John Ambrose Fleming
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Sir John Ambrose Fleming (29 November 1849 – 18 April 1945) was an English
electrical engineer Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems that use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the l ...
who invented the
vacuum tube A vacuum tube, electron tube, thermionic valve (British usage), or tube (North America) is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. It ...
, designed the
radio transmitter In electronics and telecommunications, a radio transmitter or just transmitter (often abbreviated as XMTR or TX in technical documents) is an electronic device which produces radio waves with an antenna with the purpose of signal transmissio ...
with which the first transatlantic radio transmission was made, and also established the
right-hand rule In mathematics and physics, the right-hand rule is a Convention (norm), convention and a mnemonic, utilized to define the orientation (vector space), orientation of Cartesian coordinate system, axes in three-dimensional space and to determine the ...
used in
physics Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...
. He was born in Lancaster, Lancashire and was baptised on 11 February 1850, the eldest of seven children of James Fleming DD (died 1879), a
Congregational Congregationalism (also Congregational Churches or Congregationalist Churches) is a Reformed Christianity, Reformed Christian (Calvinist) tradition of Protestant Christianity in which churches practice Congregationalist polity, congregational ...
minister, and his wife Mary Ann. A devout Christian, he once preached at
St Martin-in-the-Fields St Martin-in-the-Fields is a Church of England parish church at the north-east corner of Trafalgar Square in the City of Westminster, London. Dedicated to Saint Martin of Tours, there has been a church on the site since at least the medieval pe ...
in London on evidence for the
resurrection Resurrection or anastasis is the concept of coming back to life after death. Reincarnation is a similar process hypothesized by other religions involving the same person or deity returning to another body. The disappearance of a body is anothe ...
. In 1932, he and Douglas Dewar and Bernard Acworth helped establish the Evolution Protest Movement. Fleming bequeathed much of his estate to Christian charities, especially those for the poor. He was a noted photographer, painted watercolours, and enjoyed climbing the
Alps The Alps () are some of the highest and most extensive mountain ranges in Europe, stretching approximately across eight Alpine countries (from west to east): Monaco, France, Switzerland, Italy, Liechtenstein, Germany, Austria and Slovenia. ...
.


Early years

Ambrose Fleming was born in Lancaster and educated at
Lancaster Royal Grammar School Lancaster Royal Grammar School (LRGS) is an 11–18 boys grammar school in Lancaster, England, Lancaster, Lancashire, England. Old students belong to The Old Lancastrians. The school's sixth form opened to girls in 2019. LRGS is also in the Unit ...
, University College School, London, and then
University College London University College London (Trade name, branded as UCL) is a Public university, public research university in London, England. It is a Member institutions of the University of London, member institution of the Federal university, federal Uni ...
, where he obtained a BSc in 1870. He entered
St John's College, Cambridge St John's College, formally the College of St John the Evangelist in the University of Cambridge, is a Colleges of the University of Cambridge, constituent college of the University of Cambridge, founded by the House of Tudor, Tudor matriarch L ...
in 1877, gaining a DSc from the
University of London The University of London (UoL; abbreviated as Lond or more rarely Londin in Post-nominal letters, post-nominals) is a collegiate university, federal Public university, public research university located in London, England, United Kingdom. The ...
in 1879 and a BA from Cambridge in 1881, before becoming a fellow of St John's in 1883. He went on to lecture at several universities including the
University of Cambridge The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...
, University College Nottingham, and University College London, where he was the first professor of electrical engineering. He was also a consultant to the Marconi Wireless Telegraph Company, Swan Company,
Ferranti Ferranti International PLC or simply Ferranti was a UK-based electrical engineering and equipment firm that operated for over a century, from 1885 until its bankruptcy in 1993. At its peak, Ferranti was a significant player in power grid system ...
, Edison Telephone, and later the Edison Electric Light Company. In 1892, Fleming presented an important paper on electrical
transformer In electrical engineering, a transformer is a passive component that transfers electrical energy from one electrical circuit to another circuit, or multiple Electrical network, circuits. A varying current in any coil of the transformer produces ...
theory to the
Institution of Electrical Engineers The Institution of Electrical Engineers (IEE) was a British professional organisation of electronics, electrical, manufacturing, and information technology professionals, especially electrical engineers. It began in 1871 as the Society of Tel ...
in London.


Education and marriages

Fleming started school at about the age of ten, attending a private school where he particularly enjoyed
geometry Geometry (; ) is a branch of mathematics concerned with properties of space such as the distance, shape, size, and relative position of figures. Geometry is, along with arithmetic, one of the oldest branches of mathematics. A mathematician w ...
. Prior to that his mother tutored him and he had learned, virtually by heart, a book called the ''Child's Guide to Knowledge'', a popular book of the day – even as an adult he would quote from it. His schooling continued at the University College School where, although accomplished at maths, he habitually came bottom of the class at
Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
. Even as a boy he wanted to become an engineer. At 11 he had his own workshop where he built model boats and engines. He even built his own camera, the start of a lifelong interest in photography. Training to become an engineer was beyond the family's financial resources, but he reached his goal via a path that alternated education with paid employment. Fleming enrolled for a BSc degree at
University College London University College London (Trade name, branded as UCL) is a Public university, public research university in London, England. It is a Member institutions of the University of London, member institution of the Federal university, federal Uni ...
, graduated in 1870, and studied under the mathematician
Augustus De Morgan Augustus De Morgan (27 June 1806 – 18 March 1871) was a British mathematician and logician. He is best known for De Morgan's laws, relating logical conjunction, disjunction, and negation, and for coining the term "mathematical induction", the ...
and the physicist George Carey Foster. He became a student of chemistry at the Royal College of Science in
South Kensington South Kensington is a district at the West End of Central London in the Royal Borough of Kensington and Chelsea. Historically it settled on part of the scattered Middlesex village of Brompton. Its name was supplanted with the advent of the ra ...
in London (now Imperial College). There he first studied
Alessandro Volta Alessandro Giuseppe Antonio Anastasio Volta (, ; ; 18 February 1745 – 5 March 1827) was an Italian chemist and physicist who was a pioneer of electricity and Power (physics), power, and is credited as the inventor of the electric battery a ...
's battery, which became the subject of his first scientific paper. This was the first paper to be read to the new Physical Society of London (now the
Institute of Physics The Institute of Physics (IOP) is a UK-based not-for-profit learned society and professional body that works to advance physics education, physics research, research and applied physics, application. It was founded in 1874 and has a worldwide ...
) and appears on page one of volume one of their Proceedings. Financial problems again forced him to work for a living and in the summer of 1874 he became science master at
Cheltenham College Cheltenham College is a public school ( fee-charging boarding and day school for pupils aged 13–18) in Cheltenham, Gloucestershire, England. The school opened in 1841 as a Church of England foundation and is known for its outstanding linguis ...
, a public school, earning £400 per year. (He later also taught at
Rossall School Rossall School is a private Day school, day and boarding school, boarding school in the United Kingdom for 0–18 year olds, between Cleveleys and Fleetwood, Lancashire. Rossall was founded in 1844 by St. Vincent Beechey, St Vincent Beechey as a ...
.) His own scientific research continued and he corresponded with
James Clerk Maxwell James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish physicist and mathematician who was responsible for the classical theory of electromagnetic radiation, which was the first theory to describe electricity, magnetism an ...
at
Cambridge University The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...
. After saving £400, and securing a grant of £50 a year, in October 1877 at the age of 27, he once again enrolled as a student, this time at
Cambridge Cambridge ( ) is a List of cities in the United Kingdom, city and non-metropolitan district in the county of Cambridgeshire, England. It is the county town of Cambridgeshire and is located on the River Cam, north of London. As of the 2021 Unit ...
. He was among the "two or perhaps three University students who attended
Maxwell Maxwell may refer to: People * Maxwell (surname), including a list of people and fictional characters with the name ** James Clerk Maxwell, mathematician and physicist * Justice Maxwell (disambiguation) * Maxwell baronets, in the Baronetage of N ...
's last Course". Maxwell's lectures, he admitted, were difficult to follow. Maxwell, he said, often appeared obscure and had "a paradoxical and allusive way of speaking". On occasions Fleming was the only student at those lectures. Fleming again graduated, this time with a
First Class Honours The British undergraduate degree classification system is a grading structure used for undergraduate degrees or bachelor's degrees and integrated master's degrees in the United Kingdom. The system has been applied, sometimes with significant var ...
degree in chemistry and physics. He then obtained a DSc from London and served one year at
Cambridge University The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...
as a demonstrator of mechanical engineering before being appointed as the first Professor of
Physics Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...
and Mathematics at University College Nottingham, but he left after less than a year. On 11 June 1887, he married Clara Ripley (1856/7–1917), daughter of Walter Freake Pratt, a solicitor from
Bath Bath may refer to: * Bathing, immersion in a fluid ** Bathtub, a large open container for water, in which a person may wash their body ** Public bathing, a public place where people bathe * Thermae, ancient Roman public bathing facilities Plac ...
. On 27 July 1928 he married the popular young singer Olive May Franks (b. 1898/9), of
Bristol Bristol () is a City status in the United Kingdom, cathedral city, unitary authority area and ceremonial county in South West England, the most populous city in the region. Built around the River Avon, Bristol, River Avon, it is bordered by t ...
, daughter of George Franks, a
Cardiff Cardiff (; ) is the capital city, capital and List of urban areas in the United Kingdom, largest city of Wales. Cardiff had a population of in and forms a Principal areas of Wales, principal area officially known as the City and County of Ca ...
businessman.


Activities and achievements

After leaving the
University of Nottingham The University of Nottingham is a public research university in Nottingham, England. It was founded as University College Nottingham in 1881, and was granted a royal charter in 1948. Nottingham's main campus (University Park Campus, Nottingh ...
in 1882, Fleming took up the post of "electrician" to the Edison Electrical Light Company, advising on lighting systems and the new
Ferranti Ferranti International PLC or simply Ferranti was a UK-based electrical engineering and equipment firm that operated for over a century, from 1885 until its bankruptcy in 1993. At its peak, Ferranti was a significant player in power grid system ...
alternating current systems. In 1884 Fleming joined University College London taking up the Chair of Electrical Technology, the first of its kind in England. Although this offered great opportunities, he recalls in his autobiography that the only equipment provided to him was a blackboard and piece of chalk. In 1897 the Pender Laboratory was founding at University College London and Fleming took up the Pender Chair after the £5000 was endowed as a memorial to
John Pender Sir John Pender KCMG GCMG FSA FRSE (10 September 1816 – 7 July 1896) was a Scottish submarine communications cable pioneer and politician. Early life Pender was born in the Vale of Leven, Scotland, the son of James Pender and his wife, Mar ...
, the founder of Cable and Wireless. In 1899
Guglielmo Marconi Guglielmo Giovanni Maria Marconi, 1st Marquess of Marconi ( ; ; 25 April 1874 – 20 July 1937) was an Italian electrical engineer, inventor, and politician known for his creation of a practical radio wave-based Wireless telegraphy, wireless tel ...
, the inventor of radiotelegraphy, decided to attempt transatlantic radio communication. This would require a scale-up in power from the small 200–400 watt transmitters Marconi had used up to then. He contracted Fleming, an expert in power engineering, to design the radio transmitter. Fleming designed the world's first large
radio transmitter In electronics and telecommunications, a radio transmitter or just transmitter (often abbreviated as XMTR or TX in technical documents) is an electronic device which produces radio waves with an antenna with the purpose of signal transmissio ...
, a complicated spark transmitter powered by a 25 kW alternator driven by a combustion engine, built at Poldhu in
Cornwall Cornwall (; or ) is a Ceremonial counties of England, ceremonial county in South West England. It is also one of the Celtic nations and the homeland of the Cornish people. The county is bordered by the Atlantic Ocean to the north and west, ...
, UK, which transmitted the first radio transmission across the Atlantic on 12 December 1901. Although Fleming was responsible for the design, the director of the Marconi Co. had made Fleming agree that: "If we get across the Atlantic, the main credit will be and must forever be Mr. Marconi's". Accordingly, the worldwide acclaim that greeted this landmark accomplishment went to Marconi, who only credited Fleming along with several other Marconi employees, saying he did some work on the "power plant". Marconi also forgot a promise to give Fleming 500 shares of Marconi stock if the project was successful. Fleming was bitter about his treatment. He honoured his agreement and did not speak about it throughout Marconi's life, but after his death in 1937 said Marconi had been "very ungenerous". In 1904, working for the Marconi company to improve transatlantic radio reception, Fleming invented the first
thermionic Thermionic emission is the liberation of charged particles from a hot electrode whose thermal energy gives some particles enough kinetic energy to escape the material's surface. The particles, sometimes called ''thermions'' in early literature, a ...
vacuum tube A vacuum tube, electron tube, thermionic valve (British usage), or tube (North America) is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. It ...
, the two-electrode
diode A diode is a two-Terminal (electronics), terminal electronic component that conducts electric current primarily in One-way traffic, one direction (asymmetric electrical conductance, conductance). It has low (ideally zero) Electrical resistance ...
, which he called the oscillation valve, for which he received a patent on 16 November. It became known as the
Fleming valve The Fleming valve, also called the Fleming oscillation valve, was a thermionic valve or vacuum tube invented in 1904 by English physicist John Ambrose Fleming as a detector for early radio receivers used in electromagnetic wireless telegrap ...
. The
Supreme Court of the United States The Supreme Court of the United States (SCOTUS) is the highest court in the federal judiciary of the United States. It has ultimate appellate jurisdiction over all Federal tribunals in the United States, U.S. federal court cases, and over Stat ...
later invalidated the patent because of an improper disclaimer and, additionally, maintained the technology in the patent was known art when filed. This invention of the
vacuum tube A vacuum tube, electron tube, thermionic valve (British usage), or tube (North America) is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. It ...
is often considered to have been the beginning of
electronics Electronics is a scientific and engineering discipline that studies and applies the principles of physics to design, create, and operate devices that manipulate electrons and other Electric charge, electrically charged particles. It is a subfield ...
. Fleming's diode was used in radio receivers and
radars Radar is a system that uses radio waves to determine the distance ('' ranging''), direction (azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track aircr ...
for many decades afterwards, until it was superseded by solid state electronic technology more than 50 years later. In 1906,
Lee De Forest #REDIRECT Lee de Forest {{redirect category shell, {{R from move{{R from other capitalisation ...
of the US added a control "grid" to the valve to create an amplifying
vacuum tube A vacuum tube, electron tube, thermionic valve (British usage), or tube (North America) is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. It ...
RF detector called the ''
Audion The Audion was an electronic detecting or amplifying vacuum tube invented by American electrical engineer Lee de Forest as a diode in 1906.De Forest patented a number of variations of his detector tubes starting in 1906. The patent that most cle ...
'', leading Fleming to accuse him of infringing his patents. De Forest's tube developed into the
triode A triode is an electronic amplifier, amplifying vacuum tube (or ''thermionic valve'' in British English) consisting of three electrodes inside an evacuated glass envelope: a heated Electrical filament, filament or cathode, a control grid, grid ...
the first electronic
amplifier An amplifier, electronic amplifier or (informally) amp is an electronic device that can increase the magnitude of a signal (a time-varying voltage or current). It is a two-port electronic circuit that uses electric power from a power su ...
. The triode was vital in the creation of long-distance telephone and radio communications, radars, and early electronic digital computers (mechanical and electro-mechanical digital computers already existed using different technology). The court battle over these patents lasted for many years with victories at different stages for both sides. Fleming also contributed in the fields of
photometry Photometry can refer to: * Photometry (optics), the science of measurement of visible light in terms of its perceived brightness to human vision * Photometry (astronomy), the measurement of the flux or intensity of an astronomical object's electr ...
,
electronics Electronics is a scientific and engineering discipline that studies and applies the principles of physics to design, create, and operate devices that manipulate electrons and other Electric charge, electrically charged particles. It is a subfield ...
,
wireless telegraphy Wireless telegraphy or radiotelegraphy is the transmission of text messages by radio waves, analogous to electrical telegraphy using electrical cable, cables. Before about 1910, the term ''wireless telegraphy'' was also used for other experimenta ...
(radio), and electrical measurements. He coined the term ''
power factor In electrical engineering, the power factor of an AC power system is defined as the ratio of the ''real power'' absorbed by the electrical load, load to the ''apparent power'' flowing in the circuit. Real power is the average of the instantaneou ...
'' to describe the true power flowing in an
AC power In an electric circuit, instantaneous power is the time rate of flow of energy past a given point of the circuit. In alternating current circuits, energy storage elements such as inductors and capacitors may result in periodic reversals of the d ...
system. Fleming retired from University College London in 1927 at the age of 77. He remained active, becoming a committed advocate of the new technology of Television which included serving as the second president of the Television Society. He was knighted in 1929, and died at his home in
Sidmouth Sidmouth () is a town on the English Channel in Devon, South West England, southeast of Exeter. With a population of 13,258 in 2021, it is a tourist resort and a gateway to the Jurassic Coast World Heritage Site. A large part of the town has ...
, Devon in 1945. His contributions to electronic communications and
radar Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track ...
were of vital importance in winning
World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
. Fleming was awarded the
IRE Medal of Honor The IEEE Medal of Honor is the highest recognition of the American Institute of Electrical and Electronics Engineers (IEEE). It has been awarded since 1917, and is presented to an individual or team of up to three who have made exceptional contri ...
in 1933 for "the conspicuous part he played in introducing physical and engineering principles into the radio art". In 1941 the London Power Company commemorated Fleming by naming a new 1,555 GRT coastal collier SS ''Ambrose Fleming''. On 27 November 2004 a
Blue Plaque A blue plaque is a permanent sign installed in a public place in the United Kingdom, and certain other countries and territories, to commemorate a link between that location and a famous person, event, or former building on the site, serving a ...
presented by the
Institute of Physics The Institute of Physics (IOP) is a UK-based not-for-profit learned society and professional body that works to advance physics education, physics research, research and applied physics, application. It was founded in 1874 and has a worldwide ...
was unveiled at the Norman Lockyer Observatory,
Sidmouth Sidmouth () is a town on the English Channel in Devon, South West England, southeast of Exeter. With a population of 13,258 in 2021, it is a tourist resort and a gateway to the Jurassic Coast World Heritage Site. A large part of the town has ...
, to mark 100 years since the invention of the thermionic radio valve.


Creationism

Fleming was a Christian creationist who argued against evolution. He was President of the Victoria Institute from 1927 to 1942.


Collections

In 1945 Fleming's widow donated Fleming's library and papers to
University College London University College London (Trade name, branded as UCL) is a Public university, public research university in London, England. It is a Member institutions of the University of London, member institution of the Federal university, federal Uni ...
. Fleming's library, which totals around 950 items, includes first editions of works by prominent scientists and engineers such as
James Clerk Maxwell James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish physicist and mathematician who was responsible for the classical theory of electromagnetic radiation, which was the first theory to describe electricity, magnetism an ...
,
Oliver Lodge Sir Oliver Joseph Lodge (12 June 1851 – 22 August 1940) was an English physicist whose investigations into electromagnetic radiation contributed to the development of Radio, radio communication. He identified electromagnetic radiation indepe ...
, James Dewar and Shelford Bidwell. Fleming's archive spans 521 volumes and 12 boxes; it contains his laboratory notebooks, lecture notes, patent specifications, and correspondence.


Books by Fleming

*''Electric Lamps and Electric Lighting: A course of four lectures on electric illumination delivered at the Royal Institution of Great Britain'' (1894) 228 pages, . *''The Alternate Current Transformer in Theory and Practice'' "The Electrician" Printing and Publishing Company (1896) *''Magnets and Electric Currents'' E. & F. N. Spon. (1898) *''A Handbook for the Electrical Laboratory and Testing Room'' "The Electrician" Printing and Publishing Company (1901) *''Waves and Ripples in Water, Air, and Aether'' MacMillan (1902). *''The Evidence of Things Not Seen'' Christian Knowledge Society: London (1904) *''The Principles of Electric Wave Telegraphy'' (1906), Longmans Green, London, 671 pages. *''The Propagation of Electric Currents in Telephone and Telegraph Conductors'' (1908) Constable, 316 pages. *''An Elementary Manual of Radiotelegraphy and Radiotelephony'' (1911) Longmans Green, London, 340 pages. *''On the power factor and conductivity of dielectrics when tested with alternating electric currents of telephonic frequency at various temperatures '' (1912) Gresham, 82 pages, ASIN: B0008CJBIC *''The Wonders of Wireless Telegraphy : Explained in simple terms for the non-technical reader'' Society for promoting Christian Knowledge (1913) *''The Wireless Telegraphist's Pocket Book of Notes, Formulae and Calculations'' The Wireless Press (1915) *''The Thermionic Valve and its Development in Radio Telegraphy and Telephony'' (1919). *''Fifty Years of Electricity'' The Wireless Press (1921) *''Electrons, Electric Waves and Wireless telephony'' The Wireless Press (1923) *''Introduction to Wireless Telegraphy and Telephony'' Sir Isaac Pitman and Sons Ltd. (1924) *''Mercury-arc Rectifiers and Mercury-vapour Lamps'' London. Pitman (1925) *''The Electrical Educator'' (3 volumes), The New Era Publishing Co Ltd (1927) *''Television'' Television Press London. (1928) *''Memories of a Scientific life'' Marshall, Morgan & Scott (1934) *''Evolution or Creation?'' (1938) Marshall Morgan and Scott, 114 pages, ASIN: B00089BL7Y – outlines objections to Darwin. *''Mathematics for Engineers'' George Newnes Ltd (1938) *''Physics for Engineers'' George Newnes Ltd (1941)


References


External links

* * * *
IEEE History Center biographyDepartment of Electronic & Electrical Engineering, UCL – home of the original Fleming valve100 Years of Electronics 2004 – The Centenary of the Fleming ValveLife and Times of Ambrose FlemingFleming Book Collection
at
University College London University College London (Trade name, branded as UCL) is a Public university, public research university in London, England. It is a Member institutions of the University of London, member institution of the Federal university, federal Uni ...

Fleming Papers
at
University College London University College London (Trade name, branded as UCL) is a Public university, public research university in London, England. It is a Member institutions of the University of London, member institution of the Federal university, federal Uni ...
{{DEFAULTSORT:Fleming, John Ambrose 1849 births 1945 deaths British Christian creationists People from Lancaster, Lancashire People from Maida Vale English physicists English electrical engineers English inventors English knights Academics of University College London Academics of the University of Nottingham Alumni of University College London Alumni of St John's College, Cambridge IEEE Medal of Honor recipients European amateur radio operators Fellows of the Royal Society People educated at University College School Presidents of the Royal Television Society History of radio in the United Kingdom Alumni of the Royal College of Science Knights Bachelor People educated at Lancaster Royal Grammar School Recipients of Franklin Medal