Restoration man
Volume 15 Number 3, Trinity 2003
Apart from those who may have spotted a twentieth-century plaque set into the wall of University College on the High, recounting his alleged discovery of 'the living cell', and vague recollections from school physics that he did something with springs, most people will never have heard of Robert Hooke. It is all the more important, therefore, that in this 300th anniversary year of Hooke's death on 3 March 2003, we should remember a man who was not just an eminent Oxford scientist, but a figure without whose remarkable ingenuity the world of science could well have been a quite different place.
Hooke was an original figure in so many ways. While he was by no means the first post-classical scientist - after all, Galileo, William Harvey, and the great geographical discoverers had all published their researches by the time Hooke was born on 18 July 1635 - he brought ideas into science that have fundamentally shaped the modern world. For one thing, he realised that our natural senses of sight and touch are just too crude to penetrate into the inner structures of nature. We needed to devise 'artificial organs' to strengthen them - by which Hooke meant scientific instruments. And having perfected increasingly accurate telescopes, microscopes, barometers and so on, we should then use them to subject nature to a series of controlled experiments. For all scientific knowledge, Hooke reminded his readers, comes from our five senses, and the more acute we can make these senses, the more we can discover.
Yet when Hooke came up to Christ Church from Westminster School in 1653, the son of a curate of Freshwater on the Isle of Wight, this experimental approach to knowledge was regarded as novel in the extreme. Indeed, according to Hooke's lifelong Trinity College friend, the diarist and raconteur John Aubrey, 'Till about the yeare 1649, when Experimental Philosophy was first cultivated by a Club at Oxford, 'twas held a strange presumption for a man to attempt an Innovation in Learnings; and not to be good Manners, to be more knowing than his Neighbours and Forefathers.'
This Oxford Philosophical, or Scientific, Club had been started by the Revd Dr John Wilkins, Warden of Wadham, and in 1660 it moved to London, where it became the Royal Society. Hooke seems to have become involved with Wilkins's Club almost as soon as he arrived in Oxford, and one wonders if he had perhaps been talent-spotted while still at Westminster, where he had won schoolboy fame by devising flying machines as well as mastering Euclid, music and the classical languages in record time.
Because he came up to Christ Church at a time when the Puritans controlled the University, and efforts were made to erase as much as possible of their memory after the Royalist Restoration in 1660, scarcely any formal University record of Hooke's undergraduate years remains. He was described by Aubrey, however, as enjoying a 'Chorister's place' at Christ Church, and living in the same set of rooms as those in which Robert Burton, author of The Anatomy of Melancholy, had both resided and committed suicide. Indeed, Hooke does not seem to have been properly matriculated until 1658 - when he is described as 'fil. min.' (filius minor), or younger son. Nor does he seem to have taken a BA degree. By 1663, however, his reputation was such that he was granted his MA 'by the Favour of the Chancellor'. And in that same year, he was elected Fellow of the Royal Society, having recently moved to London to become Curator of Experiments to the Society.
But it was in Dr Wilkins's Club that met in Wadham on Wednesday afternoons that the gifted Christ Church undergraduate won both encouragement and employment. As he later told his obituarist Richard Waller, by 1655 he was being urged by Dr Seth Ward, Savilian Professor of Astronomy, to make astronomical observations with telescopes, he and Wilkins were devising flying machines in Wadham gardens, and he had already embarked on those physics researches that led to his invention of the balance spring of watches. One of Hooke's first profound and far-reaching insights into nature had occurred around 1657, when he recognised that the energy which made a pendulum swing in equal periods of time was related to the energy needed to tension and release a steel spring. So if it was possible to control the swinging balance of a mechanical watch by a fine hair spring, it should also be possible to make the watch keep accurate time. Hooke's 'pendulum watches' were one of the very first applications of a discovery in pure physics to practical, everyday technology, and the use of the hair spring in portable timekeepers continued down to the invention of quartz watches in our own time.
It was also in Oxford that Robert Hooke formed a lifelong friendship with the young Christopher Wren of Wadham. Wren, who came from a distinguished Wiltshire clerical and landowning family, was three years older than Hooke, and was already recognised as a man of brilliance when their friendship began. Hooke always spoke of Wren, who was also a member of Dr Wilkins's circle, as one of his mentors. Both men shared a passion for the 'new' knowledge of science and its applications, and exchanged ideas on subjects as diverse as astronomy, anatomy, instrument design and architecture.
And when, in the aftermath of the Great Fire of London in 1666, Wren was appointed as the King's Surveyor and Hooke as the City of London's Surveyor, they collaborated closely on projects such as the Royal Observatory, Greenwich (1675), and the Monument (1678) in Fish Street Hill. Both men hoped to use the Monument as an astronomical observatory.
If Wilkins, Ward and Wren helped to form Hooke as a physicist and astronomer, two other Oxford influences lay at the heart of his chemical and physiological ideas. Research in the life sciences in Hooke's younger days was dominated by William Harvey's 1628 discovery that the blood, instead of simply travelling on a one-way journey from the heart to the body's extremities to convey heat and nourishment, actually circulated around the body. It circulated, indeed, under the mechanical action of the heart, for Harvey had realised that the heart was not a furnace, as Aristotle had taught, but a pump.
The great agenda set for 17th-century physiologists was to work out in detail how this circulation acted and, in particular, how the arterial blood became bright red after passing through the lungs. Dr Thomas Willis of Christ Church, a leading Oxford physician, employed Hooke as an assistant in around 1656-8, and it was almost certainly from Willis that Hooke learned those skills as a dissector and animal experimenter that he displayed so brilliantly before the Royal Society in 1667 in the insufflation experiments, which demonstrated the role played by air in the blood-colour changes in the lungs.
It is also likely that it was from Willis that Hooke's interests in the physiology of perception were first aroused, for Willis was a pioneer of brain anatomy, who in 1664 coined the word 'neurology' for the scientific study of the brain. At several stages in his subsequent career, moreover, Hooke speculated about how such things as sound and colour sensation, along with memory, were related to those cerebral regions that Willis and other anatomists had shown to have direct nerve connections to the ears and eyes.
In 1658, Hooke started to work for the Hon Robert Boyle, an Irishman who was one of the leading chemists in Europe, and currently resident at Deep Hall, in the High - a large house whose site is now occupied by the extension of University College to which the commemorative plaque is fixed. Boyle was one of the founders of combustion chemistry, who was beginning to doubt the classical Greek idea that fire was an 'element', or a primary force of nature. Instead, it seemed to him, burning was a chemical process. At Boyle's behest, Hooke designed and built the first modern laboratory air pump, and found that the vacuum it produced had strange properties. Cats, birds and reptiles died in vacuums. Candles went out in them, and could not be relit, even when sunlight was focused on their wicks with a burning glass. Yet while gunpowder would not explode in vacuo, it would nevertheless fizzle and burn when hot sparks were dropped on to it. Was there something within the saltpetre (potassium nitrate) ingredient of gunpowder that contained its own air supply?
This thought led Hooke and Boyle to develop the idea of aerial nitre, to describe a part of the air that was 'corrosive' or capable of inflaming things. This nitrous part of the air, moreover, seemed to be involved in making dark blood turn bright red once again when inhaled into the lungs. Dr John Mayow, of Wadham, another Wilkins protégé, later developed their work on the physiology of respiration, and by 1674 had obtained a remarkably good approximation for what we now know to be nitrogen and carbon dioxide (inert) and oxygen (combustive) parts of the air.
Of course, no one thought in terms of what we now see as chemically specific gases in 1660, and oxygen was not to be identified in its modern chemical sense for another century. However, what Hooke and Boyle had discovered at Deep Hall was that breathing and burning were chemically related, and that the nitrous part of the air was common to both.
It is hard to imagine that the young Hooke was not present at those extraordinary experiments undertaken in Oxford by Wren, Wilkins, Willis and Boyle after 1656, when they discovered that a mixture of wine and opium, injected directly into the vein of a dog, made the poor brute comatose much faster than when the drug was administered orally. On one occasion, they had to chase the stupefied animal around the garden for over half an hour to prevent it falling into a fatal stupor. The thought of half a dozen gowned gentlemen chasing a staggering hound around Wadham gardens must surely be one of the enduring images of the scientific revolution!
The nine years that Hooke spent in Oxford were utterly formative in his career as Britain's first formally salaried research scientist, which he began on becoming Curator of Experiments to the Royal Society in 1662 and continued as Professor of Geometry at Gresham College, London, in 1665. His subsequent work on microscopy, astronomy, optics and several other experimental sciences demonstrated that our knowledge of the inner structures of nature could advance at an astonishing rate once we started to make our senses progressively more acute by equipping them with 'artificial organs'.
Robert Hooke died a bachelor at the age of 67 on 3 March 1703, at Gresham College. Yet transcending all the discoveries and insights made across 50 years, his consummate achievement lay in showing that the experimental scientific method really worked, and could transform our understanding of nature - and this Hooke learned in Oxford.