Neoclassical architecture is an architectural style produced by the neoclassical movement that began in the mid-18th century. In its purest form, it is a style principally derived from the architecture of classical antiquity, the Vitruvian principles, the work of the Italian architect Andrea Palladio. In form, neoclassical architecture emphasizes the wall rather than chiaroscuro and maintains separate identities to each of its parts; the style is manifested both in its details as a reaction against the Rococo style of naturalistic ornament, in its architectural formulae as an outgrowth of some classicising features of the Late Baroque architectural tradition. Neoclassical architecture is still designed today, but may be labelled New Classical Architecture for contemporary buildings. In Central and Eastern Europe, the style is referred to as Classicism, while the newer revival styles of the 19th century until today are called neoclassical. Intellectually, neoclassicism was symptomatic of a desire to return to the perceived "purity" of the arts of Rome, to the more vague perception of Ancient Greek arts and, to a lesser extent, 16th-century Renaissance Classicism, a source for academic Late Baroque architecture.
Many early 19th-century neoclassical architects were influenced by the drawings and projects of Étienne-Louis Boullée and Claude Nicolas Ledoux. The many graphite drawings of Boullée and his students depict spare geometrical architecture that emulates the eternality of the universe. There are Edmund Burke's conception of the sublime. Ledoux addressed the concept of architectural character, maintaining that a building should communicate its function to the viewer: taken such ideas give rise to "architecture parlante". A return to more classical architectural forms as a reaction to the Rococo style can be detected in some European architecture of the earlier 18th century, most vividly represented in the Palladian architecture of Georgian Britain and Ireland; the baroque style had never been to the English taste. Four influential books were published in the first quarter of the 18th century which highlighted the simplicity and purity of classical architecture: Vitruvius Britannicus, Palladio's Four Books of Architecture, De Re Aedificatoria and The Designs of Inigo Jones... with Some Additional Designs.
The most popular was the four-volume Vitruvius Britannicus by Colen Campbell. The book contained architectural prints of famous British buildings, inspired by the great architects from Vitruvius to Palladio. At first the book featured the work of Inigo Jones, but the tomes contained drawings and plans by Campbell and other 18th-century architects. Palladian architecture became well established in 18th-century Britain. At the forefront of the new school of design was the aristocratic "architect earl", Richard Boyle, 3rd Earl of Burlington; this House was a reinterpretation of Palladio's Villa Capra, but purified of 16th century elements and ornament. This severe lack of ornamentation was to be a feature of the Palladianism. In 1734 William Kent and Lord Burlington designed one of England's finest examples of Palladian architecture with Holkham Hall in Norfolk; the main block of this house followed Palladio's dictates quite but Palladio's low detached, wings of farm buildings were elevated in significance.
This classicising vein was detectable, to a lesser degree, in the Late Baroque architecture in Paris, such as in Perrault's east range of the Louvre. This shift was visible in Rome at the redesigned façade for S. Giovanni in Laterano. By the mid 18th century, the movement broadened to incorporate a greater range of Classical influences, including those from Ancient Greece. An early centre of neoclassicism was Italy Naples, where by the 1730s, court architects such as Luigi Vanvitelli and Ferdinando Fuga were recovering classical and Mannierist forms in their Baroque architecture. Following their lead, Giovanni Antonio Medrano began to build the first neoclassical structures in Italy in the 1730s. In the same period, Alessandro Pompei introduced neoclassicism to the Venetian Republic, building one of the first lapidariums in Europe in Verona, in the Doric style. During the same period, neoclassical elements were introduced to Tuscany by architect Jean Nicolas Jadot de Ville-Issey, the court architect of Francis Stephen of Lorraine.
On Jadot's lead, an original neoclassical style was developed by Gaspare Paoletti, transforming Florence into the most important centre of neoclassicism in the peninsula. In the second half of the century, Neoclassicism flourished in Turin and Trieste. In the latter two cities, just as in Tuscany, the sober neoclassical style was linked to the reformism of the ruling Habsburg enlightened monarchs; the Rococo style remained much popular in Italy until the Napoleonic regimes, which brought a new archaeological classicism, embraced as a political statement by young, urban Italians with republican leanings. The shift to neoclassical architecture is conventionally dated to the 1750s, it first gained influence in France. In France, the movement was propelled by a generation of French art students trained in Rome, was influenced by the writings of
The Northrop A-17, a development of the Northrop Gamma 2F model, was a two-seat, single-engine, attack bomber built in 1935 by the Northrop Corporation for the U. S. Army Air Corps; when in British Commonwealth service during World War II, the A-17 was called Nomad. The Northrop Gamma 2F was an attack bomber derivative of the Northrop Gamma transport aircraft, developed in parallel with the Northrop Gamma 2C, designated the YA-13 and XA-16; the Gamma 2F had a revised tail, cockpit canopy and wing flaps compared with the Gamma 2C, was fitted with new semi-retractable landing gear. It was delivered to the United States Army Air Corps for tests on 6 October 1934, after modifications which included fitting with a conventional fixed landing gear, was accepted by the Air Corps. A total of 110 aircraft were ordered as the A-17 in 1935; the resulting A-17 was equipped with perforated flaps, had fixed landing gear with partial fairings. It was fitted with an internal fuselage bomb bay that carried fragmentation bombs and well as external bomb racks.
Northrop developed new landing gear, this time retractable, producing the A-17A variant. This version was again purchased by the Army Air Corps. By the time these were delivered, the Northrop Corporation had been taken over by Douglas Aircraft Company, export models being known as the Douglas Model 8; the A-17 entered service in February 1936, proved a reliable and popular aircraft. However, in 1938, the Air Corps decided that attack aircraft should be multi-engined, rendering the A-17 surplus to requirements. From 14 December 1941, A-17s were used for coastal patrols by the 59th Bombardment Squadron on the Pacific side of the Panama Canal; the last remaining A-17s, used as utility aircraft, were retired from USAAF service in 1944. Argentina purchased 30 Model 8A-2s in 1937 and received them between February and March 1938; these remained in frontline service until replaced by the I. Ae. 24 Calquin, continuing in service as trainers and reconnaissance aircraft until their last flight in 1954. Peru ordered these being delivered from 1938 onwards.
These aircraft were used in combat by Peru in the Ecuadorian-Peruvian war of July 1941. The survivors of these aircraft were supplemented by 13 Model 8A-5s from Norway, delivered via the United States in 1943; these remained in service until 1958. The Swedish government purchased a licence for production of a Mercury-powered version, building 63 B 5Bs and 31 B 5Cs, production taking place from 1938 to 1941, they were replaced in service with the Swedish Air Force by SAAB 17s from 1944. The Swedish version was used as a dive bomber and as such it featured prominently in the 1941 film Första divisionen; the Netherlands, in urgent need of modern combat aircraft, placed an order for 18 Model 8A-3Ns in 1939, with all being delivered by the end of the year. Used in a fighter role for which they were unsuited, the majority were destroyed by Luftwaffe attacks on 10 May 1940, the first day of the German invasion. Iraq purchased 15 Model 8A-4s, in 1940, they were destroyed in the Anglo-Iraqi War in 1941.
Norway ordered 36 Model 8A-5Ns in 1940. These were not ready by the time of the German Invasion of Norway and were diverted to the Norwegian training camp in Canada, which became known as Little Norway. Norway decided to sell 18 of these aircraft as surplus to Peru, but these were embargoed by the United States, who requisitioned the aircraft, using them as trainers, designating them the A-33. Norway sold their surviving aircraft to Peru in 1943. In June 1940, 93 ex-USAAC aircraft were purchased by France, refurbished by Douglas, including being given new engines; these were not delivered before the fall of France and 61 were taken over by the British Purchasing Commission for the British Commonwealth use under the name Northrop Nomad Mk I. After the RAF assessed the Northrop Nomad Mk Is as "obsolete", most of the Nomads were sent to South Africa for use as trainers and target tugs; the Nomads suffered shortages of spare parts and from 1942 were replaced by Fairey Battles. The last Nomads were retired in 1944.
The Royal Canadian Air Force received 32 Nomads, part of a French order of 93 aircraft. When France fell in 1940, this order was taken over by Great Britain who transferred 32 of the aircraft to Canada where they were used as advanced trainers and target tugs as part of the British Commonwealth Air Training Plan; these were serialed 3490 to 3521. A-17 Initial production for USAAC. Fixed gear, powered by 750 hp Pratt & Whitney R-1535-11 Twin Wasp Jr engine. A-17A Revised version for USAAC with retractable gear and 825 hp R-1535-13 engine. A-17AS Three seat staff transport version for USAAC. Powered by 600 hp Pratt & Whitney R-1340 Wasp engine. Model 8A-1 Export version for Sweden. Fixed gear. Two Douglas built prototypes, followed by 63 licensed built B 5B aircraft powered by 920 hp Bristol Mercury XXIV engine. Model 8A-2 Version for Argentina. Fitted with fixed gear, ventral gun position and powered by 840 kW Wright R-1820-G3 Cyclone. Model 8A-3N Version of A-17A for Netherlands. Powered by 1,100 hp Pratt & Whitney R-1830 Twin Wasp S3C-G engine.
Model 8A-3P Version of A-17A for Peru. Powered by 1,000 hp GR-1820-G103 engine. Model 8A-4 Version for Iraq, powered by a 1,000 hp GR-1820-G103 engine. Model 8A-5N Version for Norway, powered by 1,200 hp GR-1830-G205A engine. Impressed int
The Diablo Range is a mountain range in the California Coast Ranges subdivision of the Pacific Coast Ranges. It is located in the eastern San Francisco Bay area south to the Salinas Valley area of northern California, the United States; the Diablo Range extends from the Carquinez Strait in the north to Orchard Peak in the south, near the point where State Route 46 crosses over the Coast Ranges at Cholame, as described by the USGS. It is bordered on the northeast by the San Joaquin River, on the southeast by the San Joaquin Valley, on the southwest by the Salinas River, on the northwest by the Santa Clara Valley; the USGS designation is somewhat ambiguous north of the Santa Clara Valley, but on their maps, the range is shown as the ridgeline which runs between its namesake Mount Diablo southeastward past Mount Hamilton. Geologically, the range corresponds to the California Coast Ranges east of the Calaveras Fault in this northern section. For much of the length of the Diablo Range, it is paralleled by other sections of the California Coast Ranges to the west, the Santa Cruz Mountains across the southern San Francisco Bay and Santa Clara Valley, the Santa Lucia Range across the Salinas Valley.
The range passes through Contra Costa, San Joaquin, Santa Clara, Merced, San Benito, Fresno and Kings Counties, ends in the northwesternmost extremity of Kern County. Though the average elevation is about 3,000 feet, a summit at over 2,300 feet is considered high because the range is rolling grasslands and plateaus, punctuated by sudden peaks; the plateaus are at about 2,000–3,000 feet. The hills rising out of valleys rise to about 1,000 feet at most, the hills rolling around inland plateaus go from 1,500–2,500 feet. Foothills, such as the which are found near the Santa Clara Valley, Livermore Valley and San Joaquin Valley, are lowest, from 400–1,000 feet. Canyons are 300–400 feet deep and valleys are deeper but gentler; the peaks have high topographic prominence because they are surrounded by hills, valleys, or lower plateaus. Streams draining the eastern slopes of the Diablo Range include Ingram Creek. Stream draining the western slopes include Coyote Creek; the Diablo Range's following peaks and ridges are between 2,517–5,241 feet and are distinct landmarks.
Mount Diablo, San Benito Mountain, Mount Hamilton Ridge, Mount Stakes. The Diablo Range is paralleled for much of its distance by U. S. Route 101 by I-5 to the east. Major routes of travel through the range include: North of the range BNSF Railway/Amtrak San Joaquin Willow Pass State Route 4 Antioch–SFO/Millbrae BART Altamont Pass Union Pacific Railroad/Altamont Corridor Express I-580 Sunol Valley State Route 84 I-680 Pacheco Pass State Route 152 Future California High-Speed Rail State Route 198 Cottonwood Pass Polonio Pass A sparsely used gravel road is the highest road in the range, with its highest point being on San Benito Mountain at over 5,000 feet; the Diablo Range is unpopulated outside of the San Francisco Bay Area. Major nearby communities include Antioch, Walnut Creek, San Ramon, Livermore, Milpitas, San Jose, Morgan Hill, Gilroy. and the Central Valley city of Tracy. South of Pacheco Pass, the only major nearby communities are Los Banos, Hollister; the small town of Coalinga may be notable for its location on State Route 198, one of the few routes through the mountains.
Most of the range consists of private ranchland. However, the range does contain several areas of parkland, including Mount Diablo State Park, Alum Rock Park, Grant Ranch Park, Henry W. Coe State Park, Laguna Mountain Recreation Area, the BLM's Clear Creek Management Area. In addition, some private land is held in conservation easements by the California Rangeland Trust. Since the range lies around 10 to 50 miles inland from the ocean, other coastal ranges like the Santa Lucia Range and the Santa Cruz Mountains block incoming moisture, the range gets little precipitation. In addition, the average elevation of 3,000 feet is not high enough to catch most of the incoming moisture at higher altitudes. Winters are mild with moderate rainfall, but summers are dry and hot. Areas above 2,500 feet get light to moderate snow in the winter at the highest point, the 5,241 ft San Benito Mountain in the remote southeastern section of the range. However, though sites at the lower end get annual snowfall, it is light and melts too fast to be noticed.
Once or twice a decade there is deep and long lasting snowfall. Mercury contamination near the southern end of the range is an ongoing problem, due to the New Idria quicksilver mines, which stopped production in the 1970s. Heavy mercury contamination has been documented in the San Carlos and Silver Creeks, which flow into Panoche Creek, thence into the San Joaquin River; this has resulted in mercury contamination all the way downstream to the San Francisco Bay. Silver and San Carlos creeks provide a wetland environment in an otherwise arid region and are important for the ecology of the region; as of 2011, New Idria has been scheduled for cleanup. The Diablo Range is part of the California interior chaparral and woodlands ecoregion, it is covered by chaparral and California oak woodland communities, with stands of closed-cone pine forests appearing above 4,000 feet. The native bunch grass savanna has be
A refracting telescope is a type of optical telescope that uses a lens as its objective to form an image. The refracting telescope design was used in spy glasses and astronomical telescopes but is used for long focus camera lenses. Although large refracting telescopes were popular in the second half of the 19th century, for most research purposes the refracting telescope has been superseded by the reflecting telescope which allows larger apertures. A refractor's magnification is calculated by dividing the focal length of the objective lens by that of the eyepiece. Refractors were the earliest type of optical telescope; the first practical refracting telescopes appeared in the Netherlands about 1608, were credited to three individuals, Hans Lippershey and Zacharias Janssen, spectacle-makers in Middelburg, Jacob Metius of Alkmaar. Galileo Galilei, happening to be in Venice in about the month of May 1609, heard of the invention and constructed a version of his own. Galileo communicated the details of his invention to the public, presented the instrument itself to the Doge Leonardo Donato, sitting in full council.
All refracting telescopes use the same principles. The combination of an objective lens 1 and some type of eyepiece 2 is used to gather more light than the human eye is able to collect on its own, focus it 5, present the viewer with a brighter and magnified virtual image 6; the objective in a refracting telescope bends light. This refraction causes parallel light rays to converge at a focal point; the telescope converts a bundle of parallel rays to make an angle α, with the optical axis to a second parallel bundle with angle β. The ratio β/α is called the angular magnification, it equals the ratio between the retinal image sizes obtained without the telescope. Refracting telescopes can come in many different configurations to correct for image orientation and types of aberration; because the image was formed by the bending of light, or refraction, these telescopes are called refracting telescopes or refractors. The design Galileo Galilei used in 1609 is called a Galilean telescope, it used a divergent eyepiece lens.
A Galilean telescope, because the design has no intermediary focus, results in a non-inverted and upright image. Galileo's best telescope magnified objects about 30 times; because of flaws in its design, such as the shape of the lens and the narrow field of view, the images were blurry and distorted. Despite these flaws, the telescope was still good enough for Galileo to explore the sky; the Galilean telescope could view the phases of Venus, was able to see craters on the Moon and four moons orbiting Jupiter. Parallel rays of light from a distant object would be brought to a focus in the focal plane of the objective lens; the eyepiece lens renders them parallel once more. Non-parallel rays of light from the object traveling at an angle α1 to the optical axis travel at a larger angle after they passed through the eyepiece; this leads to an increase in the apparent angular size and is responsible for the perceived magnification. The final image is a virtual image, is the same way up as the object.
The Keplerian telescope, invented by Johannes Kepler in 1611, is an improvement on Galileo's design. It uses a convex lens as the eyepiece instead of Galileo's concave one; the advantage of this arrangement is that the rays of light emerging from the eyepiece are converging. This allows for a much wider field of view and greater eye relief, but the image for the viewer is inverted. Higher magnifications can be reached with this design, but to overcome aberrations the simple objective lens needs to have a high f-ratio; the design allows for use of a micrometer at the focal plane. The achromatic refracting lens was invented in 1733 by an English barrister named Chester Moore Hall, although it was independently invented and patented by John Dollond around 1758; the design overcame the need for long focal lengths in refracting telescopes by using an objective made of two pieces of glass with different dispersion,'crown' and'flint glass', to limit the effects of chromatic and spherical aberration.
Each side of each piece is ground and polished, the two pieces are assembled together. Achromatic lenses are corrected to bring two wavelengths into focus in the same plane; the era of the'great refractors' in the 19th century saw large achromatic lenses culminating with the largest achromatic refractor built, the Great Paris Exhibition Telescope of 1900. Apochromatic refractors have objectives built with extra-low dispersion materials, they are designed to bring three wavelengths into focus in the same plane. The residual color error can be up than that of an achromatic lens; such telescopes contain elements of fluorite or special, extra-low dispersion glass in the objective and produce a crisp image, free of chromatic aberration. Due to the special materials needed in the fabrication, apochromatic refractors are more expensive than telescopes of other types with a comparable aperture. Refractors suffer from residual spherical aberration; this affects shorter focal ratios more than longer ones.
James Lick was an American real estate investor, piano builder, land baron, patron of the sciences. At the time of his death, he was the wealthiest man in California, left the majority of his estate to social and scientific causes. James Lick was born in Stumpstown Pennsylvania on August 25, 1796. Lick's grandfather, William Lick, served during the American Revolutionary War under General George Washington and his son, John Lick, during the American Civil War; the son of a carpenter, Lick began learning the craft at an early age. When he was twenty-one, after a failed romance with Barbara Snavely, Lick left Stumpstown for Baltimore, where he learned the art of piano making, he mastered the skill, moved to New York City and set up his own shop. In 1821 Lick moved to Argentina, after learning that his pianos were being exported to South America. Lick found his time in Buenos Aires to be difficult, due to his ignorance of Spanish and the turbulent political situation in the country. However, his business in 1825 Lick left Argentina to tour Europe for a year.
On his return trip, his ship was captured by the Portuguese, the passengers and crew were taken to Montevideo as prisoners of war. Lick returned to Buenos Aires on foot. In 1832, Lick decided to return to Stumpstown, he returned to Buenos Aires. He moved to Valparaíso, Chile. After four years, he again moved this time to Lima, Peru. In 1846, Lick decided to return to North America and, anticipating the Mexican–American War and the future annexation of California, he decided to settle there. However, a backlog of orders for his pianos delayed him an additional 18 months, as the Mexican workers he employed left to return to their homes and join the Mexican Army following the outbreak of war in April of that year, he finished the orders himself. Lick arrived in San Francisco, California, in January 1848, bringing with him his tools, work bench, $30,000 in gold, 600 pounds of chocolate; the chocolate sold. So, Lick sent back word convincing his friend and neighbor in Peru, the confectioner Domingo Ghirardelli, to move to San Francisco, where he founded the Ghirardelli Chocolate Company.
Upon his arrival, Lick began buying real estate in the small village of San Francisco. The discovery of gold at Sutter's Mill near Sacramento a few days after Lick's arrival in the future state began the California Gold Rush and created a housing boom in San Francisco, which grew from about one thousand residents in 1848 to over twenty thousand by 1850. Lick himself got a touch of "gold fever" and went out to mine the metal, but after a week he decided his fortune was to be made by owning land, not digging in it. Lick continued buying land in San Francisco, began buying farmland in and around San Jose, where he planted orchards and built the largest flour mill in the state to feed the growing population in San Francisco. In 1861, Lick began construction of a hotel, which became known as Lick House, at the intersection of Montgomery and Sutter Streets in San Francisco; the hotel had a dining room that could seat 400, based on a similar room at the palace of Versailles. Lick House was considered the finest hotel west of the Mississippi River.
The hotel was destroyed in the fire following the San Francisco earthquake of 1906. Following the construction, Lick returned to his San Jose orchards. In 1874, Lick suffered a massive stroke in the kitchen of his home in Santa Clara; the following morning, he was found by his employee, Thomas Fraser, taken to Lick House, where he could be better cared for. At the time of his illness, his estates, outside his considerable area in Santa Clara County and San Francisco, included large holdings around Lake Tahoe, a large ranch in Los Angeles County, all of Santa Catalina Island, making Lick the richest man in California. In the next three years, Lick spent his time determining, he wanted to build giant statues of himself and his parents, erect a pyramid larger than the Great Pyramid of Giza in his own honor in downtown San Francisco. However, through the efforts of George Davidson, president of the California Academy of Sciences, Lick was persuaded to leave the greatest portion of his fortune to the establishment of a mountaintop observatory, with the largest, most powerful telescope yet built by man.
In 1874 he placed $3,000,000 at the disposal of seven trustees, by whom the funds were to be applied to specific uses. The principal divisions of the funds were: $700,000 to the University of California for the construction of an observatory and the placing therein of a telescope to be more powerful than any other in existence $150,000 for the building and maintenance of free public James Lick Baths in San Francisco $540,000 to found and endow an institution of San Francisco to be known as the California School of Mechanic Arts $100,000 for the erection of three appropriate groups of bronze statuary to represent three periods in Californian history and to be placed before the city hall of San Francisco $60,000 to erect in Golden Gate Park, San Francisco, a memorial to Francis Scott Key, author of “The Star-Spangled Banner”Lick had had an interest in astronomy since at least 1860, when he and George Madeira, the founder of the first observatory in California, spent several nights observing.
They had met again in 1873 and Lick said that Madeira's telescopes were the only ones he had used. In 1875, Thomas Fraser recommended a site near San Jose. Lick approved, on
Edward Emerson Barnard
Edward Emerson Barnard was an American astronomer. He was known as E. E. Barnard, was recognized as a gifted observational astronomer, he is best known for his discovery of the high proper motion of Barnard's Star in 1916, named in his honor. Barnard was born in Nashville, Tennessee, to Reuben Barnard and Elizabeth Jane Barnard, had one brother, his father died three months before his birth, so he grew up in an impoverished family and did not receive much in the way of formal education. His first interest was in the field of photography, he became a photographer's assistant at the age of nine, he developed an interest in astronomy. In 1876 he purchased a 5-inch refractor telescope, in 1881 he discovered his first comet, but failed to announce his discovery, he found his second comet the same year and a third in 1882. While he was still working at a photography studio he was married to the English-born woman Rhoda Calvert in 1881. In the 1880s, Hulbert Harrington Warner offered US$200 per discovery of a new comet.
Barnard discovered a total of five, used the money to build a house for himself and his wife. With his name being brought to the attention of amateur astronomers in Nashville, they collectively raised enough money to give Barnard a fellowship to Vanderbilt University, he never graduated from the school, but did receive the only honorary degree Vanderbilt has awarded. He joined the staff of the Lick Observatory in 1887, though he clashed with the director, Edward S. Holden, over access to observing time on the larger instruments and other issues of research and management. Barnard saw the gegenschein in 1882, not aware of earlier papers by Theodor Brorsen and T. W. Backhouse. In 1889 he observed; as he watched Iapetus pass through the space between Saturn's innermost rings and the planet itself, he saw a shadow pass over the moon. Although he did not realize it at the time, he had discovered proof of the "spokes" of Saturn, dark shadows running perpendicular to the circular paths of the rings.
These spokes were doubted at first, but confirmed by the spacecraft Voyager 1. In 1892 he made observations of a nova and was the first to notice the gaseous emissions, thus deducing that it was a stellar explosion; the same year he discovered Amalthea, the fifth moon of Jupiter. He was the first to discover a new moon of Jupiter since Galileo Galilei in 1609; this was the last satellite discovered by visual observation. In 1895 he joined the University of Chicago as professor of astronomy. There he was able to use the 40-inch telescope at Yerkes Observatory. Much of his work during this period was taking photographs of the Milky Way. Together with Max Wolf, he discovered that certain dark regions of the galaxy were clouds of gas and dust that obscured the more distant stars in the background. From 1905, his niece Mary R. Calvert worked as his computer; the faint Barnard's Star is named for Edward Barnard after he discovered in 1916 that it had a large proper motion, relative to other stars. This is the second nearest star system to the Sun, second only to the Alpha Centauri system.
He was a pioneering astrophotographer. His Barnard Catalogue lists a series of dark nebulae, known as Barnard objects, giving them numerical designations akin to the Messier catalog, they begin with Barnard 1 and end with Barnard 370. He published his initial list with the 1919 paper in the Astrophysical Journal, "On the Dark Markings of the Sky with a Catalogue of 182 such Objects", he died on February 6, 1923 in Williams Bay and was buried in Nashville. After his death, many examples from his exceptional collection of astronomical photographs were published in 1927 as A Photographic Atlas of Selected Regions of the Milky Way, this work having been finished by Edwin B. Frost director of Yerkes Observatory, Mary R. Calvert. Between 1881 and 1892, he discovered 15 comets, three of which were periodic, co-discovered two others: C/1881 did not announce C/1881 S1 C/1882 R2 D/1884 O1 C/1885 N1 C/1885 X2 C/1886 T1 Barnard-Hartwig C/1887 B3 C/1887 D1 C/1887 J1 C/1888 U1 C/1888 R1 C/1889 G1 177P/Barnard C/1891 F1 Barnard-Denning C/1891 T1 D/1892 T1 – First comet to be discovered by photography.
The Immortal Fire Within: The Life and Work of Edward Emerson Barnard. Cambridge: Cambridge University Press. Biography Edward Emerson Barnard's Photographic Atlas of Selected Regions of the Milky Way National Academy of Sciences Biographical Memoir Portraits of Edward Emerson Barnard from the Lick Observatory Records Digital Archive, UC Santa Cruz Library's Digital Collections
Telegraphy is the long-distance transmission of textual or symbolic messages without the physical exchange of an object bearing the message. Thus semaphore is a method of telegraphy. Telegraphy requires that the method used for encoding the message be known to both sender and receiver. Many methods are designed according to the limits of the signalling medium used; the use of smoke signals, reflected light signals, flag semaphore signals are early examples. In the 19th century, the harnessing of electricity led to the invention of electrical telegraphy; the advent of radio in the early 20th century brought about radiotelegraphy and other forms of wireless telegraphy. In the Internet age, telegraphic means developed in sophistication and ease of use, with natural language interfaces that hide the underlying code, allowing such technologies as electronic mail and instant messaging; the word "telegraph" was first coined by the French inventor of the Semaphore telegraph, Claude Chappe, who coined the word "semaphore".
A "telegraph" is a device for transmitting and receiving messages over long distances, i.e. for telegraphy. The word "telegraph" alone now refers to an electrical telegraph. Wireless telegraphy, transmission of messages over radio with telegraphic codes. Contrary to the extensive definition used by Chappe, Morse argued that the term telegraph can be applied only to systems that transmit and record messages at a distance; this is to be distinguished from semaphore, which transmits messages. Smoke signals, for instance, are to be considered semaphore, not telegraph. According to Morse, telegraph dates only from 1832 when Pavel Schilling invented one of the earliest electrical telegraphs. A telegraph message sent by an electrical telegraph operator or telegrapher using Morse code was known as a telegram. A cablegram was a message sent by a submarine telegraph cable shortened to a cable or a wire. A Telex was a message sent by a Telex network, a switched network of teleprinters similar to a telephone network.
A wire picture or wire photo was a newspaper picture, sent from a remote location by a facsimile telegraph. A diplomatic telegram known as a diplomatic cable, is the term given to a confidential communication between a diplomatic mission and the foreign ministry of its parent country; these continue to be called cables regardless of the method used for transmission. Passing messages by signalling over distance is an ancient practice. One of the oldest examples is the signal towers of the Great Wall of China. In 400 BC, signals could drum beats. By 200 BC complex flag signalling had developed, by the Han dynasty signallers had a choice of lights, flags, or gunshots to send signals. By the Tang dynasty a message could be sent 700 miles in 24 hours; the Ming dynasty added artillery to the possible signals. While the signalling was complex, only predetermined messages could be sent; the Chinese signalling system extended well beyond the Great Wall. Signal towers away from the wall were used to give early warning of an attack.
Others were built further out as part of the protection of trade routes the Silk Road. Signal fires were used in Europe and elsewhere for military purposes; the Roman army made frequent use of them, as did their enemies, the remains of some of the stations still exist. Few details have been recorded of European/Mediterranean signalling systems and the possible messages. One of the few for which details are known is a system invented by Aeneas Tacticus. Tacitus's system had water filled pots at the two signal stations which were drained in synchronisation. Annotation on a floating scale indicated which message was being received. Signals sent by means of torches indicated when to start and stop draining to keep the synchronisation. None of the signalling systems discussed above are true telegraphs in the sense of a system that can transmit arbitrary messages over arbitrary distances. Lines of signalling relay stations can send messages to any required distance, but all these systems are limited to one extent or another in the range of messages that they can send.
A system like flag semaphore, with an alphabetic code, can send any given message, but the system is designed for short-range communication between two persons. An engine order telegraph, used to send instructions from the bridge of a ship to the engine room, fails to meet both criteria. There was only one ancient signalling system described; that was a system using the Polybius square to encode an alphabet. Polybius suggested using two successive groups of torches to identify the coordinates of the letter of the alphabet being transmitted; the number of said torches held up signalled the grid square. The system would have been slow for military purposes and there is no record of it being used. An optical telegraph, or semaphore telegraph is a telegraph consisting of a line of stations in towers or natural high points which signal to each other by means of shutters or paddles. Early proposals for an optical telegraph system were made to the Royal Society by Robert Hooke in 1684 and were first implemented on an experimental level by Sir Richard Lovell Edgeworth in 1767.
The first successful optical telegraph network was invented by Claude Chappe and operated in France from 1