Robert Hooke
Robert Hooke,
FRS (
July 18,
1635 â€"
March 3,
1703) was an
English polymath who played an important role in the
scientific revolution, through both experimental and theoretical work. His father was John Hooke curate of the Church of All Saints, Freshwater.
Born in
Freshwater on the
Isle of Wight, Hooke received his early education on the Isle of Wight and, from about the age of 13, at
Westminster School under Dr. Busby. In
1653, Hooke secured a chorister's place at
Christ Church,
Oxford. There he met the chemist (and physicist)
Robert Boyle, and gained employment as his assistant. It is possible that Hooke formally stated
Boyle's Law, as Boyle was not a mathematician. In
1660, he discovered
Hooke's law of
elasticity, which describes the linear variation of
tension with extension in an
elastic spring. In
1662, Hooke gained appointment as Curator of Experiments to the newly founded
Royal Society, and took responsibility for experiments performed at its meetings. In
1665 he published a book entitled
Micrographia, which contained a number of
microscopic and
telescopic observations, and some original
biology. Indeed, Hooke coined the biological term
cell -- so called because his observations of plant cells reminded him of
monks' cells which were called "cellula". He is often credited with the discovery of the cell, though his microscope was very basic. The hand-crafted, leather and gold-tooled microscope Hooke used to make these observations for "Micrographia," is on display at the National Museum of Health and Medicine in Washington, DC. Also in 1665 he gained appointment as Professor of
Geometry at
Gresham College.
Robert Hooke also achieved fame as Surveyor to the City of London and chief assistant of
Christopher Wren, helping to rebuild London after the
Great Fire in
1666. He worked on designing the
Monument,
Royal Greenwich Observatory and the infamous
Bethlem Royal Hospital (which became known as 'Bedlam').
He died in
London on 3 March 1703 (ns). He amassed a sizeable sum of money during his career in London, which was found in his room at Gresham College after his death. He never married.
It seems that no authenticated portrait of him survives. In 2003 the historian
Lisa Jardine claimed a recently discovered portrait represents Robert Hooke. However, Prof. Jardine's hypothesis was soon disproved by Prof.
William Jensen (University of Cincinnati) and independently by the German researcher
Andreas Pechtl (Johannes Gutenberg University, Mainz). Actually, the portrait represents
Jan Baptist van Helmont. A seal used by Hooke displays an unusual profile portrait of a man's head, that some have argued portrays Hooke. Both these claims remain in dispute, however. Moreover, the engraved frontispiece to the 1728 edition of Chambers' Cyclopedia shows as an interesting detail the bust of Robert Hooke.
In addition to the book
Micrographia and Hooke's Law, Hooke invented the
anchor escapement and may also have invented the
balance spring before
Christiaan Huygens. Devices known as escapements regulate the rate of a
watch or
clock, and the anchor escapement represented a major step in the development of accurate watches. The balance spring also regulates the flow of energy from the mainspring of a timepiece. It coils and uncoils with a natural periodicity, allowing for fine adjustment of the period of ticks. Modern spring watches still use balance springs, and derivative designs of Hooke's
anchor escapement remain in common use. In February
2006, a long-lost copy of Hooke's handwritten notes from several decades'
Royal Society meetings was discovered in a cupboard in Hampshire, and the balance-spring controversy appears by evidence contained in those notes to be settled in favor of Hooke's claim.
Historians sometimes credit Hooke with inventing the
compound microscope, a design consisting of multiple lenses (usually three â€" an eyepiece, a field lens and an objective). While he did give much advice on new microscope designs to the instrument-maker
Christopher Cock, this attribution appears incorrect, since
Zacharias Janssen had already assembled compound microscopes in
1590. However, Hooke's microscopes achieved 30x magnification, which far outstripped the capabilities of any previous instruments. Hooke once called his compound microscopes "offensive to my eye" and "much strained and weakened the sight". Leeuwenhoek found his animalcules and Hooke was asked to confirm his findings.
Hooke's other significant achievements include the construction of the first
Gregorian reflecting telescope, the law of elasticity, and the discovery of the first
binary star. He also receives credit with inventing the first practical
universal joint, sometimes called the Hooke joint, although the Italian mathematician
Girolamo Cardano had proposed the idea about a century earlier and may or may not have built one.
Hooke also experimentally demonstrated the inverse-square law of gravity, but did not prove it mathematically.
Hooke has been described as London's Leonardo (Bennett 2003) because of the breadth of his interests and the volume of his output which included not only science but architecture, surveying, town planning and invention.
Some of Hooke's significant achievements in science
* First to refer to
cells in living matter. 1665: Robert Hooke discovers
cells in cork, then in living plant tissue using an early
microscope.
* First to study
fossils and hypothesise that they were extinct species.
* First to report
Jupiter's
Red Spot and by observing it deduce that the planet rotated.
* First to report the rotation of Mars.
* Worked out the number of vibrations of each
musical note.
* Observed Lunar
craters.
* Published the first book on
microscopy,
Micrographia.
* First to explain the shape of crystal in terms of the packing of their component parts.
* One of the first to observe a
binary star.
* Postulated a
wave theory of
light, rejected by Newton and not re-established until about
1820 by
Fresnel.
* Advocated the medicinal use of
Indian Hemp.
* Proposed the
inverse square relationship for gravity.
* Proposed to Newton the idea that planetary motion was a combination of linear and circular motion. It is this that is far more important for Newton's work than the inverse square law.
* Devised Hooke's law of springs and stretching.
* His investigations into
combustion that came close to discovering
oxygen 100 years before
Lavoisier.
Inventions
Like many scientists of the
Early Modern era Hooke was also a prolific inventor. Some of Hooke's inventions that are still in use:
* The first
anemometer.
* The first recording weather station.
* A
thermometer.
* The
universal joint.
* The
spirit level.
* The use of
rhumb lines to navigate a
great circle route.
* The
compound microscope.
* The first
Gregorian telescope.
* Developed the
air pump for
Boyle.
* The spring driven clock and spring
balance wheel.
* The
anchor escapement for clocks.
* The
iris diaphragm used in cameras.
* Telescope
crosshair sight.
* The
sash window.
Robert Hooke and
Isaac Newton entertained a considerable mutual dislike for each other. They fell out in
1672 when Hooke criticized Newton's presentation showing that
prisms split white
light rather than modifying it. (Hooke, unlike many others, had been able to reproduce Newton's prism experiments and so spoke with some authority.) Newton expressed fury that Hooke seemed unable to grasp his ground-breaking discovery, and threatened to leave the Royal Society.
Relations between the men grew worse as time progressed. In
1679, Hooke wrote to Newton advocating an
inverse square law of
gravitation. He had probably discovered the relationship before 1660 but lacked the mathematical ability to formally prove it. When Newton published his
Philosophiae Naturalis Principia Mathematica in
1687, including a proof of an inverse square law, he failed to credit Hooke at all despite initially having included acknowledgement of Hooke in the manuscript.
It is possible that this dispute may be overplayed:
Gunther suggests that the two men held each other in some regard until quite late, citing as evidence their correspondence over matters such as the inverse-square law of gravitation, which Hooke (an undoubtedly gifted experimenter) had demonstrated. On the other hand Newton appears to have delayed publication of his
Opticks until after Hooke's death for fear of Hooke's reaction to its contents.
The famous Newton quote,
"If I have seen further, it is by standing on the shoulders of giants," appeared originally in a letter to Hooke, and this has been interpreted as a sarcastic remark directed against Hooke. This is somewhat speculative: Hooke and Newton had exchanged many letters in tones of mutual regard, and Hooke was not of particularly short stature, although he was of slight build and had been afflicted from his youth with a severe stoop.
At a time when science was progressing by leaps and bounds it was inevitable that two men with such similar interests would come up with similar ideas. Whether Hooke or Newton first invented the reflecting telescope is a matter of conjecture, but it is the case that Hooke did demonstrate what is now known as the Newtonian telescope some time before Newton is credited with inventing it, as well as documenting "
Newton's rings" before Newton did.
Newton's animosity towards Hooke extended to the removal of Hooke's portrait in the Royal Society and an attempt (prevented) to have Hooke's papers in the Society burned. Some have argued that Hooke's own unsympathetic character was also a factor: his diary shows that he did have uncomplimentary words for a number of the men he worked with, and was long in dispute with Huygens. Inwood (2002) points out that Hooke enjoyed a very active social life in the
coffee houses of London and was known to have many close friends such as
Christopher Wren. On this basis he appears to have been far more sociable and gregarious than Newton who spent much of his life as an academic recluse in Cambridge.
 |
The church at Willen, Milton Keynes (backlit by morning sun) |
Robert Hooke was an important architect. He was the official London Surveyor after the
Great Fire of 1666, surveying about half the plots in the city. As well as the
Bethlem Royal Hospital, other buildings designed by Hooke include: The
Royal College of Physicians (1679);
Ragley Hall in
Warwickshire; and the parish church at
Willen,
Milton Keynes (
historical Buckinghamshire).
Hooke's collaboration with
Christopher Wren was particularly fruitful and yielded The Royal Observatory at Greenwich,
The Monument (to the Great Fire) and
St Paul's Cathedral, whose dome uses a method of construction conceived by Hooke.
In the reconstruction after the Great Fire, Hooke proposed redesigning London's streets on a grid pattern with wide boulevards and arteries along the lines of the
Champs-Élysées, (this pattern was subsequently used for Liverpool and many American cities), but was prevented by problems over property rights. Many property owners were surreptitiously shifting their boundaries and disputes were rife. (Hooke was in demand to use his competence as a surveyor and tact as an arbitrator to settle many of these disputes.) So London was rebuilt along the original mediaeval streets. It is interesting to note that the modern-day curse of congestion in London has its origin in petty disputes in the 17th Century.
Robert Hooke is one of many real-life personages featured in the historical adventure novels
The Baroque Cycle by American author
Neal Stephenson; Hooke's skill in the sciences and surgical arts are used to great (and often darkly comedic) effect throughout the cycle.
*
The Man Who Knew Too Much, Stephen Inwood, Pan Books, 2002. ISBN 0330488295. (Published in the USA as
The Forgotten Genius)
*
Early Science in Oxford vol vii,
Dr. R. T. Gunther, ed., privately printed, 1923-67.
*
Robert Hooke, Margaret 'Espinasse.
William Heinemann Ltd, 1956.
*
The Curious Life of Robert Hooke: The Man who Measured London,
Lisa Jardine. Harper Collins Publishers, 2003. ISBN 0007149441.
*
London's Leonardo: The Life and Work of Robert Hooke,
Jim Bennett, Michael Cooper, Michael Hunter and
Lisa Jardine.
Oxford University Press, 2003. ISBN 0198525796.
*
England's Leonardo: Robert Hooke and the Seventeenth-century Scientific Revolution,
Allan Chapman.
Institute of Physics Publishing, 2004. ISBN 0750309873.
*
Robert Hooke and the English Renaissance,
Allan Chapman and Paul Kent (editors). Gracewing, 2005. ISBN 0852445873.
* Hooke, Robert (1635-1703).
Micrographia: or some physiological descriptions of minute bodies made by magnifying glasses with observations and inquiries thereupon...*
List of astronomical instrument makers*
roberthooke.org.uk*
Free ebook of Robert Hooke at
Project Gutenberg*
Hooke Timeline*
England's Leonardo lecture on Robert Hooke
*
[1] engraved bust of Robert Hooke
*
Robert Boyle and Robert Hooke*
Lost manuscript of Robert Hooke discovered â€" from
The Guardian
