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+---
+title: "History of agricultural science"
+chunk: 1/1
+source: "https://en.wikipedia.org/wiki/History_of_agricultural_science"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:13.737821+00:00"
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+---
+
+The history of agricultural science is a sub-field of the history of agriculture which looks at the scientific advancement of techniques and understanding of agriculture. Early study of organic production in botanical gardens was continued in with agricultural experiment stations in several countries.
+Fertilizer is a major contribution to agriculture history increasing the fertility of the soil and minimizing nutrient loss. Scientific study of fertilizer was advanced significantly in 1840 with the publication Die organische Chemie in ihrer Anwendung auf Agrikulturchemie und Physiologie (Organic Chemistry in Its Applications to Agriculture and Physiology) by Justus von Liebig. One of Liebig's advances in agricultural science was the discovery of nitrogen as an essential plant nutrient.
+
+
+== Fertilizer ==
+
+The first method of soil nourishment utilized compost. Composting used rotten organic materials to replenish the soil of its nutrients and dates back to tenth and twelfth century Arab writings. Composting was a normal and widely used practice of fertilization, up into the twentieth century.
+Johann Friedrich Mayer was the first scientist to publish experiments on the use of gypsum as a fertilizer, but the mechanism that made it function as a fertilizer was contested by his contemporaries.
+Agricultural science developed when analytical chemistry began to address organic compounds. Fertilization with decomposed plants sometimes gave a whiff of ammonia, which suggested a role for nitrogen in biological growth. Gerardus Mulder tried to determine the chemical formula for albumin and similar biological substances, but Justus von Liebig is usually cited as the early visionary of protein structure. For instance, he assigned his student Eben Horsford  the task of comparing the nitrogen content of grains. More significantly, Liebig analysed biological growth as constrained by limiting factors such as a shortage of phosphorus, potassium or nitrogen. His view is called Liebig's law of the minimum. As the nineteenth century progressed so did soil science and its promulgation by farm journals such as those published by Luther Tucker.
+The production of synthetic ammonia was acquired by Fritz Haber and Carl Bosh. Haber discovered the reaction process to produce ammonia and Bosh was able to pressurize it to complete the process. Together Haber and Bosch came up with the Haber-Bosch process that fixated nitrogen to produce ammonia that is used in most fertilizers. In 1918 Fritz Haber received a Nobel Prize in Chemistry for the invention of this process. Carl Bosch also received a Nobel Prize in 1918, but for high-pressure studies. Without the pressure studies this process wouldn't be possible.
+In the United States, a scientific revolution in agriculture began with the Hatch Act of 1887, which used the term "agricultural science". The Hatch Act was driven by farmers' interest in knowing the constituents of early artificial fertilizer. Later on, the Smith–Hughes Act of 1917 shifted agricultural education back to its vocational roots, but the scientific foundation had been built. After 1906, public expenditures on agricultural research in the US exceeded private expenditures for the next 44 years.
+
+
+== Genetics ==
+
+A genetic study of agricultural science began with Gregor Mendel's work. Using statistical methods, Mendel developed the model of Mendelian inheritance which accurately describes the inheritance of dominant and recessive genes. His results were controversial at the time and were not widely accepted.
+In 1900, Hugo de Vries published his findings after rediscovering Mendel's work, and in 1905 William Bateson coined the term "genetics" in a letter to Adam Sedgwick. The study of genetics carried into an experiment isolating DNA.
+
+
+== Agronomy ==
+
+In 1843, John Lawes and Joseph Henry Gilbert began a set of long-term field experiments in agronomy at Rothamsted Research Station in England; some of them are still running.
+In 1905, Sir Albert Howard, studied agronomy and focused on organic agriculture processes. In 1943, Howard published his book on An Agriculture Testament.
+
+
+== Education ==
+In 1917 the Smith–Hughes Act allowed agricultural education to enter public schools in the United States.
+Agriculture took a big hit between the late 1920s and early 1930s during the great depression and dust bowl. The Future Farmers of America (FFA), once known as Future Farmers of Virginia, was created to educate and maintain interest of potential farmers in 1926. Over the years this organization, joined with New Farmers of America, changed the world and educated many about farming processes and encouraged agriculture participation.
+National Association of Agricultural Educators (NAAE) began to help give teachers the ability to start a FFA chapter in their school system and standardize the curriculum all over the country.
+There are various universities around the United States which are well known for educating students in the field of the agricultural sciences. These universities include Texas A&M, Stephen F. Austin State University, University of Idaho and many others.
+
+
+== See also ==
+History of agriculture
+List of agricultural scientists
+
+
+== References ==
+
+
+== External links ==

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+title: "History of astronomy"
+chunk: 1/11
+source: "https://en.wikipedia.org/wiki/History_of_astronomy"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:16.412764+00:00"
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+---
+
+The history of astronomy focuses on the efforts of civilizations to understand the universe beyond earth's atmosphere. Astronomy is one of the oldest natural sciences, achieving a high level of success in the second half of the first millennium. Astronomy has origins in the religious, mythological, cosmological, calendrical, and astrological beliefs and practices of prehistory. Early astronomical records date back to the Babylonians around 1000 BC. There is also astronomical evidence of interest from early Chinese, Central American and North European cultures.
+Astronomy was used by early cultures for timekeeping, navigation, spiritual and religious practices, and agricultural planning. Ancient astronomers observed and charted the skies in an effort to learn about the workings of the universe. During the Renaissance Period, revolutionary ideas emerged about astronomy. One such idea was contributed in 1543 by Polish astronomer Nicolaus Copernicus, who developed a heliocentric model that depicted the planets orbiting the Sun. This was the start of the Copernican Revolution, with the invention of the telescope in 1608 playing a key part. Later developments included the reflecting telescope, astronomical photography, astronomical spectroscopy, radio telescopes, cosmic ray astronomy, infrared telescopes, space telescopes, ultraviolet astronomy, X-ray astronomy, gamma-ray astronomy, space probes, neutrino astronomy, and gravitational-wave astronomy.
+The success of astronomy, compared to other sciences, was achieved for several reasons. Astronomy was the first science to have a mathematical foundation. Standardized measuring instruments such as armillary spheres and quadrants provided a solid base for collecting, verifying and communicating data. Throughout the years, astronomy has broadened into multiple subfields such as astrometry, planetary astronomy, astrophysics, astrochemistry astrobiology, stellar astronomy,  galactic astronomy, extragalactic astronomy, and physical cosmology
+
+== Prehistory ==
+
+A 32,500-year-old carved ivory mammoth tusk could contain the oldest known star chart (resembling the constellation Orion). It has also been suggested that drawings on the wall of the Lascaux caves in France dating from 33,000 to 10,000 years ago could be a graphical representation of the Pleiades, the Summer Triangle, and the Northern Crown. Ancient structures with possibly astronomical alignments (such as Stonehenge) probably fulfilled astronomical, religious, and social functions.
+Ancient astronomical artifacts have been found throughout Europe. The artifacts demonstrate that Neolithic and Bronze Age Europeans had a sophisticated knowledge of mathematics and astronomy.
+Among the discoveries are:
+
+Paleolithic archaeologist Alexander Marshack put forward a theory in 1972 that bone sticks from locations like Africa and Europe from possibly as long ago as 35,000 BC could be marked in ways that tracked the Moon's phases, an interpretation that has met with criticism.
+The Warren Field calendar in the Dee River valley of Scotland's Aberdeenshire was first excavated in 2004 but was revealed in 2013 as a find of huge significance. It is to date the oldest known calendar, created around 8,000 BC and predating all other calendars by some 5,000 years. The calendar takes the form of an early Mesolithic monument containing a series of 12 pits which appear to help the observer track lunar months by mimicking the phases of the Moon. It also aligns to sunrise at the winter solstice, thus coordinating the solar year with the lunar cycles. The monument had been maintained and periodically reshaped, perhaps up to hundreds of times, in response to shifting solar/lunar cycles, over the course of 6,000 years, until the calendar fell out of use around 4,000 years ago.
+Goseck circle is located in Germany and belongs to the linear pottery culture. First discovered in 1991, its significance was only clear after results from archaeological digs became available in 2004. The site is one of hundreds of similar circular enclosures built in a region encompassing Austria, Germany, and the Czech Republic during a 200-year period starting shortly after 5000 BC.

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+title: "History of astronomy"
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+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:16.412764+00:00"
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+---
+
+The Nebra sky disc is a Bronze Age bronze disc that was buried on Mittenberg hill in Germany around 1600 BC. It measures about 30 cm (12 in) diameter with a mass of 2.2 kg (4.9 lb) and displays a blue-green patina (from oxidization) inlaid with gold symbols. Found by archeological thieves in 1999 and recovered in Switzerland in 2002, it was soon recognized as a spectacular discovery, among the most important of the 20th century. Investigations revealed that the object had been in use around 400 years before burial (2000 BC), but that its use had been forgotten by the time of burial. The inlaid gold depicted the full moon, a crescent moon about 4 or 5 days old, and the Pleiades star cluster in a specific arrangement, forming the earliest known depiction of celestial phenomena. Twelve lunar months pass in 354 days, requiring a calendar to insert a leap month every two or three years in order to keep synchronized with the solar year's seasons (making it lunisolar). The earliest known descriptions of this coordination were recorded by the Babylonians in the sixth or seventh centuries BC, over one thousand years later. Those descriptions verified ancient knowledge of the Nebra sky disc's celestial depiction as the precise arrangement needed to judge when to insert the intercalary month into a lunisolar calendar, making it an astronomical clock for regulating such a calendar a thousand or more years before any other known method.
+The Kokino site, discovered in 2001, sits atop an extinct volcanic cone at an elevation of 1,013 metres (3,323 ft), occupying about 0.5 hectares overlooking the surrounding countryside in North Macedonia. A Bronze Age astronomical observatory was constructed there around 1900 BC and continuously served the nearby community that lived there until about 700 BC. The central space was used to observe the rising of the Sun and full moon. Three markings locate sunrise at the summer and winter solstices and at the two equinoxes. Four more give the minimum and maximum declinations of the full moon: in summer, and in winter. Two measure the lengths of lunar months. Together, they reconcile solar and lunar cycles in marking the 235 lunations that occur during 19 solar years, regulating a lunar calendar. On a platform separate from the central space, at lower elevation, four stone seats (thrones) were made in north–south alignment, together with a trench marker cut in the eastern wall. This marker allows the rising Sun's light to fall on only the second throne, at midsummer (about July 31). It was used for ritual ceremony linking the ruler to the local sun god, and also marked the end of the growing season and time for harvest.
+
+Golden hats of Germany, France and Switzerland dating from 1400 to 800 BC are associated with the Bronze Age Urnfield culture. The Golden hats are decorated with a spiral motif of the Sun and the Moon. They were probably a kind of calendar used to calibrate between the lunar and solar calendars. Modern scholarship has demonstrated that the ornamentation of the gold leaf cones of the Schifferstadt type, to which the Berlin Gold Hat example belongs, represent systematic sequences in terms of number and types of ornaments per band.  A detailed study of the Berlin example, which is the only fully preserved one, showed that the symbols probably represent a lunisolar calendar. The object would have permitted the determination of dates or periods in both lunar and solar calendars.
+
+== Ancient times ==
+
+Early cultures identified celestial objects with gods and spirits. They related these objects (and their movements) to phenomena such as rain, drought, seasons, and tides. It is generally believed that the first astronomers were priests who believed celestial objects and events to be manifestations of the divine, hence the connection to what is now called astrology. 
+Calendars of the world have often been set by observations of the Sun and Moon (marking the day, month, and year) and were important to agricultural societies, in which the harvest depended on planting at the correct time of year. The nearly full moon was also the only lighting for night-time travel into city markets.
+The common modern calendar is based on the Roman calendar. Although originally a lunar calendar, it broke the traditional link of the month to the phases of the Moon and divided the year into twelve almost-equal months, that mostly alternated between thirty and thirty-one days. Julius Caesar instigated calendar reform in 46 BC and introduced what is now called the Julian calendar, based upon the 365+1⁄4 day year length originally proposed by the 4th century BC Greek astronomer Callippus.
+
+=== Mesopotamia ===

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+title: "History of astronomy"
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+
+With the accumulation of large sets of astronomical data, teams like the Harvard Computers rose in prominence which led to many female astronomers, previously relegated as assistants to male astronomers, gaining recognition in the field. The United States Naval Observatory (USNO) and other astronomy research institutions hired human "computers",  who performed the tedious calculations while scientists performed research requiring more background knowledge. A number of discoveries in this period were originally noted by the women "computers" and reported to their supervisors. Henrietta Swan Leavitt discovered the cepheid variable star period-luminosity relation which she further developed into a method of measuring distance outside of the Solar System.
+A veteran of the Harvard Computers, Annie J. Cannon developed the modern version of the stellar classification scheme in during the early 1900s (O B A F G K M, based on color and temperature), manually classifying more stars in a lifetime than anyone else (around 350,000).
+The twentieth century saw increasingly rapid advances in the scientific study of stars.
+Karl Schwarzschild discovered that the color of a star and, hence, its temperature, could be determined by comparing the visual magnitude against the photographic magnitude. The development of the photoelectric photometer allowed precise measurements of magnitude at multiple wavelength intervals. In 1921 Albert A. Michelson made the first measurements of a stellar diameter using an interferometer on the Hooker telescope at Mount Wilson Observatory.
+
+Important theoretical work on the physical structure of stars occurred during the first decades of the twentieth century. In 1913, the Hertzsprung–Russell diagram was developed, propelling the astrophysical study of stars.
+In Potsdam in 1906, the Danish astronomer Ejnar Hertzsprung published the first plots of color versus luminosity for these stars. These plots showed a prominent and continuous sequence of stars, which he named the Main Sequence.
+At Princeton University, Henry Norris Russell plotted the spectral types of these stars against their absolute magnitude, and found that dwarf stars followed a distinct relationship. This allowed the real brightness of a dwarf star to be predicted with reasonable accuracy.
+Successful models were developed to explain the interiors of stars and stellar evolution. Cecilia Payne-Gaposchkin first proposed that stars were made primarily of hydrogen and helium in her 1925 doctoral thesis. The spectra of stars were further understood through advances in quantum physics. This allowed the chemical composition of the stellar atmosphere to be determined.
+As evolutionary models of stars were developed during the 1930s, Bengt Strömgren introduced the term Hertzsprung–Russell diagram to denote a luminosity-spectral class diagram.
+A refined scheme for stellar classification was published in 1943 by William Wilson Morgan and Philip Childs Keenan.
+
+The existence of the Milky Way, Earth's home galaxy, as a separate group of stars was only proven in the 20th century, as was the knowledge that other galaxies exist and that most of them are moving away from each other. The "Great Debate" between Harlow Shapley and Heber Curtis, in the 1920s, concerned the nature of the Milky Way, spiral nebulae, and the dimensions of the universe.
+With the advent of quantum physics, spectroscopy was further refined.
+The Sun was found to be part of a galaxy made up of more than 1010 stars (10 billion stars). The existence of other galaxies, one of the matters of the great debate, was settled by Edwin Hubble, who identified the Andromeda Nebula as a different galaxy, and many others at large distances and receding, moving away from our galaxy.
+Physical cosmology, a discipline that has a large intersection with astronomy, made huge advances during the 20th century, with the model of the hot Big Bang heavily supported by the evidence provided by astronomy and physics, such as the redshifts of very distant galaxies and radio sources, the cosmic microwave background radiation, Hubble's law and cosmological abundances of elements.
+
+== See also ==
+
+== References ==
+
+== Further reading ==
+Aaboe, Asger (2001). Episodes from the Early History of Astronomy. Springer-Verlag. ISBN 0-387-95136-9.
+Berry, Arthur (1898). A Brief History of Astronomy – via Internet Archive.
+Dreyer, J. L. E. (1953) [1906]. History of Astronomy from Thales to Kepler (2nd ed.). Dover Publications.
+Eastwood, Bruce (2002). The Revival of Planetary Astronomy in Carolingian and Post-Carolingian Europe. Variorum Collected Studies Series. Vol. CS 279. Ashgate. ISBN 0-86078-868-7.
+Hodson, F. R., ed. (1974). The Place of Astronomy in the Ancient World: A Joint Symposium of the Royal Society and the British Academy. Oxford University Press. ISBN 0-19-725944-8.
+Hoskin, Michael (2003). The History of Astronomy: A Very Short Introduction. Oxford University Press. ISBN 0-19-280306-9.
+Hoskin, Michael (2011). Discoverers of the Universe: William and Caroline Herschel. Princeton University Press. ISBN 978-0691148335.
+Magli, Giulio (2004). "On the possible discovery of precessional effects in ancient astronomy". arXiv:physics/0407108.
+Neugebauer, Otto (1969) [1957]. The Exact Sciences in Antiquity (2 ed.). Dover Publications. ISBN 978-0-486-22332-2.
+Pannekoek, Anton (1989). A History of Astronomy. Dover Publications.
+Walker, Christopher, ed. (1996). Astronomy before the telescope. British Museum Press. ISBN 0-7141-1746-3.
+
+== External links ==
+ Media related to History of astronomy at Wikimedia Commons
+Astronomy & Empire, BBC Radio 4 discussion with Simon Schaffer, Kristen Lippincott & Allan Chapman (In Our Time, May 4, 2006)
+Bibliothèque numérique de l'Observatoire de Paris (Digital library of the Paris Observatory)
+Caelum Antiquum: Ancient Astronomy and Astrology Resources on LacusCurtius
+Mesoamerican Archaeoastronomy:  A Review of Contemporary Understandings of Prehispanic Astronomical Knowledge
+UNESCO-IAU Portal to the Heritage of Astronomy

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+
+The origins of astronomy can be found in Mesopotamia, the "land between the rivers" Tigris and Euphrates, where the ancient kingdoms of Sumer, Assyria, and Babylonia were located. A form of writing known as cuneiform emerged among the Sumerians around 3500–3000 BC. Our knowledge of Sumerian astronomy is indirect, via the earliest Babylonian star catalogues dating from about 1200 BC. The fact that many star names appear in Sumerian suggests a continuity reaching into the Early Bronze Age. Astral theology, which gave planetary gods an important role in Mesopotamian mythology and religion, began with the Sumerians. They also used a sexagesimal (base 60) place-value number system, which simplified the task of recording very large and very small numbers. The modern practice of dividing a circle into 360 degrees, or an hour into 60 minutes, began with the Sumerians. For more information, see the articles on Babylonian numerals and mathematics.
+Mesopotamia is worldwide the place of the earliest known astronomer and poet by name: Enheduanna, Akkadian high priestess to the lunar deity Nanna/Sin and princess, daughter of Sargon the Great (c. 2334 – c. 2279 BCE). She had the Moon tracked in her chambers and wrote poems about her divine Moon.
+Classical sources frequently use the term Chaldeans for the astronomers of Mesopotamia, who were originally a people, before being identified with priest-scribes specializing in astrology and other forms of divination.
+The first evidence of recognition that astronomical phenomena are periodic and of the application of mathematics to their prediction is Babylonian. Tablets dating back to the Old Babylonian period document the application of mathematics to the variation in the length of daylight over a solar year. Centuries of Babylonian observations of celestial phenomena are recorded in the series of cuneiform tablets known as the Enūma Anu Enlil. The oldest significant astronomical text that we possess is Tablet 63 of the Enūma Anu Enlil, the Venus tablet of Ammi-saduqa, which lists the first and last visible risings of Venus over a period of about 21 years and is the earliest evidence that the phenomena of a planet were recognized as periodic. The MUL.APIN contains catalogues of stars and constellations as well as schemes for predicting heliacal risings and the settings of the planets, lengths of daylight measured by a water clock, gnomon, shadows, and intercalations. The Babylonian GU text arranges stars in 'strings' that lie along declination circles and thus measure right-ascensions or time-intervals, and also employs the stars of the zenith, which are also separated by given right-ascensional differences.
+A significant increase in the quality and frequency of Babylonian observations appeared during the reign of Nabonassar (747–733 BC). The systematic records of ominous phenomena in Babylonian astronomical diaries that began at this time allowed for the discovery of a repeating 18-year cycle of lunar eclipses, for example. The Greek astronomer Ptolemy later used Nabonassar's reign to fix the beginning of an era, since he felt that the earliest usable observations began at this time.
+The last stages in the development of Babylonian astronomy took place during the time of the Seleucid Empire (323–60 BC). In the 3rd century BC, astronomers began to use "goal-year texts" to predict the motions of the planets. These texts compiled records of past observations to find repeating occurrences of ominous phenomena for each planet. About the same time, or shortly afterwards, astronomers created mathematical models that allowed them to predict these phenomena directly, without consulting records. A notable Babylonian astronomer from this time was Seleucus of Seleucia, who was a supporter of the heliocentric model.
+Babylonian astronomy was the basis for much of what was done in Greek and Hellenistic astronomy, in classical Indian astronomy, in Sassanian Iran, in Byzantium, in Syria, in Islamic astronomy, in Central Asia, and in Western Europe.
+
+=== India ===
+
+Astronomy in the Indian subcontinent dates back to the period of Indus Valley Civilisation during 3rd millennium BC, when it was used to create calendars. As the Indus Valley Civilization did not leave behind written documents, the oldest extant Indian astronomical text is the Vedanga Jyotisha, dating from the Vedic period. The Vedanga Jyotisha is attributed to Lagadha and has an internal date of approximately 1350 BC, and describes rules for tracking the motions of the Sun and the Moon for the purposes of ritual. It is available in two recensions, one belonging to the Rig Veda, and the other to the Yajur Veda. According to the Vedanga Jyotisha, in a yuga or "era", there are 5 solar years, 67 lunar sidereal cycles, 1,830 days, 1,835 sidereal days, and 62 synodic months. During the sixth century, astronomy was influenced by the Greek and Byzantine astronomical traditions.
+Aryabhata (476–550), in his magnum opus Aryabhatiya (499), propounded a computational system based on a planetary model in which the Earth was taken to be spinning on its axis and the periods of the planets were given with respect to the Sun. He accurately calculated many astronomical constants, such as the periods of the planets, times of the solar and lunar eclipses, and the instantaneous motion of the Moon. Early followers of Aryabhata's model included Varāhamihira, Brahmagupta, and Bhāskara II.
+Astronomy was advanced during the Shunga Empire, and many star catalogues were produced during this time. The Shunga period is known as the "Golden age of astronomy in India".
+It saw the development of calculations for the motions and places of various planets, their rising and setting, conjunctions, and the calculation of eclipses.
+By the sixth century, Indian astronomers believed that comets were celestial bodies that re-appeared periodically. This was the view expressed in the sixth century by the astronomers Varahamihira and Bhadrabahu. The tenth-century astronomer Bhattotpala listed the names and estimated periods of certain comets, but it is not known how these figures were calculated or how accurate they were.
+
+=== Greece and Hellenistic world ===

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+The Ancient Greeks developed astronomy, which they treated as a branch of mathematics, to a highly sophisticated level. The first geometrical, three-dimensional models to explain the apparent motion of the planets were developed in the 4th century BC by Eudoxus of Cnidus and Callippus of Cyzicus. Their models were based on nested homocentric spheres centered upon the Earth. Their younger contemporary Heraclides Ponticus proposed that the Earth rotates around its axis.
+A different approach to celestial phenomena was taken by natural philosophers such as Plato and Aristotle. They were less concerned with developing mathematical predictive models than with developing an explanation of the reasons for the motions of the Cosmos. In his Timaeus, Plato described the universe as a spherical body divided into circles carrying the planets and governed according to harmonic intervals by a world soul. Aristotle, drawing on the mathematical model of Eudoxus, proposed that the universe was made of a complex system of concentric spheres, whose circular motions combined to carry the planets around the Earth. This basic cosmological model prevailed, in various forms, until the 16th century.
+In the 3rd century BC Aristarchus of Samos was the first to suggest a heliocentric system, although only fragmentary descriptions of his idea survive. Eratosthenes estimated the circumference of the Earth with great accuracy (see also: history of geodesy).
+Greek geometrical astronomy developed away from the model of concentric spheres to employ more complex models in which an eccentric circle would carry around a smaller circle, called an epicycle which in turn carried around a planet. The first such model is attributed to Apollonius of Perga and further developments in it were carried out in the 2nd century BC by Hipparchus of Nicea. Hipparchus made a number of other contributions, including the first measurement of precession and the compilation of the first star catalog in which he proposed our modern system of apparent magnitudes.
+The Antikythera mechanism, an ancient Greek astronomical observational device for calculating the movements of the Sun and the Moon, possibly the planets, dates from about 150–100 BC, and was the first ancestor of an astronomical computer. It was discovered in an ancient shipwreck off the Greek island of Antikythera, between Kythera and Crete. The device became famous for its use of a differential gear, previously believed to have been invented in the 16th century, and the miniaturization and complexity of its parts, comparable to a clock made in the 18th century. The original mechanism is displayed in the Bronze collection of the National Archaeological Museum of Athens, accompanied by a replica.
+
+=== Ptolemaic system ===
+
+Depending on the historian's viewpoint, the acme or corruption of Classical physical astronomy is seen with Ptolemy, a Greco-Roman astronomer from Alexandria of Egypt, who wrote the classic comprehensive presentation of geocentric astronomy, the Megale Syntaxis (Great Synthesis), better known by its Arabic title Almagest, which had a lasting effect on astronomy up to the Renaissance. In his Planetary Hypotheses, Ptolemy ventured into the realm of cosmology, developing a physical model of his geometric system, in a universe many times smaller than the more realistic conception of Aristarchus of Samos four centuries earlier.
+
+=== Egypt ===
+
+Megalithic structures located in Nabta Playa, Upper Egypt featured astronomy, calendar arrangements in alignment with the heliacal rising of Sirius and supported calibration the yearly calendar for the annual Nile flood. These practices have been linked with the emergence of cosmology in Old Kingdom Egypt.
+The precise orientation of the Egyptian pyramids affords a lasting demonstration of the high degree of technical skill in watching the heavens attained in the 3rd millennium BC. It has been shown the Pyramids were aligned towards the pole star, which, because of the precession of the equinoxes, was at that time Thuban, a faint star in the constellation of Draco. Evaluation of the site of the temple of Amun-Re at Karnak, taking into account the change over time of the obliquity of the ecliptic, has shown that the Great Temple was aligned on the rising of the midwinter Sun. The length of the corridor down which sunlight would travel would have limited illumination at other times of the year. The Egyptians also found the position of Sirius (the dog star), who they believed was Anubis, their jackal-headed god, moving through the heavens. Its position was critical to their civilisation as when it rose heliacal in the east before sunrise it foretold the flooding of the Nile. It is also the origin of the phrase "dog days of summer".
+Astronomy played a considerable part in religious matters for fixing the dates of festivals and determining the hours of the night. The titles of several temple books are preserved recording the movements and phases of the Sun, Moon, and stars. The rising of Sirius (Egyptian: Sopdet, Greek: Sothis) at the beginning of the inundation was a particularly important point to fix in the yearly calendar.
+Writing in the Roman era, Clement of Alexandria gives some idea of the importance of astronomical observations to the sacred rites:

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+---
+
+And after the Singer advances the Astrologer (ὡροσκόπος), with a horologium (ὡρολόγιον) in his hand, and a palm (φοίνιξ), the symbols of astrology. He must know by heart the Hermetic astrological books, which are four in number. Of these, one is about the arrangement of the fixed stars that are visible; one on the positions of the Sun and Moon and five planets; one on the conjunctions and phases of the Sun and Moon; and one concerns their risings.
+The Astrologer's instruments (horologium and palm) are a plumb line and sighting instrument. They have been identified with two inscribed objects in the Berlin Museum; a short handle from which a plumb line was hung, and a palm branch with a sight-slit in the broader end. The latter was held close to the eye, the former in the other hand, perhaps at arm's length. The "Hermetic" books which Clement refers to are the Egyptian theological texts, which probably have nothing to do with Hellenistic Hermetism.
+From the tables of stars on the ceiling of the tombs of Rameses VI and Rameses IX it seems that for fixing the hours of the night a man seated on the ground faced the Astrologer in such a position that the line of observation of the pole star passed over the middle of his head. On the different days of the year each hour was determined by a fixed star culminating or nearly culminating in it, and the position of these stars at the time is given in the tables as in the centre, on the left eye, on the right shoulder, etc. According to the texts, in founding or rebuilding temples the north axis was determined by the same apparatus, and we may conclude that it was the usual one for astronomical observations. In careful hands it might give results of a high degree of accuracy.
+
+=== China ===
+
+The astronomy of East Asia began in China. Solar term was completed in Warring States period. The knowledge of Chinese astronomy was introduced into East Asia.
+Astronomy in China has a long history. Detailed records of astronomical observations were kept from about the 6th century BC, until the introduction of Western astronomy and the telescope in the 17th century. Chinese astronomers were able to precisely predict eclipses.
+Much of early Chinese astronomy was for the purpose of timekeeping. The Chinese used a lunisolar calendar, but because the cycles of the Sun and the Moon are different, astronomers often prepared new calendars and made observations for that purpose.
+Astrological divination was also an important part of astronomy. Astronomers took careful note of "guest stars" (Chinese: 客星; pinyin: kèxīng; lit. 'guest star') which suddenly appeared among the fixed stars. They were the first to record a supernova, in the Astrological Annals of the Houhanshu in 185 AD. Also, the supernova that created the Crab Nebula in 1054 is an example of a "guest star" observed by Chinese astronomers, although it was not recorded by their European contemporaries. Ancient astronomical records of phenomena like supernovae and comets are sometimes used in modern astronomical studies.
+The world's first star catalogue was made by Gan De, a Chinese astronomer, in the 4th century BC.
+
+=== Mesoamerica ===
+
+Maya astronomical codices include detailed tables for calculating phases of the Moon, the recurrence of eclipses, and the appearance and disappearance of Venus as morning and evening star. The Maya based their calendrics in the carefully calculated cycles of the Pleiades, the Sun, the Moon, Venus, Jupiter, Saturn, Mars, and also they had a precise description of the eclipses as depicted in the Dresden Codex, as well as the ecliptic or zodiac, and the Milky Way was crucial in their Cosmology. A number of important Maya structures are believed to have been oriented toward the extreme risings and settings of Venus. To the ancient Maya, Venus was the patron of war and many recorded battles are believed to have been timed to the motions of this planet. Mars is also mentioned in preserved astronomical codices and early mythology.
+Although the Maya calendar was not tied to the Sun, John Teeple has proposed that the Maya calculated the solar year to somewhat greater accuracy than the Gregorian calendar. Both astronomy and an intricate numerological scheme for the measurement of time were vitally important components of Maya religion.
+The Maya believed that the Earth was the center of all things, and that the stars, moons, and planets were gods. They believed that their movements were the gods traveling between the Earth and other celestial destinations. Many key events in Maya culture were timed around celestial events, in the belief that certain gods would be present.
+
+== Middle Ages ==
+
+=== Middle East ===

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+---
+title: "History of astronomy"
+chunk: 6/11
+source: "https://en.wikipedia.org/wiki/History_of_astronomy"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:16.412764+00:00"
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+---
+
+The Arabic and the Persian world under Islam had become highly cultured, and many important works of knowledge from Greek astronomy, Indian astronomy, and Persian astronomy were translated into Arabic, which were then used and stored in libraries throughout the area. An important contribution by Islamic astronomers was their emphasis on observational astronomy. This led to the emergence of the first astronomical observatories in the Muslim world by the early 9th century. Zij star catalogues were produced at these observatories.
+In the ninth century, Persian astrologer Albumasar was thought to be one of the greatest astrologer at that time. His practical manuals for training astrologers profoundly influenced Muslim intellectual history and, through translations, that of western Europe and Byzantium In the 10th century, Albumasar's "Introduction" was one of the most important sources for the recovery of Aristotle for medieval European scholars. Abd al-Rahman al-Sufi (Azophi) carried out observations on the stars and described their positions, magnitudes, brightness, and colour and drawings for each constellation in his Book of Fixed Stars. He also gave the first descriptions and pictures of "A Little Cloud" now known as the Andromeda Galaxy. He mentions it as lying before the mouth of a Big Fish, an Arabic constellation. This "cloud" was apparently commonly known to the Isfahan astronomers, very probably before 905 AD. The first recorded mention of the Large Magellanic Cloud was also given by al-Sufi. In 1006, Ali ibn Ridwan observed SN 1006, the brightest supernova in recorded history, and left a detailed description of the temporary star.
+In the late tenth century, a huge observatory was built near Tehran, Iran, by the astronomer Abu-Mahmud al-Khujandi who observed a series of meridian transits of the Sun, which allowed him to calculate the tilt of the Earth's axis relative to the Sun. He noted that measurements by earlier (Indian, then Greek) astronomers had found higher values for this angle, possible evidence that the axial tilt is not constant but was in fact decreasing. In 11th-century Persia, Omar Khayyám compiled many tables and performed a reformation of the calendar that was more accurate than the Julian and came close to the Gregorian.
+Other Muslim advances in astronomy included the collection and correction of previous astronomical data, resolving significant problems in the Ptolemaic model, the development of the universal latitude-independent astrolabe by Arzachel, the invention of numerous other astronomical instruments, Ja'far Muhammad ibn Mūsā ibn Shākir's belief that the heavenly bodies and celestial spheres were subject to the same physical laws as Earth, and the introduction of empirical testing by Ibn al-Shatir, who produced the first model of lunar motion which matched physical observations.
+Natural philosophy (particularly Aristotelian physics) was separated from astronomy by Ibn al-Haytham (Alhazen) in the 11th century, by Ibn al-Shatir in the 14th century, and Qushji in the 15th century.
+
+=== India ===
+
+Bhāskara II (1114–1185) was the head of the astronomical observatory at Ujjain, continuing the mathematical tradition of Brahmagupta. He wrote the Siddhantasiromani which consists of two parts: Goladhyaya (sphere) and Grahaganita (mathematics of the planets). He also calculated the time taken for the Sun to orbit the Earth to nine decimal places. The Buddhist University of Nalanda at the time offered formal courses in astronomical studies.
+Other important astronomers from India include Madhava of Sangamagrama, Nilakantha Somayaji and Jyeshtadeva, who were members of the Kerala school of astronomy and mathematics from the 14th century to the 16th century. Nilakantha Somayaji, in his Aryabhatiyabhasya, a commentary on Aryabhata's Aryabhatiya, developed his own computational system for a partially heliocentric planetary model, in which Mercury, Venus, Mars, Jupiter and Saturn orbit the Sun, which in turn orbits the Earth, similar to the Tychonic system later proposed by Tycho Brahe in the late 16th century. Nilakantha's system, however, was mathematically more efficient than the Tychonic system, due to correctly taking into account the equation of the centre and latitudinal motion of Mercury and Venus. Most astronomers of the Kerala school of astronomy and mathematics who followed him accepted his planetary model.
+
+=== Western Europe ===

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+---
+title: "History of astronomy"
+chunk: 7/11
+source: "https://en.wikipedia.org/wiki/History_of_astronomy"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:16.412764+00:00"
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+---
+
+After the significant contributions of Greek scholars to the development of astronomy, it entered a relatively static era in Western Europe from the Roman era through the 12th century. This lack of progress has led some astronomers to assert that nothing happened in Western European astronomy during the Middle Ages.  Recent investigations, however, have revealed a more complex picture of the study and teaching of astronomy in the period from the 4th to the 16th centuries.
+Western Europe entered the Middle Ages with great difficulties that affected the continent's intellectual production. The advanced astronomical treatises of classical antiquity were written in Greek, and with the decline of knowledge of that language, only simplified summaries and practical texts were available for study. The most influential writers to pass on this ancient tradition in Latin were Macrobius, Pliny, Martianus Capella, and Calcidius.  In the 6th century Bishop Gregory of Tours noted that he had learned his astronomy from reading Martianus Capella, and went on to employ this rudimentary astronomy to describe a method by which monks could determine the time of prayer at night by watching the stars.
+In the 7th century the English monk Bede of Jarrow published an influential text, On the Reckoning of Time, providing churchmen with the practical astronomical knowledge needed to compute the proper date of Easter using a procedure called the computus. This text remained an important element of the education of clergy from the 7th century until well after the rise of the Universities in the 12th century.
+The range of surviving ancient Roman writings on astronomy and the teachings of Bede and his followers began to be studied in earnest during the revival of learning sponsored by the emperor Charlemagne. By the 9th century rudimentary techniques for calculating the position of the planets were circulating in Western Europe; medieval scholars recognized their flaws, but texts describing these techniques continued to be copied, reflecting an interest in the motions of the planets and in their astrological significance.
+Building on this astronomical background, in the 10th century European scholars such as Gerbert of Aurillac began to travel to Spain and Sicily to seek out learning which they had heard existed in the Arabic-speaking world. There they first encountered various practical astronomical techniques concerning the calendar and timekeeping, most notably those dealing with the astrolabe. Soon scholars such as Hermann of Reichenau were writing texts in Latin on the uses and construction of the astrolabe and others, such as Walcher of Malvern, were using the astrolabe to observe the time of eclipses in order to test the validity of computistical tables.
+By the 12th century, scholars were traveling to Spain and Sicily to seek out more advanced astronomical and astrological texts, which they translated into Latin from Arabic and Greek to further enrich the astronomical knowledge of Western Europe. The arrival of these new texts coincided with the rise of the universities in medieval Europe, in which they soon found a home. Reflecting the introduction of astronomy into the universities, John of Sacrobosco wrote a series of influential introductory astronomy textbooks: the Sphere, a Computus, a text on the Quadrant, and another on Calculation.
+In the 14th century, Nicole Oresme, later bishop of Liseux, showed that neither the scriptural texts nor the physical arguments advanced against the movement of the Earth were demonstrative and adduced the argument of simplicity for the theory that the Earth moves, and not the heavens. However, he concluded "everyone maintains, and I think myself, that the heavens do move and not the earth: For God hath established the world which shall not be moved." In the 15th century, Cardinal Nicholas of Cusa suggested in some of his scientific writings that the Earth revolved around the Sun, and that each star is itself a distant sun.
+
+== Renaissance and Early Modern Europe ==
+
+=== Copernican Revolution ===

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+title: "History of astronomy"
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+
+During the renaissance period, astronomy began to undergo a revolution in thought known as the Copernican Revolution, which gets the name from the astronomer Nicolaus Copernicus, who proposed a heliocentric system, in which the planets revolved around the Sun and not the Earth. His De revolutionibus orbium coelestium was published in 1543. While in the long term this was a very controversial claim, in the very beginning it only brought minor controversy. The theory became the dominant view because many figures, most notably Galileo Galilei, Johannes Kepler and Isaac Newton championed and improved upon the work. Other figures also aided this new model despite not believing the overall theory, like Tycho Brahe, with his well-known observations.
+Brahe, a Danish noble, was an essential astronomer in this period. He came on the astronomical scene with the publication of De nova stella, in which he disproved conventional wisdom on the supernova SN 1572 (As bright as Venus at its peak, SN 1572 later became invisible to the naked eye, disproving  the Aristotelian doctrine of the immutability of the heavens.) He also created the Tychonic system, where the Sun and Moon and the stars revolve around the Earth, but the other five planets revolve around the Sun. This system blended the mathematical benefits of the Copernican system with the "physical benefits" of the Ptolemaic system. This was one of the systems people believed in when they did not accept heliocentrism, but could no longer accept the Ptolemaic system. He is most known for his highly accurate observations of the stars and the planets. Later he moved to Prague and continued his work. In Prague he was at work on the Rudolphine Tables, that were not finished until after his death. The Rudolphine Tables was a star map designed to be more accurate than either the Alfonsine tables, made in the 1300s, and the Prutenic Tables, which were inaccurate. He was assisted at this time by his assistant Johannes Kepler, who would later use his observations to finish Brahe's works and for his theories as well.
+After the death of Brahe, Kepler was deemed his successor and was given the job of completing Brahe's uncompleted works, like the Rudolphine Tables. He completed the Rudolphine Tables in 1624, although it was not published for several years. Like many other figures of this era, he was subject to religious and political troubles, like the Thirty Years' War, which led to chaos that almost destroyed some of his works. Kepler was, however, the first to attempt to derive mathematical predictions of celestial motions from assumed physical causes. He discovered the three Kepler's laws of planetary motion that now carry his name, those laws being as follows:
+
+The orbit of a planet is an ellipse with the Sun at one of the two foci.
+A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time.
+The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.
+With these laws, he managed to improve upon the existing heliocentric model. The first two were published in 1609. Kepler's contributions improved upon the overall system, giving it more credibility because it adequately explained events and could cause more reliable predictions. Before this, the Copernican model was just as unreliable as the Ptolemaic model.  This improvement came because Kepler realized the orbits were not perfect circles, but ellipses.

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+title: "History of astronomy"
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+category: "reference"
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+date_saved: "2026-05-05T03:59:16.412764+00:00"
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+---
+
+=== Galileo ===
+ The invention of the telescope in 1608 revolutionized the study of astronomy. Galileo Galilei was among the first to use a telescope to observe the sky, after constructing a 20x refractor telescope. He discovered the four largest moons of Jupiter in 1610, which are now collectively known as the Galilean moons, in his honor. This discovery was the first known observation of satellites orbiting another planet. He also found that the Moon had craters and observed, and correctly explained sunspots, and that Venus exhibited a full set of phases resembling lunar phases. Galileo argued that these facts demonstrated incompatibility with the Ptolemaic model, which could not explain the phenomenon and would even contradict it. With Jupiter's moons, he demonstrated that the Earth does not have to have everything orbiting it and that other bodies could orbit another planet, such as the Earth orbiting the Sun. In the Ptolemaic system the celestial bodies were supposed to be perfect so such objects should not have craters or sunspots. The phases of Venus could only happen in the event that Venus orbits around the Sun, which did not happen in the Ptolemaic system. He, as the most famous example, had to face challenges from church officials, more specifically the Roman Inquisition. They accused him of heresy because these beliefs went against the teachings of the Roman Catholic Church and were challenging the Catholic church's authority when it was at its weakest. While he was able to avoid punishment for a little while he was eventually tried and pled guilty to heresy in 1633. Although this came at some expense, his book was banned, and he was put under house arrest until he died in 1642. Sir Isaac Newton developed further ties between physics and astronomy through his law of universal gravitation. Realizing that the same force that attracts objects to the surface of the Earth held the Moon in orbit around the Earth, Newton was able to explain – in one theoretical framework – all known gravitational phenomena. In his Philosophiæ Naturalis Principia Mathematica, he derived Kepler's laws from first principles. Those first principles are as follows:
+In an inertial frame of reference, an object either remains at rest or continues to move at constant velocity, unless acted upon by a force.
+In an inertial reference frame, the vector sum of the forces F on an object is equal to the mass m of that object multiplied by the acceleration a of the object: F = ma. (It is assumed here that the mass m is constant)
+When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.
+Thus while Kepler explained how the planets moved, Newton accurately managed to explain why the planets moved the way they do. Newton's theoretical developments laid many of the foundations of modern physics.
+
+=== Completing the Solar System ===
+
+Outside of England, Newton's theory took some time to become established. René Descartes' theory of vortices held sway in France, and Christiaan Huygens, Gottfried Wilhelm Leibniz and Jacques Cassini accepted only parts of Newton's system, preferring their own philosophies. Voltaire published a popular account in 1738. In 1748, the French Academy of Sciences offered a reward for solving the question of the perturbations of Jupiter and Saturn, which was eventually done by Euler and Lagrange. Laplace completed the theory of the planets, publishing from 1798 to 1825. The early origins of the solar nebular model of planetary formation had begun.
+Edmond Halley succeeded John Flamsteed as Astronomer Royal in England and succeeded in predicting the return of the comet that bears his name in 1758. William Herschel found the first new planet, Uranus, to be observed in modern times in 1781.
+At first, astronomical thought in America was based on Aristotelian philosophy, but interest in the new astronomy began to appear in Almanacs as early as 1659. The gap between the planets Mars and Jupiter disclosed by the Titius–Bode law was filled by the discovery of the asteroids Ceres and Pallas in 1801 and 1802 with many more following.

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+title: "History of astronomy"
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+date_saved: "2026-05-05T03:59:16.412764+00:00"
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+---
+
+=== Stellar astronomy ===
+Cosmic pluralism is the name given to the idea that the stars are distant suns, perhaps with their own planetary systems.
+Ideas in this direction were expressed in antiquity, by Anaxagoras and  by Aristarchus of Samos, but did not find mainstream acceptance. The first astronomer of the European Renaissance to suggest that the stars were distant suns was Giordano Bruno in his De l'infinito universo et mondi (1584). This idea was among the charges brought against him by the Inquisition. Telescopic observations by Galileo Galilei showed that the Milky Way was a great concentration of individual stars. The idea of many stars became mainstream in the later 17th century, especially following the publication of Conversations on the Plurality of Worlds by Bernard Le Bovier de Fontenelle (1686), and by the early 18th century it was the default working assumptions in stellar astronomy.
+The Italian astronomer Geminiano Montanari recorded observing variations in luminosity of the star Algol in 1667. Edmond Halley published the first measurements of the proper motion of a pair of nearby "fixed" stars, demonstrating that they had changed positions since the time of the ancient Greek astronomers Ptolemy and Hipparchus. William Herschel was the first astronomer to attempt to determine the distribution of stars in the sky. During the 1780s, he established a series of gauges in 600 directions and counted the stars observed along each line of sight. From this he deduced that the number of stars steadily increased toward one side of the sky, in the direction of the Milky Way core. His son John Herschel repeated this study in the southern hemisphere and found a corresponding increase in the same direction. In addition to his other accomplishments, William Herschel is noted for his discovery that some stars do not merely lie along the same line of sight, but are physical companions that form binary star systems.
+
+== Modern astronomy ==
+
+=== 19th century ===
+
+Pre-photography, data recording of astronomical data was limited by the human eye. In 1840, John W. Draper, a chemist, created the earliest known astronomical photograph of the Moon. And by the late 19th century thousands of photographic plates of images of planets, stars, and galaxies were created. Most photography had lower quantum efficiency (i.e. captured less of the incident photons) than human eyes but had the advantage of long integration times (100 ms for the human eye compared to hours for photos). This vastly increased the data available to astronomers, which led to the rise of human computers, famously the Harvard Computers, to track and analyze the data.
+Scientists began discovering forms of light which were invisible to the naked eye: X-rays, gamma rays, radio waves, microwaves, ultraviolet radiation, and infrared radiation. This had a major impact on astronomy, spawning the fields of infrared astronomy, radio astronomy, x-ray astronomy and finally gamma-ray astronomy. With the advent of spectroscopy it was proven that other stars were similar to the Sun, but with a range of temperatures, masses and sizes.
+The science of stellar spectroscopy was pioneered by Joseph von Fraunhofer and Angelo Secchi. By comparing the spectra of stars such as Sirius to the Sun, they found differences in the strength and number of their absorption lines—the dark lines in stellar spectra caused by the atmosphere's absorption of specific frequencies. In 1865, Secchi began classifying stars into spectral types. The first evidence of helium was observed on August 18, 1868, as a bright yellow spectral line with a wavelength of 587.49 nanometers in the spectrum of the chromosphere of the Sun. The line was detected by French astronomer Jules Janssen during a total solar eclipse in Guntur, India.
+The first direct measurement of the distance to a star (61 Cygni at 11.4 light-years) was made in 1838 by Friedrich Bessel using the parallax technique. Parallax measurements demonstrated the vast separation of the stars in the heavens. Observation of double stars gained increasing importance during the 19th century. In 1834, Friedrich Bessel observed changes in the proper motion of the star Sirius and inferred a hidden companion. Edward Pickering discovered the first spectroscopic binary in 1899 when he observed the periodic splitting of the spectral lines of the star Mizar in a 104-day period. Detailed observations of many binary star systems were collected by astronomers such as Friedrich Georg Wilhelm von Struve and S. W. Burnham, allowing the masses of stars to be determined from the computation of orbital elements. The first solution to the problem of deriving an orbit of binary stars from telescope observations was made by Felix Savary in 1827.
+In 1847, Maria Mitchell discovered a comet using a telescope.
+
+=== 20th century ===

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+---
+title: "History of aviation"
+chunk: 1/15
+source: "https://en.wikipedia.org/wiki/History_of_aviation"
+category: "reference"
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+date_saved: "2026-05-05T03:59:18.099578+00:00"
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+---
+
+The history of aviation spans over two millennia, from the earliest innovations like kites and attempts at tower jumping to supersonic and hypersonic flight in powered, heavier-than-air jet aircraft. Kite flying in China, dating back several hundred years BC, is considered the earliest example of man-made flight. In the 15th-century Leonardo da Vinci designed several flying machines incorporating aeronautical concepts, but they were unworkable due to the limitations of contemporary knowledge.
+In the late 18th century, the Montgolfier brothers invented the hot-air balloon which soon led to manned flights. At almost the same time, the discovery of hydrogen gas led to the invention of the hydrogen balloon. Various theories in mechanics by physicists during the same period, such as fluid dynamics and Newton's laws of motion, led to the development of modern aerodynamics; most notably by Sir George Cayley. Balloons, both free-flying and tethered, began to be used for military purposes from the end of the 18th century, with France establishing balloon companies during the French Revolution.
+In the 19th century, especially the second half, experiments with gliders provided the basis for learning the dynamics of winged aircraft; most notably by Cayley, Otto Lilienthal, and Octave Chanute. By the early 20th century, advances in engine technology and aerodynamics made controlled, powered, manned heavier-than-air flight possible for the first time. In 1903, following their pioneering research and experiments with wing design and aircraft control, the Wright brothers successfully incorporated all of the required elements to create and fly the first aeroplane. The basic configuration with its characteristic cruciform tail was established by 1909, followed by rapid design and performance improvements aided by the development of more powerful engines.
+The first vessels of the air were the rigid steerable balloons pioneered by Ferdinand von Zeppelin that became synonymous with airships and dominated long-distance flight until the 1930s, when large flying boats became popular for trans-oceanic routes. After World War II, the flying boats were in turn replaced by airplanes operating from land, made far more capable first by improved propeller engines, then by jet engines, which revolutionized both civilian air travel and military aviation.
+In the latter half of the 20th century, the development of digital electronics led to major advances in flight instrumentation and "fly-by-wire" systems. The 21st century has seen the widespread use of pilotless drones for military, commercial, and recreational purposes. With computerized controls, inherently unstable aircraft designs, such as flying wings, have also become practical.
+
+== Etymology ==
+The term aviation, is a noun of action from the stem of Latin avis "bird" with the suffix -ation meaning action or progress. It was coined in 1863 by French pioneer Guillaume Joseph Gabriel de La Landelle (1812–1886) in Aviation ou Navigation aérienne sans ballons.
+
+== Primitive beginnings ==
+
+=== Tower jumping ===
+
+Since ancient times, there have been stories of men strapping birdlike wings, stiffened cloaks, or other devices to themselves and attempting to fly, typically by jumping off a tower. The Greek legends of Daedalus and Icarus are some of the earliest known. Others originated in ancient Asia and the European Middle Ages. During this early period, the concepts of lift, stability, and control were not well understood, and most attempts resulted in serious injuries or death.
+The Andalusian scientist Abbas ibn Firnas (810–887 AD) attempted to fly in Córdoba, Spain, by covering his body with vulture feathers and attached two wings to his arms. The 17th-century Algerian historian Ahmed Mohammed al-Maqqari, quoting a poem by Muhammad I of Córdoba's 9th-century court poet Mu'min ibn Said, recounts that Firnas flew some distance before landing with some injuries, attributed to his lacking a tail (as birds use them to land). In the 12th century, William of Malmesbury wrote that Eilmer of Malmesbury, an 11th-century Benedictine monk, attached wings to his hands and feet and flew a short distance, but broke both legs while landing, also having neglected to make himself a tail.
+Many others made well-documented jumps in the following centuries. As late as 1811, Albrecht Berblinger constructed an ornithopter and jumped into the Danube at Ulm.
+
+=== Kites ===
+
+The kite may have been the first form of man-made heavier-than-air aircraft. It was invented in China possibly as far back as the 5th century BC. by Mozi (Mo Di) and Lu Ban (Gongshu Ban). Evidence to support this finding stands with materials commonly found and ideal for kite building located in China. These are materials such as "silk fabric for sail material, fine, high-tensile-strength silk for flying line, and resilient bamboo for…framework" The reason these materials were so perfect for building kites is largely due to the structure of the materials themselves. Bamboo being a strong, hollow material, largely resembled the hollow bones in birds, which allow for less weight, making flight easier. Some kites were fitted with strings and whistles to make musical sounds while flying. Ancient and mediaeval Chinese sources describe kites being used to measure distances, test the wind, lift men, signal, and communicate and send messages. Later designs often depicted images of flying insects, birds, and other beasts, both real and mythical.
+Kites spread from China around the world. After being introduced into the rest of Asia, the kite further evolved into the fighter kite, which has an abrasive line used to cut down other kites. The most notable fighter kite designs originated in India and Japan
+
+==== Man-lifting kites ====
+Man-lifting kites are believed to have been used extensively in ancient China for civil and military purposes and sometimes enforced as a punishment. An early recorded flight was that of the prisoner Yuan Huangtou, a Chinese prince, in the 6th century AD. Stories of man-lifting kites can be found in Japan, following the introduction of the kite from China around the seventh century AD. For a period, there was a Japanese law against man-carrying kites.

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+---
+title: "History of aviation"
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+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:18.099578+00:00"
+instance: "kb-cron"
+---
+
+=== Rotor wings ===
+The use of a rotor for vertical flight has existed since 400 BC in the form of the bamboo-copter, an ancient Chinese toy. The similar "moulinet à noix" (rotor on a nut) appeared in Europe in the 14th century AD.
+
+=== Hot air balloons ===
+
+Since ancient times, the Chinese understood that hot air rises and applied the principle to a type of small hot air balloon called a sky lantern. A sky lantern consists of a paper balloon under or just inside which a small lamp is placed. Sky lanterns are traditionally launched for recreation and during festivals. According to Joseph Needham, such lanterns were found in China since the 3rd century BC. Their military use is attributed to the general Zhuge Liang (180–234 AD), who is said to have used them to scare the enemy troops.
+There is evidence that the Chinese also "solved the problem of aerial navigation" using balloons, hundreds of years before the 18th century.
+
+=== Renaissance ===
+
+Eventually, some investigators began to discover and define some of the basics of rational aircraft design. Most notable of these was Leonardo da Vinci, although his work remained unknown until 1797, and so had no influence on developments over the next three hundred years. While his designs are rational, they are not scientific. He particularly underestimated the amount of power that would be needed to propel a flying object, basing his designs on the flapping wings of a bird rather than an engine-powered propeller.
+Leonardo studied bird and bat flight, claiming the superiority of the latter owing to its unperforated wing. He analyzed these and anticipated many principles of aerodynamics. He understood that "An object offers as much resistance to the air as the air does to the object." Isaac Newton later defined this as the third law of motion in 1687.
+From the last years of the 15th century until 1505, Leonardo wrote about and sketched many designs for flying machines and mechanisms, including ornithopters, fixed-wing gliders, rotorcraft (perhaps inspired by whirligig toys), parachutes (in the form of a wooden-framed pyramidal tent) and a wind speed gauge. His early designs were man-powered and included ornithopters and rotorcraft; however, he came to realise the impracticality of this and later turned to controlled gliding flight, also sketching some designs powered by a spring.
+In an essay titled Sul volo (On flight), Leonardo describes a flying machine called "the bird" which he built from starched linen, leather joints, and raw silk thongs. In the Codex Atlanticus, he wrote, "Tomorrow morning, on the second day of January 1496, I will make the thong and the attempt." According to one commonly repeated, albeit presumably fictional story, in 1505 Leonardo or one of his pupils attempted to fly from the summit of Monte Ceceri.
+
+== Lighter than air ==
+
+=== Beginnings of modern theories ===
+Francesco Lana de Terzi proposed in Prodromo dell'Arte Maestra (1670) that large vessels could float in the atmosphere by applying the principles of a vacuum. Lana designed an airship with four huge copper foil spheres connected to support a rider's basket, a tail, and a steering rudder. Critics argued that the thin copper spheres could not sustain ambient air pressure, and further experiments proved that his idea was impossible.
+Using a vacuum to create lift is called a vacuum airship, but it is still impossible to build with the materials available today.
+In 1709, Bartolomeu de Gusmão approached King John V of Portugal and claimed to have discovered a way for airborne flight.
+Due to the King's illness, Gusmão's experiment was rescheduled from its initial 24 June 1709, date to 8 August. The experiment was carried out in front of the king and other nobles in the Casa da India yard, but the paper ship or device burned down before it could take flight.
+
+=== Balloons ===
+
+ 
+In France, five aviation firsts were accomplished between 4 June and 1 December 1783:

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+---
+title: "History of aviation"
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+category: "reference"
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+date_saved: "2026-05-05T03:59:18.099578+00:00"
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+---
+
+Almost as soon as they were invented, aeroplanes were used for military purposes. The first country to use them for military purposes was Italy, whose aircraft made reconnaissance, bombing and artillery correction flights in Libya during the Italian-Turkish war (September 1911 – October 1912). This war also saw Ottoman soldiers shoot down a warplane for the first time in history. The first warplane reconnaissance mission flown on 23 October 1911 by the Italian air force's Captain Carlo Piazza, and the first bombing mission was flown on 1 November 1911 by Italy's Second Lieutenant Giolio Gavotti. Bulgaria later followed this example. Its planes attacked and reconnoitred Ottoman positions during the First Balkan War 1912–13. The first war to see major use of aeroplanes in offensive, defensive and reconnaissance capabilities was World War I. The Allies and Central Powers both used aeroplanes and airships extensively.
+While the concept of using the aeroplane as an offensive weapon was generally discounted before World War I, the idea of using it for photography was one that was not lost on any of the major forces. All of the major forces in Europe had light aircraft, typically derived from pre-war sporting designs, attached to their reconnaissance departments. Radiotelephones were also being explored on aeroplanes, notably the SCR-68, as communication between pilots and ground commander grew more and more important.
+
+=== World War I (1914–1918) ===
+
+==== Combat schemes ====
+
+It was not long before aircraft were shooting at each other, but the lack of any sort of steady point for the gun was a problem. The French solved this problem when, in late 1914, Roland Garros attached a fixed machine gun to the front of his plane. Adolphe Pegoud became known as the first "ace", getting credit for five victories before also becoming the first ace to die in action, it was German Luftstreitkräfte Leutnant Kurt Wintgens who, on 1 July 1915, scored the very first aerial victory by a purpose-built fighter plane, with a synchronized machine gun.
+Aviators were styled as modern-day knights, doing individual combat with their enemies. Several pilots became famous for their air-to-air combat; the most well known is Manfred von Richthofen, better known as the "Red Baron", who shot down 80 planes in air-to-air combat with several different planes, the most celebrated of which was the Fokker Dr.I. On the Allied side, René Paul Fonck is credited with the most all-time victories at 75, even when later wars are considered.
+France, Britain, Germany, and Italy were the leading manufacturers of fighter planes that saw action during the war, with German aviation technologist Hugo Junkers showing the way to the future through his pioneering use of all-metal aircraft from late 1915.
+
+=== Between the World Wars (1918–1939) ===

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+---
+title: "History of aviation"
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+---
+
+The years between World War I and World War II saw great advancements in aircraft technology. Airplanes evolved from low-powered biplanes made from wood and fabric to sleek, high-powered monoplanes made of aluminum, based primarily on the founding work of Hugo Junkers during the World War I period and its adoption by American designer William Bushnell Stout and Soviet designer Andrei Tupolev.
+After World War I, experienced fighter pilots were eager to show off their skills. Many American pilots became barnstormers, flying into small towns across the country and showing off their flying abilities, as well as taking paying passengers for rides. Eventually, the barnstormers grouped into more organized displays. Air shows sprang up around the country, with air races, acrobatic stunts, and feats of air superiority. The air races drove engine and airframe development—the Schneider Trophy, for example, led to a series of ever faster and sleeker monoplane designs culminating in the Supermarine S.6B. With pilots competing for cash prizes, there was an incentive to go faster. Amelia Earhart was perhaps the most famous of those on the barnstorming/air show circuit. She was also the first female pilot to achieve records such as the crossing of the Atlantic and Pacific Oceans.
+Prizes for distance and speed records also drove development forwards. On 14 June 1919, Captain John Alcock and Lieutenant Arthur Brown co-piloted a Vickers Vimy non-stop from St. John's, Newfoundland to Clifden, Ireland, winning the £13,000 ($65,000). Northcliffe prize. Commercial aviation was introduced by Aircraft Transport and Travel (AT&T) in Britain, which began the first regular scheduled international flight in 1919. The first flight across the South Atlantic and the first aerial crossing using astronomical navigation, was made by the naval aviators Gago Coutinho and Sacadura Cabral in 1922, from Lisbon, Portugal, to Rio de Janeiro, Brazil, using an aircraft fitted with an artificial horizon for aeronautical use. In 1924, Major General Mason Patrick led a group of U.S. Army Air Service members to complete the first aerial circumnavigation of the world. This flight around the world came with many logistical challenges, traveling 26,343 miles over the span of 175 days. This flight led to improved foreign relations by promoting commercial collaboration, and greater public interest in aviation, prompting governments to put more resources into developing their aviation forces. On 21 May 1927, Charles Lindbergh received the Orteig Prize of $25,000 for the first solo non-stop crossing of the Atlantic. This caused what was known in aviation at the time as the "Lindbergh boom", which increased public interest in aviation.
+Australian Sir Charles Kingsford Smith was the first to fly across the larger Pacific Ocean in the Southern Cross. His crew left Oakland, California to make the first trans-Pacific flight to Australia, making three stops to complete the journey. Kingsford-Smith and his crew made their first stop in Hawaii from Oakland, California, and from Hawaii to Suva, Fiji. During the last segment of their journey from Fiji to Brisbane, Australia, they encountered severe thunderstorms, and were thrown nearly 140 miles off their course. The flight concluded on 9 June 1928 after flying 7,230 miles, Kingsford-Smith and his crew landed in Brisbane, Australia, receiving $25,000 from the Australian government for their achievement. Accompanying him were Australian aviator Charles Ulm as the relief pilot, and the Americans James Warner and Captain Harry Lyon (who were the radio operator, navigator and engineer). A week after they landed, Kingsford Smith and Ulm recorded a disc for Columbia talking about their trip. With Ulm, Kingsford Smith later continued his journey being the first in 1929 to circumnavigate the world, crossing the equator twice.
+The first lighter-than-air crossings of the Atlantic were made by airship in July 1919 by His Majesty's Airship R34 and crew when they flew from East Lothian, Scotland to Long Island, New York and then back to Pulham, England. By 1929, airship technology had advanced to the point that the first round-the-world flight was completed by the Graf Zeppelin in September and in October, the same aircraft inaugurated the first commercial transatlantic service. However, the age of the rigid airship ended following the destruction by fire of the zeppelin LZ 129 Hindenburg just before landing at Lakehurst, New Jersey on 6 May 1937, killing 35 of the 97 people aboard. Previous spectacular airship accidents, from the Wingfoot Express disaster (1919), the loss of the R101 (1930), the Akron (1933) and the Macon (1935) had already cast doubt on airship safety. The disasters of the U.S. Navy's rigids showed the importance of solely using helium as the lifting medium. Following the destruction of the Hindenburg, the remaining airship making international flights, the Graf Zeppelin was retired (June 1937). Its replacement, the rigid airship Graf Zeppelin II, made a number of flights, primarily over Germany, from 1938 to 1939, but was grounded when Germany began World War II. Both remaining German zeppelins were scrapped in 1940 to supply metal for the German Luftwaffe air force.
+Meanwhile, Germany, which was restricted by the Treaty of Versailles in its development of powered aircraft, developed gliding as a sport, especially at the Wasserkuppe, during the 1920s. In its various forms, in the 21st-century sailplane aviation now has over 400,000 participants.

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+title: "History of aviation"
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+
+In 1929, Jimmy Doolittle developed flight instruments . 1929 also saw the first flight of by far the largest plane ever built until then: the Dornier Do X with a wingspan of 48 m. On its 70th test flight on 21 October 1929, there were 169 people on board, a record that was not broken for 20 years.
+In 1923, The first successful rotorcraft appeared in the form of the autogyro, invented by Spanish engineer Juan de la Cierva and first flown in 1919. In this design, the rotor is not powered but spins freely as it moves through the air, while a separate engine powers the aircraft to move forward. This was the basis of further development and prototypes that led to the creation of the helicopter. In 1930 Corradino D'Ascanio, an Italian engineer, developed a coaxial helicopter with the important inclusion of three small propellers on the craft, which controlled the pitch, roll, and yaw of the aircraft. Later helicopters saw several adjustments to their rotors but the first modern helicopter was not constructed until 1947 by Igor Sikorsky
+Only five years after the German Dornier Do-X had flown, Tupolev designed the largest aircraft of the 1930s era, the Maksim Gorky in the Soviet Union by 1934, as the largest aircraft ever built using the Junkers methods of metal aircraft construction.
+In the 1930s, development of the jet engines began in Germany and in Britain and they began testing in 1939 before World War II. The jet engine saw considerable development during the war, with a few jet powered aircraft being used in the war.
+
+After enrolling in the Military Aviation Academy in Eskisehir in 1936 and undertaking training at the First Aircraft Regiment, Sabiha Gökçen, flew fighter and bomber planes becoming the first Turkish, female aviator and the world's first, female, combat pilot. During her flying career, she achieved some 8,000 hours, 32 of which were combat missions.
+
+=== World War II (1939–1945) ===
+
+World War II saw a great increase in the pace of development and production, not only of aircraft but also the associated flight-based weapon delivery systems. Air combat tactics and doctrines started being rapidly developed. Large-scale strategic bombing campaigns were launched, fighter escorts introduced and the more flexible aircraft and weapons allowed precise attacks on small targets with dive bombers, fighter-bombers, and ground-attack aircraft. New technologies like radar also allowed more coordinated and controlled deployment of air defence.
+
+The first jet aircraft to fly was the Heinkel He 178 (Germany), flown by Erich Warsitz in 1939, followed by the world's first operational jet aircraft, the Messerschmitt Me 262, in July 1942 and world's first jet-powered bomber, the Arado Ar 234, in June 1943. British developments, like the Gloster Meteor, followed afterwards, but saw only brief use in World War II. The first cruise missile (V-1), the first ballistic missile (V-2), the first (and to date only) operational rocket-powered combat aircraft Me 163—which attained velocities of up to 1,130 km/h (700 mph) in test flights—and the first vertical take-off a manned point-defence interceptor, the Bachem Ba 349 Natter, were also developed by Germany. However, jet and rocket aircraft had only limited impact due to their late introduction, fuel shortages, the lack of experienced pilots and the declining war industry of Germany.
+Not only aeroplanes, but also helicopters saw rapid development in the Second World War, with the introduction of the Focke Achgelis Fa 223, the Flettner Fl 282 synchropter in 1941 in Germany and the Sikorsky R-4 in 1942 in the USA.
+
+=== Postwar era (1945–1979) ===
+
+Following World War II, commercial aviation expanded quickly, primarily relying on former military aircraft to carry passengers and cargo. There was an excess of large bombers, such as the B-29 and Lancaster, which were easily converted for commercial use. The DC-3 specifically played a key role, enabling longer and more efficient flights.
+
+=== Jet Age (1950–1979) ===

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+
+The British de Havilland Comet became the first commercial jet airliner and was introduced into scheduled service by 1952. The aircraft was a breakthrough in technical achievements, but had several intense failures. The square design of the windows caused stress cracks from metal fatigue, caused by cycles of cabin pressurization and depressurization. This eventually led to severe structural failures in the fuel area. These issues were resolved too late, since competing jet airliners were already flying.
+On 15 September 1956, the USSR's airline Aeroflot became the first to offer continuous, regular jet services using the Tupolev Tu-104. Soon after, Boeing 707 and DC-8 also set new standards in comfort, safety, and passenger experience. This was the beginning of the Jet Age, the introduction of large-scale commercial air travel.
+Jet airliners were able to fly higher, faster, and farther than older piston‑powered propliners, making transcontinental and intercontinental travel considerably faster and easier. Aircraft leaving North America and crossing the Atlantic Ocean (and later, the Pacific Ocean) could now fly to their destinations non-stop, making much of the world accessible within a single day's travel for the first time. Large jetliners could carry more passengers than piston-powered airliners, which caused air fares to decline and opened international travel to a broader range of socioeconomic groups.
+In October 1947, Chuck Yeager became the first to fly faster than the speed of sound when he piloted the rocket-powered Bell X-1 past the sound barrier. The air speed record for an aircraft was set by the X-15 at 4,534 mph (7,297 km/h) or Mach 6.1 in 1967. This record was later broken by the X-43 in 2004, excluding spacecraft.
+Military aircraft had a strategic advantage during the Cold War with the invention of nuclear bombs in 1945. Even just a small fleet of bombers could inflict catastrophic damage, which caused for the development of effective defenses. One early development was supersonic interceptor aircraft. By 1955, the focus shifted toward guided surface-to-air missiles. This eventually led to the emergence of intercontinental ballistic missiles (ICBMs), which have nuclear capabilities. An early example of ICBMs occurred in 1957 when the Soviet Union launched Sputnik 1, beginning the Space Race.
+In 1961, Yuri Gagarin became the first human in space when he completed a single orbit around Earth in 108 minutes aboard Vostok I. Following this, the United States sent Alan Shepard on a suborbital flight using a Mercury program capsule. In 1963, Canada became the third nation to enter space with the launch of its satellite, Alouette I. The space race culminated in the landing on the moon in 1969.
+
+The Harrier jump jet, capable of vertical landing and takeoff, first flew in 1969. This was also the year of the introduction of the Boeing 747. Additionally, the Aérospatiale-BAC Concorde supersonic passenger airliner had its maiden flight. The Boeing 747 was the largest commercial passenger aircraft ever to fly at the time, now replaced by the Airbus A380, capable of transporting 853 passengers. Aeroflot started flying  the Tu-144—the first supersonic passenger plane in 1975. The next year, British Airways and Air France began supersonic flights over the Atlantic.
+In 1979, the Gossamer Albatross achieved the status of the first human-powered aircraft to fly over the English channel, which had been a dream for centuries.
+
+=== Digital age (1980–present) ===
+
+The last quarter of the 20th century saw a change of emphasis.  No longer was revolutionary progress made in flight speeds, distances and materials technology. This part of the century instead saw the spreading of the digital revolution both in flight avionics and in aircraft design and manufacturing techniques.
+In 1986, Dick Rutan and Jeana Yeager flew an aircraft, the Rutan Voyager, around the world un-refuelled, and without landing. In 1999, Bertrand Piccard became the first person to circle the earth in a balloon.
+Digital fly-by-wire systems allow an aircraft to be designed with relaxed static stability. These systems were initially used to increase the manoeuvrability of military aircraft such as the General Dynamics F-16 Fighting Falcon, however they are now being used to reduce drag on commercial airliners.
+The U.S. Centennial of Flight Commission was established in 1999 to encourage the broadest national and international participation in the celebration of 100 years of powered flight. It publicized and encouraged a number of programmes, projects and events intended to educate people about the history of aviation.

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+title: "History of aviation"
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+---
+
+== 21st century ==
+21st-century aviation has seen increasing interest in fuel savings and fuel diversification, as well as low cost airlines and facilities. Additionally, much of the developing world that did not have good access to air transport has been steadily adding aircraft and facilities; though severe congestion remains a problem in many up and coming nations. Around 20,000 city pairs are served by commercial aviation, up from less than 10,000 as recently as 1996.
+There appears to be newfound interest in returning to the supersonic era whereby waning demand in the turn of the 20th century made flights unprofitable, as well as the final commercial stoppage of the Concorde due to reduced demand following a fatal accident and rising costs.
+At the beginning of the 21st century, digital technology allowed subsonic military aviation to begin eliminating the pilot in favour of remotely operated or completely autonomous unmanned aerial vehicles (UAVs). In April 2001, the unmanned aircraft Global Hawk flew from Edwards AFB in the US to Australia non-stop and un-refuelled. This is the longest point-to-point flight ever undertaken by an unmanned aircraft and took 23 hours and 23 minutes. In October 2003, the first totally autonomous flight across the Atlantic by a computer-controlled model aircraft occurred. UAVs are now an established feature of modern warfare, carrying out pinpoint attacks under the control of a remote operator.
+Major disruptions to air travel in the 21st century included the closing of U.S. airspace due to the September 11 attacks, and the closing of most of European airspace after the 2010 eruption of Eyjafjallajökull.
+In 2015, André Borschberg and Bertrand Piccard flew a record distance of 4,481 miles (7,211 km) from Nagoya, Japan to Honolulu, Hawaii in a solar-powered plane, Solar Impulse 2. The flight took nearly five days; during the nights the aircraft used its batteries and the potential energy gained during the day.
+On 14 July 2019, Frenchman Franky Zapata attracted worldwide attention when he participated at the Bastille Day military parade riding his invention, a jet-powered Flyboard Air. He subsequently succeeded in crossing the English Channel on his device on 4 August 2019, covering the 35-kilometre (22 mi) journey from Sangatte in northern France to St Margaret's Bay in Kent, UK, in 22 minutes, with a midpoint fueling stop included.
+24 July 2019 was the busiest day in aviation, Flightradar24 recorded a total of over 225,000 flights that day. It includes helicopters, private jets, gliders, sight-seeing flights, as well as personal aircraft.
+On 10 June 2020, the Pipistrel Velis Electro became the first electric aeroplane to secure a type certificate from EASA.
+In the early 21st Century, the first fifth-generation military fighters were produced, starting with the F-22 Raptor. As of 2019, Russia, America and China have 5th gen aircraft.
+The COVID-19 pandemic had a significant impact on the aviation industry due to the resulting travel restrictions as well as slump in demand among travellers, and may also affect the future of air travel. For example, the mandatory use of face masks on planes was common when flying in 2020 and 2021.
+
+=== Mars ===
+On 19 April 2021, NASA successfully flew its diminutive unmanned helicopter Ingenuity on Mars, humanity's first controlled powered aircraft flight on another planet. The helicopter rose to a height of three metres and hovered in a stable holding position for 30 seconds. A video of the flight was made by its accompanying rover, Perseverance.
+Ingenuity, which was initially designed for five demonstration flights, flew 72 times traveling 11 miles in nearly three years. As a homage to all of its aerial predecessors, it carries a postage stamp sized piece of wing fabric from the 1903 Wright Flyer.
+Ingenuity's last flight was 18 January 2024, a span of 2 years, 333 days since its first takeoff (the duration in Martian days, or sols, was 1035). Broken and damaged rotor blades suffered during its final landing forced the helicopter's retirement.
+
+== See also ==
+
+Aviation archaeology
+Claims to the first powered flight
+List of firsts in aviation
+Timeline of aviation
+
+== References ==
+
+=== Bibliography ===
+
+== Further reading ==
+
+Van Vleck, Jenifer (2013). Empire of the Air: Aviation and the American Ascendancy. Cambridge, MA: Harvard University Press.
+
+== External links ==
+
+E. C. Vivian (October 1920). History of Aeronautics.
+"The Gaston and Albert Tissandier Collection". Rare Book & Special Collections. Library of Congress. Publications relating to the history of aeronautics, (1,800 titles dispersed in the collection)
+Carroll F. Gray. "Flying Machines".
+Peter Whalley. "History of Flight - Key events". Knowledge Media Institute. Open University.
+"Historical archive since 1919". Aerospace Industries Association.
+"Alberto Santos-Dumont Est Peut-Être Le Véritable 'Père De L'aviation'". Magazine Aviation. (in French)
+
+=== Articles ===
+Carroll F. Gray (August 2002). "The five first flights". WW1 AERO - The Journal of the Early Aeroplane. Archived from the original on 22 April 2018. Retrieved 13 June 2003.
+Jürgen Schmidhuber (2003). "First Powered Flight - Plane Truth". Nature. No. 421. p. 689.
+Richard Harris (December 2003). "First Flyers—They're not who you think..." In Flight USA. Archived from the original on 13 July 2011. Retrieved 26 December 2007.
+Richard P. Hallion (July 2008). "Airplanes that Transformed Aviation". Air & Space Magazine. Smithsonian.
+"American Aviation Heritage" (PDF). National Park Service. March 2011. Archived from the original (PDF) on 7 February 2016.
+
+=== Media ===
+"Transportation Photographs - Airplanes". Digital Collections. University of Washington Libraries. in the Pacific Northwest region and Western United States during the first half of the 20th century.
+"Strut design airplanes". University of Houston Digital Library. 1911.
+Michael Maloney (2009). A Dream of Flight (Documentary on the first powered flight by a Briton in Britain, JTC Moore Brabazon, in 1909). Countrywide Productions.

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+title: "History of aviation"
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+
+On 4 June, a crowd gathered in Annonay, France, to witness the unmanned hot air balloon display by the Montgolfier brothers. Their 500-pound balloon ascended to nearly 3,000 feet and traveled over a mile and a half. It stayed in the air for ten minutes before tipping over and catching fire.
+On 27 August, Jacques Charles and the Robert brothers unveiled the first unmanned hydrogen balloon from Paris' Champ de Mars. It landed almost an hour later in Gonesse, where terrified farmers mistook it for a monster and destroyed it.
+On 19 October, in front of 2,000 spectators, Jean-François Pilâtre de Rozier and the Marquis d'Arlandes boarded the Montgolfier aircraft as the first people. Later that day, Giroud de Villette, another pilot, took to the skies much higher.
+On 21 November, the Montgolfiers launched the first free flight with human passengers. King Louis XVI had originally decreed that condemned criminals would be the first pilots, but Jean-François Pilâtre de Rozier, along with the Marquis François d'Arlandes, successfully petitioned for the honour. They drifted 8 km (5.0 mi) in a balloon powered by a wood fire.
+On 1 December, Jacques Charles and the Nicolas-Louis Robert launched their manned hydrogen balloon from the Jardin des Tuileries in Paris, as a crowd of 400,000 witnessed. They ascended to a height of about 1,800 feet (550 m)[15] and landed at sunset in Nesles-la-Vallée after a flight of 2 hours and 5 minutes, covering 36 km. After Robert alighted, Charles decided to ascend alone. This time he ascended rapidly to an altitude of about 9,800 feet (3,000 m), where he saw the sun again, suffered extreme pain in his ears, and never flew again.
+Ballooning became a major interest in Europe in the late 18th century, providing the first detailed understanding of the relationship between altitude and the atmosphere.
+Non-steerable balloons were employed during the American Civil War by the Union Army Balloon Corps. The young Ferdinand von Zeppelin first flew as a balloon passenger with the Union Army of the Potomac in 1863.
+In the early 1900s, ballooning was a popular sport in Britain. These privately owned balloons usually used coal gas as the lifting gas. This has half the lifting power of hydrogen so the balloons had to be larger, however, coal gas was far more readily available and the local gas works sometimes provided a special lightweight formula for ballooning events.
+
+=== Airships ===
+
+Airships were originally called "dirigible balloons" and are still sometimes called dirigibles today.
+Work on developing a steerable (or dirigible) balloon continued sporadically throughout the 19th century. The first powered, controlled, sustained lighter-than-air flight is believed to have taken place in 1852 when Henri Giffard flew 15 miles (24 km) in France, with a steam engine-driven craft.
+Another advancement was made in 1884, when the first fully controllable free-flight was made in a French Army electric-powered airship, La France, by Charles Renard and Arthur Krebs. The 170-foot (52 m) long, 66,000-cubic-foot (1,900 m3) airship covered 8 km (5.0 mi) in 23 minutes with the aid of an 8½ horsepower electric motor.
+However, these aircraft were generally short-lived and extremely frail. Routine, controlled flights did not occur until the advent of the internal combustion engine.
+
+The first aircraft to make routine controlled flights were non-rigid airships (sometimes called "blimps".) The most successful early pioneering pilot of this type of aircraft was the Brazilian Alberto Santos-Dumont who effectively combined a balloon with an internal combustion engine. On 19 October 1901, he flew his airship Number 6 over Paris from the Parc de Saint Cloud around the Eiffel Tower and back in under 30 minutes to win the Deutsch de la Meurthe prize. Santos-Dumont went on to design and build several aircraft. The subsequent controversy surrounding his and others' competing claims with regard to aircraft overshadowed his great contribution to the development of airships.
+At the same time that non-rigid airships were starting to have some success, the first successful rigid airships were also being developed. These were far more capable than fixed-wing aircraft in terms of pure cargo-carrying capacity for decades. Rigid airship design and advancement was pioneered by the German count Ferdinand von Zeppelin.
+Construction of the first Zeppelin airship began in 1899 in a floating assembly hall on Lake Constance in the Bay of Manzell, Friedrichshafen. This was intended to ease the starting procedure, as the hall could easily be aligned with the wind. The prototype airship LZ 1 (LZ for "Luftschiff Zeppelin") had a length of 128 m (420 ft), was driven by two 10.6 kW (14.2 hp) Daimler engines and balanced by moving a weight between its two nacelles.
+Its first flight, on 2 July 1900, lasted for only 18 minutes, as LZ 1 was forced to land on the lake after the winding mechanism for the balancing weight had broken. Upon repair, the technology proved its potential in subsequent flights, bettering the 6 m/s speed attained by the French airship La France by 3 m/s, but could not yet convince possible investors. It was several years before the Count was able to raise enough funds for another try.
+The German airship passenger service known as DELAG (Deutsche-Luftschiffahrts AG) was established in 1910.
+Although airships were used in both World War I and II, and continue on a limited basis to this day, their development has been largely overshadowed by heavier-than-air craft.
+
+== Heavier than air ==

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+title: "History of aviation"
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+category: "reference"
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+---
+
+=== 17th and 18th centuries ===
+Traveller Evliya Çelebi reported that in 1633, Ottoman scientist and engineer Lagari Hasan Çelebi blasted off from Sarayburnu in a 7-winged rocket propelled by 50 okka (140 lbs) of gunpowder. The flight was said to have been undertaken at the time of the birth of Sultan Murad IV's daughter. As Evliya Celebi wrote, Lagari proclaimed before launching his craft "O my sultan! Be blessed, I am going to talk to Jesus!"; after ascending in the rocket, he landed in the sea, swimming ashore and joking "O my sultan! Jesus sends his regards to you!"; he was rewarded by the Sultan with silver and the rank of sipahi in the Ottoman army. Evliya Çelebi also wrote of Lagari's brother, Hezârfen Ahmed Çelebi, making a flight by glider a year earlier.
+Italian inventor Tito Livio Burattini, invited by the Polish King Władysław IV to his court in Warsaw, built a model aircraft with four fixed glider wings in 1647.  Described as "four pairs of wings attached to an elaborate 'dragon'", it was said to have successfully lifted a cat in 1648 but not Burattini himself. He promised that "only the most minor injuries" would result from landing the craft. His "Dragon Volant" is considered "the most elaborate and sophisticated aeroplane to be built before the 19th Century".
+The first published paper on aviation was "Sketch of a Machine for Flying in the Air" by Emanuel Swedenborg published in 1716. This flying machine consisted of a light frame covered with strong canvas and provided with two large oars or wings moving on a horizontal axis, arranged so that the upstroke met with no resistance while the downstroke provided lifting power. Swedenborg knew that the machine would not fly, but suggested it as a start and was confident that the problem would be solved. Swedenborg proved prescient in his observation that a method of powering of an aircraft was one of the critical problems to be overcome.
+
+It seems easier to talk of such a machine than to put it into actuality, for it requires greater force and less weight than exists in a human body. The science of mechanics might perhaps suggest a means, namely, a strong spiral spring. If these advantages and requisites are observed, perhaps in time to come someone might know how better to utilise our sketch and cause some addition to be made so as to accomplish that which we can only suggest. Yet there are sufficient proofs and examples from nature that such flights can take place without danger, although when the first trials are made you may have to pay for the experience, and not mind an arm or leg.
+On 16 May 1793, Spanish inventor Diego Marín Aguilera crossed the river Arandilla in Coruña del Conde, Castile, flying 300 to 400 metres (980 to 1,310 ft) with a flying machine.
+
+=== 19th century ===
+Balloon jumping replaced tower jumping, also demonstrating with typically fatal results that man-power and flapping wings were useless in achieving flight. At the same time scientific study of heavier-than-air flight began in earnest. In 1801, the French officer André Guillaume Resnier de Goué managed a 300-metre glide by starting from the top of the city walls of Angoulême and he broke one leg on arrival. In 1837, French mathematician and brigadier general Isidore Didion stated, "Aviation will be successful only if one finds an engine whose ratio with the weight of the device to be supported will be larger than current steam machines or the strength developed by humans or most of the animals".
+
+==== George Cayley and the first modern aircraft ====
+George Cayley was first called the "father of the aeroplane" in 1846. During the last years of the 18th century, he had begun the first rigorous study of the physics of flight and would later design the first modern heavier-than-air craft. Among his many achievements, his most important contributions to aeronautics include:

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+
+Clarifying our ideas and laying down the principles of heavier-than-air flight.
+Reaching a scientific understanding of the principles of bird flight.
+Scientific aerodynamic experiments were conducted to demonstrate drag and streamlining, movement of the center of pressure, and the increase in lift from curving the wing surface.
+Defining the modern aeroplane configuration comprising a fixed-wing, fuselage and tail assembly.
+Demonstrations of manned, gliding flight.
+Identified the crucial understanding that a lightweight, powerful engine would be necessary for sustained heavier-than-air flight, now known as the power-to-weight ratio
+Recognized for establishing the theoretical foundation for engine use in airplanes and modern aircraft design by identifying and explaining the four fundamental forces of flight: lift, thrust, drag, and weight.
+Cayley's research on the aeroplane aimed to address the four fundamental areas that are essential to aeronautics: propulsion, structural design, aerodynamics, and stability and control. His work laid the groundwork for a comprehensive understanding of these critical components, which continue to be vital in the field today.
+Cayley's first innovation was to study the basic science of lift by adopting the whirling arm test rig for use in aircraft research and using simple aerodynamic models on the arm, rather than attempting to fly a model of a complete design.
+In 1799, he set down the concept of the modern aeroplane as a fixed-wing flying machine with separate systems for lift, propulsion, and control.
+In 1804, Cayley constructed a model glider, which was the first modern heavier-than-air flying machine. It had the layout of a conventional modern aircraft, with an inclined wing towards the front and an adjustable tail at the back with both tailplane and fin. A movable weight allowed adjustment of the model's centre of gravity.
+In 1809, goaded by the farcical antics of his contemporaries, he began the publication of a landmark three-part treatise titled "On Aerial Navigation" (1809–1810). In it he wrote the first scientific statement of the problem, "The whole problem is confined within these limits, viz. to make a surface support a given weight by the application of power to the resistance of air". He identified the four vector forces that influence an aircraft: thrust, lift, drag and weight and distinguished stability and control in his designs. He also identified and described the importance of the cambered aerofoil, dihedral, diagonal bracing and drag reduction, and contributed to the understanding and design of ornithopters and parachutes.
+In 1848, he had progressed far enough to construct a glider in the form of a triplane large and safe enough to carry a child. A local boy was chosen; his name is unknown.
+He went on to publish in 1852 the design for a full-size manned glider or "governable parachute" to be launched from a balloon. He then constructed a version capable of launching from the top of a hill, which carried the first adult aviator across Brompton Dale in 1853.
+
+==== Age of steam ====
+
+Drawing directly from Cayley's work, Henson's 1842 design for an aerial steam carriage broke new ground. Although only a design, it was the first in history for a propeller-driven fixed-wing aircraft.
+
+1866 saw the founding of the Aeronautical Society of Great Britain and two years later the world's first aeronautical exhibition was held at the Crystal Palace, London, where John Stringfellow was awarded a £100 prize for the steam engine with the best power-to-weight ratio. In 1848, Stringfellow achieved the first powered flight using an unmanned 10 feet (3.0 m) wingspan steam-powered monoplane built in a disused lace factory in Chard, Somerset. Employing two contra-rotating propellers on the first attempt, made indoors, the machine flew ten feet before becoming destabilised, damaging the craft. The second attempt was more successful, the machine leaving a guidewire to fly freely, achieving thirty yards of straight and level powered flight. Francis Herbert Wenham presented the first paper to the newly formed Aeronautical Society (later the Royal Aeronautical Society), On Aerial Locomotion. He advanced Cayley's work on cambered wings, making important findings. To test his ideas, from 1858 he had constructed several gliders, both manned and unmanned, and with up to five stacked wings. He realised that long, thin wings are better than bat-like ones because they have more leading edge for their area. Today this relationship is known as the aspect ratio of a wing.
+The latter part of the 19th century became a period of intense study, characterized by the "gentleman scientists" who represented most research efforts until the 20th century. Among them was the British scientist-philosopher and inventor Matthew Piers Watt Boulton, who studied lateral flight control and was the first to patent an aileron control system in 1868.
+In 1871, Wenham made the first wind tunnel using a fan, driven by a steam engine, to propel air down a 12 ft (3.7 m) tube to the model.
+
+Meanwhile, the British advances had galvanised French researchers. In 1857, Félix du Temple proposed a monoplane with a tailplane and retractable undercarriage. Developing his ideas with a model powered first by clockwork and later by steam, he eventually achieved a short hop with a full-size manned craft in 1874. It achieved lift-off under its own power after launching from a ramp, glided for a short time and returned safely to the ground, making it the first successful powered glide in history.
+In 1865, Louis Pierre Mouillard published an influential book The Empire Of The Air (l'Empire de l'Air).
+
+In 1856, Frenchman Jean-Marie Le Bris made the first flight higher than his point of departure, by having his glider "L'Albatros artificiel" pulled by a horse on a beach. He reportedly achieved a height of 100 metres, over a distance of 200 metres.

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+
+Alphonse Pénaud, a Frenchman, advanced the theory of wing contours and aerodynamics. He also constructed successful models of aeroplanes, helicopters and ornithopters. In 1871 he flew the first aerodynamically stable fixed-wing aeroplane, a model monoplane he called the "Planophore", a distance of 40 m (130 ft). Pénaud's model incorporated several of Cayley's discoveries, including the use of a tail, wing dihedral for inherent stability, and rubber power. The planophore also had longitudinal stability, being trimmed such that the tailplane was set at a smaller angle of incidence than the wings, an original and important contribution to the theory of aeronautics. Pénaud's later project for an amphibian aeroplane, although never built, incorporated other modern features. A tailless monoplane with a single vertical fin and twin tractor propellers, it also featured hinged rear elevator and rudder surfaces, retractable undercarriage and a fully enclosed, instrumented cockpit.
+
+Another theorist was Frenchman Victor Tatin. In 1879, he flew a model which, like Pénaud's project, was a monoplane with twin tractor propellers but also had a separate horizontal tail. It was powered by compressed air. Flown tethered to a pole, this was the first model to take off under its own power.
+In 1884, Alexandre Goupil published his work La Locomotion Aérienne (Aerial Locomotion), although the flying machine he later constructed failed to fly.
+
+In 1890, the French engineer Clément Ader completed the first of three steam-driven flying machines, the Éole. On 9 October 1890, Ader made an uncontrolled hop of around 50 metres (160 ft); this was the first manned aeroplane to take off under its own power. His Avion III of 1897, notable only for having twin steam engines, failed to fly: Ader later claimed success and was not debunked until 1910 when the French Army published its report on his attempt.
+
+Hiram Maxim was an American engineer who had moved to England. He built his own whirling arm rig and wind tunnel and constructed a large machine with a wingspan of 105 feet (32 m), a length of 145 feet (44 m), fore and aft horizontal surfaces and a crew of three. Twin propellers were powered by two lightweight compound steam engines each delivering 180 hp (130 kW). The overall weight was 8,000 pounds (3,600 kg). It was intended as a test rig to investigate aerodynamic lift; because it lacked flight controls it ran on rails, with a second set of rails above the wheels to restrain it. Completed in 1894, on its third run it broke from the rail, became airborne for about 200 yards at two to three feet of altitude and was badly damaged upon falling back to the ground. It was subsequently repaired, but Maxim abandoned his experiments shortly afterwards.
+
+=== Manned gliders and Otto Lilienthal ===
+
+Around the last decade of the 19th century, a number of key figures were refining and defining the modern aeroplane. Lacking a suitable engine, aircraft work focused on stability and control in gliding flight. In 1879, Biot constructed a bird-like glider with the help of Massia and flew in it briefly. It is preserved in the Musee de l'Air, France, and is claimed to be the earliest man-carrying flying machine still in existence.
+The Englishman Horatio Phillips made key contributions to aerodynamics. He conducted extensive wind tunnel research on aerofoil sections, proving the principles of aerodynamic lift foreseen by Cayley and Wenham. His findings underpin all modern aerofoil design. Between 1883 and 1886, the American John Joseph Montgomery developed a series of three manned gliders, before conducting his own independent investigations into aerodynamics and circulation of lift.

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+
+Otto Lilienthal became known as the "Glider King" or "Flying Man" of Germany. He duplicated Wenham's work and greatly expanded on it in 1884, publishing his research in 1889 as Birdflight as the Basis of Aviation (Der Vogelflug als Grundlage der Fliegekunst), which is seen as one of the most important works in aviation history. He also produced a series of hang gliders, including bat-wing, monoplane, and biplane forms, such as the Derwitzer Glider and Normal soaring apparatus, which is considered to be the first airplane in series production, making the "Maschinenfabrik Otto Lilienthal" the first airplane production company in the world.
+Starting in 1891, he became the first person to make controlled untethered glides routinely, and the first to be photographed flying a heavier-than-air machine, stimulating interest around the world. Lilienthal's work led to him developing the concept of the modern wing. His flights in the year 1891 are seen as the beginning of human flight and because of that he is often referred to as either the "father of aviation" or "father of flight".
+He rigorously documented his work, including photographs, and for this reason is one of the best known of the early pioneers. Lilienthal made over 2,000 glider flights until his death in 1896 from injuries sustained in a glider crash.
+Picking up where Lilienthal left off, Octave Chanute took up aircraft design after an early retirement, and funded the development of several gliders. In the summer of 1896, his team flew several of their designs eventually deciding that the best was a biplane design. Like Lilienthal, he documented and photographed his work.
+In Britain Percy Pilcher, who had worked for Maxim, built and successfully flew several gliders during the mid to late 1890s.
+The invention of the box kite during this period by the Australian Lawrence Hargrave led to the development of the practical biplane. In 1894, Hargrave linked four of his kites together, added a sling seat, and was the first to obtain lift with a heavier than air aircraft, when he flew up 16 feet (4.9 m). Later pioneers of manned kite flying included Samuel Franklin Cody in England and Captain Génie Saconney in France.
+William Frost from Pembrokeshire, Wales started his project in 1880 and after 16 years, he designed a flying machine and in 1894 won a patent for a "Frost Aircraft Glider". Reports say witnesses claimed the craft flew at Saundersfoot in 1896, travelling 500 yards before colliding with a tree and falling in a field.
+
+=== Langley ===
+
+After a distinguished career in astronomy and shortly before becoming Secretary of the Smithsonian Institution, Samuel Pierpont Langley started a serious investigation into aerodynamics at what is today the University of Pittsburgh. In 1891, he published Experiments in Aerodynamics detailing his research, and then turned to building his designs. He hoped to achieve automatic aerodynamic stability, so he gave little consideration to in-flight control. On 6 May 1896, Langley's Aerodrome No. 5 made the first successful sustained flight of an unpiloted, engine-driven heavier-than-air craft of substantial size. It was launched from a spring-actuated catapult mounted on top of a houseboat on the Potomac River near Quantico, Virginia. Two flights were made that afternoon, one of 1,005 metres (3,297 ft) and a second of 700 metres (2,300 ft), at a speed of approximately 25 miles per hour (40 km/h). On both occasions, the Aerodrome No. 5 landed in the water as planned, because, in order to save weight, it was not equipped with landing gear. On 28 November 1896, another successful flight was made with the Aerodrome No. 6. This flight, of 1,460 metres (4,790 ft), was witnessed and photographed by Alexander Graham Bell. The Aerodrome No. 6 was actually Aerodrome No. 4 greatly modified. So little remained of the original aircraft that it was given a new designation.
+With the successes of the Aerodrome No. 5 and No. 6, Langley started looking for funding to build a full-scale man-carrying version of his designs. Spurred by the Spanish–American War, the U.S. government granted him $50,000 to develop a man-carrying flying machine for aerial reconnaissance. Langley planned on building a scaled-up version known as the Aerodrome A, and started with the smaller Quarter-scale Aerodrome, which flew twice on 18 June 1901, and then again with a newer and more powerful engine in 1903.
+With the basic design apparently successfully tested, he then turned to the problem of a suitable engine. He contracted Stephen Balzer to build one, but was disappointed when it delivered only 8 hp (6.0 kW) instead of the 12 hp (8.9 kW) he expected. Langley's assistant, Charles M. Manly, then reworked the design into a five-cylinder water-cooled radial that delivered 52 hp (39 kW) at 950 rpm, a feat that took years to duplicate. Now with both power and a design, Langley put the two together with great hopes.
+To his dismay, the resulting aircraft proved to be too fragile. Simply scaling up the original small models resulted in a design that was too weak to hold itself together. Two launches in late 1903 both ended with the Aerodrome immediately crashing into the water. The pilot, Manly, was rescued each time. Also, the aircraft's control system was inadequate to allow quick pilot responses, and it had no method of lateral control, and the Aerodrome's aerial stability was marginal.
+Langley's attempts to gain further funding failed, and his efforts ended. Nine days after his second abortive launch on 8 December, the Wright brothers successfully flew their Flyer. Glenn Curtiss made 93 modifications to the Aerodrome and flew this very different aircraft in 1914. Without acknowledging the modifications, the Smithsonian Institution asserted that Langley's Aerodrome was the first machine "capable of flight".
+
+=== Whitehead ===

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+
+Gustave Weißkopf was a German who emigrated to the U.S., where he soon changed his name to Whitehead. From 1897 to 1915, he designed and built early flying machines and engines. On 14 August 1901, two and a half years before the Wright Brothers' flight, he claimed to have carried out a controlled, powered flight in his Number 21 monoplane at Fairfield, Connecticut. The flight was reported in the Bridgeport Sunday Herald local newspaper. About 30 years later, several people questioned by a researcher claimed to have seen that or other Whitehead flights.
+In March 2013, Jane's All the World's Aircraft, an authoritative source for contemporary aviation, published an editorial which accepted Whitehead's flight as the first manned, powered, controlled flight of a heavier-than-air craft. The Smithsonian Institution (custodians of the original Wright Flyer) and many aviation historians continue to maintain that Whitehead did not fly as suggested. The historians of the Royal Aeronautical Society noted that: "All available evidence fails to support the claim that Gustave Whitehead made sustained, powered, controlled flights predating those of the Wright brothers." The editors of Scientific American agree: "The data show that not only was Whitehead not first in flight, but that he may never have made a controlled, powered flight at any time."
+
+=== Pearse ===
+
+Richard Pearse was a New Zealand farmer and inventor who performed pioneering aviation experiments. Witnesses interviewed many years afterward claimed that Pearse flew and landed a powered heavier-than-air machine on 31 March 1903, nine months before the Wright brothers flew.  Documentary evidence for these claims remains open to interpretation and dispute, and Pearse himself never made such claims. In a newspaper interview in 1909, he said he did not "attempt anything practical ... until 1904". If he did fly in 1903, the flight appears to have been poorly controlled in comparison to the Wrights'.
+
+=== Wright brothers ===
+
+Using a methodical approach and concentrating on the controllability of the aircraft, the brothers built and tested a series of kite and glider designs from 1898 to 1902 before attempting to build a powered design. The gliders worked, but not as well as the Wrights had expected based on the experiments and writings of their predecessors. Their first full-size glider, launched in 1900, had only about half the lift they anticipated. Their second glider, built the following year, performed even more poorly. Rather than giving up, the Wrights constructed their own wind tunnel and created a number of sophisticated devices to measure lift and drag on the 200 wing designs they tested. As a result, the Wrights corrected earlier mistakes in calculations regarding drag and lift. Their testing and calculating produced a third glider with a higher aspect ratio and true three-axis control. They flew it successfully hundreds of times in 1902, and it performed far better than the previous models. By using a rigorous system of experimentation, involving wind-tunnel testing of airfoils and flight testing of full-size prototypes, the Wrights not only built a working aircraft the following year, the Wright Flyer, but also helped advance the science of aeronautical engineering.

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+title: "History of aviation"
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+The Wrights appear to be the first to make serious studied attempts to simultaneously solve the power and control problems. Both problems proved difficult, but they never lost interest. They solved the control problem by inventing wing warping for roll control, combined with simultaneous yaw control with a steerable rear rudder. Almost as an afterthought, they designed and built a low-powered internal combustion engine. They also designed and carved wooden propellers that were more efficient than any before, enabling them to gain adequate performance from their low engine power. Although wing-warping as a means of lateral control was used only briefly during the early history of aviation, the principle of combining lateral control in combination with a rudder was a key advance in aircraft control. While many aviation pioneers appeared to leave safety largely to chance, the Wrights' design was greatly influenced by the need to teach themselves to fly without unreasonable risk to life and limb, by surviving crashes. This emphasis, as well as low engine power, was the reason for low flying speed and for taking off in a headwind. Performance, rather than safety, was the reason for the rear-heavy design because the canard could not be highly loaded; anhedral wings were less affected by crosswinds and were consistent with the low yaw stability.
+According to the Smithsonian Institution and Fédération Aéronautique Internationale (FAI), the Wrights made the first sustained, controlled, powered heavier-than-air manned flight at Kill Devil Hills, North Carolina, four miles (8 km) south of Kitty Hawk, North Carolina on 17 December 1903.
+The first flight by Orville Wright, of 120 feet (37 m) in 12 seconds, was recorded in a famous photograph. In the fourth flight of the same day, Wilbur Wright flew 852 feet (260 m) in 59 seconds. The flights were witnessed by three coastal lifesaving crewmen, a local businessman, and a boy from the village, making these the first public flights and the first well-documented ones.
+Orville described the final flight of the day: "The first few hundred feet were up and down, as before, but by the time three hundred feet had been covered, the machine was under much better control. The course for the next four or five hundred feet had but little undulation. However, when out about eight hundred feet the machine began pitching again, and, in one of its darts downward, struck the ground. The distance over the ground was measured to be 852 feet (260 m); the time of the flight was 59 seconds. The frame supporting the front rudder was badly broken, but the main part of the machine was not injured at all. We estimated that the machine could be put in condition for flight again in about a day or two". They flew only about ten feet above the ground as a safety precaution, so they had little room to manoeuvre, and all four flights in the gusty winds ended in a bumpy and unintended "landing". Modern analysis by Professor Fred E. C. Culick and Henry R. Rex (1985) has demonstrated that the 1903 Wright Flyer was so unstable as to be almost unmanageable by anyone but the Wrights, who had trained themselves in the 1902 glider.
+The Wrights continued flying at Huffman Prairie near Dayton, Ohio in 1904–1905. In May 1904, they introduced the Flyer II, a heavier and improved version of the original Flyer. On 23 June 1905, they first flew a third machine, the Flyer III. After a severe crash on 14 July 1905, they rebuilt the Flyer III and made important design changes. They almost doubled the size of the elevator and rudder and moved them about twice the distance from the wings. They added two fixed vertical vanes (called "blinkers") between the elevators and gave the wings a very slight dihedral. They disconnected the rudder from the wing-warping control, and as in all future aircraft, placed it on a separate control handle. When flights resumed the results were immediate. The serious pitch instability that hampered Flyers I and II was significantly reduced, so repeated minor crashes were eliminated. Flights with the redesigned Flyer III started lasting over 10 minutes, then 20, then 30. Flyer III became the first practical aircraft (though without wheels and needing a launching device), flying consistently under full control and bringing its pilot back to the starting point safely and landing without damage. On 5 October 1905, Wilbur flew 24 miles (39 km) in 39 minutes 23 seconds.
+According to the April 1907 issue of the Scientific American magazine, the Wright brothers seemed to have the most advanced knowledge of heavier-than-air navigation at the time. However, the same magazine issue also claimed that no public flight had been made in the United States before its April 1907 issue. Hence, they devised the Scientific American Aeronautic Trophy in order to encourage the development of a heavier-than-air flying machine. Glenn H. Curtiss won the trophy in 1908 with the first pre-announced and officially recorded flight of the June Bug.
+
+== History ==
+
+=== Pioneer Era (1903–1914) ===
+
+This period saw the development of practical aeroplanes and airships and their early application, alongside balloons and kites, for private, sport and military use.
+
+==== Pioneers in Europe ====

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+
+Although the full details of the Wright Brothers' system of flight control had been published in l'Aerophile in January 1906, the importance of this advance was not recognised, and European experimenters generally concentrated on attempting to produce inherently stable machines.
+Short powered flights were performed in France by Romanian engineer Traian Vuia on 18 March and 19 August 1906 when he flew 12 and 24 metres, respectively, in a self-designed, fully self-propelled, fixed-wing aircraft, that possessed a fully wheeled undercarriage. He was followed by Jacob Ellehammer who built a monoplane which he tested with a tether in Denmark on 12 September 1906, flying 42 metres.
+On 13 September 1906, the Brazilian Alberto Santos-Dumont made a public flight in Paris with the 14-bis, also known as Oiseau de proie (French for "bird of prey"). This was canard configured with a pronounced wing dihedral, and covered a distance of 60 m (200 ft) on the grounds of the Chateau de Bagatelle in Paris' Bois de Boulogne before a large crowd of witnesses. This well-documented event was the first flight verified by the Aéro-Club de France of a powered heavier-than-air machine in Europe and won the Deutsch-Archdeacon Prize for the first officially observed flight greater than 25 m (82 ft). On 12 November 1906, Santos-Dumont set the first world record recognized by the Federation Aeronautique Internationale by flying 220 m (720 ft) in 21.5 seconds. Only one more brief flight was made by the 14-bis in March 1907, after which it was abandoned.
+In March 1907, Gabriel Voisin flew the first example of his Voisin biplane. On 13 January 1908, a second example was flown by Henri Farman to win the Deutsch-Archdeacon Grand Prix d'Aviation prize for a flight in which the aircraft flew a distance of more than a kilometre and landed at the point where it had taken off. The flight lasted 1 minute and 28 seconds.
+
+==== Flight as an established technology ====
+
+Santos-Dumont later added ailerons between the wings in an effort to gain more lateral stability. His final design, first flown in 1907, was the series of Demoiselle monoplanes (Nos. 19 to 22). The Demoiselle No 19 could be constructed in only 15 days and became the world's first series production aircraft. The Demoiselle achieved 120 km/h. The fuselage consisted of three specially reinforced bamboo booms. The pilot sat in a seat between the main wheels of a conventional landing gear whose pair of wire-spoked mainwheels were located at the lower front of the airframe, with a tailskid half-way back beneath the rear fuselage structure. The Demoiselle was controlled in flight by a cruciform tail unit hinged on a form of universal joint at the aft end of the fuselage structure to function as elevator and rudder, with roll control provided through wing warping (No. 20), with the wings only warping "down".
+In 1908, Wilbur Wright travelled to Europe, and starting in August gave a series of flight demonstrations at Le Mans in France. The first demonstration, made on 8 August, attracted an audience including most of the major French aviation experimenters, who were astonished by the clear superiority of the Wright Brothers' aircraft, particularly its ability to make tight controlled turns. The importance of using roll control in making turns was recognised by almost all the European experimenters: Henri Farman fitted ailerons to his Voisin biplane and shortly afterwards set up his own aircraft construction business, whose first product was the influential Farman III biplane.
+The following year saw the widespread recognition of powered flight as something other than the preserve of dreamers and eccentrics. On 25 July 1909, Louis Blériot won worldwide fame by winning a £1,000 prize offered by the British Daily Mail newspaper for a flight across the English Channel, and in August around half a million people, including the President of France Armand Fallières and the Prime Minister of the United Kingdom David Lloyd George, attended one of the first aviation meetings, the Grande Semaine d'Aviation at Reims.
+In 1914, pioneering aviator Tony Jannus captained the inaugural flight of the St. Petersburg-Tampa Airboat Line, the world's first commercial passenger airline.
+On 30 July 1914, Tryggve Gran made the first  flight across the Northsea from Cruden Bay in Scotland to Reve in Norway in a Blériot XI in 4 hours and 10 mimutes, a distance of 465 km.
+Historians disagree about whether the Wright brothers patent war impeded development of the aviation industry in the United States compared to Europe. The patent war ended during World War I when the government pressured the industry into forming a patent pool, and major litigants had left the industry.
+
+==== Rotorcraft ====
+
+In 1877, the Italian engineer, inventor and aeronautical pioneer Enrico Forlanini developed an unmanned helicopter powered by a steam engine. It rose to a height of 13 metres (43 feet), where it remained for 20 seconds, after a vertical take-off from a park in Milan. Milan has dedicated its city airport to Enrico Forlanini, the airport is also named Linate Airport, as well as the nearby park, the Parco Forlanini. In Milan he also has an avenue named after him, Viale Enrico Forlanini.
+The first time a manned helicopter is known to have risen off the ground was on a tethered flight in 1907 by the Breguet-Richet Gyroplane. Later the same year the Cornu helicopter, also French, made the first rotary-winged free flight at Lisieux, France. However, these were not practical designs.
+
+==== Military use ====

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+---
+title: "History of biochemistry"
+chunk: 1/3
+source: "https://en.wikipedia.org/wiki/History_of_biochemistry"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:19.261593+00:00"
+instance: "kb-cron"
+---
+
+The history of biochemistry can be said to have started with the ancient Greeks who were interested in the composition and processes of life, although biochemistry as a specific scientific discipline has its beginning around the early 19th century. Some argued that the beginning of biochemistry may have been the discovery of the first enzyme, diastase (today called amylase), in 1833 by Anselme Payen, while others considered Eduard Buchner's first demonstration of a complex biochemical process alcoholic fermentation in cell-free extracts to be the birth of biochemistry. Some might also point to the influential work of Justus von Liebig from 1842, Animal chemistry, or, Organic chemistry in its applications to physiology and pathology, which presented a chemical theory of metabolism, or even earlier to the 18th century studies on fermentation and respiration by Antoine Lavoisier.
+The term biochemistry itself is derived from the combining form bio-, meaning 'life', and chemistry. The word is first recorded in English in 1848, while in 1877, Felix Hoppe-Seyler used the term (Biochemie in German) in the foreword to the first issue of Zeitschrift für Physiologische Chemie (Journal of Physiological Chemistry) as a synonym for physiological chemistry and argued for the setting up of institutes dedicate to its studies. Nevertheless, several sources cite German chemist Carl Neuberg as having coined the term for the new discipline in 1903, and some credit it to Franz Hofmeister.
+The subject of study in biochemistry is the chemical processes in living organisms, and its history involves the discovery and understanding of the complex components of life and the elucidation of pathways of biochemical processes.  Much of biochemistry deals with the structures and functions of cellular components such as proteins, carbohydrates, lipids, nucleic acids and other biomolecules; their metabolic pathways and flow of chemical energy through metabolism; how biological molecules give rise to the processes that occur within living cells; it also focuses on the biochemical processes involved in the control of information flow through biochemical signalling, and how they relate to the functioning of whole organisms. Over the last 40 years the field has had success in explaining living processes such that now almost all areas of the life sciences from botany to medicine are engaged in biochemical research.
+Among the vast number of different biomolecules, many are complex and large molecules (called polymers), which are composed of similar repeating subunits (called monomers). Each class of polymeric biomolecule has a different set of subunit types. For example, a protein is a polymer whose subunits are selected from a set of twenty or more amino acids, carbohydrates are formed from sugars known as monosaccharides, oligosaccharides, and polysaccharides, lipids are formed from fatty acids and glycerols, and nucleic acids are formed from nucleotides. Biochemistry studies the chemical properties of important biological molecules, like proteins, and in particular the chemistry of enzyme-catalyzed reactions. The biochemistry of cell metabolism and the endocrine system has been extensively described. Other areas of biochemistry include the genetic code (DNA, RNA), protein synthesis, cell membrane transport, and signal transduction.
+
+== Proto-biochemistry ==
+
+In a sense, the study of biochemistry can be considered to have started in ancient times, for example when biology first began to interest society—as the ancient Chinese developed a system of medicine based on yin and yang, and also the five phases, which both resulted from alchemical and biological interests. Its beginning in the ancient Indian culture was linked to an interest in medicine, as they developed the concept of three humors that were similar to the Greeks' four humours (see humorism). They also delved into the interest of bodies being composed of tissues. The ancient Greeks' conception of biochemistry was linked with their ideas on matter and disease, where good health was thought to come from a balance of the four elements and four humors in the human body. As in the majority of early sciences, the Islamic world contributed significantly to early biological advancements as well as alchemical advancements; especially with the introduction of clinical trials and clinical pharmacology presented in Avicenna's The Canon of Medicine. On the side of chemistry, early advancements were heavily attributed to exploration of alchemical interests but also included: metallurgy, the scientific method, and early theories of atomism. In more recent times, the study of chemistry was marked by milestones such as the development of Mendeleev's periodic table, Dalton's atomic model, and the conservation of mass theory. This last mention has the most importance of the three due to the fact that this law intertwines chemistry with thermodynamics in an intercalated manner.
+
+== Enzymes ==

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+---
+title: "History of biochemistry"
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+category: "reference"
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+date_saved: "2026-05-05T03:59:19.261593+00:00"
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+---
+
+As early as the late 18th century and early 19th century, the digestion of meat by stomach secretions and the conversion of starch to sugars by plant extracts and saliva were known. However, the mechanism by which this occurred had not been identified.
+In the 19th century, when studying the fermentation of sugar to alcohol by yeast, Louis Pasteur concluded that this fermentation was catalyzed by a vital force contained within the yeast cells called ferments, which he thought functioned only within living organisms. He wrote that "alcoholic fermentation is an act correlated with the life and organization of the yeast cells, not with the death or putrefaction of the cells."
+In 1833 Anselme Payen discovered the first enzyme, diastase, and in 1878 German physiologist Wilhelm Kühne (1837–1900) coined the term enzyme, which comes from Greek ενζυμον 'in leaven', to describe this process. The word enzyme was used later to refer to nonliving substances such as pepsin, and the word ferment was used to refer to chemical activity produced by living organisms.
+In 1897 Eduard Buchner began to study the ability of yeast extracts to ferment sugar despite the absence of living yeast cells. In a series of experiments at the University of Berlin, he found that the sugar was fermented even when there were no living yeast cells in the mixture. He named the enzyme that brought about the fermentation of sucrose zymase. In 1907 he received the Nobel Prize in Chemistry "for his biochemical research and his discovery of cell-free fermentation". Following Buchner's example; enzymes are usually named according to the reaction they carry out. Typically the suffix -ase is added to the name of the substrate (e.g., lactase is the enzyme that cleaves lactose) or the type of reaction (e.g., DNA polymerase forms DNA polymers). 
+
+Having shown that enzymes could function outside a living cell, the next step was to determine their biochemical nature. Many early workers noted that enzymatic activity was associated with proteins, but several scientists (such as Nobel laureate Richard Willstätter) argued that proteins were merely carriers for the true enzymes and that proteins per se were incapable of catalysis. However, in 1926, James B. Sumner showed that the enzyme urease was a pure protein and crystallized it; Sumner did likewise for the enzyme catalase in 1937. The conclusion that pure proteins can be enzymes was definitively proved by Northrop and Stanley, who worked on the digestive enzymes pepsin (1930), trypsin, and chymotrypsin. These three scientists were awarded the 1946 Nobel Prize in Chemistry.
+This discovery, that enzymes could be crystallized, meant that scientists eventually could solve their structures by x-ray crystallography. This was first done for lysozyme, an enzyme found in tears, saliva, and egg whites that digests the coating of some bacteria; the structure was solved by a group led by David Chilton Phillips and published in 1965. This high-resolution structure of lysozyme marked the beginning of the field of structural biology and the effort to understand how enzymes work at an atomic level of detail.
+
+== Metabolism ==
+
+=== Early metabolic interest ===
+
+The term metabolism is derived from the Greek μεταβολισμός, metabolismos for 'change', or 'overthrow'. The history of the scientific study of metabolism spans 800 years. The earliest of all metabolic studies began during the early thirteenth century (1213–1288) by a Muslim scholar from Damascus named Ibn al-Nafis. al-Nafis stated in his most well-known work Theologus Autodidactus that "that body and all its parts are in a continuous state of dissolution and nourishment, so they are inevitably undergoing permanent change." Although al-Nafis was the first documented physician to have an interest in biochemical concepts, the first controlled experiments in human metabolism were published by Santorio Santorio in 1614 in his book Ars de statica medecina. This book describes how he weighed himself before and after eating, sleeping, working, sex, fasting, drinking, and excreting. He found that most of the food he took in was lost through what he called "insensible perspiration".
+
+=== Metabolism: 20th century – present ===
+One of the most prolific of these modern biochemists was Hans Krebs who made huge contributions to the study of metabolism. Krebs was a student of extremely important Otto Warburg, and wrote a biography of Warburg by that title in which he presents Warburg as being educated to do for biological chemistry what Fischer did for organic chemistry.  Which he did. Krebs discovered the urea cycle and later, working with Hans Kornberg, the citric acid cycle and the glyoxylate cycle. These discoveries led to Krebs being awarded the Nobel Prize in physiology in 1953, which was shared with the German biochemist Fritz Albert Lipmann who also codiscovered the essential cofactor coenzyme A.
+
+==== Glucose absorption ====
+In 1960, the biochemist Robert K. Crane revealed his discovery of the sodium-glucose cotransport as the mechanism for intestinal glucose absorption. This was the very first proposal of a coupling between the fluxes of an ion and a substrate that has been seen as sparking a revolution in biology. This discovery, however, would not have been possible if it were not for the discovery of the molecule glucose's structure and chemical makeup. These discoveries are largely attributed to the German chemist Emil Fischer who received the Nobel Prize in chemistry nearly 60 years earlier.
+
+=== Glycolysis ===

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+title: "History of biochemistry"
+chunk: 3/3
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+category: "reference"
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+date_saved: "2026-05-05T03:59:19.261593+00:00"
+instance: "kb-cron"
+---
+
+Since metabolism focuses on the breaking down (catabolic processes) of molecules and the building of larger molecules from these particles (anabolic processes), the use of glucose and its involvement in the formation of adenosine triphosphate (ATP) is fundamental to this understanding. The most frequent type of glycolysis found in the body is the type that follows the Embden-Meyerhof-Parnas (EMP) Pathway, which was discovered by Gustav Embden, Otto Meyerhof, and Jakob Karol Parnas. These three men discovered that glycolysis is a strongly determinant process for the efficiency and production of the human body. The significance of the pathway shown in the adjacent image is that by identifying the individual steps in this process doctors and researchers are able to pinpoint sites of metabolic malfunctions such as pyruvate kinase deficiency that can lead to severe anemia. This is most important because cells, and therefore organisms, are not capable of surviving without proper functioning metabolic pathways.
+
+== Instrumental advancements (20th century) ==
+
+Since then, biochemistry has advanced, especially since the mid-20th century, with the development of new techniques such as chromatography, X-ray diffraction, NMR spectroscopy, radioisotopic labelling, electron microscopy and molecular dynamics simulations. These techniques allowed for the discovery and detailed analysis of many molecules and metabolic pathways of the cell, such as glycolysis and the Krebs cycle (citric acid cycle). The example of an NMR instrument shows that some of these instruments, such as the HWB-NMR, can be very large in size and can cost anywhere from a few thousand dollars to millions of dollars ($16 million for the one shown here).
+
+=== Polymerase chain reaction ===
+
+Polymerase chain reaction (PCR) is the primary gene amplification technique that has revolutionized modern biochemistry. Polymerase chain reaction was developed by Kary Mullis in 1983. There are four steps to a proper polymerase chain reaction: 1) denaturation 2) extension 3) insertion (of gene to be expressed) and finally 4) amplification of the inserted gene. These steps with simple illustrative examples of this process can be seen in the image below and to the right of this section. This technique allows for the copy of a single gene to be amplified into hundreds or even millions of copies and has become a cornerstone in the protocol for any biochemist that wishes to work with bacteria and gene expression. PCR is not only used for gene expression research but is also capable of aiding laboratories in diagnosing certain diseases such a lymphomas, some types of leukemia, and other malignant diseases that can sometimes puzzle doctors. Without polymerase chain reaction development, there are many advancements in the field of bacterial study and protein expression study that would not have come to fruition. The development of the theory and process of polymerase chain reaction is essential but the invention of the thermal cycler is equally as important because the process would not be possible without this instrument. This is yet another testament to the fact that the advancement of technology is just as crucial to sciences such as biochemistry as is the painstaking research that leads to the development of theoretical concepts.
+
+== See also ==
+Agricultural chemistry § History
+History of biology
+History of chemistry
+History of molecular biology
+History of chromatography
+History of RNA biology
+Metabolism
+Citric acid cycle
+
+== References ==
+
+== Further reading ==
+Fruton, Joseph S.  Proteins, Enzymes, Genes: The Interplay of Chemistry and Biology.  Yale University Press: New Haven, 1999.  ISBN 0-300-07608-8
+Kohler, Robert.  From Medical Chemistry to Biochemistry: The Making of a Biomedical Discipline. Cambridge University Press, 1982.

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+---
+title: "History of botany"
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+category: "reference"
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+date_saved: "2026-05-05T03:59:20.683361+00:00"
+instance: "kb-cron"
+---
+
+The history of botany examines the human effort to understand life on Earth by tracing the historical development of the discipline of botany, the part of natural science dealing with organisms traditionally treated as plants.
+Rudimentary botanical science began with empirically based plant lore passed from generation to generation in the oral traditions of Paleolithic hunter-gatherers. The first writings that show human curiosity about plants themselves, rather than the uses that could be made of them, appear in ancient Greece and ancient India. In Ancient Greece, the teachings of Aristotle's student Theophrastus at the Lyceum in ancient Athens in about 350 BC are considered the starting point for Western botany. In ancient India, the Vṛkṣāyurveda, attributed to Parashara, is also considered one of the earliest texts to describe various branches of botany.
+In Europe, botanical science was soon overshadowed by a medieval preoccupation with the medicinal properties of plants that lasted more than 1000 years. During this time, the medicinal works of classical antiquity were reproduced in manuscripts and books called herbals. In China and the Arab world, the Greco-Roman work on medicinal plants was preserved and extended.
+In Europe, the Renaissance of the 14th–17th centuries heralded a scientific revival during which botany gradually emerged from natural history as an independent science, distinct from medicine and agriculture. Herbals were replaced by floras: books that described the native plants of local regions. The invention of the microscope stimulated the study of plant anatomy, and the first carefully designed experiments in plant physiology were performed. With the expansion of trade and exploration beyond Europe, the many new plants being discovered were subjected to an increasingly rigorous process of naming, description, and classification.
+Progressively more sophisticated scientific technology has aided the development of contemporary botanical offshoots in the plant sciences, ranging from the applied fields of economic botany (notably agriculture, horticulture and forestry), to the detailed examination of the structure and function of plants and their interaction with the environment over many scales from the large-scale global significance of vegetation and plant communities (biogeography and ecology) through to the small scale of subjects like cell theory, molecular biology and plant biochemistry.
+
+== Introduction ==
+
+Botany (Greek Βοτάνη (botanē) meaning "pasture", "herbs" "grass", or "fodder"; Medieval Latin botanicus – herb, plant) and zoology are, historically, the core disciplines of biology whose history is closely associated with the natural sciences chemistry, physics and geology. A distinction can be made between botanical science in a pure sense, as the study of plants themselves, and botany as applied science, which studies the human use of plants. Early natural history divided pure botany into three main streams morphology-classification, anatomy and physiology – that is, external form, internal structure, and functional operation. The most obvious topics in applied botany are horticulture, forestry and agriculture although there are many others like weed science, plant pathology, floristry, pharmacognosy, economic botany and ethnobotany which lie outside modern courses in botany. Since the origin of botanical science there has been a progressive increase in the scope of the subject as technology has opened up new techniques and areas of study. Modern molecular systematics, for example, entails the principles and techniques of taxonomy, molecular biology, computer science and more.
+Within botany, there are a number of sub-disciplines that focus on particular plant groups, each with their own range of related studies (anatomy, morphology etc.). Included here are: phycology (algae), pteridology (ferns), bryology (mosses and liverworts) and palaeobotany (fossil plants) and their histories are treated elsewhere (see side bar). To this list can be added mycology, the study of fungi, which were once treated as plants, but are now ranked as a unique kingdom.
+
+== Ancient knowledge ==
+
+Nomadic hunter-gatherer societies passed on, by oral tradition, what they knew (their empirical observations) about the different kinds of plants that they used for food, shelter, poisons, medicines, for ceremonies and rituals etc. The uses of plants by these pre-literate societies influenced the way the plants were named and classified; their uses were embedded in folk-taxonomies, the way they were grouped according to use in everyday communication. The nomadic life-style was drastically changed when settled communities were established in about twelve centres around the world during the Neolithic Revolution which extended from about 10,000 to 2500 years ago depending on the region. With these communities came the development of the technology and skills needed for the domestication of plants and animals and the emergence of the written word provided evidence for the passing of systematic knowledge and culture from one generation to the next.
+
+=== Plant lore and plant selection ===
+
+During the Neolithic Revolution, plant knowledge increased most obviously through the use of plants for food and medicine.  All of today's staple foods were domesticated in prehistoric times as a gradual process of selection of higher-yielding varieties took place, possibly unknowingly, over hundreds to thousands of years. Legumes were cultivated on all continents but cereals made up most of the regular diet; rice in East Asia, wheat and barley in the Middle east, and maize in Central and South America. By Greco-Roman times, popular food plants of today, including grapes, apples, figs, and olives, were being listed as named varieties in early manuscripts. The botanical authority William Stearn observed that "cultivated plants are mankind's most vital and precious heritage from remote antiquity".
+It is also from the Neolithic, in about 3000 BC, that we glimpse the first known illustrations of plants and read descriptions of impressive gardens in Egypt. However protobotany, the first pre-scientific written record of plants, did not begin with food, but came out of the medicinal literature of Egypt, China, Mesopotamia and India. The botanical historian Alan Morton noted that agriculture was the occupation of the poor and uneducated, while medicine was the realm of socially influential shamans, priests, apothecaries, magicians and physicians, who were more likely to record their knowledge for posterity.
+
+=== Early botany ===

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+title: "History of botany"
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+date_saved: "2026-05-05T03:59:20.683361+00:00"
+instance: "kb-cron"
+---
+
+==== Ancient India ====
+Early Indian texts, like the Vedas mention plants with magical properties. The Sushruta Samhita, describes over 700 plants used for medicinal purposes. This text reflects a level of medical knowledge and practice comparable to ancient Egypt. Notably, the Sushruta Samhita categorizes food plants based on their parts used, taste, and dietary effects. While lacking detailed botanical descriptions beyond occasional habitat or foliage references, the text demonstrates close observation of plants. This is evident in the classification of sugarcane varieties and the listing of fungi based on their growth medium. The Charaka Samhitā, foundational Ayurvedic text, presents the earliest known plant classification system in India, using habitat, presence of flowers/fruits, and reproduction as criteria.
+
+=== Classical antiquity ===
+
+==== Classical Greece ====
+Ancient Athens, of the 6th century BC, was the busy trade centre at the confluence of Egyptian, Mesopotamian and Minoan cultures at the height of Greek colonisation of the Mediterranean. The philosophical thought of this period ranged freely through many subjects. Empedocles (490–430 BC) foreshadowed Darwinian evolutionary theory in a crude formulation of the mutability of species and natural selection. The physician Hippocrates (460–370 BC) avoided the prevailing superstition of his day and approached healing by close observation and the test of experience. At this time, a genuine non-anthropocentric curiosity about plants emerged. The major works written about plants extended beyond the description of their medicinal uses to the topics of plant geography, morphology, physiology, nutrition, growth and reproduction.
+
+==== Theophrastus and the origin of botanical science ====
+
+Foremost among the scholars studying botany was Theophrastus of Eressus (Greek: Θεόφραστος; c. 371–287 BC) who has been frequently referred to as the "Father of Botany". He was a student and close friend of Aristotle (384–322 BC) and succeeded him as head of the Lyceum (an educational establishment like a modern university) in Athens with its tradition of peripatetic philosophy. Aristotle's special treatise on plants — θεωρία περὶ φυτῶν — is now lost, although there are many botanical observations scattered throughout his other writings (these have been assembled by Christian Wimmer in Phytologiae Aristotelicae Fragmenta, 1836) but they give little insight into his botanical thinking. The Lyceum prided itself in a tradition of systematic observation of causal connections, critical experiment and rational theorizing. Theophrastus challenged the superstitious medicine employed by the physicians of his day, called rhizotomi, and also the control over medicine exerted by priestly authority and tradition. Together with Aristotle, he had tutored Alexander the Great whose military conquests were carried out with all the scientific resources of the day, the Lyceum garden probably containing many botanical trophies collected during his campaigns as well as other explorations in distant lands. It was in this garden where he gained much of his plant knowledge.
+
+===== Enquiry into Plants and Causes of Plants =====
+
+Theophrastus's major botanical works were the Enquiry into Plants (Historia Plantarum) and Causes of Plants (Causae Plantarum) which were his lecture notes for the Lyceum. The opening sentence of the Enquiry reads like a botanical manifesto:
+
+We must consider the distinctive characters and the general nature of plants from the point of view of their morphology, their behaviour under external conditions, their mode of generation and the whole course of their life.
+The Enquiry is 9 books of "applied" botany dealing with the forms and classification of plants and economic botany, examining the techniques of agriculture (relationship of crops to soil, climate, water and habitat) and horticulture. He described some 500 plants in detail, often including descriptions of habitat and geographic distribution, and he recognised some plant groups that can be recognised as modern-day plant families. Some names he used, like Crataegus, Daucus and Asparagus have persisted until today. His second book Causes of Plants covers plant growth and reproduction (akin to modern physiology). Like Aristotle, he grouped plants into "trees", "undershrubs", "shrubs" and "herbs" but he also made several other important botanical distinctions and observations. He noted that plants could be annuals, perennials and biennials, they were also either monocotyledons or dicotyledons and he also noticed the difference between determinate and indeterminate growth and details of floral structure including the degree of fusion of the petals, position of the ovary and more. These lecture notes of Theophrastus comprise the first clear exposition of the rudiments of plant anatomy, physiology, morphology and ecology — presented in a way that would not be matched for another eighteen centuries.
+
+==== Pedanius Dioscorides ====
+
+A full synthesis of ancient Greek pharmacology was compiled in De Materia Medica c. 60 AD by Pedanius Dioscorides (c. 40-90 AD) who was a Greek physician with the Roman army. This work proved to be the definitive text on medicinal herbs, both oriental and occidental, for fifteen hundred years until the dawn of the European Renaissance being slavishly copied again and again throughout this period. Though rich in medicinal information with descriptions of about 600 medicinal herbs, the botanical content of the work was extremely limited.
+
+==== Ancient Rome ====
+
+The Romans contributed little to the foundations of botanical science laid by the ancient Greeks, but made a sound contribution to our knowledge of applied botany as agriculture. In works titled De Re Rustica, four Roman writers contributed to a compendium Scriptores Rei Rusticae, published from the Renaissance on, which set out the principles and practice of agriculture. These authors were Cato (234–149 BC), Varro (116–27 BC) and, in particular, Columella (4–70 AD) and Palladius (4th century AD). 
+
+===== Pliny the Elder =====
+Roman encyclopaedist Pliny the Elder (23–79 AD) deals with plants in Books 12 to 26 of his 37-volume highly influential work Naturalis Historia in which he frequently quotes Theophrastus but with a lack of botanical insight although he does, nevertheless, draw a distinction between true botany on the one hand, and farming and medicine on the other. It is estimated that at the time of the Roman Empire between 1300 and 1400 plants had been recorded in the West.

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+title: "History of botany"
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+category: "reference"
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+date_saved: "2026-05-05T03:59:20.683361+00:00"
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+---
+
+=== Ancient China ===
+In ancient China, lists of different plants and herb concoctions for pharmaceutical purposes date back to at least the time of the Warring States (481 BC-221 BC). Many Chinese writers over the centuries contributed to the written knowledge of herbal pharmaceutics. The Chinese dictionary-encyclopaedia Erh Ya probably dates from about 300 BC and describes about 334 plants classed as trees or shrubs, each with a common name and illustration. The Han Dynasty (202 BC-220 AD) includes the notable work of the Huangdi Neijing and the famous pharmacologist Zhang Zhongjing.
+
+== Medieval knowledge ==
+
+=== Medicinal plants of the early Middle Ages ===
+
+In Western Europe, after Theophrastus, botany passed through a bleak period of 1800 years when little progress was made and, indeed, many of the early insights were lost. As Europe entered the Middle Ages (5th to 15th centuries), China, India and the Arab world enjoyed a golden age. 
+
+==== Medieval China ====
+
+Chinese philosophy had followed a similar path to that of the ancient Greeks. Between 100 and 1700 AD, many new works on pharmaceutical botany were produced. The 11th century scientists and statesmen Su Song and Shen Kuo compiled learned treatises on natural history, emphasising herbal medicine. Among the pharmaceutical botany works were encyclopaedic accounts and treatises compiled for the Chinese imperial court. These were free of superstition and myth with carefully researched descriptions and nomenclature; they included cultivation information and notes on economic and medicinal uses — and even elaborate monographs on ornamental plants. But there was no experimental method and no analysis of the plant sexual system, nutrition, or anatomy.
+
+==== Medieval India ====
+In India, simple artificial plant classification became more botanical with the work of Parashara (c. 400 – c. 500 AD), the author of Vṛksayurveda (the science of life of trees). Important medieval Indian works of plant physiology include the Prthviniraparyam of Udayana, Nyayavindutika of Dharmottara, Saddarsana-samuccaya of Gunaratna, and Upaskara of Sankaramisra.
+
+==== Islamic Golden Age ====
+
+The 400-year period from the 9th to 13th centuries AD was the Islamic Renaissance, a time when Islamic culture and science thrived. Greco-Roman texts were preserved, copied and extended although new texts always emphasised the medicinal aspects of plants. Kurdish biologist Ābu Ḥanīfah Āḥmad ibn Dawūd Dīnawarī (828–896 AD) is known as the founder of Arabic botany; his Kitâb al-nabât ('Book of Plants') describes 637 species, discussing plant development from germination to senescence and including details of flowers and fruits. The Mutazilite philosopher and physician Ibn Sina (Avicenna) (c. 980–1037 AD) was another influential figure, his The Canon of Medicine being a landmark in the history of medicine treasured until the Enlightenment.
+
+=== The Silk Road ===
+Following the fall of Constantinople (1453), the newly expanded Ottoman Empire welcomed European embassies in its capital, which in turn became the sources of plants from those regions to the east which traded with the empire. In the following century, twenty times as many plants entered Europe along the Silk Road as had been transported in the previous two thousand years, mainly as bulbs. Others were acquired primarily for their alleged medicinal value. Initially, Italy benefited from this new knowledge, especially Venice, which traded extensively with the East. From there, these new plants rapidly spread to the rest of Western Europe. By the middle of the sixteenth century, there was already a flourishing export trade of various bulbs from Turkey to Europe.
+
+=== The Age of Herbals ===
+
+In the European Middle Ages of the 15th and 16th centuries, the lives of European citizens were based around agriculture but when printing arrived, with movable type and woodcut illustrations, it was not treatises on agriculture that were published, but lists of medicinal plants with descriptions of their properties or "virtues". These first plant books, known as herbals showed that botany was still a part of medicine, as it had been for most of ancient history. Authors of herbals were often curators of university gardens, and most herbals were derivative compilations of classic texts, especially De Materia Medica. 
+
+The authors of the oldest herbals of the 16th century, Brunfels, Fuchs, Bock, Mattioli and others, regarded plants mainly as the vehicles of medicinal virtues. ... Their chief object was to discover the plants employed by the physicians of antiquity, the knowledge of which had been lost in later times. The corrupt texts of Theophrastus, Dioscorides, Pliny and Galen had been in many respects improved and illustrated by ... Italian commentators of the 15th and ... early part of the 16th century; but there was one imperfection which no criticism could remove,—the highly unsatisfactory descriptions of the old authors or the entire absence of descriptions.It was moreover at first assumed that the plants described by the Greek physicians must grow wild in Germany also, and generally in the rest of Europe; each author identified a different native plant with some one mentioned by Dioscorides or Theophrastus or others, and thus there arose [in] the 16th century a confusion of nomenclature.
+However, the need for accurate and detailed plant descriptions meant that some herbals were more botanical than medicinal. 

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+
+A great advance was made by the first German composers of herbals, who went straight to nature, described the wild plants growing around them and had figures of them carefully executed in wood. Thus was made the first beginning of a really scientific examination of plants, though the aims pursued were not yet truly scientific, for no questions were proposed as to the nature of plants, their organisation or mutual relations; the only point of interest was the knowledge of individual forms and of their medicinal virtues.
+German Otto Brunfels's (1464–1534) Herbarum Vivae Icones (1530) contained descriptions of about 47 species new to science combined with accurate illustrations. His fellow countryman Hieronymus Bock's (1498–1554) Kreutterbuch of 1539 described plants he found in nearby woods and fields and these were illustrated in the 1546 edition. However, it was Valerius Cordus (1515–1544) who pioneered the formal botanical description that detailed both flowers and fruits, some anatomy including the number of chambers in the ovary, and the type of ovule placentation. He also made observations on pollen and distinguished between inflorescence types. His five-volume Historia Plantarum was published about 18 years after his early death aged 29 in 1561–1563. In England, William Turner (1515–1568) in his Libellus De Re Herbaria Novus (1538) published names, descriptions and localities of many native British plants and in Holland Rembert Dodoens (1517–1585), in Stirpium Historiae (1583), included descriptions of many new species from the Netherlands in a scientific arrangement. 
+Herbals contributed to botany by setting in train the science of plant description, classification, and botanical illustration. Up to the 17th century, botany and medicine were one and the same but those books emphasising medicinal aspects eventually omitted the plant lore to become modern pharmacopoeias; those that omitted the medicine became more botanical and evolved into the modern compilations of plant descriptions we call Floras. These were often backed by specimens deposited in a herbarium which was a collection of dried plants that verified the plant descriptions given in the Floras. The transition from herbal to Flora marked the final separation of botany from medicine.
+
+== The Renaissance and Age of Enlightenment (1550–1800) ==
+
+The revival of learning during the European Renaissance renewed interest in plants. The church, feudal aristocracy and an increasingly influential merchant class that supported science and the arts, now jostled in a world of increasing trade. Sea voyages of exploration returned botanical treasures to the large public, private, and newly established botanic gardens, and introduced an eager population to novel crops, drugs and spices from Asia, the East Indies and the New World.
+The number of scientific publications increased. In England, for example, scientific communication and causes were facilitated by learned societies like Royal Society (founded in 1660) and the Linnaean Society (founded in 1788): there was also the support and activities of botanical institutions like the Jardin du Roi in Paris, Chelsea Physic Garden, Royal Botanic Gardens Kew, and the Oxford and Cambridge Botanic Gardens, as well as the influence of renowned private gardens and wealthy entrepreneurial nurserymen. By the early 17th century the number of plants described in Europe had risen to about 6000. The 18th century Enlightenment values of reason and science coupled with new voyages to distant lands instigating another phase of encyclopaedic plant identification, nomenclature, description and illustration, "flower painting" possibly at its best in this period of history. Plant trophies from distant lands decorated the gardens of Europe's powerful and wealthy in a period of enthusiasm for natural history, especially botany (a preoccupation sometimes referred to as "botanophilia") that is never likely to recur. Often such exotic new plant imports (primarily from Turkey), when they first appeared in print in English, lacked common names in the language.
+During the 18th century, botany was one of the few sciences considered appropriate for genteel educated women. Around 1760, with the popularization of the Linnaean system, botany became much more widespread among educated women who painted plants, attended classes on plant classification, and collected herbarium specimens although emphasis was on the healing properties of plants rather than plant reproduction which had overtones of sexuality. Women began publishing on botanical topics and children's books on botany appeared by authors like Charlotte Turner Smith. Cultural authorities argued that education through botany created culturally and scientifically aware citizens, part of the thrust for 'improvement' that characterised the Enlightenment. However, in the early 19th century with the recognition of botany as an official science, women were again excluded from the discipline. Compared to other sciences, however, in botany the number of female researchers, collectors, or illustrators has always been remarkably high.
+
+=== Botanical gardens and herbaria ===

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+
+Public and private gardens have always been strongly associated with the historical unfolding of botanical science.
+Early botanical gardens were physic gardens, repositories for the medicinal plants described in the herbals. As they were generally associated with universities or other academic institutions, the plants were also used for study. The directors of these gardens were eminent physicians with an educational role as "scientific gardeners" and it was staff of these institutions that produced many of the published herbals.
+The botanical gardens of the modern tradition were established in northern Italy, the first being at Pisa (1544), founded by Luca Ghini (1490–1556). Although part of a medical faculty, the first chair of materia medica, essentially a chair in botany, was established in Padua in 1533. Then in 1534, Ghini became Reader in materia medica at Bologna University, where Ulisse Aldrovandi established a similar garden in 1568 (see below).  Collections of pressed and dried specimens were called a hortus siccus (garden of dry plants) and the first accumulation of plants in this way (including the use of a plant press) is attributed to Ghini. Buildings called herbaria housed these specimens mounted on card with descriptive labels. Stored in cupboards in systematic order, they could be preserved in perpetuity and easily transferred or exchanged with other institutions, a taxonomic procedure that is still used today.
+By the 18th century, the physic gardens had been transformed into "order beds" that demonstrated the classification systems that were being devised by botanists of the day — but they also had to accommodate the influx of curious, beautiful and new plants pouring in from voyages of exploration that were associated with European colonial expansion.
+
+=== From Herbal to Flora ===
+
+Plant classification systems of the 17th and 18th centuries now related plants to one another and not to man, marking a return to the non-anthropocentric botanical science promoted by Theophrastus over 1500 years before. In England, various herbals in either Latin or English were mainly compilations and translations of continental European works, of limited relevance to the British Isles. This included the rather unreliable work of Gerard (1597). The first systematic attempt to collect information on British plants was that of Thomas Johnson (1629), who was later to issue his own revision of Gerard's work (1633–1636).
+However, Johnson was not the first apothecary or physician to organise botanical expeditions to systematise their local flora. In Italy, Ulisse Aldrovandi (1522 – 1605) organised an expedition to the Sibylline mountains in Umbria in 1557, and compiled a local Flora. He then began to disseminate his findings amongst other European scholars, forming an early network of knowledge sharing "molti amici in molti luoghi" (many friends in many places), including Charles de l'Écluse (Clusius) (1526 – 1609) at Montpellier and Jean de Brancion at Malines. Between them, they started developing Latin names for plants, in addition to their common names. The exchange of information and specimens between scholars was often associated with the founding of botanical gardens (above), and to this end Aldrovandi founded one of the earliest at his university in Bologna, the Orto Botanico di Bologna in 1568.
+In France, Clusius journeyed throughout most of Western Europe, making discoveries in the vegetable kingdom along the way. He compiled Flora of Spain (1576), and Austria and Hungary (1583). He was the first to propose dividing plants into classes. Meanwhile, in Switzerland, from 1554, Conrad Gessner (1516 – 1565) made regular explorations of the Swiss Alps from his native Zurich and discovered many new plants. He proposed that there were groups or genera of plants.  He said that each genus was composed of many species and that these were defined by similar flowers and fruits. This principle of organisation laid the groundwork for future botanists. He wrote his important Historia Plantarum shortly before his death. At Malines, in Flanders he established and maintained the botanical gardens of Jean de Brancion from 1568 to 1573, and first encountered tulips.
+This approach coupled with the new Linnaean system of binomial nomenclature resulted in plant encyclopaedias without medicinal information called Floras that meticulously described and illustrated the plants growing in particular regions. The 17th century also marked the beginning of experimental botany and application of a rigorous scientific method, while improvements in the microscope launched the new discipline of plant anatomy whose foundations, laid by the careful observations of Englishman Nehemiah Grew and Italian Marcello Malpighi, would last for 150 years.
+
+=== Botanical exploration ===
+
+More new lands were opening up to European colonial powers, the botanical riches being returned to European botanists for description. This was a romantic era of botanical explorers, intrepid plant hunters and gardener-botanists. Significant botanical collections came from: the West Indies (Hans Sloane (1660–1753)); China (James Cunningham); the spice islands of the East Indies (Moluccas, George Rumphius (1627–1702)); China and Mozambique (João de Loureiro (1717–1791)); West Africa (Michel Adanson (1727–1806)) who devised his own classification scheme and forwarded a crude theory of the mutability of species; Canada, Hebrides, Iceland, New Zealand by Captain James Cook's chief botanist Joseph Banks (1743–1820).
+
+=== Classification and morphology ===

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+By the middle of the 18th century, the botanical booty resulting from the era of exploration was accumulating in gardens and herbaria – and it needed to be systematically catalogued. This was the task of the taxonomists, the plant classifiers.
+Plant classifications have changed over time from "artificial" systems based on general habit and form, to pre-evolutionary "natural" systems expressing similarity using one to many characters, leading to post-evolutionary "natural" systems that use characters to infer evolutionary relationships.
+Italian physician Andrea Caesalpino (1519–1603) studied medicine and taught botany at the University of Pisa for about 40 years eventually becoming Director of the Botanic Garden of Pisa from 1554 to 1558. His sixteen-volume De Plantis (1583) described 1500 plants and his herbarium of 260 pages and 768 mounted specimens still remains. Caesalpino proposed classes based largely on the detailed structure of the flowers and fruit;  he also applied the concept of the genus. He was the first to try and derive principles of natural classification reflecting the overall similarities between plants and he produced a classification scheme well in advance of its day. Gaspard Bauhin (1560–1624) produced two influential publications Prodromus Theatrici Botanici (1620) and Pinax (1623). These brought order to the 6000 species now described and in the latter he used binomials and synonyms that may well have influenced Linnaeus's thinking. He also insisted that taxonomy should be based on natural affinities.
+
+To sharpen the precision of description and classification, Joachim Jung (1587–1657) compiled a much-needed botanical terminology which has stood the test of time. English botanist John Ray (1623–1705) built on Jung's work to establish the most elaborate and insightful classification system of the day. His observations started with the local plants of Cambridge where he lived, with the Catalogus Stirpium circa Cantabrigiam Nascentium (1860) which later expanded to his Synopsis Methodica Stirpium Britannicarum, essentially the first British Flora. Although his Historia Plantarum (1682, 1688, 1704) provided a step towards a world Flora as he included more and more plants from his travels, first on the continent and then beyond. He extended Caesalpino's natural system with a more precise definition of the higher classification levels, deriving many modern families in the process, and asserted that all parts of plants were important in classification. He recognised that variation arises from both internal (genotypic) and external environmental (phenotypic) causes and that only the former was of taxonomic significance. He was also among the first experimental physiologists. The Historia Plantarum can be regarded as the first botanical synthesis and textbook for modern botany. According to botanical historian Alan Morton, Ray "influenced both the theory and the practice of botany more decisively than any other single person in the latter half of the seventeenth century". Ray's family system was later extended by Pierre Magnol (1638–1715) and Joseph de Tournefort (1656–1708), a student of Magnol, achieved notoriety for his botanical expeditions, his emphasis on floral characters in classification, and for reviving the idea of the genus as the basic unit of classification.
+Above all it was Swedish Carl Linnaeus (1707–1778), who eased the task of plant cataloguing. He adopted a sexual system of classification using stamens and pistils as important characters. Among his most important publications were Systema Naturae (1735), Genera Plantarum (1737), and Philosophia Botanica (1751) but it was in his Species Plantarum (1753) that he gave every species a binomial thus setting the path for the future accepted method of designating the names of all organisms. Linnaean thought and books dominated the world of taxonomy for nearly a century. His sexual system was later elaborated by Bernard de Jussieu (1699–1777) whose nephew Antoine-Laurent de Jussieu (1748–1836) extended it yet again to include about 100 orders (present-day families). Frenchman Michel Adanson (1727–1806) in his Familles des Plantes (1763, 1764), apart from extending the current system of family names, emphasized that a natural classification must be based on a consideration of all characters, even though these may later be given different emphasis according to their diagnostic value for the particular plant group. Adanson's method has, in essence, been followed to this day.
+18th century plant taxonomy bequeathed to the 19th century a precise binomial nomenclature and botanical terminology, a system of classification based on natural affinities, and a clear idea of the ranks of family, genus and species — although the taxa to be placed within these ranks remains, as always, the subject of taxonomic research.
+
+=== Anatomy ===
+ 
+
+In the first half of the 18th century, botany was beginning to move beyond descriptive science into experimental science. Although the microscope was invented in 1590, it was only in the late 17th century that lens grinding provided the resolution needed to make major discoveries. Antony van Leeuwenhoek is a notable example of an early lens grinder who achieved remarkable resolution with his single-lens microscopes. Important general biological observations were made by Robert Hooke (1635–1703) but the foundations of plant anatomy were laid by Italian Marcello Malpighi (1628–1694) of the University of Bologna in his Anatome Plantarum (1675) and Royal Society Englishman Nehemiah Grew (1628–1711) in his The Anatomy of Plants Begun (1671) and Anatomy of Plants (1682). These botanists explored what is now called developmental anatomy and morphology by carefully observing, describing and drawing the developmental transition from seed to mature plant, recording stem and wood formation. This work included the discovery and naming of parenchyma and stomata.
+
+=== Physiology ===

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+In plant physiology, research interest was focused on the movement of sap and the absorption of substances through the roots. Jan Helmont (1577–1644) by experimental observation and calculation, noted that the increase in weight of a growing plant cannot be derived purely from the soil, and concluded it must relate to water uptake. Englishman Stephen Hales (1677–1761) established by quantitative experiment that there is uptake of water by plants and a loss of water by transpiration and that this is influenced by environmental conditions: he distinguished "root pressure", "leaf suction" and "imbibition" and also noted that the major direction of sap flow in woody tissue is upward. His results were published in Vegetable Staticks (1727) He also noted that "air makes a very considerable part of the substance of vegetables". English chemist Joseph Priestley (1733–1804) is noted for his discovery of oxygen (as now called) and its production by plants. Later, Jan Ingenhousz (1730–1799) observed that only in sunlight do the green parts of plants absorb air and release oxygen, this being more rapid in bright sunlight while, at night, the air (CO2) is released from all parts. His results were published in Experiments upon vegetables (1779) and with this the foundations for 20th century studies of carbon fixation were laid. From his observations, he sketched the cycle of carbon in nature even though the composition of carbon dioxide was yet to be resolved. Studies in plant nutrition had also progressed. In 1804, Nicolas-Théodore de Saussure's (1767–1845) Recherches Chimiques sur la Végétation was an exemplary study of scientific exactitude that demonstrated the similarity of respiration in both plants and animals, that the fixation of carbon dioxide includes water, and that just minute amounts of salts and nutrients (which he analysed in chemical detail from plant ash) have a powerful influence on plant growth.
+
+=== Plant sexuality ===
+
+It was Rudolf Camerarius (1665–1721) who was the first to establish plant sexuality conclusively by experiment. He declared in a letter to a colleague, dated 1694 and titled De Sexu Plantarum Epistola, that "no ovules of plants could ever develop into seeds from the female style and ovary without first being prepared by the pollen from the stamens, the male sexual organs of the plant".
+
+Some time later, the German academic and natural historian Joseph Kölreuter (1733–1806) extended this work by noting the function of nectar in attracting pollinators and the role of wind and insects in pollination. He also produced deliberate hybrids, observed the microscopic structure of pollen grains and how the transfer of matter from the pollen to the ovary inducing the formation of the embryo. 
+One hundred years after Camerarius, in 1793, Christian Sprengel (1750–1816) broadened the understanding of flowers by describing the role of nectar guides in pollination, the adaptive floral mechanisms used for pollination, and the prevalence of cross-pollination, even though male and female parts are usually together on the same flower.
+Much was learned about plant sexuality by unravelling the reproductive mechanisms of mosses, liverworts and algae. In his Vergleichende Untersuchungen of 1851, Wilhelm Hofmeister (1824–1877) starting with the ferns and bryophytes demonstrated that the process of sexual reproduction in plants entails an "alternation of generations" between sporophytes and gametophytes. This initiated the new field of comparative morphology which, largely through the combined work of William Farlow (1844–1919), Nathanael Pringsheim (1823–1894), Frederick Bower, Eduard Strasburger and others, established that an "alternation of generations" occurs throughout the plant kingdom.
+
+== Nineteenth-century foundations of modern botany ==
+In about the mid-19th century, scientific communication changed. Until this time, ideas were largely exchanged by reading the works of authoritative individuals who dominated in their field: these were often wealthy and influential "gentlemen scientists". Now, research was reported by the publication of "papers" that emanated from research "schools" that promoted the questioning of conventional wisdom. This process had started in the late 18th century when specialist journals began to appear. Even so, botany was greatly stimulated by the appearance of the first "modern" textbook, Matthias Schleiden's (1804–1881) Grundzüge der Wissenschaftlichen Botanik, published in English in 1849 as Principles of Scientific Botany. By 1850, an invigorated organic chemistry had revealed the structure of many plant constituents. Although the great era of plant classification had now passed, the work of description continued. Augustin de Candolle (1778–1841) succeeded Antoine-Laurent de Jussieu in managing the botanical project Prodromus Systematis Naturalis Regni Vegetabilis (1824–1841) which involved 35 authors: it contained all the dicotyledons known in his day, some 58000 species in 161 families, and he doubled the number of recognized plant families, the work being completed by his son Alphonse (1806–1893) in the years from 1841 to 1873.
+
+=== Plant geography and ecology ===

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+The opening of the 19th century was marked by an increase in interest in the connection between climate and plant distribution. Carl Willdenow (1765–1812) examined the connection between seed dispersal and distribution, the nature of plant associations and the impact of geological history. He noticed the similarities between the floras of N America and N Asia, the Cape and Australia, and he explored the ideas of "centre of diversity" and "centre of origin". German Alexander von Humboldt (1769–1859) and Frenchman Aime Bonpland (1773–1858) published a massive and highly influential 30 volume work on their travels; Robert Brown (1773–1852) noted the similarities between the floras of S Africa, Australia and India, while Joakim Schouw (1789–1852) explored more deeply than anyone else the influence on plant distribution of temperature, soil factors, especially soil water, and light, work that was continued by Alphonse de Candolle (1806–1893). Joseph Hooker (1817–1911) pushed the boundaries of floristic studies with his work on Antarctica, India and the Middle East with special attention to endemism. August Grisebach (1814–1879) in Die Vegetation der Erde (1872) examined physiognomy in relation to climate and in America geographic studies were pioneered by Asa Gray (1810–1888).
+Physiological plant geography, or ecology, emerged from floristic biogeography in the late 19th century as environmental influences on plants received greater recognition. Early work in this area was synthesised by Danish professor Eugenius Warming (1841–1924) in his book Plantesamfund (Ecology of Plants, generally taken to mark the beginning of modern ecology) including new ideas on plant communities, their adaptations and environmental influences. This was followed by another grand synthesis, the Pflanzengeographie auf Physiologischer Grundlage of Andreas Schimper (1856–1901) in 1898 (published in English in 1903 as Plant-geography upon a physiological basis translated by W. R. Fischer, Oxford: Clarendon press, 839 pp).
+
+=== Anatomy ===
+
+During the 19th century, German scientists led the way towards a unitary theory of the structure and life-cycle of plants. Following improvements in the microscope at the end of the 18th century, Charles Mirbel (1776–1854) in 1802 published his Traité d'Anatomie et de Physiologie Végétale and Johann Moldenhawer (1766–1827) published Beyträge zur Anatomie der Pflanzen (1812) in which he describes techniques for separating cells from the middle lamella. He identified vascular and parenchymatous tissues, described vascular bundles, observed the cells in the cambium, and interpreted tree rings. He found that stomata were composed of pairs of cells, rather than a single cell with a hole.
+Anatomical studies on the stele were consolidated by Carl Sanio (1832–1891), who described the secondary tissues and meristem including cambium and its action. Hugo von Mohl (1805–1872) summarized work in anatomy leading up to 1850 in Die Vegetabilische Zelle (1851) but this work was later eclipsed by the encyclopaedic comparative anatomy of Heinrich Anton de Bary in 1877. An overview of knowledge of the stele in root and stem was completed by Van Tieghem (1839–1914) and of the meristem by Carl Nägeli (1817–1891). Studies had also begun on the origins of the carpel and flower that continue to the present day.
+
+=== Water relations ===
+
+The riddle of water and nutrient transport through the plant remained. Physiologist Von Mohl explored solute transport and the theory of water uptake by the roots using the concepts of cohesion, transpirational pull, capillarity and root pressure. German dominance in the field of experimental physiology, largely influenced by Wilhelm Knop and Julius von Sachs, was underlined by the publication of the definitive textbook on plant physiology synthesising the work of this period, Sachs' Vorlesungen über Pflanzenphysiologie of 1882. There were, however, some advances elsewhere, such as the early exploration of geotropism (the effect of gravity on growth) by Englishman Thomas Knight, and the discovery and naming of osmosis by Frenchman Henri Dutrochet (1776–1847). The American Dennis Robert Hoagland (1884–1949) discovered the dependence of nutrient absorption and translocation by the plant on metabolic energy.
+
+=== Cytology ===
+
+The cell nucleus was discovered by Robert Brown in 1831. Demonstration of the cellular composition of all organisms, with each cell possessing all the characteristics of life, is attributed to the combined efforts of botanist Matthias Jakob Schleiden and zoologist Theodor Schwann (1810–1882) in the early 19th century, although Moldenhawer had already shown that plants were wholly cellular with each cell having its own wall and Julius von Sachs had shown the continuity protoplasm between cell walls.
+From 1870 to 1880, it became clear that cell nuclei are never formed anew but always derived from the substance of another nucleus. In 1882, Walther Flemming observed the longitudinal splitting of chromosomes in the dividing nucleus and concluded that each daughter nucleus received half of each of the chromosomes of the mother nucleus: then by the early 20th century, it was found that the number of chromosomes in a given species is constant. With genetic continuity confirmed and the finding by Eduard Strasburger that the nuclei of reproductive cells (in pollen and embryo) have a reducing division (halving of chromosomes, now known as meiosis) the field of heredity was opened up. By 1926, Thomas Morgan was able to outline a theory of the gene and its structure and function. The form and function of plastids received similar attention, the association with starch being noted at an early date. 
+Later, the cytological basis of the gene-chromosome theory of heredity extended from about 1900–1944 and was initiated by the rediscovery of Gregor Mendel's (1822–1884) laws of plant heredity first published in 1866 in Experiments on Plant Hybrids and based on cultivated pea Pisum sativum; this heralded the opening up of plant genetics. The cytological basis for gene-chromosome theory was explored through the role of polyploidy and hybridisation in speciation and it was becoming better understood that interbreeding populations were the unit of adaptive change in biology.
+
+=== Developmental morphology and evolution ===

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+
+Until the 1860s, it was believed that species had remained unchanged through time: each biological form was the result of an independent act of creation and therefore absolutely distinct and immutable. But the hard reality of geological formations and strange fossils needed scientific explanation. Charles Darwin's Origin of Species (1859) replaced the assumption of constancy with the theory of descent with modification. Phylogeny became a new principle as "natural" classifications became classifications reflecting, not just similarities, but evolutionary relationships. Wilhelm Hofmeister established that there was a similar pattern of organisation in all plants expressed through the alternation of generations and extensive homology of structures.
+German writer Johann Wolfgang von Goethe (1749–1832), a polymath, had interests and influence that extended into botany. In Die Metamorphose der Pflanzen (1790), he provided a theory of plant morphology (he coined the word "morphology") and he included within his concept of "metamorphosis" modification during evolution, thus linking comparative morphology with phylogeny. Though the botanical basis of his work has been challenged, there is no doubt that he prompted discussion and research on the origin and function of floral parts. His theory probably stimulated the opposing views of German botanists Alexander Braun (1805–1877) and Matthias Schleiden who applied the experimental method to the principles of growth and form that were later extended by Augustin de Candolle (1778–1841).
+
+=== Carbon fixation (photosynthesis) ===
+
+At the start of the 19th century, the idea that plants could synthesize almost all their tissues from atmospheric gases had not yet emerged. The energy component of photosynthesis, the capture and storage of the Sun's radiant energy in carbon bonds (a process on which all life depends) was first elucidated in 1847 by Mayer, but the details of how this was done would take many more years. Chlorophyll was named in 1818 and its chemistry gradually determined, to be finally resolved in the early 20th century. The mechanism of photosynthesis remained a mystery until the mid-19th century when Sachs, in 1862, noted that starch was formed in green cells only in the presence of light, and in 1882, he confirmed carbohydrates as the starting point for all other organic compounds in plants. The connection between the pigment chlorophyll and starch production was finally made in 1864 but tracing the precise biochemical pathway of starch formation did not begin until about 1915.
+
+=== Nitrogen fixation ===
+
+Significant discoveries relating to nitrogen assimilation and metabolism, including ammonification, nitrification and nitrogen fixation (the uptake of atmospheric nitrogen by symbiotic soil microorganisms) had to wait for advances in chemistry and bacteriology in the late 19th century and this was followed in the early 20th century by the elucidation of protein and amino-acid synthesis and their role in plant metabolism. With this knowledge, it was then possible to outline the global nitrogen cycle.
+
+== Twentieth century ==
+
+20th century science grew out of the solid foundations laid by the breadth of vision and detailed experimental observations of the 19th century. A vastly increased research force was now rapidly extending the horizons of botanical knowledge at all levels of plant organisation from molecules to global plant ecology. There was now an awareness of the unity of biological structure and function at the cellular and biochemical levels of organisation. Botanical advance was closely associated with advances in physics and chemistry with the greatest advances in the 20th century mainly relating to the penetration of molecular organisation. However, at the level of plant communities it would take until mid century to consolidate work on ecology and population genetics.
+By 1910, experiments using labelled isotopes were being used to elucidate plant biochemical pathways, to open the line of research leading to gene technology. On a more practical level, research funding was now becoming available from agriculture and industry.
+
+=== Molecules ===
+
+In 1903, chlorophylls a and b were separated by thin layer chromatography then, through the 1920s and 1930s, biochemists, notably Hans Krebs (1900–1981) and Carl (1896–1984) and Gerty Cori (1896–1957) began tracing out the central metabolic pathways of life. Between the 1930s and 1950s, it was determined that ATP, located in mitochondria, was the source of cellular chemical energy and the constituent reactions of photosynthesis were progressively revealed. Then, in 1944, DNA was extracted for the first time. Along with these revelations, there was the discovery of plant hormones or "growth substances", notably auxins, (1934) gibberellins (1934) and cytokinins (1964) and the effects of photoperiodism, the control of plant processes, especially flowering, by the relative lengths of day and night.
+Following the establishment of Mendel's laws, the gene-chromosome theory of heredity was confirmed by the work of August Weismann who identified chromosomes as the hereditary material. Also, in observing the halving of the chromosome number in germ cells he anticipated work to follow on the details of meiosis, the complex process of redistribution of hereditary material that occurs in the germ cells. In the 1920s and 1930s, population genetics combined the theory of evolution with Mendelian genetics to produce the modern synthesis. By the mid-1960s, the molecular basis of metabolism and reproduction was firmly established through the new discipline of molecular biology. Genetic engineering, the insertion of genes into a host cell for cloning, began in the 1970s with the invention of recombinant DNA techniques and its commercial applications applied to agricultural crops followed in the 1990s. There was now the potential to identify organisms by molecular "fingerprinting" and to estimate the times in the past when critical evolutionary changes had occurred through the use of "molecular clocks".
+
+=== Computers, electron microscopes and evolution ===

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+---
+title: "History of botany"
+chunk: 10/10
+source: "https://en.wikipedia.org/wiki/History_of_botany"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:20.683361+00:00"
+instance: "kb-cron"
+---
+
+Increased experimental precision combined with vastly improved scientific instrumentation was opening up exciting new fields. In 1936, Alexander Oparin (1894–1980) demonstrated a possible mechanism for the synthesis of organic matter from inorganic molecules. In the 1960s, it was determined that the Earth's earliest life-forms treated as plants, the cyanobacteria known as stromatolites, dated back some 3.5 billion years.
+Mid-century transmission and scanning electron microscopy presented another level of resolution to the structure of matter, taking anatomy into the new world of "ultrastructure".
+New and revised "phylogenetic" classification systems of the plant kingdom were produced by several botanists, including August Eichler. A massive 23 volume Die natürlichen Pflanzenfamilien was published by Adolf Engler & Karl Prantl over the period 1887 to 1915. Taxonomy based on gross morphology was now being supplemented by using characters revealed by pollen morphology, embryology, anatomy, cytology, serology, macromolecules and more. The introduction of computers facilitated the rapid analysis of large data sets used for numerical taxonomy (also called taximetrics or phenetics). The emphasis on truly natural phylogenies spawned the disciplines of cladistics and phylogenetic systematics. The grand taxonomic synthesis An Integrated System of Classification of Flowering Plants (1981) of American Arthur Cronquist (1919–1992) was superseded when, in 1998, the Angiosperm Phylogeny Group published a phylogeny of flowering plants based on the analysis of DNA sequences using the techniques of the new molecular systematics which was resolving questions concerning the earliest evolutionary branches of the angiosperms (flowering plants). The exact relationship of fungi to plants had for some time been uncertain. Several lines of evidence pointed to fungi being different from plants, animals and bacteria – indeed, more closely related to animals than plants. In the 1980s-90s, molecular analysis revealed an evolutionary divergence of fungi from other organisms about 1 billion years ago – sufficient reason to erect a unique kingdom separate from plants.
+
+=== Biogeography and ecology ===
+
+The publication of Alfred Wegener's (1880–1930) theory of continental drift 1912 gave additional impetus to comparative physiology and the study of biogeography while ecology in the 1930s contributed the important ideas of plant community, succession, community change, and energy flows. From 1940 to 1950, ecology matured to become an independent discipline as Eugene Odum (1913–2002) formulated many of the concepts of ecosystem ecology, emphasising relationships between groups of organisms (especially material and energy relationships) as key factors in the field. Building on the extensive earlier work of Alphonse de Candolle, Nikolai Vavilov (1887–1943) from 1914 to 1940 produced accounts of the geography, centres of origin, and evolutionary history of economic plants.
+
+== See also ==
+
+== References ==
+
+== Bibliography ==

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+---
+title: "History of business architecture"
+chunk: 1/4
+source: "https://en.wikipedia.org/wiki/History_of_business_architecture"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:15.010771+00:00"
+instance: "kb-cron"
+---
+
+The history of business architecture has its origins in the 1980s. In the next decades business architecture has developed into a discipline of "cross-organizational design of the business as a whole" closely related to enterprise architecture. The concept of business architecture has been proposed as a blueprint of the enterprise, as a business strategy, and also as the representation of a business design.
+The concept of business architecture has evolved over the years. It was introduced in the 1980s as architectural domains and as an activity of business design. In the 2000s the study and concept development of business architecture accelerated. By the end of the 2000s the first handbooks on business architecture were published, separate frameworks for business architecture were being developed, separate views and models for business architecture were further under construction, the business architect as a profession evolved, and more businesses added business architecture to their agenda.
+By 2015 business architecture has evolved into a common practice. The business architecture body of knowledge has been developed and is updated multiple times each year, and the interest from the academic world and from top management is growing.
+
+== Overview ==
+Business architecture has its roots in traditional cross-organizational design. Bodine and Hilty (2009) stipulated, that the "responsibility for the cross-organizational design of the business as a whole, the work of the Business Architect, has historically fallen to the CEO or their assignee, supported by generalist management consulting firms whose teams of MBAs work with corporate managers to transform strategy into new business configurations using the newest tools." John Zachman (2012) commented in this context, that "a lot of material has been written about business architecture (by some definition), going back to The Principles of Scientific Management (1911) by Frederick Taylor."
+One of the roots of business architecture lies in the proposals for enterprise architecture made since the 1980s and 1990s. Bernus & Noran (2010) distinguished two types of proposals. On the one hand "Proposals that created generally applicable ‘blueprints’ (later to be called reference models, partial models...) so that the activities involved in the creation (or the change) of the enterprise could refer to such a common model (or set of models)." And on the other hand "proposals which claimed that to be able to organise the creation, and later the change, of enterprises one needs to understand the life cycle of the enterprise and of its parts... the ‘Enterprise Reference Architecture’."
+More specific about the emerge of business architecture Whelan & Meaden (2012) described, that this emerged against a backdrop of change. The business architecture is "maturing into a discipline in its own right, rising from the pool of inter-related practices that include business strategy, enterprise architecture, business portfolio planning and change management – to name but a few.
+
+== 1980s ==
+
+=== Concept ===
+The concept of business architecture emerged in the 1980s in the field of information systems development. One of the first to mention business architecture was the British management consultant Edwin E. Tozer in the 1986 article "Developing strategies for management information systems." He introduced the concept of business architecture in the context of business information systems planning, and distinguished:
+
+Business architecture, and
+Information architecture,
+And he explained, that "each entity class in the Information Architecture is represented in some database and each business function may be supported by one or more systems." In this paper Tozer was "prescriptive about the order in which [strategy] issues should be identified.", and focussed on "IS adaptability to organizational strategies."
+
+=== First models ===
+The American organizational theorist William R. Synnott (1987) presented one of the first models of business architecture, (see image), in the context of data management. Synnott wanted to develop an overall Information Resource Management (IRM) architecture, and proposed business architecture as its foundation. He described: 
+
+Business architecture is the foundation upon which the IRM architecture rests. The architectural model consists of a set of building-blocks of linked architectures which together form the basis for the technology infrastructure of the firm... In the figure data architecture and communication architecture are shown as horizontal bars because these are corporate-wide information resource components. They serve all business units. The four vertical resource components are business specific. The resources can be divided according to the business units they serve. That us, data and communication might be centralizes resources, whereas human resources (professional systems staffs), computers, user-computing, and systems could all be decentralized resources to one degree or another.
+This model of Information Resource Management (IRM) distinguished seven types of architecture: 
+
+Centralized: Business architecture, Data architecture, and Communication architecture
+Decentralized : Human resources architecture, Computer architecture, User-computing architecture, and Systems architecture.
+This type of architectural model classifies different types of architecture. In the later theories and models different sets of architectures have been proposed. For example, the late 1980s NIST Enterprise Architecture Model distinguished five types, and this was incorporated in the 1990s Federal Enterprise Architecture, which contained four types of architecture.
+
+=== Base for the total development process ===
+Synnott (1987) furthermore described, how business architecture should work and introduced the idea of architectural planning:

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+title: "History of business architecture"
+chunk: 2/4
+source: "https://en.wikipedia.org/wiki/History_of_business_architecture"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:15.010771+00:00"
+instance: "kb-cron"
+---
+
+The business architecture of the company (organization structure, strategic business units and missions, product and services) is the foundation of IRM planning. Since every company has an existing architecture, architectural planning begins with an inventory of the firm's information resources. Assembling the various information resource components' inventories results in an "as is" picture of the corporation's technology structure. From this inventory, the CIO can analyze the strengths and weaknesses of the company's information resources, particularly as they relate to business information needs as identified in the strategic planning process. From this analysis one can evolve an architectural plan, which is a "to be" picture of where one wants to go and how to get there, not just a picture of the status quo.
+Cees J. Schrama. (1988) of the European IFIP Technical Committee on Information Systems IFIP TC8 presented the opinion, that "business architecture is required to provide a solid base for the total development process." He pictured another model consisted of elements such as information processing architecture and network architecture, and explained:
+
+[Business architecture] contains the fundamentals for the information processing architecture, where process data, support systems and network architecture are performed. In business architecture the following can 'be identified:
+- enterprise analysis: to indicate the business domains
+- business analysis
+- Information systems planning
+There are some basic elements in business architecture: management, organization, processes to be performed and data to be made available/delivered. In the past, when mainly operational systems were developed, the processes received considerable attention. Information was seen as being needed to perform processes. This is changing. It is becoming important to have data available to serve information retrieval needs as well.
+These ideas around the concept of architectural planning evolved in the early 1990s into frameworks, such as TAFIM, the predecessor of TOGAF.
+
+=== View models of enterprise architecture ===
+In the 1987 article "A Framework for Information Systems Architecture" John Zachman presented some of the principles of Enterprise architecture,
+
+=== Framework for information systems architecture ===
+
+In the 5th NIST workshop on Information Management Directions (1989) a working groups under guidance of W. Bradford Rigdon developed one of the first Enterprise Architecture frameworks, the NIST Enterprise Architecture Model. In this model business architecture was incorporated as one of the layers of Enterprise Architecture. Bradford Rigdon et al. (1989) brought it like this:
+
+A discussion of architecture must take into account different levels of architecture. These levels can be illustrated by a pyramid, with the business unit at the top and the delivery system at the base. An enterprise is composed of one or more Business Units that are responsible for a specific business area. The five levels of architecture are
+Business Unit
+Information
+Information System
+Data
+Delivery System
+The levels are separate yet interrelated... The idea if an enterprise architecture reflects an awareness that the levels are logically connected and that a depiction at one level assumes or dictates that architectures at the higher level.
+In the original 1989 illustration of the NIST AE Framework (see image) the top layer was named "Business Unit Architecture." In representation of this model in the 1990s the top layer was named "Business architecture."
+
+== 1990s ==
+
+=== The unfolding Information Age ===
+In the 1990s the Information Age was unfolding changing the global market economy. With the businesses adapting, the new concept of business architecture was presented as promising alternative. Gharajedaghi (1999) explained the context:
+
+In a global market economy with ever-increasing levels of disturbance, a viable business can no longer be locked into a single form or function. Success comes from a self-renewing capability to spontaneously create structures and functions that fit the moment. In this context, proper functioning of self-reference would certainly prevent the vacillations and the random search for new products/markets that have, over the past years, destroyed so many businesses.In fact, the ability to continuously match the portfolio of internal competencies with the portfolio of emerging market opportunities is the foundation of the emerging concept of new business architecture...
+According to Bodine and Hilty (2009) "important advances in this area borrowed from the operations discipline came in 1993 in the form of Michael Hammer and James Champy‘s book Reengineering the Corporation, which introduced tools for mapping and optimizing business activities using process modeling. The Balanced Scorecard developed by Robert Kaplan and David Norton at about the same time enabled the business to measure overall corporate success against goals on qualitative as well as quantitative dimensions."
+
+=== Descriptions ===
+In the 1990s works the concept of business architecture is presented in distinguished ways: 

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+title: "History of business architecture"
+chunk: 3/4
+source: "https://en.wikipedia.org/wiki/History_of_business_architecture"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:15.010771+00:00"
+instance: "kb-cron"
+---
+
+As activity : Lindsay & Price (1991) for example presented business architecture as a "self security activity," which included the "study of a function, including its component organizations, tools, methods, and relationships, both internal and external... The very activity of identifying and listing all these elements is an important learning process for managers. In addition to the element identification and listing processes, the architecture develops a set of principles. Principles are semi-permanent statements of philosophy. That is, they are the basic rules by which managers agree they want to operate."
+As blueprint or model of the enterprise : Bourke (1994) described it as "a set of integrated blueprints of the ... [enterprise]'s business processes," and Veasey (1994) spoke of business architecture as "a model of the enterprise which is a mechanism for the management of change."
+As strategy for any change program : Davis (1996) for example described that business architecture can be used to "describe the type of comprehensive plan required to set the stage for integrated change programmes. The term "architecture" connotes the level of creativity and holistic change required to achieve process excellence. A comprehensive business architecture defines the way in which human performance, processes and technology will be integrated to transform business performance and create value."
+Business architectures is presented as tool for change management, acknowledged Van Rensburg (1997). It "provide organisations with the means to understand organisational activities in such a manner that it is used as a mechanism to support the organisation through the business transformation process. Using an object-oriented modelling approach in the design of the business architecture allows for a robust modelling approach which captures real world instances in a business architecture repository. This enables the creation and caption of organisational understanding required for the transformation process."
+
+=== FEA and business subarchitecture ===
+In 1996 the US government introduced the Clinger–Cohen Act, to improve the acquisition and management of their information resources.
+
+=== Enterprise reference architecture ===
+Beside the enterprise architecture frameworks a second type of architectural models were proposed in the late 1980s and early 1990s, which were called Enterprise Reference Architecture. 
+
+GRAI-GIM (Doumeingts, 1987)
+PERA (Williams 1994)
+CIMOSA (CIMOSA Association 1996),
+Architecture of Integrated Information Systems (Scheer 1999), and
+GERAM (IFIP-IFAC Task Force, 1999)
+
+=== Foundation ===
+In 1999 two works on business architecture and its foundation were published, which became two of the most cited works on business architecture. In his "Systems thinking: Managing chaos and complexity" Jamshid Gharajedaghi presented a set of principles to design business architecture, which were based on systems thinking. Gharajedaghi argued, that business Architecture should be considered a system:
+
+Business Architecture is a general description of a system. It identifies its purpose, vital functions, active elements, and critical processes and defines the nature of the interaction among them. Business architecture consists of a set of distinct but interrelated platforms, creating a multidimensional modular system. Each platform represents a dimension of the system, signifying a unique mode of behavior with a predefined set of performance criteria and measures.
+The IBM researcher Douglas W. McDavid presented the paper "A standard for business architecture description." According to Evernden & Evernden (2003) this paper described a "high-level semantic framework of standard business concepts – abstracted from experience, enterprise business models, the organization of business terminology and the various generic industry reference models. There is an excellent discussion on what constitutes business architecture and the nature and use of information categories, although concepts such as product and agreement seem to be missing." McDavid argued:
+
+The concepts in the Business Architecture description provide a semantic framework for speaking about common business concerns... For our purposes, this semantic structure provides a common set of concept patterns to be able to understand the types of content that needs to be supported in technology-based information systems... a set of generic concepts and their interrelationships organize business information content in terms of requirements on the business, the boundary of the business, and the business as a system for delivery of value.
+
+== 2000s ==
+
+ NOTE: This Framework draws heavily from BusinessGenetics Business Modelling Language (BML)
+
+=== Business architect ===
+According to Bodine and Hilty (2009)
+
+The arrival of Internet technologies like email, instant messaging and online data repositories in the mid-1990s opened up tremendous flexibilities in the ways co-workers could collaborate, while the new ability of buyers and sellers to interact in virtual space and transact online changed the traditional structure of businesses...
+By the late 1990s, MBAs with advanced skills in Internet technologies began developing live business models for e-commerce websites in real-time. They used the development tools to both represent and build the business at the same time. The model became the business, and thousands were launched, allowing companies to access vast volumes of data and respond rapidly to changing market conditions... A Google search on ―Business Architect‖ at the time returned just 12 results... A Google search on ―Business Architect‖ in 2009 returns over 1 million listings.
+
+This is just the beginning of a valuable and rapidly expanding profession. Today‘s Business Architects take a holistic view of the complete business representing all interests and engaging all expertise. They see the business organization as a constantly changing, dynamic organism that balances central planning with individual initiative to achieve its mission through the articulate implementation of its corporate strategy.
+
+=== Tools and frameworks ===
+According to Bodine and Hilty (2009)
+
+Important advances in this area borrowed from the operations discipline came in 1993 in the form of Michael Hammer and James Champy‘s book Reengineering the Corporation, which introduced tools for mapping and optimizing business activities using process modeling. The Balanced Scorecard developed by Robert Kaplan and David Norton at about the same time enabled the business to measure overall corporate success against goals on qualitative as well as quantitative dimensions.
+According to Bernus & Noran (2010):

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+title: "History of business architecture"
+chunk: 4/4
+source: "https://en.wikipedia.org/wiki/History_of_business_architecture"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:15.010771+00:00"
+instance: "kb-cron"
+---
+
+Architecture Frameworks have been used in many industries, including the domains of industrial automation / manufacturing / production management, business information systems (of various kinds), telecommunications and defence. Part of the Enterprise Architecture practice is ‘enterprise engineering’ and the practice of ‘enterprise modelling’ (or just modelling) and complete AFs describe the scope of modelling (which later can be summaised as a Modelling Framework that is part of the AF).
+One specific type of Framework is called the "Enterprise Reference Architecture." According to Bernus & Noran (2010):
+
+Several proposals emerged in those two decades – e.g. PERA (Williams 1994), CIMOSA (CIMOSA Association 1996), ARIS (Scheer 1999), GRAI-GIM (Doumeingts, 1987), and the IFIP-IFAC Task Force, based on a thorough review of these as well as their proposed generalisation (Bernus and Nemes, 1994) developed GERAM (IFIP-IFAC Task Force, 1999) which then became the basis of ISO15704:2000 “Industrial automation systems – Requirements for enterprise-reference architectures and methodologies”...
+
+=== Business Architecture Working Group ===
+
+The Business Architecture Special Interest Group (BASIG) is a working group on business architecture of the Object Management Group (OMG). This working group was founded in 2007 as the Business Architecture Working Group (BAWG).
+
+=== Business strategy ===
+In the 2006 article "Business Architecture: A new paradigm to relate business strategy to ICT," Versteeg & Bouwman explained the relation between business architecture, business activities and business strategy. They wrote:
+
+We use the concept of 'Business Architecture’ to structure the responsibility over business activities prior to any further effort to structure individual aspects (processes, data, functions, organization, etc.). The business architecture arranges the responsibilities around the most important business activities (for instance production, distribution, marketing, et cetera) and/or economic activities (for instance manufacturing, assembly, transport, wholesale, et cetera) into domains 
+Versteeg & Bouwman also stipulated, that "the perspectives for subsequent design next to organization are more common: information architecture, technical architecture, process architecture. The various parts (functions, concepts and processes) of the business architecture act as a compulsory starting point for the different subsequent architectures. It pre-structures other architectures. Business architecture models shed light on the scantly elaborated relationships between business strategy and business design. We will illustrate the value of business architecture in a case study."
+
+== 2010s ==
+
+=== Handbooks ===
+In the 2010 the first handbooks on Business architecture were published. In the US William M. Ulrich and Neal McWhorter of the OMG Business Architecture Special Interest Group published the "Business Architecture: The Art and Practice of Business Transformation," in 2010.
+In 2012 in Britain the business consultants Jonathan Whelan and Graham Meaden published their "Business Architecture: A Practical Guide."
+
+=== Definition ===
+In several sources in the exact definition of "business architecture" is under review. In 2008 Jeff Scott had commented in this matter: 
+
+Interest in business architecture is growing dramatically. During the past two years both IT and business leaders have joined the discussion about the need for a well-defined business architecture. Though there is a great deal of discussion, there is little consensus about what business architecture is, how it should be pursued, and what value it delivers. Business architects in IT as well as in the business have started developing business-unit-wide and enterprise-wide business architectures, learning as they go. Their ultimate goals are to improve business decision-making and facilitate better alignment between IT and the business units it supports. Architecture teams that want to play a leading role in business architecture development must start soon or be left behind.
+Other sources came to the same conclusion, that over the years many different definitions of business architecture have been proposed Some of the more notable definitions have described business architecture as: 
+
+"A blueprint of the enterprise that provides a common understanding of the organization and is used to align strategic objectives and tactical demands" - OMG Business Architecture Working Group, 2008
+"The business strategy, governance, organization, and key business processes information, as well as the interaction between these concepts." - TOGAF, 2009
+"The formal representation and active management of business design." - SOA Consortium, EA2010 Working group on Business Architecture, 2010
+The discussion kept going. John Zachman (2012) declared in this matter, that "a lot of people define business architecture differently (I know a lot of people who have a lot of different opinions and definitions for business architecture). Not too many people do business architecture, at least not in a comprehensive and definitive fashion (in my estimation)..." 
+
+== Roots in various academic domains ==
+Ideas and definitions about business architecture originate from different academic sub disciplines, where the concept of business architecture and methods and techniques are developing in numerous initiatives. A selection of related subfields:
+
+Organizational theory inspired by systems thinking, cybernetics, complexity science, etc.
+Systems analysis and design, system engineering, business engineering, business modeling, business process modeling, business process management, business process reengineering etc.
+Software engineering, information engineering, information technology management, etc.
+Enterprise architecture, enterprise engineering, enterprise modeling, enterprise ontology, enterprise resource planning, etc.
+
+== Field of practice ==
+Guitarte (2013) stipulated, that also different types of organizations have been active, and created a so-called "business architecture vortex.” He listed four types:
+
+Influencers: Academe, Various authors, Cutter, Forrester, Media, Gartner, IIR
+Third-party vendors: Metastorm, IBM, Sparx, Troux, Mega, BrainstormCentral, Pega, BAI, BPMI, Progress
+Communities of practice: Business Architecture Guild, Business Architecture Society, BAA, BizArchCommunity, BAA, IIBA, PMI, AOGEA
+Standards-setting bodies: ISO, BPMN, OMG, MDA, BASIG, The Open Group, TOGAF, BPM/SOA, BEI
+Guitarte commented, that "influencers led followed by communities of practice and standards-setting bodies; vendors followed. Conflicting ideas provide opportunity to define the future of business architecture profession."
+
+== Management interests ==
+Surveys have reported a growing interest of management in business architecture, as well as on universities:
+
+In 2004 Jaap Schekkerman already suggested that "Enterprise Architecture was ranked near the top of the list of most important issues considered by CEO’s and CIO’s."
+
+== References ==
+
+== Further reading ==
+Gharajedaghi, Jamshid. Systems thinking: Managing chaos and complexity: A platform for designing business architecture. Elsevier, 1999; 2nd ed. 2005; 3rd ed. 2011
+Susanne Glissman, and Jorge Sanz. "A comparative review of business architecture." IBM Research Report,2009.
+William M. Ulrich, Neal McWhorter, Business Architecture: The Art and Practice of Business Transformation, Meghan-Kiffer Press, 2010;
+Jonathan Whelan, Graham Meaden. Business Architecture: A Practical Guide. 2012.
+Ralph Whittle, Conrad B. Myrick. Enterprise Business Architecture: The Formal Link between Strategy and Results, 2004
+
+== External links ==
+ Media related to Business architecture at Wikimedia Commons
+ Quotations related to Enterprise architecture at Wikiquote

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+---
+
+Youth services is a field of practices within the social services sector in North America. Defined as "programs, activities, and services aimed at providing a range of opportunities for school-aged children, including mentoring, recreation, education, training, community service, or supervision in a safe environment," youth services are a comprehensive series of strategies, activities, programs and organizations spread across the United States and Canada today. In North America, youth services are generally viewed as more organized and systemized than youth work. The term "youth services" is used in international contexts as well.
+
+
+== Activities ==
+Youth services are varied and disparate, often emerging from the needs of their local context or from the mandate of external funding sources. "Best practices in youth services include the provision of safety, appropriate supervision, supportive relationships, opportunities to belong, positive social norms, support for efficacy and skill building, and integration of community, school, and family efforts."
+Specific activities, projects, programs and organizations within the realm of youth services address a variety of issues. According to Fletcher (2024), they include: 
+
+Prevention
+Intervention
+Out-of-school time education
+Personal identities
+Civics and democracy
+Culture and society
+Rights and freedoms
+Youth-specific issues
+Public health
+Personal health (including mental health)
+The economy
+Crisis support
+Nature and the outdoors
+Recreation
+The arts
+Personal development
+Empowerment
+Within each of those categories are more specific practices. For instance, the practice of "youth services librarianship" "encompasses all library services to youth (children and young adults, ages zero to eighteen) in school and public library settings." According to one author, it "has long been considered the classic success story of American libraries."
+
+
+== Funding and support ==
+There are various sources of funding for youth services across North America. They include government and philanthropic foundations, as well as corporate and private donors. In the U.S., the current thrust of youth services emphasizes positive youth development. In Contra Costa County, youth services "receives funding from the California Department of Education, the Contra Costa County Workforce Development Board, Contra Costa County Employment and Human Services, the Department of Rehabilitation, as well as other funding sources."
+In addition to local variations, there has been a wide variety of political, fiscal and public support for youth services throughout time. For instance, the New York City Youth Board existed from 1947 until 1976 "when most of the program services were redistributed to several other city agencies." From that dispersion, many activities, projects and services were defunded and forgotten about for several years.
+
+
+=== U.S. federal support ===
+The U.S. federal government supports a variety of youth services. For instance, the United States Department of Labor houses the Employment and Training Administration Division of Youth Services. This division "primarily serve[s] young adults ages 16-24 that face a variety of barriers to employment. We provide leadership to the workforce system and our grantees, policy direction and guidance, support for program administration, and technical assistance." Some of their youth services programs include Workforce Innovation and Opportunity Act Youth Formula, YouthBuild, and Reentry Employment Opportunities.
+The United States Department of Health & Human Services Office of the Administration for Children & Families extensively addresses youth services. Many issues are served by this agency, including:
+
+Adolescent pregnancy prevention: These services "educate adolescents on both abstinence and contraception for the prevention of pregnancy and sexually transmitted infections... and exclusively implement[s] sexual risk avoidance education that teaches youth how to voluntarily refrain from non-marital sexual activity, empower youth to make healthy decisions, and provide tools and resources to prevent youth engagement in other risky behaviors."
+Runaway and homeless youth: These programs "serve and protect runaway and homeless youth" through street outreach, transitional living skills education, and maternity group homes" for youth.
+Foster care and successful transitions to adulthood: The agency "provides funding to support youth and young adults in or formerly in foster care in their transition to adulthood."
+Unaccompanied refugee minors programs: "Services provided include arranging foster care, group homes, independent living situations, or reunification with relatives in the U.S., as well as other child welfare services to promote their well-being." The agency also researches and evaluates each of these program areas.
+
+
+=== U.S. state support ===
+Similarly, many U.S. states, counties and local municipalities support youth services as well. In Utah, the Department of Health and Human Services houses a division called juvenile justice and youth services whose goal is to "prevent delinquent behaviors through positive youth and family development." The stated goals of this division include, "Keep[ing] youth safely in their homes, schools and communities; Early screening of a youth and family strength and needs; Connect youth and families to appropriate services in the community." In Massachusetts, the Massachusetts Department of Youth Services is the "Juvenile Justice agency for the Commonwealth of Massachusetts" and "promotes positive change in the youth in our care and custody." In Illinois, the Department of Human Services Office of Community and Positive Youth Development offers youth services for "youth who are in trouble with the legal system" and "runaways/lock-outs/homeless youth," as well as for youth employment, teen pregnancy prevention, substance abuse prevention, community initiatives, and other areas.
+
+
+=== U.S. county support ===
+In Yamhill County, Oregon, the county government has a youth services division that focuses on children and youths' mental health, with their website stating they provide "an array of mental health professionals who have advanced education and training in counseling and various specialties. Our approach matches the best practices developed by research and national experts. We focus on helping children, teens and parents improve skills, health and well-being." Youth services offered by Contra Costa County, California are offered by the county's Office of Education and include "provides a broad range of coordinated services for youth who are in foster care, experiencing homelessness or other barriers and need support to finish school, find a job or pursue a career path." The Baltimore County, Maryland government "Youth Services Unit provides support for programs that engage eligible young people between the ages of 14 and 24 who are in school, have graduated or dropped out of high school, by providing valuable education, training, counseling and work-based learning opportunities."
+
+
+== History of the field ==
+Having started in the 1860s, the Commonwealth of Massachusetts counts their youth services as the "first in the nation." A comprehensive timeline from the University of North Carolina shows that library youth services began in the 17th century.
+
+
+== Criticism ==
+Critical perspectives of youth services are as broad as the number of practices throughout the field. For instance, Anthony Bernier, a professor at San Jose State University, wrote "The overarching assessment of youth services rendered by Leslie Edmonds in 1987 remains largely true today: that its most influential force remains not research, or evidence, or constant professional improvement or addressing field-based challenges, but 'superstition.'"
+There are also concerns about continuity of care in youth services, "aging out" (the process of becoming an adult), the effects of austerity of the field, among others.
+
+
+== See also ==
+Family and Youth Services Bureau
+Children and Youth Services Review
+List of youth organizations
+Sequel Youth and Family Services
+National Council for Voluntary Youth Services
+Ohio Department of Youth Services
+Youth intervention
+
+
+== References ==

data/en.wikipedia.org/wiki/Youth_studies-0.md

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+---
+title: "Youth studies"
+chunk: 1/1
+source: "https://en.wikipedia.org/wiki/Youth_studies"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:09.539425+00:00"
+instance: "kb-cron"
+---
+
+Youth studies is an interdisciplinary academic field devoted to the study of the development, history, culture, psychology, and politics of youth. The field studies not only specific cultures of young people, but also their relationships, roles and responsibilities throughout the larger societies which they occupy. The field includes scholars of education, literature, history, politics, religion, sociology, and many other disciplines within the humanities and social sciences. Youth studies encourages the understanding of experiences that are predominantly manifested among young people, generalized phenomenon and social change. The majority of 15- to 24-year-olds in 2008 lived in developing countries.  The definition of youth varies across cultural contexts. The social experience and organization of time and space are important themes in youth studies.  Scholars examine how neoliberalism and globalization affect how young people experience life, including in comparison to previous generations.
+
+
+== Topics ==
+Youth voice
+Youth development
+History of youth (category)
+Youth culture
+Psychology
+Youth politics
+Children's geographies
+Youth empowerment
+Youth rights
+Civic engagement
+Youth participation
+Criminalization
+Youth service
+Youth courts
+Youth work
+Adultism
+Adultcentrism
+Ephebiphobia
+
+
+== Scholarly and academic journals ==
+International Journal of Child, Youth & Family Studies.
+Journal of Youth Studies
+Youth Studies Australia
+Vulnerable Children and Youth Studies
+Journal of Early Adolescence, ISSN 1552-5449 (electronic) ISSN 0272-4316 (paper) 
+
+
+== See also ==
+August Aichhorn
+Australian Clearinghouse for Youth Studies
+Child abuse
+CommonAction
+Forum for Youth Investment
+List of youth topics
+Sociology of the family
+The Wave Trust
+Adolescent suicide
+
+
+== References ==
+
+
+== Bibliography ==
+Bassani, C. (2007) "Five Dimensions of Social Capital Theory as They Pertain to Youth Studies." Journal of Youth Studies, 10 (1) February 2007, pages 17–34.
+Tsekeris, C. and Stylianoudi, L. (2017) "Youngsters and Adolescents in Troubled Contexts: Worldwide Perspectives." Contemporary Social Science: Journal of the Academy of Social Sciences, 12 (3–4) December 2017, pages 165–174.
+
+
+== External links ==
+Youth Studies Research Guide. RMIT (Australia).
+Center for Youth Studies - A religious organization (U.S.).
+Youth Studies at the School of Social Work, University of Minnesota (U.S.).
+Australian Clearinghouse for Youth Studies.
+Children and Youth Studies major. Open College (U.K.).
+Carnegie Young People Initiative. (U.K.)
+CYFERNet: Children, Youth and Families Education and Research Network. (U.S.).
+Department of Child and Youth Studies at Brock University (Canada).
+Children and Youth Studies Caucus, American Studies Association, Georgetown University.
+Youth Studies Certification Program. CUNY. (U.S.)
+Youth Studies Net Archived 2007-07-05 at the Wayback Machine, City University of Hong Kong.
+Child and Youth Studies Institute Association of African Universities (Senegal).

data/en.wikipedia.org/wiki/Zemiology-0.md

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+---
+title: "Zemiology"
+chunk: 1/3
+source: "https://en.wikipedia.org/wiki/Zemiology"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:10.811479+00:00"
+instance: "kb-cron"
+---
+
+Zemiology is the study of social harms. Zemiology gets its name from the Greek word ζημία zēmía, meaning "harm".
+It originated as a critique of criminology and the notion of crime. In contrast with "individual-based harms" such as theft, the notion of social harm or social injury incorporates harms caused by nation states and corporations. These ideas have received increased attention from critical academics such as neo-Marxists and feminists who have sought to create an independent field of study, separate from criminology. Zemiology studies the harms that affect individuals' lives that are not considered to be criminal or are rarely criminalised, such as mortgage misselling, poverty and unemployment.
+
+== Zemiological critique of criminology and crime ==
+Hillyard and Tombs outline a number of criticisms of criminology and crime:
+
+"Crime has no ontological reality" – Crime is a construct and is based on social judgements. However, there are no central properties that pertain to the notion of crime; therefore, what is a crime will vary across time and space.
+"Criminology perpetuates the myth of crime" – Criminology is based upon the notion of crime, which fails to adequately address the social construction of the concept. Therefore, criminology's continued use of the notion within its frame of analysis perpetuates the myth that crimes are distinct acts that may be understood as separate social phenomena.
+"Crime consists of many petty events" – In a large proportion of reported crimes, the harms endured by victims, if there are any, are minimal. Hence Hillyard and Tombs argue that "the definitions of crime in the criminal law do not reflect the only or the most dangerous of antisocial behaviours."
+"Crime excludes many serious harms" – Many events and incidents which cause serious harm are either not part of the criminal law or, if they could be dealt with by it, are either ignored or handled without resort to it. The undue attention given to events which are defined as crimes distracts attention from more serious harm (such as pollution or poverty).
+"'Crime control' is ineffective" – Hillyard and Tombs have argued that the methods and approach to crime control have patently failed. They believe the criminal justice system is unsuccessful in fulfilling its aims and in reforming criminal offenders. It appears that the criminal justice system sees there is only one solution to crime control, and that is a prison sentence; however, it is questionable whether this actually resolves certain crimes in society.
+"'Crime' gives legitimacy to the expansion of crime control" – Since the early 1990s, governments have emphasised crime control as a key concern, and crime control has increased faster than any other area of public expenditure. Consequently, security firms have increasingly sought to provide services to the burgeoning penal state. It is argued that these private interests have played a key part in the expansion of prison, as means to deal with social problems.
+"Contrasting 'crimes'" – The criminal law uses different tests to determine whether a crime has been committed. The principal test is the concept of mens rea – the guilty mind – which applies to the individual but not exclusively. However, these tests are not objective and often rely on subjective judgements about an individual's actions. Mens rea has to be judged by proxy, examining both a person's words and deeds. This becomes an even more complex task when applying the test an organisation, particularly as the harms caused by organisations result from the actions or inactions of a number of individuals and omission rather than intent. Therefore, harms caused by organisations are rarely criminalised.
+
+== Harms of the criminal justice system ==
+Hillyard and Tombs argue that the criminal justice system fails to protect people from criminal harms whilst inflicting serious harms on those people who travel through the system. These harms often outweigh the harm caused by the original crime. However, current criminal justice policy within countries like the UK continues to champion the use of prison as a means to deal with social problems. In 2002, the UK prison population was 80,144. The population rate, per hundred thousand of national population, for England and Wales was 139. These figures are high compared to the rest of Europe in terms of overall numbers; however, looking at prison population rate, they are similar to many other countries in Europe. Italy, Spain, France, Romania and Belarus each had prison populations of around 50,000 in 2001–2002. Only Poland and Ukraine had prison populations higher than that of the UK, at 82,173 and 198,885 respectively.
+These rising prison numbers however do not necessarily reflect a rise in crime. Overall, since 1995 there has been a reduction in recorded crime. The British Crime Survey has shown that the overall crime experienced by households has declined by 42% which is the equivalent to eight million fewer crimes. More specifically, domestic burglary has fallen by 59%, vehicle theft has decreased by 61% and violent crimes have experienced a reduction of 41%. According to these figures it appears that the reason for the growth in the prison population is not due to a rise in crime.
+In spite of the faith demonstrated by politicians in the criminal justice system, it would appear that the criminal justice system seems to fail in its own terms. The probability of a criminal re-offending is determined by external factors including having a stable family life, a home and a job. All of these are arguably weakened by a prison sentence. The Social Exclusion Unit has demonstrated that prison fails to rehabilitate on a dramatic scale with two thirds of prisoners re-offending within two years of release. However, a prison place costs £37,000 per annum.

data/en.wikipedia.org/wiki/Zemiology-1.md

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+---
+title: "Zemiology"
+chunk: 2/3
+source: "https://en.wikipedia.org/wiki/Zemiology"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:10.811479+00:00"
+instance: "kb-cron"
+---
+
+=== Relation of welfare benefits to prison population ===
+Concern has been expressed that the prison is being used as a mechanism to deal with social problems as spending on welfare benefits and services has decreased. Downes and Hansen argue that a country's welfare spending and prison population are inversely related, meaning that a country with high spending on welfare has a lower prison population and vice versa. Portugal, for example, has 147 prisoners per 100,000 people but spend only 18.2% of their GDP on welfare. This is quite a contrast to Scandinavian states, such as Sweden, whose prison population is 60 prisoners per 100,000 people as they spend 31% of GDP on welfare. During the 1990s the UK, whose spending on welfare is 20.8% GDP, saw an increase of 40% in the number of custodial sentences passed out. This is arguably reflected in the composition of the UK's prison population. For example, almost half of the prison population in Britain has been diagnosed with 3 or more mental disorders. Of those prisoners diagnosed with a mental health problem: 50% of these prisoners are not registered with a GP; 42% of men with a psychotic disorder received no emotional or mental support in the previous year before imprisonment; 79% of men with a personality disorder received no emotional or mental support in the previous year before imprisonment; 46% have been arrested having never received any benefits despite their disorder; over a third are sleeping rough and over two thirds are not in education or training.
+
+== Broadening perceptions of harm ==
+
+=== Physical harm ===
+The zemiological or social harm approach attempts to broaden public and sociological focus to vicissitudes of daily life in capitalist society; some of these harms, they argue, are more harmful than those caused by crime. Approximately 1,000 people a year are murdered in England and Wales. However, there are a number of events that cause large amounts of physical harm and even death, which are rarely considered crime or criminalised. In the UK there are around 40,000 serious road accidents in the UK every year. This is equivalent to a jumbo jet crashing every month. In 2002 3,431 people were killed on Britain's roads and 35,976 seriously injured. In 2002, 81,562 cases of food poisoning were reported and the majority of these cases are believed to have been contracted in food prepared outside the home. In the UK, The Labour Force Survey found that 228 people were killed while working due to a work-related incident and 2.2 million people with illnesses in the UK believed their condition was made worse by their past or current job. A growing phenomenon affecting workers' health is stress. A report issued by the British Health and Safety Executive found that 16% of workers were working over 60 hours a week. Similarly, the Department of Trade and Industry found that 19% of men visited doctors for stress related problems, with that figure rising to 23% in men over 40. Also, the Trades Union Congress found 10% of work-based personal injury cases were stress-related. According to the Department of Health there were 3500 deaths occurring from the effects of sulphur dioxide and 8100 deaths were caused due to particulate matter in the air in July 2002.
+
+=== Homeowners ===
+Equally, the financial costs theft and burglary are outweighed when one considers wider financial harms. For example, thousands of homeowners have been sold endowment mortgages without any likely means of repaying them. More than 3 million homeowners face the likelihood that their endowment policy, when it matures, will be worth too little to pay off the mortgage. 60% of endowment mortgages are not on track to cover the original debt and 39,000 complainants looking to receive approximately £126 million.
+Today in Britain 9.5 million people cannot afford adequate housing conditions, 8 million cannot afford one or more essential good, 7.5 million people do not have enough money to attend social activities and 4 million do not receive proper nutrition.
+
+== Responding to social harms ==
+Whilst the UK and other liberal democracies spend large resources on their respective criminal justice systems, other regulatory and policy responses remain less well funded considering the extent and the serious nature of the harms they seek to prevent. This is illustrated through the following case examples.
+
+=== Regulating the minimum wage ===
+The minimum wage was introduced in 1998 to combat the problem of in-work poverty and inequality. The act established for the first time in the UK a minimum hourly rate of pay. In order, to guarantee that workers received the wage an enforcement structure was created using two methods. These were worker-led Industrial Tribunal claims and the minimum wage enforcement teams (Inland Revenue). Few workers have used the employment tribunals to recover money because many victims of breach of minimum wage are vulnerable, for example, ethnic minorities, youth, uneducated and non-unionised workers. A more likely channel of action is the minimum wage enforcement teams, which are run by the Inland Revenue. These teams have a number of powers including power of entry into workplaces and seizure of employers' records. In order to enforce these regulations through a ‘pyramid of sanctions’, which include: enforcement order, penalty enforcement and prosecution under criminal law. The enforcement order requests the employer to repay the worker any underpayment. If the employer refuses to comply with this requirement, penalty enforcement is issued which orders the firm to not only repay the worker (s), but to also pay a substantial fine. However, if the employer still refuses payment, as a consequence they will face prosecution under criminal law. This action can, however be seen as ineffective as only two companies have ever been prosecuted for such offences. The low rates of enforcement action are demonstrated below.
+Number of cases of non–compliance and regulatory systems
+
+% of non compliance cases that resulted in sanctions

data/en.wikipedia.org/wiki/Zemiology-2.md

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+---
+title: "Zemiology"
+chunk: 3/3
+source: "https://en.wikipedia.org/wiki/Zemiology"
+category: "reference"
+tags: "science, encyclopedia"
+date_saved: "2026-05-05T03:59:10.811479+00:00"
+instance: "kb-cron"
+---
+
+It is estimated by the Low Pay Commission that 146,000–219,000 workers are not receiving the wage they are legally entitled too. It has been suggested that the reasons for relate to the limited resources available to the Inland Revenue Enforcement Teams. The Inland Revenue Enforcement Team consists of 16 compliance teams, each with 3 to 8 officers, based in fourteen towns and cities throughout the UK. In 1999 there were 115 Inspectors which meant that a workplace could expect to be inspected once every 30 years.
+
+=== Policy responses to inequality ===
+Inequality has grown in countries like the UK since the beginning of the 1980s. It is argued that this growth in inequality has had a series of deleterious and harmful effects. These include children's life chances, mental health, physical health, crime and social well-being. Using the example of physical, numerous studies have demonstrated that those from lower socio economic classes have lower life expectancy. For instance a recent research study that investigated differences in health in the 678 electoral wards of the northern region of England found that death rates were four times as high in the poorest 10 per cent of wards as they were in the richest 10 per cent. In the 1980s more and more households fell into poverty and by the early 1990s one in three children lived below the poverty line.
+Inequality is a harm that is perceived as an inherent and largely unpreventable feature of our society. Yet a number of academics attribute the current levels of inequality in the UK to a series of policy decisions that have been made over the last 30 years. The reasons for the growing levels of inequality are numerous. The poorest groups in society have seen their income and wealth affected by developments such as the decreasing value of benefits in real terms, the deregulation of labour markets etc., whilst the rich have seen their wealth grow primarily as a result of the changes made in the UK tax system since 1979. In particular, the top rate of income tax was cut by the Thatcher government in the first post-1979 election budget from 83% to 60%. Then it was cut to 40%. Moreover, tax havens have increased and become common place which has enabled wealthy individuals and companies to avoid taxation regimes. In fact, tax consultants Grant Thornton estimated that the UK's 54 billionaires paid income tax of only £14.7 million in 2006. At least 32 paid no income tax at all. In contrast, according to the Institute for Fiscal Studies, £3.4 billion a year would lift enough families out of poverty to hit Labour's pledge of halving child poverty by 2010.
+
+=== Regulating environmental harm ===
+It is estimated that 24,000 lives are prematurely ended due to the effects of air pollution. Moreover, these health consequences are estimated to cost the UK £29,000 per life year lost in "good" health, £15,000 per life year lost in "poor" health and £1,900–£2,000 per hospital admission. Given the harm caused by air pollution the UK has a poor record in responding to air pollution. The European Union is currently considering prosecuting the British government for breaching air pollution laws. Air pollution near in a number of locations has been recorded at twice the UN's World Health Organization maximum recommended level, which has consequently infringed EU air quality laws. Moreover, the Environment Agency, the UK's principal environmental regulator, has what some may consider to be a poor record of prosecuting infringements of environmental standards. For example, there were 29,627 "substantiated" pollution incidents in 2003, of which 1,337 were considered serious by the agency. However, in the same year the agency prosecuted 266 companies, 61 resulted in fines over £10,000. The average fine for companies was £8,412, down from £8,622 in 2002. There are approximately 20,000 incidents each year in the UK and around 250 prosecutions, which means there is a one in eighty chance of company being prosecuted for these incidents.
+
+=== Regulating health and safety at work ===
+Large numbers of people each year lose their lives due to injuries and diseases that result from their work. In 2007–08, 229 workers were killed at work, whilst 136,771 other injuries to employees were reported under RIDDOR and 299,000 reportable injuries occurred, according to the Labour Force Survey. In addition, 2.1 million people were suffering from an illness they believed was caused or made worse by their current or past work. It is believed that 2056 people died of asbestos related diseases contracted through their work activities. Despite these large scale harms, the principal regulatory in the UK, the Health and Safety Executive, has faced continuing cuts, most notably the 2006 £5.6M reduction in the HSE budget. This has had major implications for the ability of the HSE to regulate workplaces with a decreasing numbers of regulatory contacts. A recent TUC report argued that: Around 85 per cent of major injuries reported to HSE are never investigated ... there is only so much that the 500 or so inspectors in HSE's Field Operations Division (FOD) can achieve. This means that very serious career-ending accidents go unpunished simply because there is no one to gather the evidence. The number of prosecutions is now half what it was in the early 1990s – this simply means that more employers are getting away with it, not that they are more compliant.
+
+== See also ==
+Structural violence
+
+== References ==