Although a Dutch spectacle maker created the compound lens and inserted it in a microscope around the turn of the seventeenth century, and Galileo had applied the principle of the compound lens to the making of his microscope patented in 1609, its possibilities as a microscope had remained unexploited for half a century, until Robert Hooke improved the instrument.

At this time, his proof that white light was a combination of primary colours ( found via prismatics ) replaced the prevailing theory of colours and received an overwhelmingly favourable response, and occasioned bitter disputes with Robert Hooke and others, which forced him to sharpen his ideas to the point where he already composed sections of his later book Opticks by the 1670s in response.

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 Hooke Folio ( see External links below ), describing a demonstration of a balance-controlled watch before the Royal Society, has been held to favour Hooke's claim.

Halley's visits to Newton in 1684 thus resulted from Halley's debates about planetary motion with Wren and Hooke, and they seem to have provided Newton with the incentive and spur to develop and write what became Philosophiae Naturalis Principia Mathematica ( Mathematical Principles of Natural Philosophy ).

An artists impression of English polymath Robert Hooke ( 1635-1703 ) Hooke published his ideas about gravitation in the 1660s and again in 1674 ( see Robert Hooke-Gravitation ).

Hooke told Newton that Hooke had been appointed to manage the Royal Society's correspondence, and wished to hear from members about their researches, or their views about the researches of others ; and as if to whet Newton's interest, he asked what Newton thought about various matters, giving a whole list, mentioning " compounding the celestial motions of the planets of a direct motion by the tangent and an attractive motion towards the central body ", and " my hypothesis of the lawes or causes of springinesse ", and then a new hypothesis from Paris about planetary motions ( which Hooke described at length ), and then efforts to carry out or improve national surveys, the difference of latitude between London and Cambridge, and other items.

Much has been written about the unpleasant side of Hooke's personality, starting with comments by his first biographer, Richard Waller, that Hooke was " in person, but despicable " and " melancholy, mistrustful, and jealous.

Hooke published his ideas about the " System of the World " again in somewhat developed form in 1674, as an addition to " An Attempt to Prove the Motion of the Earth from Observations ".

Hooke therefore wanted to hear from members about their researches, or their views about the researches of others ; and as if to whet Newton's interest, he asked what Newton thought about various matters, giving a whole list, mentioning " compounding the celestial motions of the planetts of a direct motion by the tangent and an attractive motion towards the central body ", and " my hypothesis of the lawes or causes of springinesse ", and then a new hypothesis from Paris about planetary motions ( which Hooke described at length ), and then efforts to carry out or improve national surveys, the difference of latitude between London and Cambridge, and other items.

Arnold, Huygens and Barrow, Newton and Hooke: Pioneers in mathematical analysis and catastrophe theory from evolvents to quasicrystals, Eric J. F.

Along with the inventor and microscopist Robert Hooke ( 1635 – 1703 ), Sir Christopher Wren ( 1632 – 1723 ) and Sir Isaac Newton ( 1642 – 1727 ), English scientist and astronomer Edmond Halley ( 1656 – 1742 ) was trying to develop a mechanical explanation for planetary motion.

Optics, for instance, was revolutionized by people like Robert Hooke, Christiaan Huygens, René Descartes and, once again, Isaac Newton, who developed mathematical theories of light as either waves ( Huygens ) or particles ( Newton ).

Arnold, Huygens and Barrow, Newton and Hooke: Pioneers in mathematical analysis and catastrophe theory from evolvents to quasicrystals, Eric J. F.

By 1679, Hooke thought gravitation had inverse square dependence and communicated this in a letter to Isaac Newton.

Hooke suggested to Isaac Newton in 1679 that the components of orbital motion consisted of inertial motion along a tangent direction plus an attractive motion in the radial direction.

Wren was unconvinced, Hooke did not produce the claimed derivation although the others gave him time to do it, and Halley, who could derive the inverse-square law for the restricted circular case ( by substituting Kepler's relation into Huygens ' formula for the centrifugal force ) but failed to derive the relation generally, resolved to ask Newton.

When Halley asked Newton's opinion on the problem of planetary motions discussed earlier that year between Halley, Hooke and Wren, Newton surprised Halley by saying that he had already made the derivations some time ago ; but that he could not find the papers.

After his 1679-1680 correspondence with Hooke, described below, Newton adopted the language of inward or centripetal force.

In November 1679, Hooke began an exchange of letters with Newton ( of which the full text is now published .).

A short further correspondence developed, and towards the end of it Hooke, writing on 6 January 1679 | 80 to Newton, communicated his " supposition ... that 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.

In 1686, when the first book of Newton's ' Principia ' was presented to the Royal Society, Hooke claimed that Newton had obtained from him the " notion " of " the rule of the decrease of Gravity, being reciprocally as the squares of the distances from the Center ".

Huygens developed a balance spring watch more or less contemporaneously with, though separately from, Robert Hooke, and controversy over who should be given credit for this important invention persisted for centuries.

Henry Sully, writing in Paris in 1717, described the anchor escapement as " an admirable invention of which Dr. Hooke, formerly professor of geometry in Gresham College at London, was the inventor.

Within a year of this date the inventor circulated details of his invention to others, including Robert Hooke in London and Vincenzo Viviani in Florence.

There is evidence to suggest that both Huygens and Hooke later laid claim to the invention, although only within their own countries.

Halley only communicated to Newton the fact " that Hooke had some pretensions to the invention of the rule for the decrease of gravity being reciprocally as the squares of the distances from the centre ," acknowledging at the same time that, though Newton had the notion from him, " yet the demonstration of the curves generated thereby belonged wholly to Newton.

The anchor escapement was probably invented by British scientist Robert Hooke around 1657, although some references credit clockmaker William Clement who popularized the anchor in his invention of the longcase or grandfather clock around 1680, and disputed credit for the escapement with Hooke.

Within a year of this date the inventor circulated details of his invention to others, including Robert Hooke in London and Vincenzo Viviani in Florence.

There is evidence to suggest that both Huygens and Hooke later laid claim to the invention of the spirit level, although only within their own countries.

Hooke clearly postulated mutual attractions between the Sun and planets, in a way that increased with nearness to the attracting body, along with a principle of linear inertia.

While many of his contemporaries believed in the aether as a medium for transmitting attraction or repulsion between separated celestial bodies, Hooke argued for an attracting principle of gravitation in Micrographia of 1665.

In 1676 British physicist Robert Hooke discovered the principle behind springs ' action, that the force it exerts is proportional to its extension, now called Hooke's law.

Newton also firmly claimed that even if it had happened that he had first heard of the inverse square proportion from Hooke, which it had not, he would still have some rights to it in view of his mathematical developments and demonstrations, which enabled observations to be relied on as evidence of its accuracy, while Hooke, without mathematical demonstrations and evidence in favour of the supposition, could only guess ( according to Newton ) that it was approximately valid " at great distances from the center ".

Newton also firmly claimed that even if it had happened that he had first heard of the inverse square proportion from Hooke, which it had not, he would still have some rights to it in view of his mathematical developments and demonstrations, which enabled observations to be relied on as evidence of its accuracy, while Hooke, without mathematical demonstrations and evidence in favour of the supposition, could only guess ( according to Newton ) that it was approximately valid " at great distances from the center ".

Partington even goes so far as to claim that if " Hooke had continued his experiments on combustion it is probable that he would have discovered oxygen ".

Robert Hooke, who often saw Wren two or three times every week, had, as he recorded in his diary, never even heard of her, and was not to meet her till six weeks after the marriage.

Indeed, he knew that before Newton had announced the inverse law, Hooke and Wren and himself had spoken of it and discussed it, and therefore justice demanded that Hooke especially should receive credit for having maintained it as a truth of which he was seeking the demonstration, even though none of them had given a demonstration of the law.

Wren and Halley were both sceptical of Hooke's claims, recalling an occasion when Hooke had claimed to have a derivation of planetary motions under an inverse square law, but had failed to produce it even under the incentive of a prize.

On his father's death in 1648, Robert was left a sum of forty pounds that enabled him to buy an apprenticeship ; with his poor health throughout his life but evident mechanical facility his father had it in mind that he might become a watchmaker or limner, though Hooke was also interested in painting.

Hooke was irascible, at least in later life, proud, and prone to take umbrage with intellectual competitors, though he was by all accounts also a staunch friend and ally and was loyal always to the circle of ardent Royalists with whom he had his early training at Wadham College, particularly Christopher Wren.

Much simpler though, the Goggomobil had bare drive shafts that also acted as the suspension links, with suspension forces passing through the inboard Hooke joints.

As is usual with charters of this period, the authenticity of some of these documents is open to question ( though Della Hooke has established high reliability for the Cornish material ), but that of others ( e. g. Edgar's grant of estates at Tywarnhaile and Bosowsa to his thane Eanulf in 960, Edward the Confessor's grant of estates at Traboe, Trevallack, Grugwith and Trethewey to Bishop Ealdred in 1059 ) is not in any doubt.