142-450: Micrographia: or Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses. With Observations and Inquiries Thereupon is a historically significant book by Robert Hooke about his observations through various lenses. It was the first book to include illustrations of insects and plants as seen through microscopes. Published in January 1665, the first major publication of
284-455: A kite came to his cradle and opened his mouth with its tail; commentators still debate whether the anecdote was an actual memory or a fantasy. In the mid-1460s, Leonardo's family moved to Florence, which at the time was the centre of Christian Humanist thought and culture. Around the age of 14, he became a garzone (studio boy) in the workshop of Andrea del Verrocchio , who was the leading Florentine painter and sculptor of his time. This
426-576: 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 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
568-555: 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
710-602: 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 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
852-461: A commission from the Monks of San Donato a Scopeto. It is a complex composition, of about 250 x 250 centimetres. Leonardo did numerous drawings and preparatory studies, including a detailed one in linear perspective of the ruined classical architecture that forms part of the background. In 1482 Leonardo went to Milan at the behest of Lorenzo de' Medici in order to win favour with Ludovico il Moro, and
994-499: 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
1136-421: 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
1278-490: 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
1420-612: A finger in her bible to mark the place and raises her hand in a formal gesture of greeting or surprise. This calm young woman appears to accept her role as the Mother of God , not with resignation but with confidence. In this painting, the young Leonardo presents the humanist face of the Virgin Mary, recognising humanity's role in God's incarnation. In the 1480s, Leonardo received two very important commissions and commenced another work that
1562-469: A frequent namesake and subject in culture . Leonardo is identified as one of the greatest painters in the history of Western art and is often credited as the founder of the High Renaissance. Despite having many lost works and fewer than 25 attributed major works – including numerous unfinished works – he created some of the most influential paintings in
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#17327721942601704-537: A fur-lined cloak. On 12 August 1519, Leonardo's remains were interred in the Collegiate Church of Saint Florentin at the Château d'Amboise. Some 20 years after Leonardo's death, Francis was reported by the goldsmith and sculptor Benvenuto Cellini as saying: "There had never been another man born in the world who knew as much as Leonardo, not so much about painting, sculpture and architecture, as that he
1846-454: A hundred years it was described by one viewer as "completely ruined." Leonardo, instead of using the reliable technique of fresco, had used tempera over a ground that was mainly gesso , resulting in a surface subject to mould and to flaking. Despite this, the painting remains one of the most reproduced works of art; countless copies have been made in various mediums. Toward the end of this period, in 1498 Leonardo's trompe-l'œil decoration of
1988-665: A letter which described the diverse things that he could achieve in the fields of engineering and weapon design, and mentioned that he could paint. He brought with him a silver string instrument – either a lute or lyre – in the form of a horse's head. With Alberti, Leonardo visited the home of the Medici and through them came to know the older Humanist philosophers of whom Marsiglio Ficino , proponent of Neoplatonism ; Cristoforo Landino , writer of commentaries on Classical writings, and John Argyropoulos , teacher of Greek and translator of Aristotle were
2130-646: A local oral tradition recorded by the historian Emanuele Repetti , is that he was born in Anchiano , a country hamlet that would have offered sufficient privacy for the illegitimate birth, though it is still possible he was born in a house in Florence that Ser Piero almost certainly had. Leonardo's parents both married separately the year after his birth. Caterina – who later appears in Leonardo's notes as only "Caterina" or "Catelina" –
2272-584: A mechanism that improved the regularity of pendulum clocks used for astronomical time-keeping. Hooke characterised his Oxford days as 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;
2414-618: 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
2556-517: 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
2698-594: A painting commission of unknown subject matter, but cancelled it when the artist set about developing a new kind of varnish . Leonardo became ill, in what may have been the first of multiple strokes leading to his death. He practised botany in the Vatican Gardens , and was commissioned to make plans for the Pope's proposed draining of the Pontine Marshes . He also dissected cadavers , making notes for
2840-432: A particularly keen eye and 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
2982-419: 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 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
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#17327721942603124-456: A posthumous inventory of his belongings; it was assessed at 505 lire, an exceptionally high valuation for a small panel portrait. Despite the thousands of pages Leonardo left in notebooks and manuscripts, he scarcely made reference to his personal life. Within Leonardo's lifetime, his extraordinary powers of invention, his "great physical beauty" and "infinite grace," as described by Vasari , as well as all other aspects of his life, attracted
3266-734: A priest to make his confession and to receive the Holy Sacrament . Vasari also records that the King held Leonardo's head in his arms as he died, although this story may be legend rather than fact. In accordance with his will, sixty beggars carrying tapers followed Leonardo's casket. Melzi was the principal heir and executor, receiving, as well as money, Leonardo's paintings, tools, library and personal effects. Leonardo's other long-time pupil and companion, Salaì, and his servant Baptista de Vilanis, each received half of Leonardo's vineyards . His brothers received land, and his serving woman received
3408-409: A professor of art history and visual culture, studied Hooke's artistic influences and processes with the help of some newly rediscovered notes and drawings that appear to show some of his work leading up to Micrographia. She observes, "Hooke's use of the term "schema" to identify his plates indicates that he approached his images in a diagrammatic manner and implies the study or visual dissection of
3550-410: A rich flowing garment, raised wings and bearing a lily. Although previously attributed to Ghirlandaio, the larger work is now generally attributed to Leonardo. In the smaller painting, Mary averts her eyes and folds her hands in a gesture that symbolised submission to God's will. Mary is not submissive, however, in the larger piece. The girl, interrupted in her reading by this unexpected messenger, puts
3692-643: A rocky landscape rather than architectural details. The painting was eventually finished; in fact, two versions of the painting were finished: one remained at the chapel of the Confraternity, while Leonardo took the other to France. The Brothers did not get their painting, however, nor the de Predis their payment, until the next century. Leonardo's most remarkable portrait of this period is the Lady with an Ermine , presumed to be Cecilia Gallerani ( c. 1483–1490 ), lover of Ludovico Sforza. The painting
3834-435: 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
3976-632: A single-system account of repetition and priming; and the power law of forgetting can be derived from the model's assumption in a straightforward way. On 8 July 1680, Hooke observed the nodal patterns associated with the modes of vibration of glass plates. He ran a bow along the edge of a flour-covered glass plate and saw the nodal patterns emerge. In acoustics, in 1681, Hooke showed the Royal Society that musical tones can be generated using spinning brass cogs cut with teeth in particular proportions. Leonardo da Vinci Leonardo di ser Piero da Vinci (15 April 1452 – 2 May 1519)
4118-624: 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
4260-492: A successful career. Despite his family history, Leonardo only received a basic and informal education in (vernacular) writing, reading, and mathematics; possibly because his artistic talents were recognised early, so his family decided to focus their attention there. Later in life, Leonardo recorded his earliest memory, now in the Codex Atlanticus . While writing on the flight of birds, he recalled as an infant when
4402-450: A time. This was beyond the comprehension of the prior of the convent, who hounded him until Leonardo asked Ludovico to intervene. Vasari describes how Leonardo, troubled over his ability to adequately depict the faces of Christ and the traitor Judas , told the duke that he might be obliged to use the prior as his model. The painting was acclaimed as a masterpiece of design and characterisation, but it deteriorated rapidly, so that within
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4544-406: A town plan of Imola in order to win his patronage. Upon seeing it, Cesare hired Leonardo as his chief military engineer and architect. Later in the year, Leonardo produced another map for his patron, one of Chiana Valley , Tuscany, so as to give his patron a better overlay of the land and greater strategic position. He created this map in conjunction with his other project of constructing a dam from
4686-513: A treatise on vocal cords ; these he gave to an official in hopes of regaining the Pope's favour, but he was unsuccessful. In October 1515, King Francis I of France recaptured Milan. On 21 March 1516 Antonio Maria Pallavicini, the French ambassador to the Holy See , received a letter sent from Lyon a week previously by the royal advisor Guillaume Gouffier, seigneur de Bonnivet , containing
4828-401: A very young man: a local peasant made himself a round buckler shield and requested that Ser Piero have it painted for him. Leonardo, inspired by the story of Medusa , responded with a painting of a monster spitting fire that was so terrifying that his father bought a different shield to give to the peasant and sold Leonardo's to a Florentine art dealer for 100 ducats , who in turn sold it to
4970-460: Is characterised by the pose of the figure with the head turned at a very different angle to the torso, unusual at a date when many portraits were still rigidly in profile. The ermine plainly carries symbolic meaning, relating either to the sitter, or to Ludovico who belonged to the prestigious Order of the Ermine . Leonardo's most famous painting of the 1490s is The Last Supper , commissioned for
5112-502: 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 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
5254-541: Is speculation that since one of the accused, Lionardo de Tornabuoni, was related to Lorenzo de' Medici, the family exerted its influence to secure the dismissal. Since that date much has been written about his presumed homosexuality and its role in his art, particularly in the androgyny and eroticism manifested in Saint John the Baptist and Bacchus and more explicitly in a number of erotic drawings. Despite
5396-482: Is the only extant example of Leonardo's sculpture. Leonardo was otherwise free to pursue his scientific interests. Many of Leonardo's most prominent pupils either knew or worked with him in Milan, including Bernardino Luini , Giovanni Antonio Boltraffio , and Marco d'Oggiono . In 1507, Leonardo was in Florence sorting out a dispute with his brothers over the estate of his father, who had died in 1504. By 1508, Leonardo
5538-573: Is usually identified as the Caterina Buti del Vacca, who married the local artisan Antonio di Piero Buti del Vacca, nicknamed L'Accattabriga , 'the quarrelsome one'. Ser Piero married Albiera Amadori – having been betrothed to her the previous year – and after her death in 1464, went on to have three subsequent marriages. From all the marriages, Leonardo eventually had 16 half-siblings (of whom 11 survived infancy) who were much younger than he (the last
5680-565: 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
5822-614: Is widely regarded to have been a genius who epitomised the Renaissance humanist ideal, and his collective works comprise a contribution to later generations of artists matched only by that of his younger contemporary Michelangelo . Born out of wedlock to a successful notary and a lower-class woman in, or near, Vinci , he was educated in Florence by the Italian painter and sculptor Andrea del Verrocchio . He began his career in
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5964-584: The Duke of Milan . By 1472, at the age of 20, Leonardo qualified as a master in the Guild of Saint Luke , the guild of artists and doctors of medicine, but even after his father set him up in his own workshop, his attachment to Verrocchio was such that he continued to collaborate and live with him. Leonardo's earliest known dated work is a 1473 pen-and-ink drawing of the Arno valley (see below). According to Vasari,
6106-532: 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
6248-680: The Mona Lisa , the Last Supper , and the Virgin of the Rocks . Leonardo first gained attention for his work on the Baptism of Christ , painted in conjunction with Verrocchio. Two other paintings appear to date from his time at Verrocchio's workshop, both of which are Annunciations . One is small, 59 centimetres (23 in) long and 14 cm (5.5 in) high. It is a " predella " to go at
6390-687: 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 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
6532-529: The Renaissance . Some of his smaller inventions, however, entered the world of manufacturing unheralded, such as an automated bobbin winder and a machine for testing the tensile strength of wire. He made substantial discoveries in anatomy , civil engineering, hydrodynamics , geology, optics , and tribology , but he did not publish his findings and they had little to no direct influence on subsequent science. Leonardo da Vinci, properly named Leonardo di ser Piero da Vinci ("Leonardo, son of ser Piero from Vinci"),
6674-402: The Royal Society , it became the first scientific best-seller, inspiring a wide public interest in the new science of microscopy . The book originated the biological term cell . Hooke most famously describes a fly 's eye and a plant cell (where he coined that term because plant cells, which are walled, reminded him of the cells in a honeycomb ). Known for its spectacular copperplate of
6816-831: The Sala delle Asse was painted for the Duke of Milan in the Castello Sforzesco . In 1505, Leonardo was commissioned to paint The Battle of Anghiari in the Salone dei Cinquecento (Hall of the Five Hundred) in the Palazzo Vecchio , Florence. Leonardo devised a dynamic composition depicting four men riding raging war horses engaged in a battle for possession of a standard, at the Battle of Anghiari in 1440. Michelangelo
6958-458: The Western canon . The Mona Lisa is his best known work and is the world's most famous individual painting. The Last Supper is the most reproduced religious painting of all time and his Vitruvian Man drawing is also regarded as a cultural icon. In 2017, Salvator Mundi , attributed in whole or part to Leonardo, was sold at auction for US$ 450.3 million , setting a new record for
7100-413: 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
7242-477: The most expensive painting ever sold at public auction. Revered for his technological ingenuity , he conceptualised flying machines, a type of armoured fighting vehicle , concentrated solar power, a ratio machine that could be used in an adding machine , and the double hull . Relatively few of his designs were constructed or were even feasible during his lifetime, as the modern scientific approaches to metallurgy and engineering were only in their infancy during
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#17327721942607384-494: 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 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
7526-417: The wave theory of light , the organic origin of fossils , and other philosophical and scientific interests of its author. Hooke also selected several objects of human origin; among these objects were the jagged edge of a honed razor and the point of a needle, seeming blunt under the microscope. His goal may well have been to contrast the flawed products of mankind with the perfection of nature (and hence, in
7668-613: 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
7810-507: The 1490s Leonardo had already been described as a "Divine" painter. Among the qualities that make Leonardo's work unique are his innovative techniques for laying on the paint; his detailed knowledge of anatomy, light, botany and geology; his interest in physiognomy and the way humans register emotion in expression and gesture; his innovative use of the human form in figurative composition; and his use of subtle gradation of tone. All these qualities come together in his most famous painted works,
7952-474: The 16th century that these relationships were of a sexual or erotic nature. Walter Isaacson in his biography of Leonardo makes explicit his opinion that the relations with Salaì were intimate and homosexual. Earlier in Leonardo's life, court records of 1476, when he was aged twenty-four, show that Leonardo and three other young men were charged with sodomy in an incident involving a known male prostitute. The charges were dismissed for lack of evidence, and there
8094-670: 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
8236-402: The Baptist , a work that won such admiration that "men [and] women, young and old" flocked to see it "as if they were going to a solemn festival." In Cesena in 1502, Leonardo entered the service of Cesare Borgia , the son of Pope Alexander VI , acting as a military architect and engineer and travelling throughout Italy with his patron. Leonardo created a map of Cesare Borgia's stronghold,
8378-498: The Confraternity of the Immaculate Conception and The Last Supper for the monastery of Santa Maria delle Grazie . In the spring of 1485, Leonardo travelled to Hungary (on behalf of Sforza) to meet king Matthias Corvinus , and was commissioned by him to paint a Madonna . In 1490 he was called as a consultant, together with Francesco di Giorgio Martini , for the building site of the cathedral of Pavia and
8520-526: The Duke of Milan to paint the Sala delle Asse in the Sforza Castle , c. 1498. The project became a trompe-l'œil decoration that made the great hall appear to be a pergola created by the interwoven limbs of sixteen mulberry trees, whose canopy included an intricate labyrinth of leaves and knots on the ceiling. When Ludovico Sforza was overthrown by France in 1500, Leonardo fled Milan for Venice , accompanied by his assistant Salaì and friend,
8662-477: 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
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#17327721942608804-405: The French king's instructions to assist Leonardo in his relocation to France and to inform the artist that the King was eagerly awaiting his arrival. Pallavicini was also asked to reassure Leonardo that he would be well received at court, both by the King and by his mother, Louise of Savoy . Leonardo entered Francis's service later that year, and was given the use of the manor house Clos Lucé near
8946-462: The Holy Family on the road to Egypt. The painting demonstrates an eerie beauty as the graceful figures kneel in adoration around the infant Christ in a wild landscape of tumbling rock and whirling water. While the painting is quite large, about 200×120 centimetres , it is not nearly as complex as the painting ordered by the monks of San Donato, having only four figures rather than about fifty and
9088-472: The King's residence at the royal Château d'Amboise . He was frequently visited by Francis, and drew plans for an immense castle town the King intended to erect at Romorantin . He also made a mechanical lion, which during a pageant walked towards the King and – upon being struck by a wand – opened its chest to reveal a cluster of lilies. Leonardo was accompanied during this time by his friend and apprentice Francesco Melzi, and
9230-702: 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
9372-427: 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";
9514-519: 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
9656-414: The art of combining complex figure compositions with detailed architectural backgrounds. Piero della Francesca had made a detailed study of perspective , and was the first painter to make a scientific study of light. These studies and Leon Battista Alberti 's treatise De pictura were to have a profound effect on younger artists and in particular on Leonardo's own observations and artworks. Much of
9798-643: The artistic skills of drawing, painting, sculpting, and modelling. Leonardo was a contemporary of Botticelli, Ghirlandaio and Perugino, who were all slightly older than he was. He would have met them at the workshop of Verrocchio or at the Platonic Academy of the Medici . Florence was ornamented by the works of artists such as Donatello's contemporaries Masaccio , whose figurative frescoes were imbued with realism and emotion, and Ghiberti , whose Gates of Paradise , gleaming with gold leaf , displayed
9940-475: The base of a larger composition, a painting by Lorenzo di Credi from which it has become separated. The other is a much larger work, 217 cm (85 in) long. In both Annunciations, Leonardo used a formal arrangement, like two well-known pictures by Fra Angelico of the same subject, of the Virgin Mary sitting or kneeling to the right of the picture, approached from the left by an angel in profile, with
10082-613: The city, but then spent much time in the service of Ludovico Sforza in Milan. Later, he worked in Florence and Milan again, as well as briefly in Rome , all while attracting a large following of imitators and students. Upon the invitation of Francis I , he spent his last three years in France, where he died in 1519. Since his death, there has not been a time where his achievements, diverse interests, personal life , and empirical thinking have failed to incite interest and admiration, making him
10224-523: The curiosity of others. One such aspect was his love for animals, likely including vegetarianism and according to Vasari, a habit of purchasing caged birds and releasing them. Leonardo had many friends who are now notable either in their fields or for their historical significance, including mathematician Luca Pacioli , with whom he collaborated on the book Divina proportione in the 1490s. Leonardo appears to have had no close relationships with women except for his friendship with Cecilia Gallerani and
10366-440: 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
10508-510: 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
10650-759: 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,
10792-482: 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
10934-465: 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
11076-465: 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 the Great Fire of London in 1666, Hooke (as a surveyor and architect) attained wealth and esteem by performing more than half of
11218-509: The foreground sprawls his symbol, a great lion whose body and tail make a double spiral across the base of the picture space. The other remarkable feature is the sketchy landscape of craggy rocks against which the figure is silhouetted. The daring display of figure composition, the landscape elements and personal drama also appear in the great unfinished masterpiece, the Adoration of the Magi ,
11360-528: The foremost. Also associated with the Platonic Academy of the Medici was Leonardo's contemporary, the brilliant young poet and philosopher Pico della Mirandola . In 1482, Leonardo was sent as an ambassador by Lorenzo de' Medici to Ludovico il Moro , who ruled Milan between 1479 and 1499. Leonardo worked in Milan from 1482 until 1499. He was commissioned to paint the Virgin of the Rocks for
11502-475: 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
11644-446: 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
11786-453: 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
11928-530: The household of his paternal grandfather, Antonio da Vinci, but it is possible that he spent the years before then in the care of his mother in Vinci, either Anchiano or Campo Zeppi in the parish of San Pantaleone. He is thought to have been close to his uncle, Francesco da Vinci, but his father was probably in Florence most of the time. Ser Piero, who was the descendant of a long line of notaries, established an official residence in Florence by at least 1469 and had
12070-428: 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
12212-472: 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
12354-477: 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
12496-533: 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
12638-497: 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
12780-499: The mathematician Luca Pacioli . In Venice, Leonardo was employed as a military architect and engineer, devising methods to defend the city from naval attack. On his return to Florence in 1500, he and his household were guests of the Servite monks at the monastery of Santissima Annunziata and were provided with a workshop where, according to Vasari, Leonardo created the cartoon of The Virgin and Child with Saint Anne and Saint John
12922-443: The miniature world, particularly its fold-out plates of insects , the text itself reinforces the tremendous power of the new microscope . The plates of insects fold out to be larger than the large folio itself, the engraving of the louse in particular folding out to four times the size of the book. Although the book is best known for demonstrating the power of the microscope, Micrographia also describes distant planetary bodies ,
13064-513: 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
13206-556: 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
13348-440: 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
13490-405: The next thirty years. Salaì executed a number of paintings under the name of Andrea Salaì, but although Vasari claims that Leonardo "taught him many things about painting," his work is generally considered to be of less artistic merit than others among Leonardo's pupils, such as Marco d'Oggiono and Boltraffio . At the time of his death in 1524, Salaì owned a painting referred to as Joconda in
13632-419: The objects he presented within a round frame, thus offering viewers an evocation of the experience of looking through the lens of a microscope." Robert Hooke Robert Hooke FRS ( / h ʊ k / ; 18 July 1635 – 3 March 1703) was an English polymath who was active as a physicist ("natural philosopher"), astronomer, geologist, meteorologist and architect. He is credited as one of
13774-422: The objects portrayed." Identifying Hooke's schema as 'organization tools,' she emphasizes: Hooke built up his images from numerous observations made from multiple vantage points, under varying lighting conditions, and with lenses of differing powers. Similarly his specimens required a great deal of manipulation and preparation in order to make them visible through the microscope. Additionally: "Hooke often enclosed
13916-799: The only two large equestrian statues of the Renaissance, Donatello 's Gattamelata in Padua and Verrocchio's Bartolomeo Colleoni in Venice, and became known as the Gran Cavallo . Leonardo completed a model for the horse and made detailed plans for its casting , but in November 1494, Ludovico gave the metal to his brother-in-law to be used for a cannon to defend the city from Charles VIII of France . Contemporary correspondence records that Leonardo and his assistants were commissioned by
14058-482: The painting in Verrocchio's workshop was done by his assistants. According to Vasari, Leonardo collaborated with Verrocchio on his The Baptism of Christ ( c. 1472–1475 ), painting the young angel holding Jesus's robe with skill so far superior to his master's that Verrocchio purportedly put down his brush and never painted again (the latter claim probably being apocryphal). The new technique of oil paint
14200-448: The painting is barely begun, the composition can be seen and is very unusual. Jerome , as a penitent , occupies the middle of the picture, set on a slight diagonal and viewed somewhat from above. His kneeling form takes on a trapezoid shape, with one arm stretched to the outer edge of the painting and his gaze looking in the opposite direction. J. Wasserman points out the link between this painting and Leonardo's anatomical studies. Across
14342-430: The painting was abandoned. The third important work of this period is the Virgin of the Rocks , commissioned in Milan for the Confraternity of the Immaculate Conception. The painting, to be done with the assistance of the de Predis brothers , was to fill a large complex altarpiece . Leonardo chose to paint an apocryphal moment of the infancy of Christ when the infant John the Baptist , in protection of an angel, met
14484-583: The papacy (as Leo X); Leonardo went to Rome that September, where he was received by the pope's brother Giuliano . From September 1513 to 1516, Leonardo spent much of his time living in the Belvedere Courtyard in the Apostolic Palace , where Michelangelo and Raphael were both active. Leonardo was given an allowance of 33 ducats a month and, according to Vasari, decorated a lizard with scales dipped in quicksilver . The pope gave him
14626-492: 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 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
14768-406: The possibility 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
14910-698: 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
15052-447: The recent awareness and admiration of Leonardo as a scientist and inventor, for the better part of four hundred years his fame rested on his achievements as a painter. A handful of works that are either authenticated or attributed to him have been regarded as among the great masterpieces. These paintings are famous for a variety of qualities that have been much imitated by students and discussed at great length by connoisseurs and critics. By
15194-528: The refectory of the Convent of Santa Maria della Grazie in Milan. It represents the last meal shared by Jesus with his disciples before his capture and death, and shows the moment when Jesus has just said "one of you will betray me", and the consternation that this statement caused. The writer Matteo Bandello observed Leonardo at work and wrote that some days he would paint from dawn till dusk without stopping to eat and then not paint for three or four days at
15336-471: 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 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
15478-503: The sea to Florence, in order to allow a supply of water to sustain the canal during all seasons. Leonardo had left Borgia's service and returned to Florence by early 1503, where he rejoined the Guild of Saint Luke on 18 October of that year. By this same month, Leonardo had begun working on a portrait of Lisa del Giocondo , the model for the Mona Lisa , which he would continue working on until his twilight years. In January 1504, he
15620-498: 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
15762-467: 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,
15904-422: The son of a Lombard aristocrat, who is considered to have been his favourite student. The Council of Florence wished Leonardo to return promptly to finish The Battle of Anghiari , but he was given leave at the behest of Louis XII , who considered commissioning the artist to make some portraits. Leonardo may have commenced a project for an equestrian figure of d'Amboise; a wax model survives and, if genuine,
16046-451: The spirit of the times, of biblical creation). Published under the aegis of the Royal Society , the popularity of the book helped further the society's image and mission of being England's leading scientific organization. Micrographia 's illustrations of the miniature world captured the public's imagination in a radically new way; Samuel Pepys called it "the most ingenious book that ever I read in my life". In 2007, Janice Neri ,
16188-449: 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
16330-455: 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
16472-826: 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
16614-459: 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
16756-765: The two Este sisters, Beatrice and Isabella . While on a journey that took him through Mantua , he drew a portrait of Isabella that appears to have been used to create a painted portrait, now lost. Beyond friendship, Leonardo kept his private life secret. His sexuality has been the subject of satire, analysis, and speculation. This trend began in the mid-16th century and was revived in the 19th and 20th centuries, most notably by Sigmund Freud in his Leonardo da Vinci, A Memory of His Childhood . Leonardo's most intimate relationships were perhaps with his pupils Salaì and Melzi . Melzi, writing to inform Leonardo's brothers of his death, described Leonardo's feelings for his pupils as both loving and passionate. It has been claimed since
16898-432: 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
17040-415: 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
17182-513: The young Leonardo was the first to suggest making the Arno river a navigable channel between Florence and Pisa . In January 1478, Leonardo received an independent commission to paint an altarpiece for the Chapel of Saint Bernard in the Palazzo Vecchio , an indication of his independence from Verrocchio's studio. An anonymous early biographer, known as Anonimo Gaddiano , claims that in 1480 Leonardo
17324-540: Was 65, which may indicate why he left works such as the Mona Lisa unfinished. He continued to work at some capacity until eventually becoming ill and bedridden for several months. Leonardo died at Clos Lucé on 2 May 1519 at the age of 67, possibly of a stroke. Francis I had become a close friend. Vasari describes Leonardo as lamenting on his deathbed, full of repentance, that "he had offended against God and men by failing to practice his art as he should have done." Vasari states that in his last days, Leonardo sent for
17466-482: Was a very great philosopher." Salaì , or Il Salaino ("The Little Unclean One", i.e., the devil), entered Leonardo's household in 1490 as an assistant. After only a year, Leonardo made a list of his misdemeanours, calling him "a thief, a liar, stubborn, and a glutton," after he had made off with money and valuables on at least five occasions and spent a fortune on clothes. Nevertheless, Leonardo treated him with great indulgence, and he remained in Leonardo's household for
17608-542: Was about the time of the death of Verrocchio's master, the great sculptor Donatello . Leonardo became an apprentice by the age of 17 and remained in training for seven years. Other famous painters apprenticed in the workshop or associated with it include Ghirlandaio , Perugino , Botticelli , and Lorenzo di Credi . Leonardo was exposed to both theoretical training and a wide range of technical skills, including drafting, chemistry, metallurgy, metal working, plaster casting, leather working, mechanics, and woodwork, as well as
17750-481: Was an Italian polymath of the High Renaissance who was active as a painter, draughtsman, engineer, scientist, theorist, sculptor, and architect. While his fame initially rested on his achievements as a painter, he has also become known for his notebooks , in which he made drawings and notes on a variety of subjects, including anatomy, astronomy, botany, cartography, painting, and palaeontology . Leonardo
17892-559: Was applied to areas of the mostly tempera work, including the landscape, the rocks seen through the brown mountain stream, and much of Jesus's figure, indicating Leonardo's hand. Additionally, Leonardo may have been a model for two works by Verrocchio: the bronze statue of David in the Bargello and the archangel Raphael in Tobias and the Angel . Vasari tells a story of Leonardo as
18034-520: 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
18176-549: Was back in Milan, living in his own house in Porta Orientale in the parish of Santa Babila. In 1512, Leonardo was working on plans for an equestrian monument for Gian Giacomo Trivulzio , but this was prevented by an invasion of a confederation of Swiss, Spanish and Venetian forces, which drove the French from Milan. Leonardo stayed in the city, spending several months in 1513 at the Medici's Vaprio d'Adda villa. In March 1513, Lorenzo de' Medici's son Giovanni assumed
18318-650: 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 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
18460-460: Was born on 15 April 1452 in, or close to, the Tuscan hill town of Vinci , 20 miles from Florence . He was born out of wedlock to Piero da Vinci (Ser Piero da Vinci d'Antonio di ser Piero di ser Guido; 1426–1504), a Florentine legal notary , and Caterina di Meo Lippi ( c. 1434–1494 ), from the lower class. It remains uncertain where Leonardo was born; the traditional account, from
18602-484: Was born when Leonardo was 46 years old) and with whom he had very little contact. Very little is known about Leonardo's childhood and much is shrouded in myth, partially because of his biography in the frequently apocryphal Lives of the Most Excellent Painters, Sculptors, and Architects (1550) by 16th-century art historian Giorgio Vasari . Tax records indicate that by at least 1457 he lived in
18744-471: 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
18886-436: 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
19028-448: 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 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
19170-597: Was living with the Medici and often worked in the garden of the Piazza San Marco, Florence , where a Neoplatonic academy of artists, poets and philosophers organised by the Medici met. In March 1481, he received a commission from the monks of San Donato in Scopeto for The Adoration of the Magi . Neither of these initial commissions were completed, being abandoned when Leonardo went to offer his services to Duke of Milan Ludovico Sforza . Leonardo wrote Sforza
19312-485: 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
19454-491: Was of ground-breaking importance in terms of composition. Two of the three were never finished, and the third took so long that it was subject to lengthy negotiations over completion and payment. One of these paintings was Saint Jerome in the Wilderness , which Bortolon associates with a difficult period of Leonardo's life, as evidenced in his diary: "I thought I was learning to live; I was only learning to die." Although
19596-646: 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
19738-528: Was part of a committee formed to recommend where Michelangelo's statue of David should be placed. He then spent two years in Florence designing and painting a mural of The Battle of Anghiari for the Signoria, with Michelangelo designing its companion piece, The Battle of Cascina . In 1506, Leonardo was summoned to Milan by Charles II d'Amboise , the acting French governor of the city. There, Leonardo took on another pupil, Count Francesco Melzi ,
19880-425: Was struck by the equestrian statue of Regisole , of which he left a sketch. Leonardo was employed on many other projects for Sforza, such as preparation of floats and pageants for special occasions; a drawing of , and wooden model for, a competition to design the cupola for Milan Cathedral ; and a model for a huge equestrian monument to Ludovico's predecessor Francesco Sforza . This would have surpassed in size
20022-522: Was supported by a pension totalling 10,000 scudi . At some point, Melzi drew a portrait of Leonardo ; the only others known from his lifetime were a sketch by an unknown assistant on the back of one of Leonardo's studies ( c. 1517 ) and a drawing by Giovanni Ambrogio Figino depicting an elderly Leonardo with his right arm wrapped in clothing. The latter, in addition to the record of an October 1517 visit by Louis d'Aragon , confirms an account of Leonardo's right hand being paralytic when he
20164-509: 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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