Robert Hooke: A Life in Five Chapters

Chapter 1 · The Sickly Boy Who Reached Oxford as a Servant

The Isle of Wight to Boyle's air pump

1635 – 1662 · Freshwater · Westminster · Oxford

Robert Hooke was born at Freshwater on the Isle of Wight in July 1635, the son of a curate. He was a sickly child — persistent headaches, and an early illness his family thought would kill him — and was largely left to himself. He drew, and he made mechanical models: a working wooden clock, and a model ship with rigging that fired its guns.

His father died when he was thirteen, leaving him a small sum. He went to London, briefly to the painter Peter Lely, then to Westminster School under Richard Busby, where he learned Euclid, Latin and the organ, and reportedly went through the first six books of the *Elements* in a week.

He reached Christ Church, Oxford, in 1653 as a *servitor* — a student who paid reduced fees by waiting on wealthier undergraduates. He never had money, and the resentment shows in his diary.

At Oxford he found the group around John Wilkins that would become the Royal Society, and became assistant to Robert Boyle. There he built the air pump with which Boyle established the relation between the pressure and volume of a gas. Boyle's law was found on an instrument Hooke designed and made, and Hooke almost certainly did most of the experimental work.

In 1662 the new Royal Society appointed him Curator of Experiments.

Why this matters

Hooke built the air pump on which Boyle's law was established — an early instance of a named law resting on an unnamed instrument-maker's work.

You have the servitor with the mechanical hands. What would you ask him?

Ask Hooke

• “How much of Boyle's law was your work?”
• “What was it like being a servitor among richer students?”
• “What did you build as a boy on the Isle of Wight?”
• “Did you really read six books of Euclid in a week?”
• “How does an air pump actually work?”

Chapter 2 · Three New Experiments Every Week

The job that made and broke him

1662 – 1703 · Gresham College · London

The terms of Hooke's appointment were remarkable and, in retrospect, cruel. As Curator of Experiments he was required to furnish the Royal Society with three or four *new* experiments at every weekly meeting, for as long as he held the post. He held it for about forty years.

Do the arithmetic. That is several thousand demonstrations, on any subject a Fellow happened to be curious about that week: combustion, respiration, gravity, the strength of materials, the propagation of light, the anatomy of a fish, the freezing of water, the behaviour of a barometer.

The consequences run through everything about him. It explains his range, which is unmatched by anybody in the period. It explains his lack of finish: an idea that would have taken a year to develop properly got a week, because the following Wednesday needed three more. And it explains his fury about priority — he had genuinely *had* a great many ideas first, in a room full of witnesses, and watched other men develop them at leisure.

He was also, from 1665, Professor of Geometry at Gresham College, where he lived in a set of rooms for the rest of his life, with his niece Grace Hooke as his household companion. His diary records that relationship in terms which modern readers find deeply uncomfortable, and it should not be smoothed over.

He was, by every account including his own, difficult: suspicious, quick to take offence, and often right about being cheated.

“By the help of microscopes, there is nothing so small as to escape our inquiry.”

— Robert Hooke, Micrographia (1665), Preface

Why this matters

Hooke's contract required perpetual novelty, which produced unmatched range and chronic incompleteness — a structural explanation for a career usually blamed on temperament.

You have the weekly demand for novelty. What is your question?

Ask Hooke

• “How did you find three new experiments every single week?”
• “What did that job cost your best ideas?”
• “Were you right to be so suspicious about priority?”
• “Which of your weekly demonstrations should have been a book?”
• “What did the Fellows actually want to see?”

Chapter 3 · Micrographia

A flea the size of a cat, and a word that founded biology

1665 · London

*Micrographia*, published in January 1665, was the Royal Society's first major publication and one of the most successful scientific books ever printed. Samuel Pepys sat up until two in the morning with it and called it the most ingenious book he had ever read.

Its power is visual. Hooke drew what he saw through the microscope and had it engraved on fold-out plates at enormous scale: a flea rendered a foot long, its armour plating and bristles fully articulated; the compound eye of a grey drone fly; a louse gripping a human hair; the point of a needle, which under magnification is a battered lump, and the edge of a razor, which is a ragged saw. That last observation is the book's quiet argument — that human workmanship looks crude beside nature's, and that the unaided eye is a poor witness.

Examining a thin sliver of cork, he saw it divided into rows of small empty boxes, regular as a honeycomb. He counted them: over a thousand million in a cubic inch. He called them *cells*, after the small bare rooms of a monastery.

He was looking at the dead cell walls of plant tissue, not at living cells, and he had no notion that all organisms are made of them — cell theory arrived with Schleiden and Schwann in 1838 and 1839. But the word is his, and it is now one of the load-bearing words in biology.

The book also contains a wave theory of light, observations of the coloured fringes in thin films, and the argument that fossils are the remains of creatures that no longer exist.

Why this matters

Hooke named the cell while looking at empty walls in dead cork, and the word outlived every idea he attached to it.

You have the flea, the razor's edge and the boxes in the cork. What would you ask?

Ask Hooke

• “Why call them cells?”
• “Did you understand what you were actually looking at in the cork?”
• “Why draw the flea a foot long?”
• “What is the point of showing a razor's edge is ragged?”
• “Why did you say fossils were once alive?”

Chapter 4 · As the Extension, So the Force

An anagram, and a city to rebuild

1666 – 1678 · London

Hooke found that when you stretch a spring, the extension is proportional to the force applied. Double the load, double the stretch. It holds for springs, wires and beams, up to a limit beyond which the material deforms permanently.

He published it in 1676 — as an anagram: *ceiiinosssttuv*. Two years later he supplied the solution: *ut tensio, sic vis*, as the extension, so the force.

The anagram was a device of the period for claiming priority without disclosing a result you were still exploiting commercially — Hooke was working on spring-regulated watches, disputing the invention with Huygens. It also meant that for two years nobody could use, test or build on his law. It is a small case study in what secrecy does.

Meanwhile the Great Fire of September 1666 destroyed most of the City of London. Hooke produced a plan for rebuilding within days, was appointed one of the City Surveyors, and spent years on it — surveying burnt plots, settling boundary disputes between neighbours, and designing buildings.

He worked closely with Christopher Wren, and the division of credit between them is genuinely unclear. The Monument to the Great Fire is substantially Hooke's, designed to double as a zenith telescope with a laboratory in the base. The Royal College of Physicians and Bethlem Hospital were his. Much of what is credited to Wren was collaborative.

This was also the work that made him money. He died wealthy, with a chest of coins in his rooms.

Why this matters

Hooke's law is the foundation of the mechanics of materials, and publishing it as an anagram delayed its use by two years — a concrete cost of scientific secrecy.

You have the anagram and the burnt city. What is your question?

Ask Hooke

• “Why publish your law as an anagram?”
• “Where does Hooke's law stop working?”
• “How much of Wren's London is actually yours?”
• “What was surveying the burnt plots like?”
• “Why build a telescope into the Monument?”

Chapter 5 · The Quarrel He Lost, and the Face Nobody Has

An inverse square without the mathematics

1679 – 1703 and after · London · Cambridge

In 1679 Hooke, then Secretary of the Royal Society, wrote to Newton proposing that planetary motion could be explained by an attraction toward the Sun falling off as the inverse square of the distance, combined with a body's tendency to move in a straight line.

That is essentially right, and Hooke could not prove it. He had no mathematics capable of showing that such a force produces an elliptical orbit. Newton had, and did, and the *Principia* appeared in 1687 with no acknowledgement of Hooke.

Hooke demanded credit. Newton's response was to threaten to withdraw the third book, and to strike out most references to Hooke. Their earlier quarrel over the nature of light — Hooke had claimed Newton's 1672 optics paper borrowed from *Micrographia* — had already poisoned everything; the famous line about standing on the shoulders of giants comes from a letter to Hooke, who was short and stooped, and its sincerity has been argued about ever since.

Hooke's position is defensible: having the idea is not nothing. Newton's is also defensible: without the proof, the idea is a conjecture. They were both partly right and neither would concede.

Hooke died on 3 March 1703. Newton became President of the Royal Society the same year. The Society's only known portrait of Hooke disappeared during its move to new premises, and no authenticated likeness survives anywhere — the only major figure of the Scientific Revolution of whom this is true. Whether Newton was responsible is unproven and widely suspected.

Why this matters

The Hooke–Newton dispute is the clearest test case in science of whether a correct idea without a proof deserves credit alongside the proof.

You have the conjecture, the proof and the missing portrait. What would you ask?

Ask Hooke

• “Does proposing the inverse-square law without proving it earn you credit?”
• “Why could you not supply the mathematics yourself?”
• “Was Newton's line about giants aimed at you?”
• “How would you have handled the quarrel differently?”
• “Does it trouble you that no portrait of you survives?”

What Hooke changed

Hooke's law underlies the whole physics of materials, and the word 'cell' he coined for the empty boxes in cork became one of the foundational terms of biology. Micrographia showed the public what instruments could reveal and remains one of the most beautiful scientific books ever made. He rebuilt a substantial part of London after the Great Fire, and proposed the inverse-square law of gravitation before the Principia without being able to prove it.

A debate that continues

The division of credit between Hooke and Newton over the inverse-square law, and between Hooke and Wren over the rebuilding of London, are both genuinely unsettled. No authenticated portrait of Hooke survives, and whether Newton had a hand in its loss is suspected but unproven.

Keep exploring — ask Hooke

• “Which of your unfinished ideas would you go back to?”
• “Is an idea worth anything without the proof?”
• “What should the Royal Society have done differently by you?”

Related lives

• Isaac Newton — Lucasian Professor · President of the Royal Society
• Antonie van Leeuwenhoek — Who Found A World In A Drop Of Water
• Robert Boyle — Who Emptied a Jar and Silenced a Bell
• Christiaan Huygens — Who Watched From A Moving Boat

Related themes

Cells and microscopy · Forces and springs · Priority and credit in science