Robert Hooke FRS The eminent scientist Robert Hooke was an English polymath and inventor. He contributed immeasurably to horological development and to the advancement of other fields including physics, mathematics, biology, astronomy, geology, mechanics, architecture and music. Among his many achievements, he was the first to observe plant cells under a microscope; is credited with inventing cell theory; built vacuum pumps and the earliest Gregorian telescope; inferred a wave theory of light; and observed gravitational properties linked to planetary movement, even contributing ideas to explain heliocentrism. He is famously known for always working on several things in several fields simultaneously. Although not a clockmaker himself, he was also very interested in clocks and is celebrated in horological circles for helping design the balance spring regulator – an addition to the balance wheel that greatly increased the accuracy of portable timepieces.[1] Hooke famously collaborated with clockmaker Thomas Tompion on the invention of the balance spring. For an example of this mechanism, see Tompion’s Striking Clock-watch with alarm and calendar, made around 1677 (and coming soon to Clocktime).[2] According to Hooke’s diaries, he and Tompion met regularly during the time of this clock’s making, and Tompion specifically made use of Hooke’s balance spring design to prevent the watch from striking the incorrect time. Although there is no evidence to confirm that Hooke was involved in the design of this watch, his influence can certainly be felt. Tompion went on to make several watches utilising Hooke’s balance springs around this time. Hooke first met Tompion in 1674. It is believed that Tompion was unhappy with his current instrument maker and was looking for a craftsman to make a quadrant for the Royal Society. Hooke’s diary records several meetings with Tompion and indicates that the quadrant was finished before 5 July 1674. Despite Hooke’s famously prickly nature, the two men seemed to get on well and appear to have enjoyed a long, fruitful professional relationship. There are numerous diary entries in which Hooke records dinners together, as well as casual meetings in the form of day-long visits during which Tompion showed his clockwork to Hooke. It is through Hooke and his Royal Society connections that Tompion was able to meet the distinguished scientists of the day and rub shoulders with royalty and nobility, thus cultivating relationships with his wealthy clientele. Hooke’s well-known irascibility and late-in-life bitterness were based on his belief that he was not being credited or properly compensated for his work. For example, in 1675, Christian Huygens (independently of Hooke) developed his own balance spring and laid claim to the invention for himself – something Hooke vehemently contested. There is another case of uncertainty as to who should receive credit for an innovation. In 1694, John Smith, a working clockmaker of the 1670s, claimed that William Clement was ‘the real contriver of the long pendulum’ (or anchor escapement, as it is known today). This claim has recently been questioned, with Hooke proposed as the true inventor. Hooke’s notes have revealed that he became interested in the properties of gravity and improving upon Huygens’ 1656 invention of the domestic pendulum clock, leading him to develop the design for this mechanism before Clement. Robey even suggests that the development of the rack striking mechanism, widely credited to the Reverend Edward Barlow in 1676, more likely came out of ‘an amalgam of ideas by Barlow, Tompion, (Joseph) Knibb and Hooke’.[3] While at Oxford, Hooke worked as an assistant to the physical scientist Robert Boyle from 1655 to 1662. Immediately following this, in 1662, he was appointed as the Royal Society’s Curator of Experiments in 1662 and then as Professor of Geometry at Gresham College, London in 1664. After a long, varied career, Robert Hooke died on 3 March 1703. End Notes [1] Hall 1950–1951; 1978. [2] Carter 2021, 110–113, Catalogue No. 24; Evans et al. 2013, 267 and 614; Taylor et al. 2019, 24, Exhibit No: 4:1. [3] Robey 2005, 17. References Carter, J. 2021b. The John C Taylor Collection: Part II (Selling Exhibition Catalogue, Carter Marsh & Co.). Winchester: Carter Marsh & Co. Evans, J., J. Carter and B. Wright. 2013. Thomas Tompion – 300 Years: A celebration of the life and work of Thomas Tompion. Walter Lane Publishing. Hall, A. R. 1950–1951. ‘Robert Hooke and horology’ in Notes and Records of the Royal Society of London 8(1): 167–177. Hall, A. R. 1978. ‘Horology and criticism: Robert Hooke’ in Studia Copernicana 16 – Science and History (Ossolinskich): 261–281. Robey, J. March 2005. ‘Who invented rack-and-snail striking? The early development of repeating and rack striking’ in Antiquarian Horology, pp. 1–18. Taylor, J. C. and K. Leith (with contributions by T. Phillipson). 2019. The Luxury of Time: Clocks from 1550–1750. Isle of Man: Fromanteel Ltd. Further Reading Arnol'd V. I. 1990. Huygens and Barrow, Newton and Hooke. Pioneers in mathematical analysis and catastrophe theory from evolvents to quasicrystals. Basel: Birkhäuser. Centore, F. F. 1970. Robert Hooke’s Contributions to Mechanics: A study in seventeenth century natural philosophy. The Hague: Springer. Hesse, M. 1966. ‘Hooke’s vibration theory and the isochrony of springs’ in Isis 57: 433–441. Nichols, R. 1994. The Diaries of Robert Hooke, The Leonardo of London, 1635–1703. University of Michigan: The Book Guild Image Credit Robert Hooke. Pencil drawing by Rita Greer 2006. Rita Greer, FAL, via Wikimedia Commons, https://commons.wikimedia.org/wiki/File:14_Robert_Hooke._Pencil_Drawing.jpg