Supreme Court of California
The Supreme Court of California is the highest and final court in the courts of the State of California. It resides in the State Building in San Francisco in Civic Center overlooking Civic Center Square along with City Hall, it holds sessions in Los Angeles and Sacramento. Its decisions are binding on all other California state courts. Under the original 1849 California Constitution, the Court started with a chief justice and two associate justices; the Court was expanded to five justices in 1862. Under the current 1879 constitution, the Court expanded to six associate justices and one chief justice, for the current total of seven; the justices are subject to retention elections. According to the California Constitution, to be considered for appointment, as with any California judge, a person must be an attorney admitted to practice in California or have served as a judge of a California court for 10 years preceding the appointment. To fill a vacant position, the Governor must first submit a candidate's name to the Commission on Judicial Nominees Evaluation of the State Bar of California, which prepares and returns a thorough, confidential evaluation of the candidate.
Next, the Governor nominates the candidate, who must be evaluated by the Commission on Judicial Appointments, which consists of the Chief Justice of California, the Attorney General of California, a senior presiding justice of the California Courts of Appeal. The Commission holds a public hearing and if satisfied with the nominee's qualifications, confirms the nomination; the nominee can immediately fill an existing vacancy, or replace a departing justice at the beginning of the next judicial term. If a nominee is confirmed to fill a vacancy that arose partway through a judicial term, the justice must stand for retention during the next gubernatorial election. Voters determine whether to retain the justice for the remainder of the judicial term. At the term's conclusion, justices must again undergo a statewide retention election for a full 12-year term. If a majority votes "no," the seat may be filled by the Governor; the electorate has exercised the power not to retain justices. Chief Justice Rose Bird and Associate Justices Cruz Reynoso and Joseph Grodin were staunchly opposed to capital punishment and were subsequently removed in the 1986 general election.
Newly reelected Governor George Deukmejian was able to elevate Associate Justice Malcolm M. Lucas to Chief Justice and appoint three new associate justices. Four current justices were appointed by three by Republicans. There is one Filipino-American justice, one Hispanic, one African-American, two East Asian-American justices, two non-Hispanic white justices; the justices do not publicly discuss their religious views or affiliations. One justice earned an undergraduate degree from a University of California school, four from private universities in California, two from out-of-state private universities. Two justices earned their law degrees from a University of California law school, one from a law school at a California private university, four from law schools at out-of-state private universities; the most recent addition to the court is Associate Justice Joshua Groban, replacing Associate Justice Kathryn M. Werdegar, who retired on August 31, 2017. Governor Jerry Brown nominated Groban on November 14, 2018.
He joined the court when it reconvened on January 8. Between 1879 and 1966, the court was divided into two three-justice panels, Department One and Department Two; the chief justice divided cases evenly between the panels and decided which cases would be heard en banc by the Court sitting as a whole. After a constitutional amendment in 1966, the Court sits "in bank" when hearing all appeals; when there is an open seat on the court, or if a justice recuses himself or herself on a given case, justices from the California Courts of Appeal are assigned by the chief justice to join the court for individual cases on a rotational basis. The procedure for when all justices recuse themselves from a case has varied over time. For a 1992 case, the chief justice requested the presiding justice of a Court of Appeal district to select six other Court of Appeal justices from his district, they formed an acting Supreme Court for the purpose of deciding that one case. However, in a case where all members of the Court recused themselves when Governor Schwarzenegger sought a writ of mandate, seven justices of the Courts of Appeal were selected based on the regular rotational basis, not from the same district, with the most senior one serving as the acting chief justice, that acting supreme court denied the writ petition.
In a yet more recent case where all members of the Court recused themselves on a petition for review by retired Court of Appeal justices on a matter involving those justices' salaries, the Court ordered that six superior court judges be selected from the pool that took office after July 1, 2017 to serve as the substitute justices for the six sitting justices, with the senior judge among that group serving as the acting Chief Justice.
Los Angeles the City of Los Angeles and known by its initials L. A. is the most populous city in California, the second most populous city in the United States, after New York City, the third most populous city in North America. With an estimated population of four million, Los Angeles is the cultural and commercial center of Southern California; the city is known for its Mediterranean climate, ethnic diversity and the entertainment industry, its sprawling metropolis. Los Angeles is the largest city on the West Coast of North America. Los Angeles is in a large basin bounded by the Pacific Ocean on one side and by mountains as high as 10,000 feet on the other; the city proper, which covers about 469 square miles, is the seat of Los Angeles County, the most populated county in the country. Los Angeles is the principal city of the Los Angeles metropolitan area, the second largest in the United States after that of New York City, with a population of 13.1 million. It is part of the Los Angeles-Long Beach combined statistical area the nation's second most populous area with a 2015 estimated population of 18.7 million.
Los Angeles is one of the most substantial economic engines within the United States, with a diverse economy in a broad range of professional and cultural fields. Los Angeles is famous as the home of Hollywood, a major center of the world entertainment industry. A global city, it has been ranked 6th in the Global Cities Index and 9th in the Global Economic Power Index; the Los Angeles metropolitan area has a gross metropolitan product of $1.044 trillion, making it the third-largest in the world, after the Tokyo and New York metropolitan areas. Los Angeles hosted the 1932 and 1984 Summer Olympics and will host the event for a third time in 2028; the city hosted the Miss Universe pageant twice, in 1990 and 2006, was one of 9 American cities to host the 1994 FIFA men's soccer World Cup and one of 8 to host the 1999 FIFA women's soccer World Cup, hosting the final match for both tournaments. Home to the Chumash and Tongva, Los Angeles was claimed by Juan Rodríguez Cabrillo for Spain in 1542 along with the rest of what would become Alta California.
The city was founded on September 4, 1781, by Spanish governor Felipe de Neve. It became a part of Mexico in 1821 following the Mexican War of Independence. In 1848, at the end of the Mexican–American War, Los Angeles and the rest of California were purchased as part of the Treaty of Guadalupe Hidalgo, becoming part of the United States. Los Angeles was incorporated as a municipality on April 4, 1850, five months before California achieved statehood; the discovery of oil in the 1890s brought rapid growth to the city. The completion of the Los Angeles Aqueduct in 1913, delivering water from Eastern California assured the city's continued rapid growth; the Los Angeles coastal area was settled by the Chumash tribes. A Gabrieleño settlement in the area was called iyáangẚ, meaning "poison oak place". Maritime explorer Juan Rodríguez Cabrillo claimed the area of southern California for the Spanish Empire in 1542 while on an official military exploring expedition moving north along the Pacific coast from earlier colonizing bases of New Spain in Central and South America.
Gaspar de Portolà and Franciscan missionary Juan Crespí, reached the present site of Los Angeles on August 2, 1769. In 1771, Franciscan friar Junípero Serra directed the building of the Mission San Gabriel Arcángel, the first mission in the area. On September 4, 1781, a group of forty-four settlers known as "Los Pobladores" founded the pueblo they called El Pueblo de Nuestra Señora la Reina de los Ángeles,'The Town of Our Lady the Queen of the Angels'; the present-day city has the largest Roman Catholic Archdiocese in the United States. Two-thirds of the Mexican or settlers were mestizo or mulatto, a mixture of African and European ancestry; the settlement remained a small ranch town for decades, but by 1820, the population had increased to about 650 residents. Today, the pueblo is commemorated in the historic district of Los Angeles Pueblo Plaza and Olvera Street, the oldest part of Los Angeles. New Spain achieved its independence from the Spanish Empire in 1821, the pueblo continued as a part of Mexico.
During Mexican rule, Governor Pío Pico made Los Angeles Alta California's regional capital. Mexican rule ended during the Mexican–American War: Americans took control from the Californios after a series of battles, culminating with the signing of the Treaty of Cahuenga on January 13, 1847. Railroads arrived with the completion of the transcontinental Southern Pacific line to Los Angeles in 1876 and the Santa Fe Railroad in 1885. Petroleum was discovered in the city and surrounding area in 1892, by 1923, the discoveries had helped California become the country's largest oil producer, accounting for about one-quarter of the world's petroleum output. By 1900, the population had grown to more than 102,000; the completion of the Los Angeles Aqueduct in 1913, under the supervision of William Mulholland, assured the continued growth of the city. Due to clauses in the city's charter that prevented the City of Los Angeles from selling or providing water from the aqueduct to any area outside its borders, many adjacent city and communities became compelled to annex themselves into Los Angeles.
Los Angeles created the first municipal zoning ordinance in the United States. On September 14, 1908, the Los Angeles City Council promulgated residential and industrial land use zones; the new ordinance established three residential zones of a single type, where industrial uses were
A strain gauge is a device used to measure strain on an object. Invented by Edward E. Simmons and Arthur C. Ruge in 1938, the most common type of strain gauge consists of an insulating flexible backing which supports a metallic foil pattern; the gauge is attached to the object by a suitable adhesive, such as cyanoacrylate. As the object is deformed, the foil is deformed, causing its electrical resistance to change; this resistance change measured using a Wheatstone bridge, is related to the strain by the quantity known as the gauge factor. A strain gauge takes advantage of the physical property of electrical conductance and its dependence on the conductor's geometry; when an electrical conductor is stretched within the limits of its elasticity such that it does not break or permanently deform, it will become narrower and longer, which increases its electrical resistance end-to-end. Conversely, when a conductor is compressed such that it does not buckle, it will broaden and shorten, which decreases its electrical resistance end-to-end.
From the measured electrical resistance of the strain gauge, the amount of induced stress may be inferred. A typical strain gauge arranges a long, thin conductive strip in a zig-zag pattern of parallel lines; this does not increase the sensitivity, since the percentage change in resistance for a given strain for the entire zig-zag is the same as for any single trace. A single linear trace would have to be thin, hence liable to overheating, or would need to be operated at a much lower voltage, making it difficult to measure resistance changes accurately; the gauge factor G F is defined as: G F = Δ R / R G ϵ where Δ R is the change in resistance caused by strain, R G is the resistance of the undeformed gauge, ϵ is strain. For common metallic foil gauges, the gauge factor is a little over 2. For a single active gauge and three dummy resistors of the same resistance about the active gauge in a balanced Wheatstone bridge configuration, the output sensor voltage S V from the bridge is approximately: S V = E V G F ⋅ ϵ 4 where E V is the bridge excitation voltage.
Foil gauges have active areas of about 2–10 mm2 in size. With careful installation, the correct gauge, the correct adhesive, strains up to at least 10% can be measured. An excitation voltage is applied to input leads of the gauge network, a voltage reading is taken from the output leads. Typical input voltages are 5 V or 12 V and typical output readings are in millivolts. Foil strain gauges are used in many situations. Different applications place different requirements on the gauge. In most cases the orientation of the strain gauge is significant. Gauges attached to a load cell would be expected to remain stable over a period of years, if not decades. Strain gauges are attached to the substrate with a special glue; the type of glue depends on the required lifetime of the measurement system. For short term measurements cyanoacrylate glue is appropriate, for long lasting installation epoxy glue is required. Epoxy glue requires high temperature curing; the preparation of the surface where the strain gauge is to be glued is of the utmost importance.
The surface must be smoothed, deoiled with solvents, the solvent traces must be removed and the strain gauge must be glued after this to avoid oxidation or pollution of the prepared area. If these steps are not followed the strain gauge binding to the surface may be unreliable and unpredictable measurement errors may be generated. Strain gauge based technology is utilized in the manufacture of pressure sensors; the gauges used in pressure sensors themselves are made from silicon, metal film, thick film, bonded foil. Variations in temperature will cause a multitude of effects; the object will change in size by thermal expansion, which will be detected as a strain by the gauge. Resistance of the gauge will change, resistance of the connecting wires will change. Most strain gauges are made from a constantan alloy. Various constantan alloys and Karma alloys have been designed so that the temperature effects on the resistance of the strain gauge itself cancel out the resistance change of the gauge due to the thermal expansion of the object under test.
Because different materials have different amounts of thermal expansion, self-temperature compensation requires selecting a particular alloy matched to the material of the object under test. Strain gauges that are not self-temperature-compensated can be temperature compensated by use of the dummy gauge technique. A dummy gauge is installed on an unstrained sample of the same material as the test specimen; the sample with the dummy gauge is placed in thermal contact with the test specimen, adjacent to the active gauge. The dummy gauge is wired into a Wheatstone bridge on an adjacent arm to the active gaug
Robert Andrews Millikan
Robert Andrews Millikan was an American experimental physicist honored with the Nobel Prize for Physics in 1923 for the measurement of the elementary electric charge and for his work on the photoelectric effect. Millikan graduated from Oberlin College in 1891 and obtained his doctorate at Columbia University in 1895. In 1896 he became an assistant at the University of Chicago, where he became a full professor in 1910. In 1909 Millikan began a series of experiments to determine the electric charge carried by a single electron, he began by measuring the course of charged water droplets in an electric field. The results suggested that the charge on the droplets is a multiple of the elementary electric charge, but the experiment was not accurate enough to be convincing, he obtained more precise results in 1910 with his famous oil-drop experiment in which he replaced water with oil. In 1914 Millikan took up with similar skill the experimental verification of the equation introduced by Albert Einstein in 1905 to describe the photoelectric effect.
He used this same research to obtain an accurate value of Planck’s constant. In 1921 Millikan left the University of Chicago to become director of the Norman Bridge Laboratory of Physics at the California Institute of Technology in Pasadena, California. There he undertook a major study of the radiation that the physicist Victor Hess had detected coming from outer space. Millikan proved that this radiation is indeed of extraterrestrial origin, he named it "cosmic rays." As chairman of the Executive Council of Caltech from 1921 until his retirement in 1945, Millikan helped to turn the school into one of the leading research institutions in the United States. He served on the board of trustees for Science Service, now known as Society for Science & the Public, from 1921 to 1953. Robert Andrews Millikan was born on March 1868, in Morrison, Illinois. Millikan went to high school in Iowa. Millikan received a bachelor's degree in the classics from Oberlin College in 1891 and his doctorate in physics from Columbia University in 1895 – he was the first to earn a Ph.
D. from that department. At the close of my sophomore year my Greek professor asked me to teach the course in elementary physics in the preparatory department during the next year. To my reply that I did not know any physics at all, his answer was, "Anyone who can do well in my Greek can teach physics." "All right," said I, "you will have to take the consequences, but I will try and see what I can do with it." I at once purchased an Avery's Elements of Physics, spent the greater part of my summer vacation of 1889 at home – trying to master the subject. I doubt if I have taught better in my life than in my first course in physics in 1889. I was so intensely interested in keeping my knowledge ahead of that of the class that they may have caught some of my own interest and enthusiasm. Millikan's enthusiasm for education continued throughout his career, he was the coauthor of a popular and influential series of introductory textbooks, which were ahead of their time in many ways. Compared to other books of the time, they treated the subject more in the way in which it was thought about by physicists.
They included many homework problems that asked conceptual questions, rather than requiring the student to plug numbers into a formula. Starting in 1908, while a professor at the University of Chicago, Millikan worked on an oil-drop experiment in which he measured the charge on a single electron. J. J. Thomson had discovered the charge-to-mass ratio of the electron. However, the actual charge and mass values were unknown. Therefore, if one of these two values were to be discovered, the other could be calculated. Millikan and his graduate student Harvey Fletcher used the oil-drop experiment to measure the charge of the electron. Professor Millikan took sole credit, in return for Harvey Fletcher claiming full authorship on a related result for his dissertation. Millikan went on to win the 1923 Nobel Prize for Physics, in part for this work, Fletcher kept the agreement a secret until his death. After a publication on his first results in 1910, contradictory observations by Felix Ehrenhaft started a controversy between the two physicists.
After improving his setup, Millikan published his seminal study in 1913. The elementary charge is one of the fundamental physical constants, accurate knowledge of its value is of great importance, his experiment measured the force on tiny charged droplets of oil suspended against gravity between two metal electrodes. Knowing the electric field, the charge on the droplet could be determined. Repeating the experiment for many droplets, Millikan showed that the results could be explained as integer multiples of a common value, the charge of a single electron; that this is somewhat lower than the modern value of 1.602 176 53 x 10−19 coulomb is due to Millikan's use of an inaccurate value for the viscosity of air. Although at the time of Millikan's oil-drop experiments it was becoming clear that there exist such things as subatomic particles, not everyone was convinced. Experimenting with cathode rays in 1897, J. J. Thomson had discovered negatively charged'corpuscles', as he called them, with a charge-to-mass ratio 1840 times that of a hydrogen ion.
Similar results had been found by Walter Kaufmann. Most of what was known about electricity and magnetism, could be explained on the basis that charge is a continuous variable.
Pasadena is a city in Los Angeles County, United States, located 10 miles northeast of Downtown Los Angeles. The estimated population of Pasadena was 142,647 in 2017, making it the 183rd-largest city in the United States. Pasadena is the ninth-largest city in Los Angeles County. Pasadena was incorporated on June 19, 1886, becoming one of the first cities to be incorporated in what is now Los Angeles County, following the city of Los Angeles, it is one of the primary cultural centers of the San Gabriel Valley. The city is known for hosting Tournament of Roses Parade. In addition, Pasadena is home to many scientific and cultural institutions, including Caltech, Pasadena City College, Fuller Theological Seminary, ArtCenter College of Design, the Pasadena Playhouse, the Ambassador Auditorium, the Norton Simon Museum, the USC Pacific Asia Museum; the original inhabitants of Pasadena and surrounding areas were members of the Native American Hahamog-na tribe, a branch of the Tongva Nation. They had lived in the Los Angeles Basin for thousands of years.
Tongva dwellings lined the Arroyo Seco in present day Pasadena and south to where it joins the Los Angeles River and along other natural waterways in the city. The native people lived in dome-shape lodges, they lived on a diet of acorn meal and herbs, other small animals. They traded for ocean fish with the coastal Tongva, they made cooking vessels from steatite soapstone from Catalina Island. The oldest transportation route still in existence in Pasadena is the old Tongva foot trail known as the Gabrielino Trail, that follows the west side of the Rose Bowl and the Arroyo Seco past the Jet Propulsion Laboratory into the San Gabriel Mountains; the trail has been in continuous use for thousands of years. An arm of the trail is still in use in what is now known as Salvia Canyon; when the Spanish occupied the Los Angeles Basin they built the San Gabriel Mission and renamed the local Tongva people "Gabrielino Indians," after the name of the mission. Today, several bands of Tongva people live in the Los Angeles area.
Pasadena is a part of the original Mexican land grant named Rancho del Rincon de San Pascual, so named because it was deeded on Easter Sunday to Eulalia Perez de Guillén Mariné of Mission San Gabriel Arcángel. The Rancho comprised the lands of today's communities of Pasadena and South Pasadena. Before the annexation of California in 1848, the last of the Mexican owners was Manuel Garfias who retained title to the property after statehood in 1850. Garfias sold sections of the property to the first Anglo settlers to come into the area: Dr. Benjamin Eaton, the father of Fred Eaton. Much of the property was purchased by Benjamin Wilson, who established his Lake Vineyard property in the vicinity. Wilson, known as Don Benito to the local Indians owned the Rancho Jurupa and was mayor of Los Angeles, he was the grandfather of Jr. and the namesake of Mount Wilson. In 1873, Wilson was visited by Dr. Daniel M. Berry of Indiana, looking for a place in the country that could offer a mild climate for his patients, most of whom suffered from respiratory ailments.
Berry claimed that he had his best three night's sleep at Rancho San Pascual. To keep the find a secret, Berry code-named the area "Muscat" after the grape. To raise funds to bring the company of people to San Pascual, Berry formed the Southern California Orange and Citrus Growers Association and sold stock in it; the newcomers were able to purchase a large portion of the property along the Arroyo Seco and on January 31, 1874, they incorporated the Indiana Colony. As a gesture of good will, Wilson added 2,000 acres of then-useless highland property, part of which would become Altadena. Colonel Jabez Banbury opened the first school on South Orange Grove Avenue. Banbury had twin daughters, named Jessie; the two became the first students to attended Pasadena’s first school on Orange Grove. At the time, the Indiana Colony was a narrow strip of land between the Arroyo Seco and Fair Oaks Avenue. On the other side of the street was Wilson's Lake Vineyard development. After more than a decade of parallel development on both sides, the two settlements merged into the City of Pasadena.
The popularity of the region drew people from across the country, Pasadena became a stop on the Atchison and Santa Fe Railway, which led to an explosion in growth. From the real estate boom of the 1880s until the Great Depression, as great tourist hotels were developed in the city, Pasadena became a winter resort for wealthy Easterners, spurring the development of new neighborhoods and business districts, increased road and transit connections with Los Angeles, culminating with the opening of the Arroyo Seco Parkway, California's first freeway. By 1940, Pasadena had become the eighth-largest city in California and was considered a twin city to Los Angeles; the first of the great hotels to be established in Pasadena was the Raymond atop Bacon Hill, renamed Raymond Hill after construction. Pasadena was served by the Atchison and Santa Fe Railway at the Santa Fe Depot in downtown when the Second District was opened in 1887; the original Mansard Victorian 200-room facility burned down on Easter morning of 1895, was rebuilt in 1903, razed during the Great Depression to make way for residential development.
The Maryland Hotel existed from the early 1900s and was demolished in 1934. The world-famous Mount Lowe Railway and associated mountain hotels shu
The modern tutu is a dress worn as a costume in a ballet performance with attached bodice. It may be made of tarlatan, silk, gauze, or nylon. Modern tutus have two basic types: the Romantic tutu is soft and bell-shaped, reaching the calf or ankle; the derivation of the word tutu is unknown. The word was not recorded anywhere until 1881. One theory is that it is derived from the word tulle. Another theory is that it derives from French babytalk for bottom: during that era, the abonnés were encouraged to mix with the ballet girls in the foyer, arrange assignations, it is suggested the expression came from the abonnés playfully patting the back of the tulle dress with the saying pan-pan cucul. A third, related theory suggests a derivation from the more vulgar French word, "cul". During this era, women wore pantalettes as underwear; the abonnés favoured the front rows in the hope of a scandalous view, the skirt was modified for that reason. This is supported by the description by nineteenth-century balletomane, Charles Nuitter, who defined tutu as "a slang term for the short petticoat worn by danseuses in the interest of modesty."
The skirt that became known as the Romantic tutu made its first appearance in 1832 at the Paris Opera, where Marie Taglioni wore a gauzy white skirt cut to reveal her ankles, designed by Eugene Lami in La Sylphide. From the late 19th century onwards, the tutu was shortened, for ease of movement and to show off the dancer's legs. Fashion designers have been involved in design for ballet. Fashion designers Cecil Beaton in England, Christian Lacroix in France, Isaac Mizrahi in the United States have all designed tutus. Among the leading makers of tutus around the world, few designers have matched the reputation of Barbara Karinska, Ukrainian costumer for the New York City Ballet for many years, She designed and constructed tutus of extraordinary beauty and durability. "The story of a Swan Lake tutu". Ballet News. June 2, 2010. Dancewear Through the Ages An Inside Look at the Costumes of the New York City Ballet Pictures of tutus Ballet costume
Electrical engineering is a professional engineering discipline that deals with the study and application of electricity and electromagnetism. This field first became an identifiable occupation in the half of the 19th century after commercialization of the electric telegraph, the telephone, electric power distribution and use. Subsequently and recording media made electronics part of daily life; the invention of the transistor, the integrated circuit, brought down the cost of electronics to the point they can be used in any household object. Electrical engineering has now divided into a wide range of fields including electronics, digital computers, computer engineering, power engineering, telecommunications, control systems, radio-frequency engineering, signal processing and microelectronics. Many of these disciplines overlap with other engineering branches, spanning a huge number of specializations such as hardware engineering, power electronics and waves, microwave engineering, electrochemistry, renewable energies, electrical materials science, much more.
See glossary of electrical and electronics engineering. Electrical engineers hold a degree in electrical engineering or electronic engineering. Practising engineers may be members of a professional body; such bodies include the Institute of Electrical and Electronics Engineers and the Institution of Engineering and Technology. Electrical engineers work in a wide range of industries and the skills required are variable; these range from basic circuit theory to the management skills required of a project manager. The tools and equipment that an individual engineer may need are variable, ranging from a simple voltmeter to a top end analyzer to sophisticated design and manufacturing software. Electricity has been a subject of scientific interest since at least the early 17th century. William Gilbert was a prominent early electrical scientist, was the first to draw a clear distinction between magnetism and static electricity, he is credited with establishing the term "electricity". He designed the versorium: a device that detects the presence of statically charged objects.
In 1762 Swedish professor Johan Carl Wilcke invented a device named electrophorus that produced a static electric charge. By 1800 Alessandro Volta had developed the voltaic pile, a forerunner of the electric battery In the 19th century, research into the subject started to intensify. Notable developments in this century include the work of Hans Christian Ørsted who discovered in 1820 that an electric current produces a magnetic field that will deflect a compass needle, of William Sturgeon who, in 1825 invented the electromagnet, of Joseph Henry and Edward Davy who invented the electrical relay in 1835, of Georg Ohm, who in 1827 quantified the relationship between the electric current and potential difference in a conductor, of Michael Faraday, of James Clerk Maxwell, who in 1873 published a unified theory of electricity and magnetism in his treatise Electricity and Magnetism. In 1782 Georges-Louis Le Sage developed and presented in Berlin the world's first form of electric telegraphy, using 24 different wires, one for each letter of the alphabet.
This telegraph connected two rooms. It was an electrostatic telegraph. In 1795, Francisco Salva Campillo proposed an electrostatic telegraph system. Between 1803-1804, he worked on electrical telegraphy and in 1804, he presented his report at the Royal Academy of Natural Sciences and Arts of Barcelona. Salva’s electrolyte telegraph system was innovative though it was influenced by and based upon two new discoveries made in Europe in 1800 – Alessandro Volta’s electric battery for generating an electric current and William Nicholson and Anthony Carlyle’s electrolysis of water. Electrical telegraphy may be considered the first example of electrical engineering. Electrical engineering became a profession in the 19th century. Practitioners had created a global electric telegraph network and the first professional electrical engineering institutions were founded in the UK and USA to support the new discipline. Francis Ronalds created an electric telegraph system in 1816 and documented his vision of how the world could be transformed by electricity.
Over 50 years he joined the new Society of Telegraph Engineers where he was regarded by other members as the first of their cohort. By the end of the 19th century, the world had been forever changed by the rapid communication made possible by the engineering development of land-lines, submarine cables, from about 1890, wireless telegraphy. Practical applications and advances in such fields created an increasing need for standardised units of measure, they led to the international standardization of the units volt, coulomb, ohm and henry. This was achieved at an international conference in Chicago in 1893; the publication of these standards formed the basis of future advances in standardisation in various industries, in many countries, the definitions were recognized in relevant legislation. During these years, the study of electricity was considered to be a subfield of physics since the early electrical technology was considered electromechanical in nature; the Technische Universität Darmstadt founded the world's first department of electrical engineering in 1882.
The first electrical engineering degree program was started at Massachusetts Institute of Technology in the physics department