A parabolic arch is an arch in the shape of a parabola . In structures, their curve represents an efficient method of load, and so can be found in bridges and in architecture in a variety of forms.
81-399: While a parabolic arch may resemble a catenary arch , a parabola is a quadratic function while a catenary is the hyperbolic cosine , cosh( x ) , a sum of two exponential functions . One parabola is f ( x ) = x + 3 x − 1 , and hyperbolic cosine is cosh( x ) = e + e / 2 . The curves are unrelated. Unlike a catenary arch, the parabolic arch employs
162-518: A through arch ) first appeared in the 1870s, and have been used occasionally ever since; examples include: Catenary arch A catenary arch is a type of architectural arch that follows an inverted catenary curve . The catenary curve has been employed in buildings since ancient times. It forms an underlying principle to the overall system of vaults and buttresses in stone vaulted Gothic cathedrals and in Renaissance domes . It
243-555: A balance-controlled watch before the Royal Society, may support Hooke's claim to priority for the idea. Nevertheless, it is Huygens who is credited with building the first watch to use a balance spring. Hooke's announcement of his law of elasticity using an anagram was a method scientists, such as Hooke, Huygens and Galileo , sometimes used to establish priority for a discovery without revealing details. Hooke used mechanical analogues to understand fundamental processes such as
324-444: A catenary arch cross-section. This shape offers an optimal balance between height and diameter, avoiding the risk of collapsing under the weight of compacted snow. The inside of Budapest ’s Keleti Railway Station forms a catenary arch. The Nubian ton is a burial vault, of Nubia , For greatest stability, the structure’s cross-section follows a catenary arch. The beehive homes (clocháns) of Ireland’s Skellig Michael have
405-570: A catenary shape as well. The Gateway Arch in the American city of St. Louis ( Missouri ) is a catenary arch. Due to aspect ratio , the top being thinner than the bottom, its actual shape is technically a " weighted catenary ". The unfinished Saqqara ostracon has a catenary shape. Marquette Plaza in Minneapolis used catenary arches. Kilns are often designed with catenary arch cross-section . Igloos are designed with
486-408: A catenary, but if they were in the form of a suspension bridges they usually describe a parabola in shape, with the roadway hanging from the inverted arch. Modern suspension bridges were built from the early 19th century, beginning with chains and progressing to more and more elegant steel rope examples, and are still in use today. Parabolic arches that support the roadway from below (or in the form of
567-681: A cross-section that follows the style of a catenary arch. The Rice House has catenary arches. The Icehotel in Sweden employs catenary arches. A catenary bridge has the form of a catenary arch. One famous example is the An-Lan Bridge , in China . In Iraq , the Taq Kasra has the shape of a catenary arch. The roof of Washington Dulles International Airport is a suspended catenary curve. A catenary steel cable system supports
648-499: A curator to furnish the society with experiments, and this was unanimously passed and Hooke was named on Boyle's recommendation. The Society did not have a reliable income to fully fund the post of Curator of Experiments but in 1664, John Cutler settled an annual gratuity of £50 on the Society to found a "Mechanick" lectureship at Gresham College on the understanding the Society would appoint Hooke to this task. On 27 June 1664, Hooke
729-421: A disgruntled, selfish, anti-social curmudgeon. For example, Arthur Berry said Hooke "claimed credit for most of the scientific discoveries of the time". Sullivan wrote he was "positively unscrupulous" and had an "uneasy apprehensive vanity" in dealings with Newton. Manuel described Hooke as "cantankerous, envious, vengeful". According to More, Hooke had both a "cynical temperament" and a "caustic tongue". Andrade
810-490: A dog could be kept alive with its thorax opened, provided air was pumped in and out of its lungs. He noted the difference between venous and arterial blood, and thus demonstrated that the Pabulum vitae ("food of life") and flammae [flames] were the same thing. There were also experiments on gravity, the falling of objects, the weighing of bodies, the measurement of barometric pressure at different heights, and
891-618: A medium for transmitting attraction and repulsion between separated celestial bodies, Hooke argued for an attracting principle of gravitation in Micrographia (1665). In a communication to the Royal Society in 1666, he wrote: I will explain a system of the world very different from any yet received. It is founded on the following positions. 1. That all the heavenly bodies have not only a gravitation of their parts to their own proper centre, but that they also mutually attract each other within their spheres of action. 2. That all bodies having
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#1732800743836972-517: A new hypothesis from Paris about planetary motions, which he described at length; efforts to carry out or improve national surveys; and the difference of latitude between London and Cambridge. Newton's reply offered "a fansy of my own" about a terrestrial experiment rather than a proposal about celestial motions that might detect the Earth's motion; the experiment would use a body suspended in air and then dropped. Hooke wanted to discern how Newton thought
1053-435: A simple motion, will continue to move in a straight line, unless continually deflected from it by some extraneous force, causing them to describe a circle, an ellipse, or some other curve. 3. That this attraction is so much the greater as the bodies are nearer. As to the proportion in which those forces diminish by an increase of distance, I own I have not discovered it. ... Hooke's 1674 Gresham lecture, An Attempt to Prove
1134-624: A spinal deformity that was consistent with a diagnosis of Scheuermann's kyphosis , giving him in middle and later years a "thin and crooked body, over-large head and protruding eyes". Approaching these in a scientific spirit, he experimented with self-medication, diligently recording symptoms, substances and effects in his diary. He regularly used sal ammoniac , emetics, laxatives and opiates, which appear to have had an increasing effect on his physical and mental health over time. Hooke died in London on 3 March 1703, having been blind and bedridden during
1215-418: A vacuum might exist despite Aristotle 's maxim " Nature abhors a vacuum " had just begun to be considered . Hooke developed an air pump for Boyle's experiments rather than use Ralph Greatorex 's pump, which Hooke considered as "too gross to perform any great matter". Hooke's engine enabled the development of the eponymous law that was subsequently attributed to Boyle; Hooke had a particularly keen eye and
1296-407: A very scientific work. I have not yet had time to engage in it; but I find that the conclusions of his demonstrations are, that every part of the catenary is in perfect equilibrium". Architecturally, a catenary arch has the ability to withstand the weight of the material from which it is constructed, without collapsing. For an arch of uniform density and thickness, supporting only its own weight,
1377-470: Is not a parabolic arch . The 17th-century scientist Robert Hooke wrote: " Ut pendet continuum flexile, sic stabit contiguum rigidum inversum ", or, "As hangs a flexible cable so, inverted, stand the touching pieces of an arch." A note written by Thomas Jefferson in 1788 reads, "I have lately received from Italy a treatise on the equilibrium of arches, by the Abbé Mascheroni. It appears to be
1458-558: Is the arch of Taq Kasra . The catenary, spun 180 degrees, forms the structure of simple domed building such as the beehive homes of the Dingle Peninsula , Ireland. The principle of the catenary is also the underlying factor in the much more complex architectural systems of the Medieval and Renaissance architecture. Buildings that have heavy roofs that are arched in shape and deliver a strong outward thrust must comply with
1539-565: Is usually painted of Hooke as a morose ... recluse is completely false". He interacted with noted artisans such as clock-maker Thomas Tompion and instrument-maker Christopher Cocks (Cox). Hooke often met Christopher Wren, with whom he shared many interests, and had a lasting friendship with John Aubrey. His diaries also make frequent reference to meetings at coffeehouses and taverns, as well as to dinners with Robert Boyle. On many occasions, Hooke took tea with his lab assistant Harry Hunt. Although he largely lived alone – apart from
1620-461: The Great Fire of London in 1666, Hooke (as a surveyor and architect) attained wealth and esteem by performing more than half of the property line surveys and assisting with the city's rapid reconstruction. Often vilified by writers in the centuries after his death, his reputation was restored at the end of the twentieth century and he has been called "England's Leonardo [da Vinci] ". Hooke
1701-587: The Great Red Spot of Jupiter for two hours as it moved across the planet's face. In March 1665, he published his findings and from them, the Italian astronomer Giovanni Cassini calculated the rotation period of Jupiter to be nine hours and fifty-five minutes. One of the most-challenging problems Hooke investigated was the measurement of the distance from Earth to a star other than the Sun. Hooke selected
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#17328007438361782-413: The balance spring or hairspring, which for the first time enabled a portable timepiece – a watch – to keep time with reasonable accuracy. A bitter dispute between Hooke and Christiaan Huygens on the priority of this invention was to continue for centuries after the death of both but a note dated 23 June 1670 in the journals of the Royal Society, describing a demonstration of
1863-406: The organ and began his lifelong study of mechanics. He remained an accomplished draughtsman, as he was later to demonstrate in his drawings that illustrate the work of Robert Boyle and Hooke's own Micrographia . In 1653, Hooke secured a place at Christ Church , Oxford , receiving free tuition and accommodation as an organist and a chorister , and a basic income as a servitor , despite
1944-613: The "notion" of "the rule of the decrease of Gravity, being reciprocally as the squares of the distances from the Center". At the same time, according to Edmond Halley 's contemporaneous report, Hooke agreed "the Demonstration of the Curves generated thereby" was wholly Newton's. According to a 2002 assessment of the early history of the inverse square law: "by the late 1660s, the assumption of an 'inverse proportion between gravity and
2025-558: The 1920s, and they appeared occasionally in German expressionist architecture of the 1920s-30s. From the 1940s they gained a new popularity in reinforced concrete, including in shell concrete forms often as hyperbolic parabloids , especially by Felix Candela in Mexico and Oscar Niemeyer in Brazil, but they could be found around the world, especially for churches, in the 1950s and 60s. Since
2106-501: The 1990s Spanish designer Santiago Calatrava has frequently used parabolas for his signature roof structures and bridges. Structures that are self-supporting arches like the Sheffield Winter Garden are often closer to true catenaries. Bridges have used a variety of arches since ancient times, sometimes in very flat segmental arched forms but rarely in the form of a parabola. A simple hanging rope bridge describes
2187-670: The Attraction always is in a duplicate proportion to the Distance from the Center Reciprocall, and Consequently that the Velocity will be in a subduplicate proportion to the Attraction and Consequently as Kepler Supposes Reciprocall to the Distance". (Hooke's inference about the velocity is incorrect. ) In 1686, when the first book of Newton's Principia was presented to the Royal Society, Hooke said he had given Newton
2268-477: The Dutch scientist Antonie van Leeuwenhoek went on to develop increased magnification and so reveal protozoa , blood cells and spermatozoa . Micrographia also contains Hooke's, or perhaps Boyle's and Hooke's, ideas on combustion. Hooke's experiments led him to conclude combustion involves a component of air, a statement with which modern scientists would agree but that was not understood widely, if at all, in
2349-702: The Motion of the Earth by Observations (published 1679), said gravitation applies to "all celestial bodies" and restated these three propositions. Hooke's statements up to 1674 make no mention, however, that an inverse square law applies or might apply to these attractions. His model of gravitation was also not yet universal, though it approached universality more closely than previous hypotheses. Hooke did not provide accompanying evidence or mathematical demonstration; he stated in 1674: "Now what these several degrees [of gravitational attraction] are I have not yet experimentally verified", indicating he did not yet know what law
2430-427: The Royal Society's correspondence; Hooke therefore wanted to hear from members about their research or their views about the research of others. Hooke asked Newton's opinions about various matters. Among other items, Hooke mentioned "compounding the celestial motions of the planets of a direct motion by the tangent and an attractive motion towards the central body"; his "hypothesis of the lawes or causes of springinesse";
2511-519: The Society could scarcely have survived, or, at least, would have developed in a quite different way. It is scarcely an exaggeration to say that he was, historically, the creator of the Royal Society. The Royal Society for the Improvement of Natural Knowledge by Experiment was founded in 1660 and given its Royal Charter in July 1662. On 5 November 1661, Robert Moray proposed the appointment of
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2592-551: The age of 13, he took this to London to become an apprentice to the celebrated painter Peter Lely . Hooke also had "some instruction in drawing" from the limner Samuel Cowper but "the smell of the Oil Colours did not agree with his Constitution, increasing his Head-ache to which he was ever too much subject", and he became a pupil at Westminster School , living with its master Richard Busby . Hooke quickly mastered Latin, Greek and Euclid's Elements ; he also learnt to play
2673-458: The catenary is the ideal curve. Catenary arches are strong because they redirect the vertical force of gravity into compression forces pressing along the arch's curve. In a uniformly loaded catenary arch, the line of thrust runs through its center. This principle has been employed architecturally to create arched structures that follow exactly, and in a visibly apparent way, the form of an inverted catenary. A significant early example of this
2754-452: The correct shape is a parabola. When an arch carries only its own weight, the best shape is a catenary . A hen's egg can be fairly well described as two different paraboloids connected by part of an ellipse . Self-supporting catenary arches appeared occasionally in ancient architecture, for examples in the main arch of the partially ruined Sassanian palace Taq Kasra (now in Iraq ),
2835-440: The deaths of both Newton and Hooke, Alexis Clairaut , mathematical astronomer eminent in his own right in the field of gravitational studies, reviewed Hooke's published work on gravitation. According to Stephen Peter Rigaud , Clairaut wrote: "The example of Hooke and that of Kepler [serves] to show what a distance there is between a truth that is glimpsed and a truth that is demonstrated". I. Bernard Cohen said: "Hooke's claim to
2916-510: The diversion he gave me from my other studies to think on these things & for his dogmaticalness in writing as if he had found the motion in the Ellipsis, which inclined me to try it. Whilst Newton was primarily a pioneer in mathematical analysis and its applications, and optical experimentation, Hooke was a creative experimenter of such great range who left some of his ideas, such as those about gravitation, undeveloped. In 1759, decades after
2997-759: The earliest-recorded observation of a microorganism, the microfungus Mucor . Hooke coined the term " cell ", suggesting a resemblance between plant structures and honeycomb cells. The hand-crafted, leather-and-gold-tooled microscope he designed and used to make the observations for Micrographia , which Christopher Cock made for him in London, is on display at the National Museum of Health and Medicine in Maryland . Hooke's work developed from that of Henry Power , who published his microscopy work in Experimental Philosophy (1663); in turn,
3078-432: The extinction of species, and argued hills and mountains had become elevated by geological processes. By identifying fossils of extinct species, Hooke presaged the theory of biological evolution . Much of what is known of Hooke's early life comes from an autobiography he commenced in 1696 but never completed; Richard Waller FRS mentions it in his introduction to The Posthumous Works of Robert Hooke, M.D. S.R.S. , which
3159-521: The fact he did not officially matriculate until 1658. In 1662, Hooke was awarded a Master of Arts degree. While a student at Oxford, Hooke was also employed as an assistant to Dr Thomas Willis – a physician, chemist and member of the Oxford Philosophical Club . The Philosophical Club had been founded by John Wilkins , Warden of Wadham College , who led this important group of scientists who went on to form
3240-482: The falling body could experimentally reveal the Earth's motion by its direction of deviation from the vertical but Hooke went on hypothetically to consider how its motion could continue if the solid Earth had not been in the way, on a spiral path to the centre. Hooke disagreed with Newton's idea of the body's continuing motion. A further short correspondence developed; towards the end of it, writing on 6 January 1680 to Newton, Hooke communicated his "supposition ... that
3321-465: The first practical Gregorian telescope that used a silvered glass mirror. In 1660, Hooke discovered the law of elasticity that bears his name and describes the linear variation of tension with extension in an elastic spring. Hooke first described this discovery in an anagram "ceiiinosssttuv", whose solution he published in 1678 as Ut tensio, sic vis ("As the extension, so the force"). His work on elasticity culminated in his development of
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3402-400: The form of the catenary curve in order not to collapse. This does not imply that the arches themselves are catenary in form, but that the total system of walls or buttresses that support the roof or dome contain a catenary curve, which delivers the downward thrust. In the 15th century Brunelleschi designed the pointed, octagonal, Gothic dome on Florence Cathedral in a manner that utilised
3483-475: The formation of these craters and concluded their existence meant the Moon must have its own gravity, a radical departure from the contemporaneous Aristotelian celestial model . He also was an early observer of the rings of Saturn , and discovered one of the first-observed double-star systems Gamma Arietis in 1664. To achieve these discoveries, Hooke needed better instruments than those that were available at
3564-463: The foundation of his lifelong passion for science. The friends he made there, particularly Christopher Wren , were important to him throughout his career. Willis introduced Hooke to Robert Boyle , who the Club sought to attract to Oxford. In 1655, Boyle moved to Oxford and Hooke became nominally his assistant but in practice his co-experimenter. Boyle had been working on gas pressures; the possibility
3645-446: The gravitation might follow; and about his whole proposal, he said: "This I only hint at present ... having my self many other things in hand which I would first compleat, and therefore cannot so well attend it" (i.e. "prosecuting this Inquiry"). In November 1679, Hooke initiated a notable exchange of letters with Newton that was published in 1960. Hooke's ostensible purpose was to tell Newton he (Hooke) had been appointed to manage
3726-453: The history of life on Earth and, despite the objections of contemporary naturalists like John Ray – who found the concept of extinction theologically unacceptable – that in some cases they might represent species that had become extinct through some geological disaster. In a series of lectures in 1668, Hooke proposed the then-heretical idea the Earth's surface had been formed by volcanoes and earthquakes, and that
3807-428: The invention was, by Hooke's death, in constant use among clock makers. Hooke announced he conceived a way to build a marine chronometer to determine longitude. and with the help of Boyle and others, he attempted to patent it. In the process, Hooke demonstrated a pocket-watch of his own devising that was fitted with a coil spring attached to the arbour of the balance. Hooke's refusal to accept an escape clause in
3888-472: The inverse-square law has masked Newton's far more fundamental debt to him, the analysis of curvilinear orbital motion. In asking for too much credit, Hooke effectively denied to himself the credit due him for a seminal idea". Hooke made important contributions to the science of timekeeping and was intimately involved in the advances of his time; these included refinement of the pendulum as a better regulator for clocks, increased precision of clock mechanisms and
3969-500: The largest single-span vault of unreinforced brickwork in the world, and the beehive huts of southwestern Ireland . In the modern period, parabolic arches were first used extensively from the 1880s by the Catalan architect Antoni Gaudí , deriving them from catenary arched shapes , constructed of brick or stone, and culminating in the catenary based design of the famous Sagrada Familia . Other Catalan architects then used them into
4050-477: The last year of his life. A chest containing £8,000 in money and gold was found in his room at Gresham College . His library contained over 3,000 books in Latin, French, Italian and English. Although he had talked of leaving a generous bequest to the Royal Society, which would have given his name to a library, laboratory and lectures, no will was found and the money passed to a cousin named Elizabeth Stephens. Hooke
4131-533: The latter were responsible for shell fossils being found far above sea level. In 1835, Charles Lyell , the Scottish geologist and associate of Charles Darwin , wrote of Hooke in Principles of Geology : "His treatise ... is the most philosophical production of that age, in regard to the causes of former changes in the organic and inorganic kingdoms of nature". Hooke's scientific model of human memory
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#17328007438364212-497: The love of his life, and he was devastated when she died in 1687. Inwood also mentions "The age difference between him and Grace was commonplace and would not have upset his contemporaries as it does us". The incestous relationship would nevertheless have been frowned upon and tried by an ecclesiastical court had it been discovered, it was not however a capital felony after 1660. Since childhood, Hooke suffered from migraine , tinnitus , dizziness and bouts of insomnia ; he also had
4293-513: The most ingenious book that ever I read in my life". One of the observations in Micrographia is of fossil wood , the microscopic structure of which Hooke compared to that of ordinary wood. This led him to conclude that fossilised objects like petrified wood and fossil shells such as ammonites were the remains of living things that had been soaked in mineral-laden petrifying water. He believed that such fossils provided reliable clues about
4374-556: The motion of a spherical pendulum and of a ball in a hollow cone, to demonstrate central force due to gravity, and a hanging chain net with point loads to provide the optimum shape for a dome with heavy cross on top. Despite continuing reports to the contrary, Hooke did not influence Thomas Newcomen 's invention of the steam engine ; this myth, which originated in an article in the third edition of " Encyclopædia Britannica ", has been found to be mistaken. While many of Hooke's contemporaries, such as Isaac Newton, believed in aether as
4455-440: The movement of pendulums up to 200 ft long (61 m). His biographer Margaret 'Espinasse described him as England's first meteorologist , in her description of his essay Method for making a history of the weather . (Hooke specifies that a thermometer, a hygrometer , a wind gauge and a record sheet be used for proper weather records. ) In May 1664, using a 12 ft (3.7 m) refracting telescope , Hooke observed
4536-561: The nucleus of the Royal Society . In 1659, Hooke described to the Club some elements of a method of heavier-than-air flight but concluded human muscles were insufficient to the task. Through the Club, Hooke met Seth Ward (the University's Savilian Professor of Astronomy ) and developed for Ward a mechanism that improved the regularity of pendulum clocks used for astronomical time-keeping. Hooke characterised his Oxford days as
4617-546: The principle of the catenary arch. In the 17th century, Christopher Wren designed the dome of St Paul's Cathedral based directly on a catenary curve. The vaulted roof and buttresses of Kings College Chapel , Cambridge, have been discovered to comply with the formula of the catenary arch. Rainbow Natural Bridge in the U.S. state of Utah has a natural catenary shape, possibly produced by weathering in high-stress areas. Kolob Arch and Landscape Arch , also in Utah, have
4698-408: The principle that when weight is uniformly applied above, the internal compression (see line of thrust ) resulting from that weight will follow a parabolic curve . Of all arch types, the parabolic arch produces the most thrust at the base. Also, it can span the widest area. It is commonly used in bridge design, where long spans are needed. When an arch carries a uniformly distributed vertical load,
4779-698: The proposed exclusive contract for the use of this idea resulted in its abandonment. Hooke developed the principle of the balance spring independently of Huygens and at least five years beforehand. Huygens published his own work in Journal de Scavans in February 1675 and built the first functioning watch to use a balance spring. In 1663 and 1664, Hooke made his microscopic, and some astronomic, observations, which he collated in Micrographia in 1665. His book, which describes observations with microscopes and telescopes, as well as original work in biology, contains
4860-539: The roof of Denver International Airport . New York City ’s Pennsylvania Station has a roof in the form of a catenary arch. On the Federal Reserve Bank of Minneapolis , the building has been remodeled, but still visible is the catenary arch suspending the original building. Cameroon 's musgum mud huts have a catenary cross-section. Robert Hooke Robert Hooke FRS ( / h ʊ k / ; 18 July 1635 – 3 March 1703)
4941-576: The rotations of Mars and Jupiter . Hooke's 1665 book Micrographia , in which he coined the term cell , encouraged microscopic investigations. Investigating optics – specifically light refraction – Hooke inferred a wave theory of light . His is the first-recorded hypothesis of the cause of the expansion of matter by heat, of air's composition by small particles in constant motion that thus generate its pressure, and of heat as energy. In physics, Hooke inferred that gravity obeys an inverse square law and arguably
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#17328007438365022-498: The servants who ran his home – his niece Grace Hooke and his cousin Tom Giles lived with him for some years as children. Hooke never married. According to his diary, Hooke had a sexual relationship with his niece Grace, after she had turned 16. Grace was in his custody since the age of 10. He also had sexual relations with several maids and housekeepers. Hooke's biographer Stephen Inwood considers Grace to have been
5103-467: The seventeenth century. He also concluded respiration and combustion involve a specific and limited component of air. According to Partington, if "Hooke had continued his experiments on combustion, it is probable that he would have discovered oxygen". Samuel Pepys wrote of the book in his diary on 21 January 16 64 / 65 : "Before I went to bed I sat up till two o’clock in my chamber reading of Mr. Hooke's Microscopicall Observations,
5184-449: The square of distance' was rather common and had been advanced by a number of different people for different reasons". In the 1660s, Newton had shown for planetary motion under a circular assumption, force in the radial direction had an inverse-square relation with distance from the centre. Newton, who in May 1686 was presented with Hooke's claim to priority on the inverse square law, denied he
5265-455: The star Gamma Draconis and chose the method of parallax determination. In 1669, after several months of observing, Hooke believed the desired result had been achieved. It is now known his equipment was far too imprecise to obtain an accurate measurement. Hooke's Micrographia contains illustrations of the Pleiades star cluster and lunar craters . He conducted experiments to investigate
5346-826: The supposition, could only guess it was approximately valid "at great distances from the centre". Newton did accept and acknowledge, in all editions of the Principia , Hooke and others had separately appreciated the inverse square law in the solar system. Newton acknowledged Wren, Hooke and Halley in this connection in his "Scholium to Proposition 4" in Book 1. In a letter to Halley, Newton also acknowledged his correspondence with Hooke in 1679–1680 had reawakened his dormant interest in astronomical matters but that did not mean, according to Newton, Hooke had told Newton anything new or original. Newton wrote: Yet am I not beholden to him for any light into that business ... but only for
5427-459: The time. Accordingly, he invented three new mechanisms: the Hooke joint , a sophisticated universal joint that allowed his instruments to smoothly follow the apparent motion of the observed body; the first clockwork drive to automate the process; and a micrometer screw that allowed him to achieve a precision of ten seconds of arc . Hooke was dissatisfied with refracting telescopes so he built
5508-432: The type in which he was involved seem almost to be the rule rather than the exception. And Hooke's reaction to such controversy involving his own discoveries and inventions seems mild in comparison to the behaviour of some of his contemporaries". The publication of Hooke's diary in 1935 revealed previously unknown details about his social and familial relationships. His biographer Margaret 'Espinasse said: "the picture which
5589-415: The use of the balance spring to improve the timekeeping of watches. Galileo had observed the regularity of a pendulum and Huygens first incorporated it in a clock; in 1668, Hooke demonstrated his new device to keep a pendulum swinging regularly in unsteady conditions. His invention of a tooth-cutting machine enabled a substantial improvement in the accuracy and precision of timepieces. Waller reported
5670-453: Was a Fellow of the Royal Society and from 1662, he was its first Curator of Experiments. From 1665 to 1703, he was also Professor of Geometry at Gresham College . Hooke began his scientific career as an assistant to the physical scientist Robert Boyle . Hooke built the vacuum pumps that were used in Boyle's experiments on gas law and also conducted experiments. In 1664, Hooke identified
5751-435: Was an English polymath who was active as a physicist ("natural philosopher"), astronomer, geologist, meteorologist and architect. He is credited as one of the first scientists to investigate living things at microscopic scale in 1665, using a compound microscope that he designed. Hooke was an impoverished scientific inquirer in young adulthood who went on to become one of the most important scientists of his time. After
5832-404: Was an adept mathematician, neither of which applied to Boyle. Hooke taught Boyle Euclid's Elements and Descartes 's Principles of Philosophy ; it also caused them to recognise fire as a chemical reaction and not, as Aristotle taught, a fundamental element of nature. According to Henry Robinson, Librarian of The Royal Society in 1935: Without his weekly experiments and prolific work
5913-520: Was appointed its Joint Secretary. Although John Aubrey described Hooke as a person of "great virtue and goodness". much has been written about the unpleasant side of Hooke's personality. According to his first biographer Richard Waller, Hooke was "in person, but despicable", and "melancholy, mistrustful, and jealous". Waller's comments influenced other writers for more than 200 years such that many books and articles – especially biographies of Isaac Newton – portray Hooke as
5994-471: Was buried at St Helen's Church, Bishopsgate , in the City of London but the precise location of his grave is unknown. Hooke's role at the Royal Society was to demonstrate experiments from his own methods or at the suggestion of members. Among his earliest demonstrations were discussions of the nature of air and the implosion of glass bubbles that had been sealed with enclosed hot air. He also demonstrated that
6075-436: Was confirmed to the office and on 11 January 1665, he was named Curator by Office for life with an annual salary of £80, which consisting of £30 from the Society and Cutler's £50 annuity. In June 1663, Hooke was elected a Fellow of the Royal Society (FRS). On 20 March 1665, he was also appointed Gresham Professor of Geometry . On 13 September 1667, Hooke became acting Secretary of the Society and on 19 December 1677, he
6156-545: Was frail and not expected to live. Although his father gave him some instruction in English, (Latin) Grammar and Divinity , Robert's education was largely neglected. Left to his own devices, he made little mechanical toys; seeing a brass clock dismantled, he built a wooden replica that "would go". Hooke's father died in October 1648, leaving £40 in his will to Robert (plus another £10 held over from his grandmother). At
6237-485: Was more sympathetic but still described Hooke as "difficult", "suspicious" and "irritable". In October 1675, the Council of the Royal Society considered a motion to expel Hooke because of an attack he made on Christiaan Huygens over scientific priority in watch design but it did not pass. According to Hooke's biographer Ellen Drake: if one studies the intellectual milieu of the time, the controversies and rivalries of
6318-646: Was one of the first of its kind. In a 1682 lecture to the Royal Society, Hooke proposed a mechanical analogue model of human memory that bore little resemblance to the mainly philosophical models of earlier writers. This model addressed the components of encoding, memory capacity, repetition, retrieval, and forgetting – some with surprisingly modern accuracy. According to psychology professor Douglas Hintzman, Hooke's model's most-interesting points are that it allows for attention and other top-down influences on encoding; it uses resonance to implement parallel, cue-dependent retrieval; it explains memory for recency; it offers
6399-645: Was printed in 1705. The work of Waller, along with John Ward 's Lives of the Gresham Professors , and John Aubrey 's Brief Lives form the major near-contemporaneous biographical accounts of his life. Hooke was born in 1635 in Freshwater, Isle of Wight , to Cecily Gyles and the Anglican priest John Hooke, who was the curate of All Saints' Church, Freshwater . Robert was the youngest, by seven years, of four siblings (two boys and two girls); he
6480-515: Was the first to hypothesise such a relation in planetary motion, a principle Isaac Newton furthered and formalised in Newton's law of universal gravitation . Priority over this insight contributed to the rivalry between Hooke and Newton. In geology and palaeontology , Hooke originated the theory of a terraqueous globe, thus disputing the Biblical view of the Earth's age; he also hypothesised
6561-509: Was to be credited as author of the idea, giving reasons including the citation of prior work by others. Newton also said that, even if he had first heard of the inverse square proportion from Hooke (which Newton said he had not), he would still have some rights to it because of his mathematical developments and demonstrations. These, he said, enabled observations to be relied upon as evidence of its accuracy while according to Newton, Hooke, without mathematical demonstrations and evidence in favour of
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