- John Ambrose Fleming
name = Sir J. Ambrose Fleming
birth_name = John Ambrose Fleming
birth_date = birth date|1849|11|29|mf=y
birth_place = Lancaster,
death_date = death date and age|1945|4|18|1849|11|29|mf=y
Sidmouth, Devon, England
residence = England
nationality = English
Electrical engineerand physicist
University College, London University of Nottingham Cambridge UniversityEdison Electric Light Co.
University College, LondonRoyal College of Science
Balthasar van der Pol
Fleming's left hand rule Fleming's right hand rule Kenotron
Hughes Medal(1910)IRE Medal of Honor (1933)
religion = Congregationalist
Sir John Ambrose Fleming (
November 29, 1849- April 18, 1945) was an English electrical engineerand physicist. He is known for inventing the first thermionic valveor vacuum tube, the diode, then called the kenotronin 1904. [cite web|last=Harr|first=Chris|title=Ambrose J. Fleming biography|date=2003-06-23|work=Pioneers of Computing|publisher=The History of Computing Project|url=http://www.thocp.net/biographies/fleming_ambrose.htm|accessdate=2008-04-30] He also invented the right hand rule, used in mathematicsand electronics. [cite web|title=Right and left hand rules|work=Tutorials, Magnet Lab U.|publisher=National High Magnetic Field Laboratory|url=http://www.magnet.fsu.edu/education/tutorials/java/handrules/index.html|accessdate=2008-04-30] He was born the eldest of seven children of James Fleming DD (d. 1879), a Congregational minister, and his wife, Mary Ann, at Lancaster, Lancashireand baptised on February 11 1850. He was a devout Christian and preached on one occasion at St Martin-in-the-Fieldsin London on the topic of evidence for the resurrection. In 1932, along with Douglas Dewarand Bernard Acworth, he helped establish the Evolution Protest Movement. Having no children, he bequeathed much of his estate to Christian charities, especially those that helped the poor. He was an accomplished photographer and, in addition, he painted watercolours and enjoyed climbing in the Alps.
Ambrose Fleming was born in Lancaster and educated at
University College School, London, and University College London. He won a fellowship to St John's College, Cambridgein 1877, and went on to Lecture at several universities including the University of Cambridge, the University of Nottingham, and University College London, where he was the first professorof Electrical Engineering. He was also consultant to the Marconi Wireless Telegraph Company, Swan Company, Ferranti, Edison Telephone, and later the Edison Electric Light Company. In 1892, Fleming presented an important paper on electrical transformertheory to the Institution of Electrical Engineersin London.
Education and marriages
Fleming started school at about the age of ten, attending a private school where he particularly enjoyed
geometry. 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 Schoolwhere, although accomplished at maths, he habitually came bottom of the class at Latin.
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.
He enrolled for a BSc degree at
University College, London, graduated in 1870, and studied under the mathematician Augustus de Morganand the physicist George Carey Foster. He became a student of chemistry at the Royal College of Sciencein South Kensingtonin London (now Imperial College). There he first studied Alessandro Volta'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) 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 2890 he became science master at Cheltenham College, a public school, earning £400 per year. (He later also taught at Rossall School.) His own scientific research continued and he corresponded with James Clerk Maxwellat Cambridge University. 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. 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 Honoursdegree in chemistry and physics. He then obtained a DSc from London and served one year at Cambridge Universityas a demonstrator of mechanical engineering before being appointed as the first Professorof Physicsand Mathematicsat the University of Nottingham, but he left after less than a year.
11 June 1887he married Clara Ripley (1856/7–1917), daughter of Walter Freake Pratt, a solicitor from Bath. On 27 July 1928he married the popular young singer Olive May Franks(b. 1898/9), of Bristol, daughter of George Franks, a Cardiffbusinessman.
Activities and achievements
In November 1904, he invented and patented the two-electrode vacuum-tube rectifier, which he called the oscillation valve. It was also called a
thermionic valve, vacuum diode, kenotron, thermionic tube, or Fleming valve. The Supreme Court of the United Stateslater invalidated the patent because of an improper disclaimer and, additionally, maintained the technology in the patent was known art when filed. [ [http://www.mercurians.org/nov98/misreading.html "Misreading the Supreme Court: A Puzzling Chapter in the History of Radio"] . November 1998, Mercurians.org.] This invention is often considered to have been the beginning of electronics, for this was the first vacuum tube.Fact|date=May 2007 Fleming's diodewas used in radioreceivers and radarsfor many decades afterwards, until it was superseded by solid stateelectronic technology more than 50 years later.
Lee De Forestof the U.S. added a control "grid" to the valve to create a vacuum tubeRF detector called the "Audion", leading Fleming to accuse him of copying his ideas. De Forest's device was shortly refined by him and Edwin H. Armstronginto the first electronic amplifier, a tube called the triode. 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). Fleming also contributed in the fields of photometry, electronics, wireless telegraphy(radio), and electrical measurements. He was knighted in 1929, and died at his home in Sidmouth, Devonin 1945. His contributions to electronic communications and radarwere of vital importance in winning World War II. Fleming was awarded the IRE Medal of Honor in 1933 for "the conspicuous part he played in introducing physical and engineering principles into the radio art".
Note from eulogy at the
Centenarycelebration of the invention of the thermionic valve:
:One century ago, in November 1904, John Ambrose Fleming FRS,
Pender Professorat UCL, filed patent|GB|190424850| in Great Britain, for a device called the Thermionic Valve. When inserted together with a galvanometer, into a tuned electrical circuit, it could be used as a very sensitive rectifying detector of high frequencywireless currents, known as radio waves. It was a major step forward in the ‘wireless revolution’.
In November 1905, he patented the "Fleming Valve" (patent|US|803684|). As a rectifying diode, and forerunner to the
triodevalve and many related structures, it can also be considered to be the device that gave birth to modern electronics.
In the ensuing years such valves, were largely superseded by "
cat’s whiskers", and decades later most electron tubes, as they became generically known, were gradually replaced by semiconductordiodes and transistors, which were significantly smaller, cheaper, and more reliable. In time and in turn, even these have been largely replaced by integrated circuits, better known as silicon chips.
Today, descendants of the original vacuum tube still play an important role in a range of applications. They can be found in the power stages of radio and television transmitters, in audio amplifiers, as detectors of optical and
short wavelength radiation, and in sensitive equipment that must be "radiation-hard".
On the 27th November 2004 a
Blue Plaque(presented by the Institute of Physics) was unveiled at the " Norman Lockyer Observatory", Sidmouth, to mark 100 years since the invention of the Thermionic Radio Valve.
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, ISBN 0548479377.
* "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)
* "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)
* [http://www.ieee.org/web/aboutus/history_center/biography/fleming.html IEEE History Center biography]
* [http://www.ee.ucl.ac.uk Department of Electronic & Electrical Engineering, UCL - home of the original Fleming valve]
* [http://www.ee.ucl.ac.uk/Fleming 100 Years of Electronics 2004 - The Centenary of the Fleming Valve]
NAME= Fleming, Sir J. Ambrose
Electrical engineerand physicist
DATE OF BIRTH= birth date|1849|11|29|mf=y
PLACE OF BIRTH= Lancaster,
DATE OF DEATH= death date|1945|4|18|mf=y
PLACE OF DEATH=
Sidmouth, Devon, England
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John Ambrose Fleming — Sir John Ambrose Fleming (* 29. November 1849 in Lancaster, Lancashire; † 18. April 1945 in Sidmouth, Devon), manchmal auch Ambrose J. Fleming genannt, war ein britischer Elektroingenieur und Physiker. Seine Eltern waren James und Mary Anne… … Deutsch Wikipedia
John Ambrose Fleming — Pour les articles homonymes, voir Fleming. Scientifique britannique et inventeur de la diode, Sir John Ambrose Fleming, parfois également appelé Ambrose John Fleming, est né à Lancaster le 29 novembre 1849 et à vécu jusqu’en avril 1945 … Wikipédia en Français
John Ambrose Fleming — Sir John Ambrose Fleming (Lancaster, 29 de noviembre de 1848 Devon, 18 de abril de 1945), físico e ingeniero eléctrico británico. Estudió en el University College School y más tarde en el University College London. En noviembre de 1904 inventó el … Wikipedia Español
John Ambrose Fleming — Sir John Ambrose Fleming (Lancaster, 29 de noviembre de 1848 Devon, 18 de abril de 1945), físico e ingeniero eléctrico británico). Estudió en el University College School y más tarde en el University College London. En noviembre de 1904 inventó… … Enciclopedia Universal
Fleming , Sir John Ambrose — (1849–1945) British physicist and electrical engineer Fleming, who was born at Lancaster, studied for a short time at University College, London, but left before graduating. However, he continued his work for a science degree in his leisure hours … Scientists
Fleming, Sir John Ambrose — ▪ British engineer born Nov. 29, 1849, Lancaster, Lancashire, Eng. died April 18, 1945, Sidmouth, Devon English engineer who made numerous contributions to electronics, photometry, electric measurements, and wireless telegraphy. After … Universalium
Ambrose John Fleming — John Ambrose Fleming Pour les articles homonymes, voir Fleming. Scientifique britannique et inventeur de la diode, Sir John Ambrose Fleming, parfois également appelé Ambrose John Fleming, est né à Lancaster le 29 novembre 1848 et à vécu … Wikipédia en Français
Fleming valve — schematic from US Patent 803,684. The Fleming valve, also called the Fleming oscillation valve, was a vacuum tube diode invented by John Ambrose Fleming and used in the earliest days of radio communication. As the first vacuum tube, the IEEE has… … Wikipedia
John Fleming (disambiguation) — John Fleming may refer to: * John Fleming (18th century), judge in Cumberland County, Virginia * John Ambrose Fleming (born 1849), inventor of the Fleming Valve * John Fleming (Canadian politician) (1819 1877), Canadian politician * John Fleming… … Wikipedia
Fleming (Familienname) — Fleming ist ein Familienname. Bekannte Namensträger Inhaltsverzeichnis A B C D E F G H I J K L M N O P Q R S T U V W X Y Z … Deutsch Wikipedia