Robert Hooke FRS ( / h ʊ k / ; 18 July 1635 – 3 March 1703) was an English scientist who worked as a physicist, astronomer, geologist, meteorologist, and architect. He was one of the first scientists to study living things using a microscope he designed in 1665. Hooke was poor during his early years but later became one of the most important scientists of his time. After the Great Fire of London in 1666, Hooke helped rebuild the city as a surveyor and architect, gaining wealth and respect by completing more than half of the property surveys. Although he was criticized by writers in later years, his reputation was restored by the end of the twentieth century. He is sometimes called "England's Leonardo [da Vinci]."

Hooke was a member of the Royal Society and its first Curator of Experiments starting in 1662. From 1665 to 1703, he also taught geometry at Gresham College. He began his career as an assistant to Robert Boyle, a scientist who studied gases. Hooke built the vacuum pumps used in Boyle’s experiments and conducted his own research. In 1664, Hooke discovered the rotations of Mars and Jupiter. His 1665 book Micrographia introduced the term "cell" and inspired further studies of tiny structures. Hooke studied light refraction and suggested that light behaves like a wave. He also proposed early ideas about how heat causes matter to expand, how air is made of moving particles that create pressure, and how heat is a form of energy.

In physics, Hooke suggested that gravity follows an inverse square law, meaning gravity weakens as the distance between objects increases. He may have been the first to link this idea to planetary motion, a concept later developed by Isaac Newton. This idea caused some disagreement between Hooke and Newton. In geology and paleontology, Hooke studied fossils in rocks and suggested they came from living organisms, challenging the idea that Earth was created exactly as it is today. He identified some fossils as belonging to extinct species, an idea that later supported theories about biological evolution. Hooke also argued that mountains and hills were formed by geological processes over time, not created in their current form.

Life and works

Most information about Robert Hooke's early life comes from an autobiography he started writing in 1696 but never finished. Richard Waller FRS mentioned this in the introduction to a book called The Posthumous Works of Robert Hooke, M.D. S.R.S., published in 1705. Waller's work, along with Lives of the Gresham Professors by John Ward and Brief Lives by John Aubrey, are the main sources of biographical information about Hooke from people who lived close to his time.

Hooke was born in 1635 in Freshwater, Isle of Wight, to Cecily Gyles and John Hooke, an Anglican priest who served as the curate of All Saints' Church in Freshwater. Robert was the youngest of four children (two boys and two girls) by seven years. He was weak and not expected to survive. His father taught him some English, Latin grammar, and religious studies, but Robert's education was not well supported. Left to his own devices, he built small mechanical toys. When he saw a brass clock being taken apart, he made a wooden copy that could work.

Hooke's father died in October 1648, leaving Robert £40 in his will (plus another £10 from his grandmother). At age 13, he took the money to London to become an apprentice to the famous painter Peter Lely. He also received some drawing lessons from Samuel Cowper, a limner, but the smell of paint made his headaches worse. He then became a student at Westminster School, living with its master, Richard Busby. At school, Hooke quickly learned Latin, Greek, and Euclid's Elements. He also learned to play the organ and began studying mechanics. He remained skilled at drawing, as seen in his illustrations for Robert Boyle's work and his own Micrographia.

In 1653, Hooke joined Christ Church, Oxford, where he received free tuition and housing as an organist and chorister, along with a small income as a servitor (though he did not officially join the school until 1658). In 1662, he earned a Master of Arts degree.

While at Oxford, Hooke worked as an assistant to Dr. Thomas Willis, a physician and chemist who was part of the Oxford Philosophical Club. This club was founded by John Wilkins, Warden of Wadham College, and included scientists who later helped form the Royal Society. In 1659, Hooke shared ideas about heavier-than-air flight with the club but concluded human muscles were not strong enough for such a task. Through the club, Hooke met Seth Ward, the Savilian Professor of Astronomy, and helped improve pendulum clocks used for astronomy. Hooke described his time at Oxford as the start of his lifelong love for science. Friends he made there, like Christopher Wren, were important to him throughout his career. Willis introduced Hooke to Robert Boyle, whom the club wanted to bring to Oxford.

In 1655, Boyle moved to Oxford, and Hooke became his assistant, though he worked closely with Boyle on experiments. Boyle was studying gas pressure, and the idea that a vacuum might exist (despite Aristotle's belief that "nature abhors a vacuum") was being explored. Hooke designed an air pump for Boyle's experiments instead of using Ralph Greatorex's pump, which he thought was too crude. Hooke's work helped develop Boyle's law, which later became famous. Hooke also taught Boyle Latin and philosophy, and together they discovered that fire was a chemical reaction, not a basic element of nature as Aristotle had claimed.

According to Henry Robinson, librarian of the Royal Society in 1935: The Royal Society for the Improvement of Natural Knowledge by Experiment was founded in 1660 and received its royal charter in 1662. In 1661, Robert Moray proposed that the society appoint a curator to provide experiments, and Hooke was chosen by Boyle. The society could not fully fund the curator's position, but in 1664, John Cutler gave the society £50 annually to support a "Mechanick" lectureship at Gresham College, with the condition that Hooke be appointed. In 1664, Hooke was confirmed in this role, and in 1665, he became the society's Curator of Experiments for life, earning £80 a year (part from the society and part from Cutler).

In 1663, Hooke was elected a Fellow of the Royal Society (FRS). In 1665, he became the Gresham Professor of Geometry. In 1667, he became acting secretary of the society, and in 1677, he was named joint secretary.

John Aubrey described Hooke as a person of "great virtue and goodness," but many writers have noted his difficult personality. Richard Waller, Hooke's first biographer, said Hooke was "despicable in appearance," and "melancholy, mistrustful, and jealous." These descriptions influenced many writers for over 200 years, leading to portrayals of Hooke as a bitter, selfish, and anti-social person. For example, Arthur Berry claimed Hooke took credit for others' discoveries, and Sullivan called him "unscrupulous" and "vain" in his dealings with Newton. Manuel described Hooke as "cantankerous, envious, and vengeful," while More called him "cynical" and "caustic." Andrade was more sympathetic but still called Hooke "difficult," "suspicious," and "irritable." In 1675, the Royal Society considered expelling Hooke after he criticized Christiaan Huygens over a scientific dispute, but the motion failed.

In 1935, the publication of Hooke's diary revealed new details about his personal life. His biographer, Margaret Espinasse, said the common image of Hooke as a lonely, unhappy person was incorrect. Hooke interacted with skilled artisans like clockmaker Thomas Tompion and instrument-maker Christopher Cocks. He had a lasting friendship with Christopher Wren and often met with John Aubrey. His diary mentions frequent visits to coffeehouses, taverns,

Science

Robert Hooke’s role at the Royal Society was to show experiments he created or those suggested by other members. His early experiments included studying air and observing glass bubbles that collapsed when hot air was trapped inside. He also showed that a dog could survive with its chest open if air was pumped into and out of its lungs. He noticed that venous blood and arterial blood were different and proved that the "food of life" and flames were the same. He also tested gravity, how objects fall, how heavy things are measured, how air pressure changes with height, and how pendulums swing, even those as long as 200 feet (61 meters). His biographer, Margaret Espinasse, called him England’s first meteorologist because he wrote about how to record weather using a thermometer, hygrometer, wind gauge, and a record sheet.

In May 1664, Hooke used a 12-foot (3.7-meter) telescope to observe Jupiter’s Great Red Spot for two hours as it moved across the planet. In March 1665, he shared his findings, and Italian astronomer Giovanni Cassini used them to calculate Jupiter’s rotation time as nine hours and fifty-five minutes.

One of Hooke’s most difficult problems was measuring the distance from Earth to a star other than the Sun. He chose Gamma Draconis and tried using parallax, a method to measure distance. In 1669, he thought he had succeeded, but his tools were not precise enough to get an accurate result.

Hooke’s Micrographia included drawings of the Pleiades star cluster and the Moon’s craters. He studied how craters formed and concluded that the Moon must have gravity, a new idea that challenged old beliefs. He also observed Saturn’s rings and discovered Gamma Arietis, one of the first double stars seen with a telescope.

To make his discoveries, Hooke needed better tools. He invented the Hooke joint, a device that let his instruments follow moving objects smoothly; a clockwork drive to automate movements; and a micrometer screw that allowed precise measurements. He also built the first practical Gregorian telescope using a silvered mirror instead of glass.

In 1660, Hooke discovered the law of elasticity, which explains how springs stretch and contract. He shared his discovery in an anagram, "ceiiinosssttuv," and later wrote "Ut tensio, sic vis," meaning "As the extension, so the force." His work led to the balance spring, a part that helped watches keep accurate time. Though Hooke and Christiaan Huygens had a long debate over who invented it first, Huygens is credited with building the first watch with a balance spring.

Hooke used anagrams to claim credit for discoveries without revealing details. He also used models to study gravity, like how a pendulum moves or how a chain forms a dome shape.

Despite claims that Hooke influenced Thomas Newcomen’s steam engine, this idea is incorrect and was proven wrong.

While others, like Isaac Newton, believed in aether as a force between celestial bodies, Hooke argued that gravity was an attracting force in his 1665 work Micrographia. In 1666, he wrote to the Royal Society that gravity might pull all objects together. His 1674 lecture suggested that gravity affects all celestial bodies but did not yet prove it followed an inverse square law. He admitted he had not tested his ideas fully.

In 1679, Hooke wrote to Newton to discuss scientific ideas, including gravity and planetary motion. Hooke suggested that gravity might decrease with distance, but he did not prove it. In 1686, when Newton’s Principia was shared with the Royal Society, Hooke claimed he had given Newton the idea that gravity weakens with the square of the distance from a center. However, Newton’s work provided the full mathematical proof.

Architecture

Robert Hooke worked as a Surveyor for the City of London and as the chief assistant to Christopher Wren. In these roles, he helped Wren rebuild parts of London after the Great Fire of 1666. Hooke designed several important buildings, including the Monument to the Great Fire of London (1672), Montagu House in Bloomsbury (1674), and Bethlem Royal Hospital (1674), which was later called "Bedlam." Other buildings he designed include the Royal College of Physicians (1679), Aske's Hospital (1679), Ragley Hall in Warwickshire (1680), the Church of St Mary Magdalene at Willen in Buckinghamshire (1680), and Ramsbury Manor in Wiltshire (1681). Hooke also worked on many of the churches in London that were rebuilt after the fire. He was often hired by Wren to help with these projects. From 1671 to 1696, Wren’s office paid Hooke £2,820 for his work, which was more than he earned from his roles at the Royal Society and Cutler Lectureship.

Both Wren and Hooke were interested in astronomy. The Monument to the Great Fire of London was designed to be used as a scientific tool, a type of telescope for observing the stars. However, vibrations from traffic made it difficult to use for this purpose. The design of the monument includes a spiral staircase with no central column and an observation chamber below ground level. Hooke also worked with Wren on the design of St. Paul’s Cathedral. He discovered that the best shape for an arch is an inverted catenary, which led to the idea that a series of circular arches would form the ideal shape for the cathedral’s dome.

After the Great Fire, Hooke suggested redesigning London’s streets into a grid pattern with wide roads. Wren and others also proposed similar ideas. The king decided how much rebuilding would cost and how much compensation would be given. Because it was important to quickly restore trade and population, the city was rebuilt using the original property lines. Hooke was responsible for surveying the ruins to find old foundations, street edges, and property boundaries. He helped create an Act of Common Council in April 1667, which outlined how the original foundations would be officially recognized and documented. According to Lisa Jardine, "in the four weeks from October 4th, Hooke mapped the fire-damaged area, created a system to record land information for London, and prepared building rules for an Act of Parliament to guide the rebuilding." Stephen Inwood noted that Hooke’s survey reports showed a strong ability to understand complicated disputes between neighbors and provide clear, fair solutions.

Hooke also measured and certified land that the government needed to buy for road widening so that people could be paid fairly. In 1670, he was appointed Surveyor of the Royal Works. His detailed surveys helped create Ogilby and Morgan’s large-scale map of London in 1677, which was the first known map of a specific scale (1:1200).

Likenesses

No verified portrait of Robert Hooke has been found. Some people believe this is because of conflicts between Hooke and Isaac Newton, but Hooke’s biographer, Allan Chapman, says this idea is not true. In 1710, a German scholar named Zacharias Conrad von Uffenbach visited the Royal Society and saw portraits of "Boyle and Hoock." These were described as accurate, but only Boyle’s portrait remains today. Hooke’s portrait is missing. During Hooke’s lifetime, the Royal Society met at Gresham College. After Hooke died, Newton became the society’s president, and plans were made to move to new premises. When the society moved in 1710, Hooke’s portrait was the only one that disappeared and has never been found. Hooke’s diary mentions he sat for a portrait by artist Mary Beale, so it is possible such a portrait once existed. However, a book published after Hooke’s death, Posthumous Works of Robert Hooke, by Richard Waller, does not include a portrait of him.

Two written descriptions of Hooke’s appearance from his time survive. His friend John Aubrey described him in middle age. Richard Waller, in The Posthumous Works of Robert Hooke (1705), described Hooke as an older man.

In 1939, Time magazine published a portrait claimed to be of Hooke. However, Ashley Montagu later found no proof that the portrait was linked to Hooke. Montagu noted that the two written descriptions of Hooke match each other but do not match the Time portrait.

In 2003, historian Lisa Jardine suggested a newly discovered portrait might be of Hooke. However, William B. Jensen of the University of Cincinnati later identified the subject as Jan Baptist van Helmont, a Flemish scholar.

Other possible images of Hooke include:
– A seal Hooke used, which shows a profile portrait of a man, possibly Hooke.
– An engraving in the 1728 edition of Chambers’ Cyclopedia depicting a bust of Hooke. It is unclear if this drawing is based on a real portrait.
– A memorial window at St. Helen’s Church, Bishopsgate, London, which was destroyed in the 1993 Bishopsgate bombing. The window was not a realistic likeness.

In 2003, artist Rita Greer created portraits of Hooke based on Aubrey’s and Waller’s descriptions. These images, available under the Free Art License, have been used in books, TV shows, and public relations materials.

In 2019, Larry Griffing, a biology professor at Texas A&M University, suggested a portrait by Mary Beale titled Portrait of a Mathematician might be of Hooke. He noted the person’s features match Hooke’s and that the painting includes details related to Hooke’s work, such as a drawing of elliptical motion and an orrery. Griffing also claimed the background shows Lowther Castle and its church, which Hooke designed. He argued the painting was once owned by the Royal Society but was lost when the society moved in 1710. However, Christopher Whittaker of the University of Durham questioned Griffing’s conclusion, suggesting the portrait might instead show Isaac Barrow. Griffing later defended his claim.

Commemorations

• Asteroid 3514 Hooke, also known as (1971 UJ), is named after Robert Hooke.
• A crater on the Moon and another on Mars are named after him.
• The Hooke Medal is an annual award given by the British Society for Cell Biology to recognize someone who is becoming an important leader in cell biology.
• Between 2005 and 2009, new memorials to Robert Hooke were built to celebrate the 300th anniversary of his death.
• The Boyle-Hooke plaque is located in Oxford.

Works

• Reply of Mr. Hook to the ideas of Mr. Auzout included in a letter written to the author of Philosophical Transactions and some letters exchanged on the topic of large lenses (in French). Paris: Jean Cusson (2nd edition). 1665.
• Lectures on the Restoring Power, or, Of Spring Explaining the Power of Springing Bodies. London: Printed for John Martyn. 1678.
• Micrographia: Hooke, Robert (1635–1703). Micrographia: or Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses with Observations and Inquiries Thereupon.
• Collection of Lectures: Physical, Mechanical, Geographical, and Astronomical. London: Printed for John Martyn, printer to the Royal Society, at the Bell in St. Paul’s Church-yard. 1679. Includes An Attempt to Prove the Annual Motion of the Earth, Animadversions on the Machina Coelestis of Mr. Hevelius, A Description of Helioscopes with Other Instruments, Mechanical Improvement of Lamps, Remarks About Comets 1677, Microscopium, Lectures on the Spring, etc.
• Philosophical Experiments and Observations. London: William Innys & John Innys. 1726.
• The Posthumous Works of Robert Hooke, M.D. S.R.S. Geom. Prof. Gresh. etc. Containing His Cutlerian Lectures and Other Discourses Read at the Meetings of the Illustrious Royal Society… Illustrated with Sculptures. To These Discourses Is Prefixt the Author’s Life, Giving an Account of His Studies and Employments, with an Enumeration of the Many Experiments, Instruments, Contrivances, and Inventions, by Him Made and Produced as Curator of Experiments to the Royal Society. Richard Waller, R.S. Secr. 1705.