Robert Hooke - The Greatest Experimental Scientist of the Seventeenth Century Science

One science only will one genius fit; So vast is art, so narrow human wit. Alexander Pope while writing about the specialized science Newton was creating.

Together Malpighi, Grew, Swammerdan. Hooke and the estimable Leeuwenhoek brought not only an added dimension to the investigations into the life sciences, but a new and unbiased approach to those investigations. While none could be said to be without a philosophy, for the most part each peered into his microscope to discover and record what he saw there rather than to prove or disprove some ancient or new theory. Ray Spangenburgh and Diane K. Moser in The History of Science: From the Ancient Greeks to the Scientific Revolution. Universities Press (India) Limited, 1999. Hooke had no rival as a deviser of instruments; the microscope, telescope and barometer were all much improved by him and his other inventions included a revolving drum recorder for pressure and temperature, and a universal joint. His contribution to science is unusual; he did much, but his devices and ideas were largely developed by others. The Cambridge Dictionary of Scientists (2nd edition). Cambridge University Press, 2002. One of the most brilliant and versatile scientists of his day, he (Hooke) was also an argumentative individual who became involved in a number of controversies, including several priority disputes with Isaac Newton. He anticipated the development of the steam engine….He also anticipated Newton’s law of the inverse square in gravitation (1678), constructed the first Gregorian or reflecting telescope…” Chamber Biographical Dictionary (Centenary Edition), Chambers Harrap Publishers Ltd. 1997

Robert Hooke was one of the greatest inventors of the seventeenth century. Hooke’s interests knew no bounds. He made important contributions in many areas namely astronomy, optics, mechanics, geography, geology, architecture, materials, clock-making, naval technology, chemistry, microbiology and palaentology. He correctly formulated the theory of elasticity, the kinetic hypothesis of gases and the nature of combustion. His mechanical skill was unparalleled. He was unsurpassed in the seventeenth century as an inventor and designer of scientific instruments. It was Hooke, who first introduced the use of balance spring for the regulation of watches. He also made improvements in pendulum clocks and invented a machine for cutting the teeth of watch wheels. He greatly improved the microscope, telescope and the barometer. He invented a revolving drum recorder for pressure and temperature and a universal joint. His other inventions included an odometer, an ‘otocousticon’ as an aid to hearing, a reflecting quadrant, a land carriage, a diving bell and a method of telegraphy. He ascertained the number of vibrations corresponding to musical notes.. He anticipated the method for showing nodal lines in vibrating surfaces, the motion of the Sun among stars, correct notions as to the nature of fossils and the succession of living things on Earth. He published his extraordinary book Micrographia in 1665, which proved to be major milestone in the history of science. Hooke was the first meteorologist to keep records. He was also first to use freezing water as zero. Hooke was first to suggest that in general all matter expands on heating and that the air is made up of particles separated from each other by relatively large distances. He left many of his devices and ideas to be developed by others. Hooke was one of the founders of the Royal Society of London. Hooke’s contribution in making the Royal Society a professional body from a ‘club of virtuosi’ is quite significant. A vituoso, the plural of which is virtuosi, refers to a learned person with broad interest in arts and science. It was Hooke, who worded the Royal Society’s credo, “To improve the knowledge of natural things, and all useful Arts, Manufactures, Mechanic practices, Engines and Inventions by Experiments (not meddling with divinity, Metaphysics, Morals, Politics, Grammar, Rhetoric or Logic)”. Hooke worked with Robert Boyle (1627-91) as his paid assistant. He also collaborated with scientists as diverse as Christian Huygens (1629-95), Anton van Leeuwenhoek (1632-1723), Chrisotpher Wren (1632-1723) and Isaac Newton (1642-1727). Hooke’s reputation suffered from his many controversies with other scientists over question of priority. The most prominent among those with whom Hooke quarreled was Isaac Newton. There is no doubt that Newton’s genius far outshined Hooke’s. But Hooke’s achievements were also quite impressive. However, unfortunately if today Hooke is known it is because of Hooke’s Law of Elasticity and for his quarrels with Newton and not because of his varied contributions, which greatly helped to shape the seventeenth century science. No portrait of Hooke is in existence. Even the location of his grave is not known today. Hooke was born in the little town of Freshwater in the Isle of Wight on July 18, 1635. His father John Hooke was a clergyman at All Saint’s Curch. The church stands at the end of what is now Hooke Road. In his childhood Hooke suffered a lot, both physically and emotionally. One was not very sure about his survival during his first 7 years. He suffered headaches, insomnia, indigestion and several other ailments. He could hardly eat anything except milk. As a child he was inflicted by smallpox. Though he survived but he was scarred physically and emotionally for life. Since his childhood, Hooke displayed considerable skill in mechanical things. As a child he not only made a model warship (3 feet long) with rigging and guns that could be fired but also sailed it on the broad stretch of water, the river Yar. He made a working clock out of wood and sundial. He had copied the local painter’s work. When Hooke was thirteen, his father hanged himself. Hooke received 100 pound inheritance from his father. After the death of his father, Hooke went to London as an apprentice to the painter Sir Peter Lely. It is with Lely, Hooke developed his artistic skill. However, Hooke did not remain long with Sir Lely as he could not withstand the fumes of the pigments. Hooke entered the Westminister School of Richard Busby. Students dreaded Busby, who had the reputation for “flogging sense into them”. Busby recognized Hooke’s genius and he finally took young Hooke into his own home. Hooke’s intelligence combined with his unusual mechanical skill brought him to the notice of Busby. Hooke was on good terms with Busby throughout his life. It has been reported that Hooke mastered the first six books of Euclid’s Elements in his first week at the Westminister School. He also learnt to play the organ and to speak Latin, Greek and a bit of Hebrew. Hooke left Westminister in 1653 and moved to the Oxford, where he acquired a place as chorister at the Christ Church. As chorister Hooke received a modest endowment. In Oxford, Hooke came in contact with some of the best scientists in England and some of whom would go on to establish the Royal Society of London. They were impressed by Hooke’s skill at designing experiments and building equipment and they encouraged him in many scientific endeavours. At Oxford he studied astronomy with Set Ward and he assisted Thomas Willis (1621-75), the English anatomist, who made important studies of anatomy of the brain. Willis recommended Hooke to Robert Boyle, who appointed him as his paid assistant. Hooke assisted Boyle in constructing the air pump. While working as Boyle’s assistant, Hooke performed experiments in which he immobilized a dog’s lungs but kept the dog alive by blowing air into them. These experiments were the first demonstrations of artificial respiration. By conducting experiments with an air pump, Hooke demonstrated that it was the air in the blood and not the actual movements of the lungs, which kept an animal alive. On November 12, 1662 Hooke was appointed Curator of Experiments at the Royal Society. He was the first person to hold this post. The post, which was initially temporary, was made permanent in 1665 at a salary of 30 pounds per annum with apartments in Gresham College, Bishopsgate St. He lived there for the remainder of his life. As a Curator of Experiments, Hooke was to report or demonstrate three to four major experiments in every weekly meeting of the Royal Society. It was a highly challenging task. Hooke performed this task excellently for thirty-one years. He was also nominated Professor of Geometry, Gresham College. On October 25, 1677, Hooke became Secretary to the Royal Society, a post he held till 1682. Today there is no way of knowing of how Hooke looked like as no portrait of his or likeness exists. He is often described as an ugly–looking person. Here we quote two persons closely associated with Hooke—his co-worker-cum-biographer and a close friend. Richard Walker who published a biography of Hooke in 1705 wrote: “…in person but despicable, being crooked and low of stature, and as he grew older more and more deformed. He was always very pale and lean, and latterly nothing but skin and bone, with a meager aspect, his eyes gray and full, with a sharp ingenious look whilst younger. He wore his own hair of dark brown colour, very long, and hanging neglected over his face uncut and lank, which about three years before his death he cut off and wore a periwig. He went stooping and very fast, having but a light body to carry, and a great deal of spirits and activity, especially in his youth. He was of an active, restless, indefatigable genius, even almost to the last, and always slept little to his death, oftenest continuing his studies all night, and taking a short nap in the day. His temper was melancholy, mistrustful, and jealous, which more increased upon him with years.” His close friend John Aubrey wrote: “…of middling stature, something crooked, pale faced, and his face but little below, but his head is large; his eye full and popping, and not quick; a gray eye. He has a delicate head of haire browne, and of an excellent moist curle.” In 1670 Hooke discovered his law of elasticity. It states that the stretching of a solid body is proportional to the force applied to it. Hooke’s law of elasticity laid the foundation for studies for stress and strain and for understanding of elastic materials. He made use of these studies in his designs for the balance springs of watches. Hooke was a keen observer of fossils. He was the first person to observe fossils under a microscope. He observed close similarities between the structures of petrified wood and fossil shells on the one hand, and living wood and living mollusk shells on the other. The fossils were known and discussed since the time of Aristotle. It was generally believed that fossils were formed and grew within the Earth. The stones (fossils) that looked like living beings were actually not the remains of living beings but were created by a shaping force, or “extraordinary Plastick virtue”. During the Renaissance (the great revival of art, literature, and learning in Europe in the 14th, 15th, and 16th centuries based on classical sources) scholars such as Konrad Gesner collected and displayed fossils in museums and cabinets. However, the scientists had no idea regarding the nature and origin of fossils till the late 17th century. Even in the seventeenth century, a number of hypotheses had been proposed for the origin of fossils. Hooke’s studies on fossil made him realize that fossils are not “sports of nature” but they are remains of once-living organisms. Other naturalists like Bernard Pallisy (1510-90) and Nicolaus Steno (1638-86) that fossils were petrified animal and plant remains that had been infiltrated into solid rocks by floods. The theory proposed by Hooke for explaining the origin and nature of fossils was later proved to be correct. However, when Hooke proposed his theory of fossils, time was not ripe for its acceptance. A section of naturalists were particularly disturbed by the existence of fossils of species no longer seen. They argued that God the Creator being perfect would not allow a species created by Him to perish. This group tried to explain the existence of fossils in many ways. Some of these explanations were: i) Like crystals, fossils are also the direct products of nature. They form in their own right and are not remains of other species. ii) They may be seen as Plato’s ideal forms—free floating and they simply got embedded themselves into rocks. iii) Fossils were seen as tests of God. They were placed in rocks by God to test the faith of humankind with their riddle. Hooke had anticipated, 250 years before Charles Darwin, that the fossil record documents changes among the organisms on the Earth. He had realized that species have both appeared and gone extinct throughout the history of life on the Earth. Hooke’s Micrographia (“Tiny Drawings) was published in 1665. The book covered a variety of fields. It was a book with elaborate drawings of various things viewed by Hooke with a compound microscope and illumination system (a device that concentrated light on the viewing area of his double lensed microscopes), which he himself devised. Hooke observed organisms as diverse as insects, sponges, bryozoans (minute water animals that form branching, mosslike colonies and reproduce by budding), foraminifera (marine protozoans with calcareous shells full of tiny holes through which slender filaments project), and bird feathers. Micrographia was an accurate and detailed record of his observations. Most of the 57 illustrations contained in the book were drawn by Hooke himself and some might have been done by the famed Christopher Wren. The illustrations were so exacting that one could see the eye of a fly, the shape of the stinging organ of a bee, the anatomies of flea and louse, the structure of feathers and the form of molds. In Micrographia, Hooke described his wave theory of light. He compared the spreading of light vibrations to that of waves in water. Micrographia also included a series of observations of lunar craters and Hooke’s speculations as to the origin of these features. Hooke thought moon craters were caused either by collisions or boiling mud. Crystallography had its birth in this book. The book contained illustrations of the crystal structure of snowflakes. He discussed the possibility of manufacturing artificial fibres by a process similar to the spinning of the silkworm. In Micrographia, Hooke coined the word cell to describe the features of plant tissues he was able to discover under the microscope. He called them “cells” because they resembled the mosaic cells that monks lived in at the time. Hooke had no definite idea about the function of the cells found in plant tissues. He thought that like arteries and veins in animal body the cells might serve as channels to carry fluids through the plant material. The Micrographia also contained Hooke’s theory of fossils. The book was a best-seller of its day. It has been reported that one government official named Samuel Pepys stayed up till 2:00 AM one night to read Micrographia, of which he said, “the most ingenious book that I ever read in my life.” As it normally happens all did not like the book. Some even ridiculed. One satirist of those dayd poked fun at Hook as “ a Sot (a fool), that has spent 2000 pounds in Microscopes, to find out the nature of Eels in Vinegar, Mites in Cheese, and the Blue of Plums which he has subtly found out to be living creature.” A condensed version of Micrographia was published in 1745. It was titled Micrographia Restaurata. It had shorter explanation bit it contained all the figures, which were reproduced from Hooke’s original plates. Hooke spent a great deal of time in understanding the mysteries of the universe. It was Hooke, who first reported the Great Red Spot of Jupiter and he also established the rotation of this giant planet. In 1664 Hooke discovered the fifth star in the Trapezium, an asterism in the constellation Orion. Hooke’s detailed drawings of Mars (1666) enabled its period of rotation to be found more than 200 years later. Hooke made the earliest attempt (July-October 1669) at measuring the parallax of a fixed star. Hooke’s results led to Bradley’s discovery of stellar aberration. In 1674 Hooke published ‘An Attempt to Prove the Motion of the Earth by Observations.’ This was the first recorded observation of a star in daylight. Around 1666, Hooke published a book entitled Cometa. It contained Hooke’s close observations of the comets of 1664 and 1665 and also data of other astronomers. It also included a statement of the Law of Inverse Squares and the effect of Sun on comet tails. A great deal of interest was sparked in Newton by this book. He mentioned about this book in his notes and also in his correspondences. Hooke noted one of the earliest examples of a double star. He made pioneering contribution to designing of astronomical instruments. He built the first reflecting telescope. He was first to insist on the importance of resolving power and the advantage of using hair lines in place of silk or metal wire. In 1666 Hooke suggested that the force of gravity could be measured by utilizing the motion of a pendulum and he also attempted to demonstrate that the Earth and the Moon follow an elliptical path around the Sun. In 1672 Hooke discovered the phenomenon of diffraction and he proposed the wave theory of light to esplain this phenomenon. In 1678 Hooke anticipated the inverse square law to describe planetary motions. Hooke was an important architect of his times. After the Great Fire which destroyed the City of London, Hooke had exhibited a model for rebuilding the City. Hooke’s model was not adopted. However, the City authorities appointed Hooke a City Surveyor together with Edward Jerman and Peter Mills and also (appointed by the King) Wren, Hugh May and Roger Pratt. Hooke and Wren jointly were responsible for The Monument to the Great Fire. Hooke was not given due credit for his architectural works. Hooke designed the Bethelhem Hospital, Montague House and the Royal College of Physicians. All these structures were demolished in the 19th century. He also designed the Ragley Hall (Warwickshire) and Willen Church in Buckinghamshire. No account of Hooke’s life can be complete without mentioning his much discussed confrontations with Newton. The first confrontation between Newton and Hooke took place in 1672 when the former was presenting his paper on his demonstration of white light being a composite of other colours. Newton thought very high of his demonstration. He referred to it as “the oddest if not the most considerable detection we hath hitherto been made in the operations of Nature.” But Hooke felt it otherwise. Hooke had his own theory of light and he had written about it in his Micrographia. He claimed that more details were necessary to prove Newton’s claim. Hooke was not alone in challenging Newton’s claim. Christian Huygens, Ignace Pardies and the Jesuits of Liege joined Hooke. Particularly Hooke and Huygens rejected Newton’s claim that his theory was simply derived with certainty from experiments. Newton was furious with Hooke. Since his childhood Newton was extremely vulnerable to criticism. Throughout his life Newton challenged authority. He even decided to give up the Fellowship of the Royal society. However, after a lot of persuation by Henry Oldenburg, the then Secretary of the Royal Society, Newton changed his mind. Oldenburg not only offered an apology for the behaviour of an “unnamed member’ but also agreed to wave Newton’s dues to the Society. Newton scored a victory over Hooke. The next major confrontation between Hooke and Newton that publicly erupted in 1684 had something to do with the publication of Newton’s Principia. Hooke claimed priority in the formulation of the inverse square law of gravitation. Contrary to Hooke’s claim Newton thought that Hooke had nothing to do with it. Many science historians have accepted Newton’s claim. However, Hooke’s claim was not totally unfounded. Hooke had indeed anticipated the law of square inverse. At the suggestion of Hooke, Newton agreed to exchange correspondence to sort out the problem Several letters exchanged between Hooke and Newton on the subject. But when Hooke made their correspondence public Newton refused to correspond any further. Hooke in one of his letters to Newton, talked about the theory of gravity but he had answer from Newton acknowledging Hooke’s theory. On not getting any response from Newton, Hooke appealed to Halley saying that Newton had taken the entire credit for the theory of gravity inspite of the fact that it was Hooke who had given the idea to Newton. Halley was in a fix. It was Halley who had persuaded Newton to publish Principia and he himself was paying for its publication. So Halley was worried that Newton may change his mind and stop its publication. Halley wrote to Newton : “He (Hooke) says you had the notion from him… how much of this is so you know best , as likewise what you have to do in this matter, only Mr. Hooke seems to expect you should make some mention of him in the preface, which, it is possible, you may see reason to prefix.” Newton simply refused to accept any claim of Hooke. Halley wrote a second letter to Newton in which he pointed out that Hooke was not trying to lay claim to the entire theory. He also pointed out that Hooke had not made a formal complaint of the matter. But Newton did not change his mind. He refused to share his credit with anyone and most certainly not with Hooke. He even refused to write the third book of Principia. Halley had no option other than to go along with Newton. He had already invested much of his own resources in the publication of the first two books. The Principia was formally presented to the Royal Society in 1687. Again Newton scored a victory over Hooke. The book had no mention of Hooke. Newton’s aversion to Hooke did not end by not giving credit to Hooke for the theory of gravity. During his Presidentship of the Royal Society Newton had severed all ties that bound the Society to Hooke. Hooke’s portrait, the only one known to exist in the Royal Society, disappeared. Most of Hooke’s instruments, papers and scientific contrivances, which Hooke had fashioned with his own hands also disappeared. This has deprived the posterity to know all the contributions to the advancement of science Hooke really made. Newton’s antipathy towards Hooke was so great that even 20 years after Hooke’s death, Newton could not speak of Hooke without loosing his calmness. Before he died, Hooke wanted to give his life savings (Hooke spent very little of his money and kept it locked in an iron chest) to the Royal Society for constructing new quarters, meeting rooms and a library. Though he did not make any will for this purpose but e had expressed his desire to Richard Walker. Based on Walker’s testimony the Royal Society could have claimed the money but Newton decided to the contrary. Hooke had certainly negative traits in him. But he certainly deserved a better treatment in the hands of Newton. As Kathy A. Miles has written: “Robert Hooke may have had his faults, and he may have been too quick to make assertions, but he most certainly does not deserve his fate or lack of his recognition. Newton’s action in severing all ties between Hooke and the (Royal) Society did nothing to further the knowledge of science and its development and denied the rest of us of the opportunity to know all the contributions to the advancement of science Hooke really made. Newton once said: “if I have seen further, it is by standing on the shoulders of giants”. There can be little doubt that one of these giants was Robert Hooke. It seems that it would apparently be more appropriate to consider Hooke as the sower of many of the seeds in Newton’s garden.” Hooke died on March 3, 1703, at Gresham College having been blind and bedridden the last year of his life. He was buried at St Helen’s Bishopsgate. His remains were exhumed and reburied somewhere in North London sometime in the 19th century ans so his final burial place is unknown. The Hooke Memorial Window was destroyed in the Bishopsgate bombing in the 1980s. There is a small museum devoted to Hooke at his Father’s church in Freshwater. References Seeing Further: The Legacy of Robert Hooke by Kathy A. Miles www.starryskies.com/~kmiles/spec/hooks.htm (this article was published in Griffith Observer, June 1996) Engines of our Ingenuity No.1751:Robert Hooke by John H. Lienhard. www.uh.edu/engines/epi1751.htm. Engines of Our Ingenuity No.350: Boyle’s Lab Assistant by John H. Lienhard. www.uh.edu/engines/epi350.htm. The History of Science: From the Ancient Greeks to the Scientific Revolution by Ray Spagenburg and Diane K. Moser. Hyderabad: Universities Press (India) Limited, 1999. The Cambridge Dictionary of Scientists (Second Edition) byDavid, Ian, John and Margaret Millar. Cambridge: Cambridge University Press, 2002. Robert Hooke by Margaret Espinasse. Berkely: University of California Press, 1962. Age of Kings by Charles Blitzer. New York: Time Incorporated, 1969. Chambers Biographical Dictionary. Centenary Edition. New York: Chambers Harrap Publishers Ltd., 1997. A Dictionary of Scientists. Oxfod: Oxford University Press, 1999.