge in terms of electricity consisting of both positive and negative charges.

Half-length portrait oil painting of a man in a dark suit
Michael Faraday's discoveries formed the foundation of electric motor technology.

In 1775, Hugh Williamson reported a series of experiments to the Royal Society on the shocks delivered by the electric eel; that same year the surgeon and anatomist John Hunter described the structure of the fish's electric organs. In 1791, Luigi Galvani published his discovery of bioelectromagnetics, demonstrating that electricity was the medium by which neurons passed signals to the muscles. Alessandro Volta's battery, or voltaic pile, of 1800, made from alternating layers of zinc and copper, provided scientists with a more reliable source of electrical energy than the electrostatic machines previously used. The recognition of electromagnetism, the unity of electric and magnetic phenomena, is due to Hans Christian Ørsted and André-Marie Ampère in 1819–1820. Michael Faraday invented the electric motor in 1821, and Georg Ohm mathematically analysed the electrical circuit in 1827. Electricity and magnetism (and light) were definitively linked by James Clerk Maxwell, in particular in his "On Physical Lines of Force" in 1861 and 1862.

While the early 19th century had seen rapid progress in electrical science, the late 19th century would see the greatest progress in electrical engineering. Through such people as Alexander Graham Bell, Ottó Bláthy, Thomas Edison, Galileo Ferraris, Oliver Heaviside, Ányos Jedlik, William Thomson, 1st Baron Kelvin, Charles Algernon Parsons, Werner von Siemens, Joseph Swan, Reginald Fessenden, Nikola Tesla and George Westinghouse, electricity turned from a scientific curiosity into an essential tool for modern life.

In 1887, Heinrich Hertz discovered that electrodes illuminated with ultraviolet light create electric sparks more easily. In 1905, Albert Einstein published a paper that explained experimental data from the photoelectric effect as being the result of light energy being carried in discrete quantized packets, energising electrons. This discovery led to the quantum revolution. Einstein was awarded the Nobel Prize in Physics in 1921 for "his discovery of the law of the photoelectric effect". The photoelectric effect is also employed in photocells such as can be found in solar panels.

The first solid-state device was the "cat's-whisker detector" first used in the 1900s in radio receivers. A whisker-like wire is placed lightly in contact with a solid crystal (such as a germanium crystal) to detect a radio signal by the contact junction effect. In a solid-state component, the current is confined to solid elements and compounds engineered specifically to switch and amplify it. Current flow can be understood in two forms: as negatively charged electrons, and as positively charged electron deficiencies called holes. These charges and holes are understood in terms of quantum physics. The building material is most often a crystalline semiconductor.

Solid-state electronics came into its own with the emergence of transistor technology. The first working transistor, a germanium-based point-contact transistor, was invented by John Bardeen and Walter Houser Brattain at Bell Labs in 1947, followed by the bipolar junction transistor in 1948.

Concepts

Electric charge

A clear glass dome has an external electrode which connects through the glass to a pair of gold leaves. A charged rod touches the external electrode and makes the leaves repel.
Charge on a gold-leaf electroscope causes the leaves to visibly repel each other

By modern convention, the charge carried by electrons is defined as negative, and that by protons is positive. Before these particles were discovered, Benjamin Franklin had defined a positive charge as being the charge acquired by a glass rod when it is rubbed with a silk cloth. A proton by definition carries a charge of exactly 1.602176634×10−19 coulombs. This value is also defined as the elementary charge. No object can have a charge smaller than the elementary charge, and any amount of charge an object may carry is a multiple of the elementary charge. An electron has an equal negative charge, i.e. −1.602176634×10−19 coulombs. Charge is possessed not just by matter, but also by antimatter, each antiparticle bearing an equal and opposite charge to its corresponding particle.

The presence of charge gives rise to an electrostatic force: charges exert a force on each other, an effect that was known, though not understood, in antiquity. A lightweight ball suspended by a fine thread can be charged by touching it with a glass rod that has itself been charged by rubbing with a cloth. If a similar ball is charged by the same glass rod, it is found to repel the first: the charge acts to force the two balls apart. Two balls that are charged with a rubbed amber rod also repel each other. However, if one ball is charged by the glass rod, and the other by an amber rod, the two balls are found to attract each other. These phenomena were investigated in the late eighteenth century by Charles-Augustin de Coulomb, who deduced that charge manifests itself in two opposing forms. This discovery led to the well-known axiom: like-charged objects repel and opposite-charged objects attract.

The force acts on the charged particles themselves, hence charge has a tendency to spread itself as evenly as possible over a conducting surface. The magnitude of the electromagnetic force, whether attractive or repulsive, is given by Coulomb's law, which relates the force to the product of the charges and has an inverse-square relation to the distance between them. The electromagnetic force is very strong, second only in strength to the strong interaction, but unlike that force it operates over all distances. In comparison with the much weaker gravitational force, the electromagnetic force pushing two electrons apart is 1042 times that of the gravitational attraction pulling them together.

Charge originates from certain types of subatomic particles, the most familiar carriers of which are the electron and proton. Electric charge gives rise to and interacts with the electromagnetic force, one of the four fundamental forces of nature. Experiment has shown charge to be a conserved quantity, that is, the net charge within an electrically isolated system will always remain constant regardless of any changes taking place within that system. Within the system, charge may be transferred between bodies, either by direct contact, or by passing along a conducting material, such as a wire. The informal term static electricity refers to the net presence (or 'imbalance') of charge on a body, usually caused when dissimilar materials are rubbed together, transferring charge from one to the other.

Charge can be measured by a number of means, an early instrument being the gold-leaf electroscope, which although still in use for classroom demonstrations, has been superseded by the electronic electrometer.

Electric current

The movement of electric charge is known as an electric current, the intensity of which is usually measured in amperes. Current can consist of any moving charged particles; most commonly these are electrons, but any charge in motion constitutes a current. Electric current can flow through some things, electrical conductors, but will not flow through an electrical insulator.

By historical convention, a positive current is defined as having the same direction of flow as any positive charge it contains, or to flow from the most positive part of a circuit to the most negative part. Current defined in this manner is called conventional current. The motion of negatively charged electrons around an electric circuit, one of the most familiar forms of current, is thus deemed positive in the opposite direction to that of the electrons. However, depending on the conditions, an electric current can consist of a flow of charged particles in either direction, or even in both directions at once. The positive-to-negative convention is widely used to simplify this situation.

Two metal wires form an inverted V shape. A blindingly bright orange-white electric arc flows between their tips.
An electric arc provides an energetic demonstration of electric current.

The process by which electric current passes through a material is termed electrical conduction, and its nature varies with that of the charged particles and the material through which they are travelling. Examples of electric currents include metallic conduction, where electrons flow through a conductor such as metal, and electrolysis, where ions (charged atoms) flow through liquids, or through plasmas such as electrical sparks. While the particles themselves can move quite slowly, sometimes with an average drift velocity only fractions of a millimetre per second, the electric field that drives them itself propagates at close to the speed of light, enabling electrical signals to pass rapidly along wires.

Current causes several observable effects, which historically were the means of recognising its presence. That water could be decomposed by the current from a voltaic pile was discovered by Nicholson and Carlisle in 1800, a process now known as electrolysis. Their work was greatly expanded upon by Michael Faraday in 1833. Current through a resistance causes localised heating, an effect James Prescott Joule studied mathematically in 1840. One of the most important discoveries relating to current was made accidentally by Hans Christian Ørsted in 1820, when, while preparing a lecture, he witnessed the current in a wire disturbing the needle of a magnetic compass. He had discovered electromagnetism, a fundamental interaction between electricity and magnetics. The level of electromagnetic emissions generated by electric arcing is high enough to produce electromagnetic interference, which can be detrimental to the workings of adjacent equipment.

In engineering or household applications, current is often described as being either direct current (DC) or alternating current (AC). These terms refer to how the current varies in time. Direct current, as produced by example from a battery and required by most electronic devices, is a unidirectional flow from the positive part of a circuit to the negative. If, as is most common, this flow is carried by electrons, they will be travelling in the opposite direction. Alternating current is any current that reverses direction repeatedly; almost always this takes the form of a sine wave. Alternating current thus pulses back and forth within a conductor without the charge moving any net distance over time. The time-averaged value of an alternating current is zero, but it delivers energy in first one direction, and then the reverse. Alternating current is affected by electrical properties that are not observed under steady state direct current, such as inductance and capacitance. These properties however can become important when circuitry is subjected to transients, such as when first energised.

Electric field

The concept of the electric field was introduced by Michael Faraday. An electric field is created by a charged body in the space that surrounds it, and results in a force exerted on any other charges placed within the field. The electric field acts between two charges in a similar manner to the way that the gravitational field acts between two masses, and like it, extends towards infinity and shows an inverse square relationship with distance. However, there is an important difference. Gravity always acts in attraction, drawing two masses together, while the electric field can result in either attraction or repulsion. Since large bodies such as planets generally carry no net charge, the electric field at a distance is usually zero. Thus gravity is the dominant force at distance in the universe, despite being much weaker.

Field lines emanating from a positive charge above a plane conductor

An electric field generally varies in space, and its strength at any one point is defined as the force (per unit charge) that would be felt by a stationary, negligible charge if placed at that point. The conceptual charge, termed a 'test charge', must be vanishingly small to prevent its own electric field disturbing the main field and must also be stationary to prevent the effect of magnetic fields. As the electric field is defined in terms of force, and force is a vector, having both magnitude and direction, it follows that an electric field is a vector field.

The study of electric fields created by stationary charges is called electrostatics. The field may be visualised by a set of imaginary lines whose direction at any point is the same as that of the field. This concept was introduced by Faraday, whose term 'lines of force' still sometimes sees use. The field lines are the paths that a point positive charge would seek to make as it was forced to move within the field; they are however an imaginary concept with no physical existence, and the field permeates all the intervening space between the lines. Field lines emanating from stationary charges have several key properties: first, that they originate at positive charges and terminate at negative charges; second, that they must enter any good conductor at right angles, and third, that they may never cross nor close in on themselves.

A hollow conducting body carries all its charge on its outer surface. The field is therefore 0 at all places inside the body. This is the operating principal of the Faraday cage, a conducting metal shell which isolates its interior from outside electrical effects.

The principles of electrostatics are important when designing items of high-voltage equipment. There is a finite limit to the electric field strength that may be withstood by any medium. Beyond this point, electrical breakdown occurs and an electric arc causes flashover between the charged parts. Air, for example, tends to arc across small gaps at electric field strengths which exceed 30 kV per centimetre. Over larger gaps, its breakdown strength is weaker, perhaps 1 kV per centimetre. The most visible natural occurrence of this is lightning, caused when charge becomes separated in the clouds by rising columns of air, and raises the electric field in the air to greater than it can withstand. The voltage of a large lightning cloud may be as high as 100 MV and have discharge energies as great as 250 kWh.

The field strength is greatly affected by nearby conducting objects, and it is particularly intense when it is forced to curve around sharply pointed objects. This principle is exploited in the lightning conductor, the sharp spike of which acts to encourage the lightning strike to develop there, rather than to the building it serves to protect.

Electric potential

Two AA batteries each have a plus sign marked at one end.
A pair of AA cells. The + sign indicates the polarity of the potential difference between the battery terminals.

The concept of electric potential is closely linked to that of the electric field. A small charge placed within an electric field experiences a force, and to have brought that charge to that point against the force requires work. The electric potential at any point is defined as the energy required to bring a unit test charge from an infinite distance slowly to that point. It is usually measured in volts, and one volt is the potential for which one joule of work must be expended to bring a charge of one coulomb from infinity. This definition of potential, while formal, has little practical application, and a more useful concept is that of electric potential difference, and is the energy required to move a unit charge between two specified points. An electric field has the special property that it is conservative, which means that the path taken by the test charge is irrelevant: all paths between two specified points expend the same energy, and thus a unique value for potential difference may be stated. The volt is so strongly identified as the unit of choice for measurement and description of electric potential difference that the term voltage sees greater everyday usage.

For practical purposes, defining a common reference point to which potentials may be expressed and compared is useful. While this could be at infinity, a much more useful reference is the Earth itself, which is assumed to be at the same potential everywhere. This reference point naturally takes the name earth or ground. Earth is assumed to be an infinite source of equal amounts of positive and negative charge and is therefore electrically uncharged—and unchargeable.

Electric potential is a scalar quantity. That is, it has only magnitude and not direction. It may be viewed as analogous to height: just as a released object will fall through a difference in heights caused by a gravitational field, so a charge will 'fall' across the voltage caused by an electric field. As relief maps show contour lines marking points of equal height, a set of lines marking points of equal potential (known as equipotentials) may be drawn around an electrostatically charged object. The equipotentials cross all lines of force at right angles. They must also lie parallel to a conductor's surface, since otherwise there would be a force along the surface of the conductor that would move the charge carriers to even the potential across the surface.

The electric field was formally defined as the force exerted per unit charge, but the concept of potential allows for a more useful and equivalent definition: the electric field is the local gradient of the electric potential. Usually expressed in volts per metre, the vector direction of the field is the line of greatest slope of potential, and where the equipotentials lie closest together.

Electromagnets

A wire carries a current towards the reader. Concentric circles representing the magnetic field circle anticlockwise around the wire, as viewed by the reader.
Magnetic field circles around a current

Ørsted's discovery in 1821 that a magnetic field existed around all sides of a wire carrying an electric current indicated that there was a direct relationship between electricity and magnetism. Moreover, the interaction seemed different from gravitational and electrostatic forces, the two forces of nature then known. The force on the compass needle did not direct it to or away from the current-carrying wire, but acted at right angles to it. Ørsted's words were that "the electric conflict acts in a revolving manner." The force also depended on the direction of the current, for if the flow was reversed, then the force did too.

Ørsted did not fully understand his discovery, but he observed the effect was reciprocal: a current exerts a force on a magnet, and a magnetic field exerts a force on a current. The phenomenon was further investigated by Ampère, who discovered that two parallel current-carrying wires exerted a force upon each other: two wires conducting currents in the same direction are attracted to each other, while wires containing currents in opposite directions are forced apart. The interaction is mediated by the magnetic field each current produces and forms the basis for the international definition of the ampere.

A cut-away diagram of a small electric motor
The electric motor exploits an important effect of electromagnetism: a current through a magnetic field experiences a force at right angles to both the field and current.

This relationship between magnetic fields and currents is extremely important, for it led to Michael Faraday's invention of the electric motor in 1821. Faraday's homopolar motor consisted of a permanent magnet sitting in a pool of mercury. A current was allowed through a wire suspended from a pivot above the magnet and dipped into the mercury. The magnet exerted a tangential force on the wire, making it circle around the magnet for as long as the current was maintained.

Experimentation by Faraday in 1831 revealed that a wire moving perpendicular to a magnetic field developed a potential difference between its ends. Further analysis of this process, known as electromagnetic induction, enabled him to state the principle, now known as Faraday's law of induction, that the potential difference induced in a closed circuit is proportional to the rate of change of magnetic flux through the loop. Exploitation of this discovery enabled him to invent the first electrical generator in 1831, in which he converted the mechanical energy of a rotating copper disc to electrical energy. Faraday's disc was inefficient and of no use as a practical generator, but it showed the possibility of generating electric power using magnetism, a possibility that would be taken up by those that followed on from his work.

Electric circuits

refer to caption
A basic electric circuit. The voltage source V on the left drives a current I around the circuit, delivering electrical energy into the resistor R. From the resistor, the current returns to the source, completing the circuit.

An electric circuit is an interconnection of electric components such that electric charge is made to flow along a closed path (a circuit), usually to perform some useful task.

The components in an electric circuit can take many forms, which can include elements such as resistors, capacitors, switches, transformers and electronics. Electronic circuits contain active components, usually semiconductors, and typically exhibit non-linear behaviour, requiring complex analysis. The simplest electric components are those that are termed passive and linear: while they may temporarily store energy, they contain no sources of it, and exhibit linear responses to stimuli.

The resistor is perhaps the simplest of passive circuit elements: as its name suggests, it resists the current through it, dissipating its energy as heat. The resistance is a consequence of the motion of charge through a conductor: in metals, for example, resistance is primarily due to collisions between electrons and ions. Ohm's law is a basic law of circuit theory, stating that the current passing through a resistance is directly proportional to the potential difference across it. The resistance of most materials is relatively constant over a range of temperatures and currents; materials under these conditions are known as 'ohmic'. The ohm, the unit of resistance, was named in honour of Georg Ohm, and is symbolised by the Greek letter Ω. 1 Ω is the resistance that will produce a potential difference of one volt in response to a current of one amp.

The capacitor is a development of the Leyden jar and is a device that can store charge, and thereby storing electrical energy in the resulting field. It consists of two conducting plates separated by a thin insulating dielectric layer; in practice, thin metal foils are coiled together, increasing the surface area per unit volume and therefore the capacitance. The unit of capacitance is the farad, named after Michael Faraday, and given the symbol F: one farad is the capacitance that develops a potential difference of one volt when it stores a charge of one coulomb. A capacitor connected to a voltage supply initially causes a current as it accumulates charge; this current will however decay in time as the capacitor fills, eventually falling to zero. A capacitor will therefore not permit a steady state current, but instead blocks it.

The inductor is a conductor, usually a coil of wire, that stores energy in a magnetic field in response to the current through it. When the current changes, the magnetic field does too, inducing a voltage between the ends of the conductor. The induced voltage is proportional to the time rate of change of the current. The constant of proportionality is termed the inductance. The unit of inductance is the henry, named after Joseph Henry, a contemporary of Faraday. One henry is the inductance that will induce a potential difference of one volt if the current through it changes at a rate of one ampere per second. The inductor's behaviour is in some regards converse to that of the capacitor: it will freely allow an unchanging current, but opposes a rapidly changing one.

Electric power

Electric power is the rate at which electric energy is transferred by an electric circuit. The SI unit of power is the watt, one joule per second.

Electric power, like mechanical power, is the rate of doing work, measured in watts, and represented by the letter P. The term wattage is used colloquially to mean "electric power in watts." The electric power in watts produced by an electric current I consisting of a charge of Q coulombs every t seconds passing through an electric potential (voltage) difference of V is

where

Q is electric charge in coulombs
t is time in seconds
I is electric current in amperes
V is electric potential or voltage in volts

Electric power is generally supplied to businesses and homes by the electric power industry. Electricity is usually sold by the kilowatt hour (3.6 MJ) which is the product of power in kilowatts multiplied by running time in hours. Electric utilities measure power using electricity meters, which keep a running total of the electric energy delivered to a customer. Unlike fossil fuels, electricity is a low entropy form of energy and can be converted into motion or many other forms of energy with high efficiency.

Electronics

Surface-mount electronic components

Electronics deals with electrical circuits that involve active electrical components such as vacuum tubes, transistors, diodes, sensors and integrated circuits, and associated passive interconnection technologies. The nonlinear behaviour of active components and their ability to control electron flows makes digital switching possible, and electronics is widely used in information processing, telecommunications, and signal processing. Interconnection technologies such as circuit boards, electronics packaging technology, and other varied forms of communication infrastructure complete circuit functionality and transform the mixed components into a regular working system.

Today, most electronic devices use semiconductor components to perform electron control. The underlying principles that explain how semiconductors work are studied in solid state physics, whereas the design and construction of electronic circuits to solve practical problems are part of electronics engineering.

Electromagnetic wave

Faraday's and Ampère's work showed that a time-varying magnetic field created an electric field, and a time-varying electric field created a magnetic field. Thus, when either field is changing in time, a field of the other is always induced. These variations are an electromagnetic wave. Electromagnetic waves were analysed theoretically by James Clerk Maxwell in 1864. Maxwell developed a set of equations that could unambiguously describe the interrelationship between electric field, magnetic field, electric charge, and electric current. He could moreover prove that in a vacuum such a wave would travel at the speed of light, and thus light itself was a form of electromagnetic radiation. Maxwell's equations, which unify light, fields, and charge are one of the great milestones of theoretical physics.

The work of many researchers enabled the use of electronics to convert signals into high frequency oscillating currents and, via suitably shaped conductors, electricity permits the transmission and reception of these signals via radio waves over very long distances.

Production, storage and uses

Generation and transmission

Early 20th-century alternator made in Budapest, Hungary, in the power generating hall of a hydroelectric station (photograph by Prokudin-Gorsky, 1905–1915).

In the 6th century BC the Greek philosopher Thales of Miletus experimented with amber rods: these were the first studies into the production of electricity. While this method, now known as the triboelectric effect, can lift light objects and generate sparks, it is extremely inefficient. It was not until the invention of the voltaic pile in the eighteenth century that a viable source of electricity became available. The voltaic pile, and its modern descendant, the electrical battery, store energy chemically and make it available on demand in the form of electricity.

Electrical power is usually generated by electro-mechanical generators. These can be driven by steam produced from fossil fuel combustion or the heat released from nuclear reactions, but also more directly from the kinetic energy of wind or flowing water. The steam turbine invented by Sir Charles Parsons in 1884 is still used to convert the thermal energy of steam into a rotary motion that can be used by electro-mechanical generators. Such generators bear no resemblance to Faraday's homopolar disc generator of 1831, but they still rely on his electromagnetic principle that a conductor linking a changing magnetic field induces a potential difference across its ends. Electricity generated by solar panels rely on a different mechanism: solar radiation is converted directly into electricity using the photovoltaic effect.

A wind farm of about a dozen three-bladed white wind turbines.
Wind power is of increasing importance in many countries.

Demand for electricity grows with great rapidity as a nation modernises and its economy develops. The United States showed a 12% increase in demand during each year of the first three decades of the twentieth century, a rate of growth that is now being experienced by emerging economies such as those of India or China.

Environmental concerns with electricity generation, in specific the contribution of fossil fuel burning to climate change, have led to an increased focus on generation from renewable sources. In the power sector, wind and solar have become cost effective, speeding up an energy transition away from fossil fuels.

Transmission and storage

The invention in the late nineteenth century of the transformer meant that electrical power could be transmitted more efficiently at a higher voltage but lower current. Efficient electrical transmission meant in turn that electricity could be generated at centralised power stations, where it benefited from economies of scale, and then be despatched relatively long distances to where it was needed.

Normally, demand of electricity must match the supply, as storage of electricity is difficult. A certain amount of generation must always be held in reserve to cushion an electrical grid against inevitable disturbances and losses. With increasing levels of variable renewable energy (wind and solar energy) in the grid, it has become more challenging to match supply and demand. Storage plays an increasing role in bridging that gap. There are four types of energy storage technologies, each in varying states of technology readiness: batteries (electrochemical storage), chemical storage such as hydrogen, thermal or mechanical (such as pumped hydropower).

Applications

a photo of a light bulb
The incandescent light bulb, an early application of electricity, operates by Joule heating: the passage of current through resistance generating heat.

Electricity is a very convenient way to transfer energy, and it has been adapted to a huge, and growing, number of uses. The invention of a practical incandescent light bulb in the 1870s led to lighting becoming one of the first publicly available applications of electrical power. Although electrification brought with it its own dangers, replacing the naked flames of gas lighting greatly reduced fire hazards within homes and factories. Public utilities were set up in many cities targeting the burgeoning market for electrical lighting. In the late 20th century and in modern times, the trend has started to flow in the direction of deregulation in the electrical power sector.

The resistive Joule heating effect employed in filament light bulbs also sees more direct use in electric heating. While this is versatile and controllable, it can be seen as wasteful, since most electrical generation has already required the production of heat at a power station. A number of countries, such as Denmark, have issued legislation restricting or banning the use of resistive electric heating in new buildings. Electricity is however still a highly practical energy source for heating and refrigeration, with air conditioning/heat pumps representing a growing sector for electricity demand for heating and cooling, the effects of which electricity utilities are increasingly obliged to accommodate. Electrification is expected to play a major role in the decarbonisation of sectors that rely on direct fossil fuel burning, such as transport (using electric vehicles) and heating (using heat pumps).

The effects of electromagnetism are most visibly employed in the electric motor, which provides a clean and efficient means of motive power. A stationary motor such as a winch is easily provided with a supply of power, but a motor that moves with its application, such as an electric vehicle, is obliged to either carry along a power source such as a battery, or to collect current from a sliding contact such as a pantograph. Electrically powered vehicles are used in public transportation, such as electric buses and trains, and an increasing number of battery-powered electric cars in private ownership.

Electricity is used within telecommunications, and indeed the electrical telegraph, demonstrated commercially in 1837 by Cooke and Wheatstone, was one of its earliest applications. With the construction of first transcontinental, and then transatlantic, telegraph systems in the 1860s, electricity had enabled communications in minutes across the globe. Optical fibre and satellite communication have taken a share of the market for communications systems, but electricity can be expected to remain an essential part of the process.

Electronic devices make use of the transistor, perhaps one of the most important inventions of the twentieth century, and a fundamental building block of all modern circuitry. A modern integrated circuit may contain many billions of miniaturised transistors in a region only a few centimetres square.

Electricity and the natural world

Physiological effects

A voltage applied to a human body causes an electric current through the tissues, and although the relationship is non-linear, the greater the voltage, the greater the current. The threshold for perception varies with the supply frequency and with the path of the current, but is about 0.1 mA to 1 mA for mains-frequency electricity, though a current as low as a microamp can be detected as an electrovibration effect under certain conditions. If the current is sufficiently high, it will cause muscle contraction, fibrillation of the heart, and tissue burns. The lack of any visible sign that a conductor is electrified makes electricity a particular hazard. The pain caused by an electric shock can be intense, leading electricity at times to be employed as a method of torture. Death caused by an electric shock—electrocution—is still used for judicial execution in some US states, though its use had become very rare by the end of the 20th century.

Electrical phenomena in nature

The electric eel, Electrophorus electricus

Electricity is not a human invention, and may be observed in several forms in nature, notably lightning. Many interactions familiar at the macroscopic level, such as touch, friction or chemical bonding, are due to interactions between electric fields on the atomic scale. The Earth's magnetic field is due to the natural dynamo of circulating currents in the planet's core. Certain crystals, such as quartz, or even sugar, generate a potential difference across their faces when pressed. This phenomenon is known as piezoelectricity, from the Greek piezein (πιέζειν), meaning to press, and was discovered in 1880 by Pierre and Jacques Curie. The effect is reciprocal: when a piezoelectric material is subjected to an electric field it changes size slightly.

Some organisms, such as sharks, are able to detect and respond to changes in electric fields, an ability known as electroreception, while others, termed electrogenic, are able to generate voltages themselves to serve as a predatory or defensive weapon; these are electric fish in different orders. The order Gymnotiformes, of which the best known example is the electric eel, detect or stun their prey via high voltages generated from modified muscle cells called electrocytes. All animals transmit information along their cell membranes with voltage pulses called action potentials, whose functions include communication by the nervous system between neurons and muscles. An electric shock stimulates this system, and causes muscles to contract. Action potentials are also responsible for coordinating activities in certain plants.

Cultural perception

It is said that in the 1850s, British politician William Ewart Gladstone asked the scientist Michael Faraday why electricity was valuable. Faraday answered, "One day sir, you may tax it." However, according to Snopes.com "the anecdote should be considered apocryphal because it isn't mentioned in any accounts by Faraday or his contemporaries (letters, newspapers, or biographies) and only popped up well after Faraday's death."

In the 19th and early 20th century, electricity was not part of the everyday life of many people, even in the industrialised Western world. The popular culture of the time accordingly often depicted it as a mysterious, quasi-magical force that can slay the living, revive the dead or otherwise bend the laws of nature. This attitude began with the 1771 experiments of Luigi Galvani in which the legs of dead frogs were shown to twitch on application of animal electricity. "Revitalization" or resuscitation of apparently dead or drowned persons was reported in the medical literature shortly after Galvani's work. These results were known to Mary Shelley when she authored Frankenstein (1819), although she does not name the method of revitalization of the monster. The revitalization of monsters with electricity later became a stock theme in horror films.

As public familiarity with electricity as the lifeblood of the Second Industrial Revolution grew, its wielders were more often cast in a positive light, such as the workers who "finger death at their gloves' end as they piece and repiece the living wires" in Rudyard Kipling's 1907 poem Sons of Martha. Electrically powered vehicles of every sort featured large in adventure stories such as those of Jules Verne and the Tom Swift books. The masters of electricity, whether fictional or real—including scientists such as Thomas Edison, Charles Steinmetz or Nikola Tesla—were popularly conceived of as having wizard-like powers.

With electricity ceasing to be a novelty and becoming a necessity of everyday life in the later half of the 20th century, it acquired particular attention by popular culture only when it stops flowing, an event that usually signals disaster. The people who keep it flowing, such as the nameless hero of Jimmy Webb's song "Wichita Lineman" (1968), are still often cast as heroic, wizard-like figures.

Neurophilosophy

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