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101 Ader, Clément
SUBJECT AREA: Aerospace[br]b. 2 April 1841 Muret, Franced. 3 May 1925 Toulouse, France[br]French engineer who made a short "hop" in a powered aeroplane in 1890.[br]Ader was a distinguished engineer and versatile inventor who was involved with electrical developments, including the telephone and air-cushion vehicles. In the field of aeronautics he became the centre of a long-lasting controversy: did he, or did he not, fly before the Wright brothers' flight of 1903? In 1882 Ader started work on his first aeroplane, the Eole (god of the winds), which was bat-like in appearance and powered by a very well-designed lightweight steam engine developing about 15 kW (20 hp). On 9 October 1890 the Eole was ready, and with Ader as pilot it increased speed over a level surface and lifted off the ground. It was airborne for about 5 seconds and covered some 50 m (164 ft), reaching a height of 20 cm (8 in.). Whether such a short hop constituted a flight has caused much discussion and argument over the years. An even greater controversy followed Ader's claim in 1906 that his third aeroplane (Avion III) had made a flight of 300 m (328 yd) in 1897. He repeated this claim in his book written in 1907, and many historians accepted his account of the "flight". C.H.Gibbs-Smith, an eminent aviation historian, investigated the Ader controversy and in his book published in 1966 came to the conclusion that the Avion III did not fly at all. Avion III was donated to the Museum of the Conservatoire des Arts et Métiers in Paris, and still survives. From 1906 onwards Ader concentrated his inventive efforts elsewhere, but he did mount a successful campaign to persuade the French War Ministry to create an air force.[br]Principal Honours and DistinctionsIn 1990 the French Government accepted him as the "Father of Aviation who gave wings to the world".Bibliography1890, patent no. 205, 155 (included a description of the Eole).1907, La Première étape de l'aviation militaire en France, Paris (the most significant of his published books and articles).Further ReadingC.H.Gibbs-Smith, 1968, Clément Ader: His Flight Claims and His Place in History, London.The centenary of Ader's 1890 flight resulted in several French publications, including: C.Carlier, 1990, L'Affaire Clément Ader: la vérité rétablie, Paris; Pierre Lissarrague, 1990, Clément Ader: inventeur d'avions, Toulouse.JDS -
102 Agricola, Georgius (Georg Bauer)
SUBJECT AREA: Metallurgy[br]b. 24 March 1494 Glauchau, Saxonyd. 21 November 1555 Chemnitz, Germany[br]German metallurgist, who wrote the book De Re Metallica under the latinized version of his name.[br]Agricola was a physician, scientist and metallurgist of note and it was this which led to the publication of De Re Metallica. He studied at Leipzig University and between 1518 and 1522 he was a school teacher in Zwickau. Eventually he settled as a physician in Chemnitz. Later he continued his medical practice at Joachimstal in the Erzgebirge. This town was newly built to serve the mining community in what was at the time the most important ore-mining field in both Germany and Europe.As a physician in the sixteenth century he would naturally have been concerned with the development of medicines, which would have led him to research the medical properties of ores and base metals. He studied the mineralogy of his area, and the mines, and the miners who were working there. He wrote several books in Latin on geology and mineralogy. His important work during that period was a glossary of mineralogical and mining terms in both Latin and German. It is, however, De Re Metallica for which he is best known. This large volume contains twelve books which deal with mining and metallurgy, including an account of glassmaking. Whilst one can understand the text of this book very easily, the quality of the illustrative woodcuts should not be neglected. These illustrations detail the mines, furnaces, forges and the plant associated with them, unfortunately the name of the artist is unknown. The importance of the work lies in the fact that it is an assemblage of information on all the methods and practices current at that time. The book was clearly intended as a textbook of mining and mineralogy and as such it would have been brought to England by German engineers when they were employed by the Mines Royal in the Keswick area in the late sixteenth century. In addition to his studies in preparation for De Re Metallica, Agricola was an "adventurer" holding shares in the Gottesgab mine in the Erzegebirge.[br]Principal Honours and Distinctions Bibliography1556, De Re Metallica, Basel; 1912, trans. H. Hoover and L.H.Hoover, London.KMBiographical history of technology > Agricola, Georgius (Georg Bauer)
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103 Alden, George I.
SUBJECT AREA: Mechanical, pneumatic and hydraulic engineering[br]b. 22 April 1843 Templeton, Massachusetts, USAd. 13 September 1926 Princeton, Massachusetts, USA[br]American mechanical engineer and professor of engineering.[br]From 1868 to 1896 George Alden was head of the steam and mechanical engineering departments at the Worcester Polytechnic Institute, Worcester, Massachusetts. He made a donation in 1910 to establish a hydraulic laboratory at the Institute, and later a further donation for an extension of the laboratory which was completed in 1925. He was Chairman of the Board of Norton (Abrasives) Company and made a significant contribution to the theory of grinding in his paper in 1914 to the American Society of Mechanical Engineers. He was a member of that society from 1880, the year of its foundation, and took an active part in its proceedings.[br]Principal Honours and DistinctionsVice-President, American Society of Mechanical Engineers 1891–3.Bibliography1914, "Operation of grinding wheels in machine grinding", Transactions of the American Society of Mechanical Engineers 36:451–60.Further ReadingFor a description of the Alden Hydraulic Laboratory, see Mechanical Engineering, June 1926: 634–5.RTS -
104 Alexanderson, Ernst Frederik Werner
[br]b. 25 January 1878 Uppsala, Swedend. ? May 1975 Schenectady, New York, USA[br]Swedish-American electrical engineer and prolific radio and television inventor responsible for developing a high-frequency alternator for generating radio waves.[br]After education in Sweden at the High School and University of Lund and the Royal Institution of Technology in Stockholm, Alexanderson took a postgraduate course at the Berlin-Charlottenburg Engineering College. In 1901 he began work for the Swedish C \& C Electric Company, joining the General Electric Company, Schenectady, New York, the following year. There, in 1906, together with Fessenden, he developed a series of high-power, high-frequency alternators, which had a dramatic effect on radio communications and resulted in the first real radio broadcast. His early interest in television led to working demonstrations in his own home in 1925 and at the General Electric laboratories in 1927, and to the first public demonstration of large-screen (7 ft (2.13 m) diagonal) projection TV in 1930. Another invention of significance was the "amplidyne", a sensitive manufacturing-control system subsequently used during the Second World War for controlling anti-aircraft guns. He also contributed to developments in electric propulsion and radio aerials.He retired from General Electric in 1948, but continued television research as a consultant for the Radio Corporation of America (RCA), filing his 321st patent in 1955.[br]Principal Honours and DistinctionsInstitution of Radio Engineers Medal of Honour 1919. President, IERE 1921. Edison Medal 1944.BibliographyPublications relating to his work in the early days of radio include: "Magnetic properties of iron at frequencies up to 200,000 cycles", Transactions of the American Institute of Electrical Engineers (1911) 30: 2,443."Transatlantic radio communication", Transactions of the American Institute of ElectricalEngineers (1919) 38:1,269.The amplidyne is described in E.Alexanderson, M.Edwards and K.Boura, 1940, "Dynamo-electric amplifier for power control", Transactions of the AmericanInstitution of Electrical Engineers 59:937.Further ReadingE.Hawkes, 1927, Pioneers of Wireless, Methuen (provides an account of Alexanderson's work on radio).J.H.Udelson, 1982, The Great Television Race: A History of the American Television Industry 1925–1941, University of Alabama Press (provides further details of his contribution to the development of television).KFBiographical history of technology > Alexanderson, Ernst Frederik Werner
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105 Allen, Horatio
[br]b. 10 May 1802 Schenectady, New York, USAd. 1 January 1890 South Orange, New Jersey, USA[br]American engineer, pioneer of steam locomotives.[br]Allen was the Resident Engineer for construction of the Delaware \& Hudson Canal and in 1828 was instructed by J.B. Jervis to visit England to purchase locomotives for the canal's rail extension. He drove the locomotive Stourbridge Lion, built by J.U. Rastrick, on its first trial on 9 August 1829, but weak track prevented its regular use.Allen was present at the Rainhill Trials on the Liverpool \& Manchester Railway in October 1829. So was E.L.Miller, one of the promoters of the South Carolina Canal \& Rail Road Company, to which Allen was appointed Chief Engineer that autumn. Allen was influential in introducing locomotives to this railway, and the West Point Foundry built a locomotive for it to his design; it was the first locomotive built in the USA for sale. This locomotive, which bore some resemblance to Novelty, built for Rainhill by John Braithwaite and John Ericsson, was named Best Friend of Charleston. On Christmas Day 1830 it hauled the first scheduled steam train to run in America, carrying 141 passengers.In 1832 the West Point Foundry built four double-ended, articulated 2–2–0+0–2–2 locomotives to Horatio Allen's design for the South Carolina railroad. From each end of a central firebox extended two boiler barrels side by side with common smokeboxes and chimneys; wheels were mounted on swivelling sub-frames, one at each end, beneath these boilers. Allen's principal object was to produce a powerful locomotive with a light axle loading.Allen subsequently became a partner in Stillman, Allen \& Co. of New York, builders of marine engines, and in 1843 was President of the Erie Railroad.[br]Further ReadingJ.Marshall, 1978, A Biographical Dictionary of Railway Engineers, Newton Abbot: David \& Charles.Dictionary of American Biography.R.E.Carlson, 1969, The Liverpool \& Manchester Railway Project 1821–1831, Newton Abbot: David \& Charles.J.F.Stover, 1961, American Railroads, Chicago: University of Chicago Press.J.H.White Jr, 1994, "Old debts and new visions", in Common Roots—Separate Branches, London: Science Museum, 79–82.PJGR -
106 Appleton, Sir Edward Victor
[br]b. 6 September 1892 Bradford, Englandd. 21 April 1965 Edinburgh, Scotland[br]English physicist awarded the Nobel Prize for Physics for his discovery of the ionospheric layer, named after him, which is an efficient reflector of short radio waves, thereby making possible long-distance radio communication.[br]After early ambitions to become a professional cricketer, Appleton went to St John's College, Cambridge, where he studied under J.J.Thompson and Ernest Rutherford. His academic career interrupted by the First World War, he served as a captain in the Royal Engineers, carrying out investigations into the propagation and fading of radio signals. After the war he joined the Cavendish Laboratory, Cambridge, as a demonstrator in 1920, and in 1924 he moved to King's College, London, as Wheatstone Professor of Physics.In the following decade he contributed to developments in valve oscillators (in particular, the "squegging" oscillator, which formed the basis of the first hard-valve time-base) and gained international recognition for research into electromagnetic-wave propagation. His most important contribution was to confirm the existence of a conducting ionospheric layer in the upper atmosphere capable of reflecting radio waves, which had been predicted almost simultaneously by Heaviside and Kennelly in 1902. This he did by persuading the BBC in 1924 to vary the frequency of their Bournemouth transmitter, and he then measured the signal received at Cambridge. By comparing the direct and reflected rays and the daily variation he was able to deduce that the Kennelly- Heaviside (the so-called E-layer) was at a height of about 60 miles (97 km) above the earth and that there was a further layer (the Appleton or F-layer) at about 150 miles (240 km), the latter being an efficient reflector of the shorter radio waves that penetrated the lower layers. During the period 1927–32 and aided by Hartree, he established a magneto-ionic theory to explain the existence of the ionosphere. He was instrumental in obtaining agreement for international co-operation for ionospheric and other measurements in the form of the Second Polar Year (1932–3) and, much later, the International Geophysical Year (1957–8). For all this work, which made it possible to forecast the optimum frequencies for long-distance short-wave communication as a function of the location of transmitter and receiver and of the time of day and year, in 1947 he was awarded the Nobel Prize for Physics.He returned to Cambridge as Jacksonian Professor of Natural Philosophy in 1939, and with M.F. Barnett he investigated the possible use of radio waves for radio-location of aircraft. In 1939 he became Secretary of the Government Department of Scientific and Industrial Research, a post he held for ten years. During the Second World War he contributed to the development of both radar and the atomic bomb, and subsequently served on government committees concerned with the use of atomic energy (which led to the establishment of Harwell) and with scientific staff.[br]Principal Honours and DistinctionsKnighted (KCB 1941, GBE 1946). Nobel Prize for Physics 1947. FRS 1927. Vice- President, American Institute of Electrical Engineers 1932. Royal Society Hughes Medal 1933. Institute of Electrical Engineers Faraday Medal 1946. Vice-Chancellor, Edinburgh University 1947. Institution of Civil Engineers Ewing Medal 1949. Royal Medallist 1950. Institute of Electrical and Electronics Engineers Medal of Honour 1962. President, British Association 1953. President, Radio Industry Council 1955–7. Légion d'honneur. LLD University of St Andrews 1947.Bibliography1925, joint paper with Barnett, Nature 115:333 (reports Appleton's studies of the ionosphere).1928, "Some notes of wireless methods of investigating the electrical structure of the upper atmosphere", Proceedings of the Physical Society 41(Part III):43. 1932, Thermionic Vacuum Tubes and Their Applications (his work on valves).1947, "The investigation and forecasting of ionospheric conditions", Journal of theInstitution of Electrical Engineers 94, Part IIIA: 186 (a review of British work on the exploration of the ionosphere).with J.F.Herd \& R.A.Watson-Watt, British patent no. 235,254 (squegging oscillator).Further ReadingWho Was Who, 1961–70 1972, VI, London: A. \& C.Black (for fuller details of honours). R.Clark, 1971, Sir Edward Appleton, Pergamon (biography).J.Jewkes, D.Sawers \& R.Stillerman, 1958, The Sources of Invention.KFBiographical history of technology > Appleton, Sir Edward Victor
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107 Arkwright, Sir Richard
SUBJECT AREA: Textiles[br]b. 23 December 1732 Preston, Englandd. 3 August 1792 Cromford, England[br]English inventor of a machine for spinning cotton.[br]Arkwright was the youngest of thirteen children and was apprenticed to a barber; when he was about 18, he followed this trade in Bol ton. In 1755 he married Patients Holt, who bore him a son before she died, and he remarried in 1761, to Margaret Biggins. He prospered until he took a public house as well as his barber shop and began to lose money. After this failure, he travelled around buying women's hair for wigs.In the late 1760s he began spinning experiments at Preston. It is not clear how much Arkwright copied earlier inventions or was helped by Thomas Highs and John Kay but in 1768 he left Preston for Nottingham, where, with John Smalley and David Thornley as partners, he took out his first patent. They set up a mill worked by a horse where machine-spun yarn was produced successfully. The essential part of this process lay in drawing out the cotton by rollers before it was twisted by a flyer and wound onto the bobbin. The partners' resources were not sufficient for developing their patent so Arkwright found new partners in Samuel Need and Jedediah Strutt, hosiers of Nottingham and Derby. Much experiment was necessary before they produced satisfactory yarn, and in 1771 a water-driven mill was built at Cromford, where the spinning process was perfected (hence the name "waterframe" was given to his spinning machine); some of this first yarn was used in the hosiery trade. Sales of all-cotton cloth were initially limited because of the high tax on calicoes, but the tax was lowered in 1774 by Act of Parliament, marking the beginning of the phenomenal growth of the cotton industry. In the evidence for this Act, Arkwright claimed that he had spent £12,000 on his machine. Once Arkwright had solved the problem of mechanical spinning, a bottleneck in the preliminary stages would have formed but for another patent taken out in 1775. This covered all preparatory processing, including some ideas not invented by Arkwright, with the result that it was disputed in 1783 and finally annulled in 1785. It contained the "crank and comb" for removing the cotton web off carding engines which was developed at Cromford and solved the difficulty in carding. By this patent, Arkwright had mechanized all the preparatory and spinning processes, and he began to establish water-powered cotton mills even as far away as Scotland. His success encouraged many others to copy him, so he had great difficulty in enforcing his patent Need died in 1781 and the partnership with Strutt ended soon after. Arkwright became very rich and financed other spinning ventures beyond his immediate control, such as that with Samuel Oldknow. It was estimated that 30,000 people were employed in 1785 in establishments using Arkwright's patents. In 1786 he received a knighthood for delivering an address of thanks when an attempt to assassinate George III failed, and the following year he became High Sheriff of Derbyshire. He purchased the manor of Cromford, where he died in 1792.[br]Principal Honours and DistinctionsKnighted 1786.Bibliography1769, British patent no. 931.1775, British patent no. 1,111.Further ReadingR.S.Fitton, 1989, The Arkwrights, Spinners of Fortune, Manchester (a thorough scholarly work which is likely to remain unchallenged for many years).R.L.Hills, 1973, Richard Arkwright and Cotton Spinning, London (written for use in schools and concentrates on Arkwright's technical achievements).R.S.Fitton and A.P.Wadsworth, 1958, The Strutts and the Arkwrights, Manchester (concentrates on the work of Arkwright and Strutt).A.P.Wadsworth and J.de L.Mann, 1931, The Cotton Trade and Industrial Lancashire, Manchester (covers the period leading up to the Industrial Revolution).F.Nasmith, 1932, "Richard Arkwright", Transactions of the Newcomen Society 13 (looks at the actual spinning invention).R.L.Hills, 1970, Power in the Industrial Revolution, Manchester (discusses the technical problems of Arkwright's invention).RLH -
108 Armstrong, Edwin Howard
[br]b. 18 December 1890 New York City, New York, USAd. 31 January 1954 New York City, New York, USA[br]American engineer who invented the regenerative and superheterodyne amplifiers and frequency modulation, all major contributions to radio communication and broadcasting.[br]Interested from childhood in anything mechanical, as a teenager Armstrong constructed a variety of wireless equipment in the attic of his parents' home, including spark-gap transmitters and receivers with iron-filing "coherer" detectors capable of producing weak Morse-code signals. In 1912, while still a student of engineering at Columbia University, he applied positive, i.e. regenerative, feedback to a Lee De Forest triode amplifier to just below the point of oscillation and obtained a gain of some 1,000 times, giving a receiver sensitivity very much greater than hitherto possible. Furthermore, by allowing the circuit to go into full oscillation he found he could generate stable continuous-waves, making possible the first reliable CW radio transmitter. Sadly, his claim to priority with this invention, for which he filed US patents in 1913, the year he graduated from Columbia, led to many years of litigation with De Forest, to whom the US Supreme Court finally, but unjustly, awarded the patent in 1934. The engineering world clearly did not agree with this decision, for the Institution of Radio Engineers did not revoke its previous award of a gold medal and he subsequently received the highest US scientific award, the Franklin Medal, for this discovery.During the First World War, after some time as an instructor at Columbia University, he joined the US Signal Corps laboratories in Paris, where in 1918 he invented the superheterodyne, a major contribution to radio-receiver design and for which he filed a patent in 1920. The principle of this circuit, which underlies virtually all modern radio, TV and radar reception, is that by using a local oscillator to convert, or "heterodyne", a wanted signal to a lower, fixed, "intermediate" frequency it is possible to obtain high amplification and selectivity without the need to "track" the tuning of numerous variable circuits.Returning to Columbia after the war and eventually becoming Professor of Electrical Engineering, he made a fortune from the sale of his patent rights and used part of his wealth to fund his own research into further problems in radio communication, particularly that of receiver noise. In 1933 he filed four patents covering the use of wide-band frequency modulation (FM) to achieve low-noise, high-fidelity sound broadcasting, but unable to interest RCA he eventually built a complete broadcast transmitter at his own expense in 1939 to prove the advantages of his system. Unfortunately, there followed another long battle to protect and exploit his patents, and exhausted and virtually ruined he took his own life in 1954, just as the use of FM became an established technique.[br]Principal Honours and DistinctionsInstitution of Radio Engineers Medal of Honour 1917. Franklin Medal 1937. IERE Edison Medal 1942. American Medal for Merit 1947.Bibliography1922, "Some recent developments in regenerative circuits", Proceedings of the Institute of Radio Engineers 10:244.1924, "The superheterodyne. Its origin, developments and some recent improvements", Proceedings of the Institute of Radio Engineers 12:549.1936, "A method of reducing disturbances in radio signalling by a system of frequency modulation", Proceedings of the Institute of Radio Engineers 24:689.Further ReadingL.Lessing, 1956, Man of High-Fidelity: Edwin Howard Armstrong, pbk 1969 (the only definitive biography).W.R.Maclaurin and R.J.Harman, 1949, Invention \& Innovation in the Radio Industry.J.R.Whitehead, 1950, Super-regenerative Receivers.A.N.Goldsmith, 1948, Frequency Modulation (for the background to the development of frequency modulation, in the form of a large collection of papers and an extensive bibliog raphy).KFBiographical history of technology > Armstrong, Edwin Howard
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109 Armstrong, Sir William George, Baron Armstrong of Cragside
[br]b. 26 November 1810 Shieldfield, Newcastle upon Tyne, Englandd. 27 December 1900 Cragside, Northumbria, England[br]English inventor, engineer and entrepreneur in hydraulic engineering, shipbuilding and the production of artillery.[br]The only son of a corn merchant, Alderman William Armstrong, he was educated at private schools in Newcastle and at Bishop Auckland Grammar School. He then became an articled clerk in the office of Armorer Donkin, a solicitor and a friend of his father. During a fishing trip he saw a water-wheel driven by an open stream to work a marble-cutting machine. He felt that its efficiency would be improved by introducing the water to the wheel in a pipe. He developed an interest in hydraulics and in electricity, and became a popular lecturer on these subjects. From 1838 he became friendly with Henry Watson of the High Bridge Works, Newcastle, and for six years he visited the Works almost daily, studying turret clocks, telescopes, papermaking machinery, surveying instruments and other equipment being produced. There he had built his first hydraulic machine, which generated 5 hp when run off the Newcastle town water-mains. He then designed and made a working model of a hydraulic crane, but it created little interest. In 1845, after he had served this rather unconventional apprenticeship at High Bridge Works, he was appointed Secretary of the newly formed Whittle Dene Water Company. The same year he proposed to the town council of Newcastle the conversion of one of the quayside cranes to his hydraulic operation which, if successful, should also be applied to a further four cranes. This was done by the Newcastle Cranage Company at High Bridge Works. In 1847 he gave up law and formed W.G.Armstrong \& Co. to manufacture hydraulic machinery in a works at Elswick. Orders for cranes, hoists, dock gates and bridges were obtained from mines; docks and railways.Early in the Crimean War, the War Office asked him to design and make submarine mines to blow up ships that were sunk by the Russians to block the entrance to Sevastopol harbour. The mines were never used, but this set him thinking about military affairs and brought him many useful contacts at the War Office. Learning that two eighteen-pounder British guns had silenced a whole Russian battery but were too heavy to move over rough ground, he carried out a thorough investigation and proposed light field guns with rifled barrels to fire elongated lead projectiles rather than cast-iron balls. He delivered his first gun in 1855; it was built of a steel core and wound-iron wire jacket. The barrel was multi-grooved and the gun weighed a quarter of a ton and could fire a 3 lb (1.4 kg) projectile. This was considered too light and was sent back to the factory to be rebored to take a 5 lb (2.3 kg) shot. The gun was a complete success and Armstrong was then asked to design and produce an equally successful eighteen-pounder. In 1859 he was appointed Engineer of Rifled Ordnance and was knighted. However, there was considerable opposition from the notably conservative officers of the Army who resented the intrusion of this civilian engineer in their affairs. In 1862, contracts with the Elswick Ordnance Company were terminated, and the Government rejected breech-loading and went back to muzzle-loading. Armstrong resigned and concentrated on foreign sales, which were successful worldwide.The search for a suitable proving ground for a 12-ton gun led to an interest in shipbuilding at Elswick from 1868. This necessitated the replacement of an earlier stone bridge with the hydraulically operated Tyne Swing Bridge, which weighed some 1450 tons and allowed a clear passage for shipping. Hydraulic equipment on warships became more complex and increasing quantities of it were made at the Elswick works, which also flourished with the reintroduction of the breech-loader in 1878. In 1884 an open-hearth acid steelworks was added to the Elswick facilities. In 1897 the firm merged with Sir Joseph Whitworth \& Co. to become Sir W.G.Armstrong Whitworth \& Co. After Armstrong's death a further merger with Vickers Ltd formed Vickers Armstrong Ltd.In 1879 Armstrong took a great interest in Joseph Swan's invention of the incandescent electric light-bulb. He was one of those who formed the Swan Electric Light Company, opening a factory at South Benwell to make the bulbs. At Cragside, his mansion at Roth bury, he installed a water turbine and generator, making it one of the first houses in England to be lit by electricity.Armstrong was a noted philanthropist, building houses for his workforce, and endowing schools, hospitals and parks. His last act of charity was to purchase Bamburgh Castle, Northumbria, in 1894, intending to turn it into a hospital or a convalescent home, but he did not live long enough to complete the work.[br]Principal Honours and DistinctionsKnighted 1859. FRS 1846. President, Institution of Mechanical Engineers; Institution of Civil Engineers; British Association for the Advancement of Science 1863. Baron Armstrong of Cragside 1887.Further ReadingE.R.Jones, 1886, Heroes of Industry', London: Low.D.J.Scott, 1962, A History of Vickers, London: Weidenfeld \& Nicolson.IMcNBiographical history of technology > Armstrong, Sir William George, Baron Armstrong of Cragside
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110 Arsonval, Jacques Arsène d'
SUBJECT AREA: Medical technology[br]b. 8 June 1851 Boric, Franced. 31 December 1940 Boric, France[br]French physician and physicist noted for his invention of the reflecting galvanometer and for contributions to electrotherapy.[br]After studies at colleges in Limoges and later in Paris, Arsonval became a doctor of medicine in 1877. In 1882 the Collège de France established a laboratory of biophysics with Arsonval as Director, and he was Professor from 1894.His most outstanding scientific contributions were in the field of biological applications of electricity. His interest in muscle currents led to a series of inventions to assist in research, including the moving-coil galvanometer. In 1881 he made a significant improvement to the galvanometer by reversing the magnetic elements. It had been usual to suspend a compass needle in the centre of a large, stationary coil, but Arsonval's invention was to suspend a small, light coil between the poles of a powerful fixed magnet. This simple arrangement was independent of the earth's magnetic field and insensitive to vibration. A great increase in sensitivity was achieved by attaching a mirror to the coil in order to reflect a spot of light. For bacterial-research purposes he designed the first constant-temperature incubator controlled by electricity. His experiments on the effects of high-frequency, low-voltage alternating currents on animals led to the first high-frequency heat-therapy unit being established in 1892, and later to methods of physiotherapy becoming a professional discipline.[br]Principal Honours and DistinctionsAcadémie des Sciences, Prix Montyon 1882. Chevalier de la Légion d'honneur 1884. Grand Cross 1931.Bibliography1882, Comptes rendus de l'Académie des Sciences 94:1347–50 (describes the galvanometer).1903, Traité de physique biologique, 2 vols, Paris (an account of his technological work).Further ReadingC.C.Gillispie (ed.), 1970, Dictionary of Scientific Biography, Vol. 1, New York, pp. 302–5.D.O.Woodbury, 1949, A Measure for Greatness, New York.GWBiographical history of technology > Arsonval, Jacques Arsène d'
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111 Arup, Sir Ove
SUBJECT AREA: Architecture and building[br]b. 16 April 1895 Newcastle upon Tyne, Englandd. 5 February 1988 Highgate, London, England[br]English consultant engineer.[br]Of Scandinavian parentage, Arup attended school in Germany and Denmark before taking his degree in mathematics and philosophy at Copenhagen University in 1914. He then graduated as a civil engineer from the Royal Technical College in the same city, specializing in the theory of structures.Arup retained close ties with Europe for some time, working in Hamburg as a designer for the Danish civil engineering firm of Christiani \& Nielsen. Then, in the 1930s, he began what was to be a long career in England as an engineering consultant to a number of architects who were beginning to build with modern materials (par-ticularly concrete) and methods of construction. He became consultant to the famous firm of Tecton (under the direction of Berthold Lubetkin) and was closely associated with the leading projects of that firm at the time, notably the High-point flats at Highgate, the Finsbury Health Centre and the award-winning Penguin Pool at the Regent's Park Zoological Gardens, all in London.In 1945 Arup founded his own firm, Ove Arup \& Partners, working entirely as a consultant to architects, particularly on structural schemes, and in 1963 he set up a partnership of architects and engineers, Arup Associates. The many and varied projects with which he was concerned included Coventry Cathedral and the University of Sussex with Sir Basil Spence, the Sydney Opera House with Joern Utzon and St Catherine's College, Oxford, with Arne Jacobsen.[br]Principal Honours and DistinctionsCBE 1953. Commander of the Order of Danneborg, awarded by King Frederik of Denmark, 1975. Honorary Doctorate Tekniske Hojskole, Lyngby, Denmark 1954. Honorary DSc Durham University 1967, University of East Anglia 1968, Heriot-Watt University 1976. RIBA Gold Medal 1966. Institution of Structural Engineers Gold Medal 1973. Fellow of the American Concrete Institution 1975.Further ReadingJ.M.Richards, 1953, An Introduction to Modern Architecture, London: Penguin. H.Russell-Hitchcock, 1982, Architecture, Nineteenth and Twentieth Centuries, London: Pelican.C.Jencks, 1980, Late-Modern Architecture, London: Academy Editions.DY -
112 Aspinall, Sir John Audley Frederick
[br]b. 25 August 1851 Liverpool, Englandd. 19 January 1937 Woking, England[br]English mechanical engineer, pioneer of the automatic vacuum brake for railway trains and of railway electrification.[br]Aspinall's father was a QC, Recorder of Liverpool, and Aspinall himself became a pupil at Crewe Works of the London \& North Western Railway, eventually under F.W. Webb. In 1875 he was appointed Manager of the works at Inchicore, Great Southern \& Western Railway, Ireland. While he was there, some of the trains were equipped, on trial, with continuous brakes of the non-automatic vacuum type. Aspinall modified these to make them automatic, i.e. if the train divided, brakes throughout both parts would be applied automatically. Aspinall vacuum brakes were subsequently adopted by the important Great Northern, Lancashire \& Yorkshire, and London \& North Western Railways.In 1883, aged only 32, Aspinall was appointed Locomotive Superintendent of the Great Southern \& Western Railway, but in 1886 he moved in the same capacity to the Lancashire \& Yorkshire Railway, where his first task was to fit out the new works at Horwich. The first locomotive was completed there in 1889, to his design. In 1899 he introduced a 4–4–2, the largest express locomotive in Britain at the time, some of which were fitted with smokebox superheaters to Aspinall's design.Unusually for an engineer, in 1892 Aspinall was appointed General Manager of the Lancashire \& Yorkshire Railway. He electrified the Liverpool-Southport line in 1904 at 600 volts DC with a third rail; this was an early example of main-line electrification, for it extended beyond the Liverpool suburban area. He also experimented with 3,500 volt DC overhead electrification of the Bury-Holcombe Brook branch in 1913, but converted this to 1,200 volts DC third rail to conform with the Manchester-Bury line when this was electrified in 1915. In 1918 he was made a director of the Lancashire \& Yorkshire Railway.[br]Principal Honours and DistinctionsKnighted 1917. President, Institution of Mechanical Engineers 1909. President, Institution of Civil Engineers 1918.Further ReadingH.A.V.Bulleid, 1967, The Aspinall Era, Shepperton: Ian Allan (provides a good account of Aspinall and his life's work).C.Hamilton Ellis, 1958, Twenty Locomotive Men, Shepperton: Ian Allan, Ch. 19 (a good brief account).PJGRBiographical history of technology > Aspinall, Sir John Audley Frederick
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113 Atwood, George
SUBJECT AREA: Ports and shipping[br]b. 1746 Englandd. July 1807 London, England[br]English mathematician author of a theory on ship stability.[br]Atwood was educated at Westminster School and entered Trinity College, Cambridge, in 1765 with a scholarship. He graduated with high honours (third wrangler) in 1796, and went on to become a fellow and tutor of his college. In 1776 he was elected Fellow of the Royal Society. Eight years later, William Pitt the Younger (1759–1806) appointed him a senior officer of the Customs, this being a means of reimbursing him for the arduous and continuing task of calculating the national revenue. As a lecturer he was greatly renowned and his abilities as a calculator and as a musician were of a high order.In the late 1790s Atwood presented a paper to the Royal Society that showed a means of obtaining the righting lever on a ship inclined from the vertical; this was a major step forward in the study of ship stability. Among his other inventions was a machine to exhibit the accelerative force of gravity.[br]Principal Honours and DistinctionsFRS 1776.Further ReadingA.M.Robb, 1952, Theory of Naval Architecture, London: Charles Griffin (for a succinct description of the various factors in ship stability, and the importance of Atwood's contribution).FMW -
114 Austin, Herbert, Baron Austin
[br]b. 8 November 1866 Little Missenden, Buckinghamshire, Englandd. 23 May 1941 Lickey Grange, near Bromsgrove, Herefordshire, England[br]English manufacturer of cars.[br]The son of Stephen (or Steven) Austin, a farmer of Wentworth, Yorkshire, he was educated at Rotherham Grammar School and then went to Australia with an uncle in 1884. There he became apprenticed as an engineer at the Langlands Foundry in Melbourne. He moved to the Wolseley Sheep Shearing Company, and soon after became its Manager; in 1893 he returned to England, where he became Production Manager to the English branch of the same company in Birmingham. The difficulties of travel in Australia gave him an idea of the advantages of motor-driven vehicles, and in 1895 he produced the first Wolseley car. In 1901 he was appointed to the Wolseley board, and from 1911 he was Chairman.His first car was a three-wheeler. An improved model was soon available, and in 1901 the Wolseley company took over the machine tool and motor side of Vickers Sons and Maxim and traded under the name of the Wolseley Tool and Motor Car Company. Herbert Austin was the General Manager. In 1905 he decided to start his own company and formed the Austin Motor Company Ltd, with works at Longbridge, near Birmingham. With a workforce of 270, the firm produced 120 cars in 1906; by 1914 a staff of 2,000 were producing 1,000 cars a year. The First World War saw production facilities turned over to the production of aeroplanes, guns and ammunition.Peacetime brought a return to car manufacture, and 1922 saw the introduction of the 7 hp "Baby Austin", a car for the masses. Many other models followed. By 1937 the original Longbridge factory had grown to 220 acres, and the staff had increased to over 16,000, while the number of cars produced had grown to 78,000 per year.Herbert Austin was a philanthropist who endowed many hospitals and not a few universities; he was created a Baron in 1936.[br]Principal Honours and DistinctionsBaron 1936.Further Reading1941, Austin Magazine (June).IMcNBiographical history of technology > Austin, Herbert, Baron Austin
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115 Ayre, Sir Amos Lowrey
SUBJECT AREA: Ports and shipping[br]b. 23 July 1885 South Shields, Englandd. 13 January 1952 London, England[br]English shipbuilder and pioneer of the inter-war "economy" freighters; Chairman of the Shipbuilding Conference.[br]Amos Ayre grew up on the Tyne with the stimulus of shipbuilding and seafaring around him. After an apprenticeship as a ship draughtsman and distinction in his studies, he held responsible posts in the shipyards of Belfast and later Dublin. His first dramatic move came in 1909 when he accepted the post of Manager of the new Employment Exchange at Govan, then just outside Glasgow. During the First World War he was in charge of fleet coaling operations on the River Forth, and later was promoted Admiralty District Director for shipyard labour in Scotland.Before the conclusion of hostilities, with his brother Wilfrid (later Sir Wilfrid Ayre) he founded the Burntisland Shipbuilding Company in Fife. Setting up on a green field site allowed the brothers to show innovation in design, production and marketing. Such was their success that the new yard was busy throughout the Depression, building standard ships which incorporated low operating costs with simplicity of construction.Through public service culminating in the 1929 Safety of Life at Sea Conference, Amos Ayre became recognized not only as an eminent naval architect, but also as a skilled negotiator. In 1936 he was invited to become Chairman of the Shipbuilding Conference and thereby virtual leader of the industry. As war approached he planned with meticulous care the rearrangement of national shipbuilding capacity, enabling Britain to produce standard hulls ranging from the legendary TID tugs to the standard freighters built in Sunderland or Port Glasgow. In 1939 he became Director of Merchant Shipbuilding, a position he held until 1944, when with typical foresight he asked to be released to plan for shipbuilding's return to normality.[br]Principal Honours and DistinctionsKnighted 1937. KBE 1943. Officer of the Order of Orange-Nassau.Bibliography1919, "The theory and design of British shipbuilding", The Syren and Shipping, London.Further ReadingWilfrid Ayre, 1968, A Shipbuilders Yesterdays, Fife (published privately). James Reid, 1964, James Lithgow, Master of Work, London.Maurice E.Denny, 1955, "The man and his work" (First Amos Ayre Lecture), Transactions of the Institution of Naval Architects vol. 97.FMW -
116 Ayrton, William Edward
[br]b. 14 September 1847 London, Englandd. 8 November 1908 London, England[br]English physicist, inventor and pioneer in technical education.[br]After graduating from University College, London, Ayrton became for a short time a pupil of Sir William Thomson in Glasgow. For five years he was employed in the Indian Telegraph Service, eventually as Superintendent, where he assisted in revolutionizing the system, devising methods of fault detection and elimination. In 1873 he was invited by the Japanese Government to assist as Professor of Physics and Telegraphy in founding the Imperial College of Engineering in Tokyo. There he created a teaching laboratory that served as a model for those he was later to organize in England and which were copied elsewhere. It was in Tokyo that his joint researches with Professor John Perry began, an association that continued after their return to England. In 1879 he became Professor of Technical Physics at the City and Guilds Institute in Finsbury, London, and later was appointed Professor of Physics at the Central Institution in South Kensington.The inventions of Avrton and Perrv included an electric tricycle in 1882, the first practicable portable ammeter and other electrical measuring instruments. By 1890, when the research partnership ended, they had published nearly seventy papers in their joint names, the emphasis being on a mathematical treatment of subjects including electric motor design, construction of electrical measuring instruments, thermodynamics and the economical use of electric conductors. Ayrton was then employed as a consulting engineer by government departments and acted as an expert witness in many important patent cases.[br]Principal Honours and DistinctionsFRS 1881. President, Physical Society 1890–2. President, Institution of Electrical Engineers 1892. Royal Society Royal Medal 1901.Bibliography28 April 1883, British patent no. 2,156 (Ayrton and Perry's ammeter and voltmeter). 1887, Practical Electricity, London (based on his early laboratory courses; 7 edns followed during his lifetime).1892, "Electrotechnics", Journal of the Institution of Electrical Engineers 21, 5–36 (for a survey of technical education).Further ReadingD.W.Jordan, 1985, "The cry for useless knowledge: education for a new Victorian technology", Proceedings of the Institution of Electrical Engineers, 132 (Part A): 587– 601.G.Gooday, 1991, History of Technology, 13: 73–111 (for an account of Ayrton and the teaching laboratory).GW -
117 Babbage, Charles
SUBJECT AREA: Electronics and information technology[br]b. 26 December 1791 Walworth, Surrey, Englandd. 18 October 1871 London, England[br]English mathematician who invented the forerunner of the modern computer.[br]Charles Babbage was the son of a banker, Benjamin Babbage, and was a sickly child who had a rather haphazard education at private schools near Exeter and later at Enfield. Even as a child, he was inordinately fond of algebra, which he taught himself. He was conversant with several advanced mathematical texts, so by the time he entered Trinity College, Cambridge, in 1811, he was ahead of his tutors. In his third year he moved to Peterhouse, whence he graduated in 1814, taking his MA in 1817. He first contributed to the Philosophical Transactions of the Royal Society in 1815, and was elected a fellow of that body in 1816. He was one of the founders of the Astronomical Society in 1820 and served in high office in it.While he was still at Cambridge, in 1812, he had the first idea of calculating numerical tables by machinery. This was his first difference engine, which worked on the principle of repeatedly adding a common difference. He built a small model of an engine working on this principle between 1820 and 1822, and in July of the latter year he read an enthusiastically received note about it to the Astronomical Society. The following year he was awarded the Society's first gold medal. He submitted details of his invention to Sir Humphry Davy, President of the Royal Society; the Society reported favourably and the Government became interested, and following a meeting with the Chancellor of the Exchequer Babbage was awarded a grant of £1,500. Work proceeded and was carried on for four years under the direction of Joseph Clement.In 1827 Babbage went abroad for a year on medical advice. There he studied foreign workshops and factories, and in 1832 he published his observations in On the Economy of Machinery and Manufactures. While abroad, he received the news that he had been appointed Lucasian Professor of Mathematics at Cambridge University. He held the Chair until 1839, although he neither resided in College nor gave any lectures. For this he was paid between £80 and £90 a year! Differences arose between Babbage and Clement. Manufacture was moved from Clement's works in Lambeth, London, to new, fireproof buildings specially erected by the Government near Babbage's house in Dorset Square, London. Clement made a large claim for compensation and, when it was refused, withdrew his workers as well as all the special tools he had made up for the job. No work was possible for the next fifteen months, during which Babbage conceived the idea of his "analytical engine". He approached the Government with this, but it was not until eight years later, in 1842, that he received the reply that the expense was considered too great for further backing and that the Government was abandoning the project. This was in spite of the demonstration and perfectly satisfactory operation of a small section of the analytical engine at the International Exhibition of 1862. It is said that the demands made on manufacture in the production of his engines had an appreciable influence in improving the standard of machine tools, whilst similar benefits accrued from his development of a system of notation for the movements of machine elements. His opposition to street organ-grinders was a notable eccentricity; he estimated that a quarter of his mental effort was wasted by the effect of noise on his concentration.[br]Principal Honours and DistinctionsFRS 1816. Astronomical Society Gold Medal 1823.BibliographyBabbage wrote eighty works, including: 1864, Passages from the Life of a Philosopher.July 1822, Letter to Sir Humphry Davy, PRS, on the Application of Machinery to the purpose of calculating and printing Mathematical Tables.Further Reading1961, Charles Babbage and His Calculating Engines: Selected Writings by Charles Babbage and Others, eds Philip and Emily Morrison, New York: Dover Publications.IMcN -
118 Bacon, Francis Thomas
SUBJECT AREA: Aerospace[br]b. 21 December 1904 Billericay, Englandd. 24 May 1992 Little Shelford, Cambridge, England[br]English mechanical engineer, a pioneer in the modern phase of fuel-cell development.[br]After receiving his education at Eton and Trinity College, Cambridge, Bacon served with C.A. Parsons at Newcastle upon Tyne from 1925 to 1940. From 1946 to 1956 he carried out research on Hydrox fuel cells at Cambridge University and was a consultant on fuel-cell design to a number of organizations throughout the rest of his life.Sir William Grove was the first to observe that when oxygen and hydrogen were supplied to platinum electrodes immersed in sulphuric acid a current was produced in an external circuit, but he did not envisage this as a practical source of electrical energy. In the 1930s Bacon started work to develop a hydrogen-oxygen fuel cell that operated at moderate temperatures and pressures using an alkaline electrolyte. In 1940 he was appointed to a post at King's College, London, and there, with the support of the Admiralty, he started full-time experimental work on fuel cells. His brief was to produce a power source for the propulsion of submarines. The following year he was posted as a temporary experimental officer to the Anti-Submarine Experimental Establishment at Fairlie, Ayrshire, and he remained there until the end of the Second World War.In 1946 he joined the Department of Chemical Engineering at Cambridge, receiving a small amount of money from the Electrical Research Association. Backing came six years later from the National Research and Development Corporation (NRDC), the development of the fuel cell being transferred to Marshalls of Cambridge, where Bacon was appointed Consultant.By 1959, after almost twenty years of individual effort, he was able to demonstrate a 6 kW (8 hp) power unit capable of driving a small truck. Bacon appreciated that when substantial power was required over long periods the hydrogen-oxygen fuel cell associated with high-pressure gas storage would be more compact than conventional secondary batteries.The development of the fuel-cell system pioneered by Bacon was stimulated by a particular need for a compact, lightweight source of power in the United States space programme. Electro-chemical generators using hydrogen-oxygen cells were chosen to provide the main supplies on the Apollo spacecraft for landing on the surface of the moon in 1969. An added advantage of the cells was that they simultaneously provided water. NRDC was largely responsible for the forma-tion of Energy Conversion Ltd, a company that was set up to exploit Bacon's patents and to manufacture fuel cells, and which was supported by British Ropes Ltd, British Petroleum and Guest, Keen \& Nettlefold Ltd at Basingstoke. Bacon was their full-time consultant. In 1971 Energy Conversion's operation was moved to the UK Atomic Energy Research Establishment at Harwell, as Fuel Cells Ltd. Bacon remained with them until he retired in 1973.[br]Principal Honours and DistinctionsOBE 1967. FRS 1972. Royal Society S.G. Brown Medal 1965. Royal Aeronautical Society British Silver Medal 1969.Bibliography27 February 1952, British patent no. 667,298 (hydrogen-oxygen fuel cell). 1963, contribution in W.Mitchell (ed.), Fuel Cells, New York, pp. 130–92.1965, contribution in B.S.Baker (ed.), Hydrocarbon Fuel Cell Technology, New York, pp. 1–7.Further ReadingObituary, 1992, Daily Telegraph (8 June).A.McDougal, 1976, Fuel Cells, London (makes an acknowledgement of Bacon's contribution to the design and application of fuel cells).D.P.Gregory, 1972, Fuel Cells, London (a concise introduction to fuel-cell technology).GW -
119 Baekeland, Leo Hendrik
[br]b. 14 November 1863 Saint-Martens-Latern, Belgiumd. 23 February 1944 Beacon, New York, USA[br]Belgian/American inventor of the Velox photographic process and the synthetic plastic Bakélite.[br]The son of an illiterate shoemaker, Baekeland was first apprenticed in that trade, but was encouraged by his mother to study, with spectacular results. He won a scholarship to Gand University and graduated in chemistry. Before he was 21 he had achieved his doctorate, and soon afterwards he obtained professorships at Bruges and then at Gand. Baekeland seemed set for a distinguished academic career, but he turned towards the industrial applications of chemistry, especially in photography.Baekeland travelled to New York to further this interest, but his first inventions met with little success so he decided to concentrate on one that seemed to have distinct commercial possibilities. This was a photographic paper that could be developed in artificial light; he called this "gas light" paper Velox, using the less sensitive silver chloride as a light-sensitive agent. It proved to have good properties and was easy to use, at a time of photography's rising popularity. By 1896 the process began to be profitable, and three years later Baekeland disposed of his plant to Eastman Kodak for a handsome sum, said to be $3–4 million. That enabled him to retire from business and set up a laboratory at Yonkers to pursue his own research, including on synthetic resins. Several chemists had earlier obtained resinous products from the reaction between phenol and formaldehyde but had ignored them. By 1907 Baekeland had achieved sufficient control over the reaction to obtain a good thermosetting resin which he called "Bakélite". It showed good electrical insulation and resistance to chemicals, and was unchanged by heat. It could be moulded while plastic and would then set hard on heating, with its only drawback being its brittleness. Bakelite was an immediate success in the electrical industry and Baekeland set up the General Bakelite Company in 1910 to manufacture and market the product. The firm grew steadily, becoming the Bakélite Corporation in 1924, with Baekeland still as active President.[br]Principal Honours and DistinctionsPresident, Electrochemical Society 1909. President, American Chemical Society 1924. Elected to the National Academy of Sciences 1936.Further ReadingJ.Gillis, 1965, Leo Baekeland, Brussels.A.R.Matthis, 1948, Leo H.Baekeland, Professeur, Docteur ès Sciences, chimiste, inventeur et grand industriel, Brussels.J.K.Mumford, 1924, The Story of Bakélite.C.F.Kettering, 1947, memoir on Baekeland, Biographical Memoirs of the National Academy of Sciences 24 (includes a list of his honours and publications).LRD -
120 Bailey, Sir Donald Coleman
SUBJECT AREA: Civil engineering[br]b. 15 September 1901 Rotherham, Yorkshire, Englandd. 5 May 1985 Bournemouth, Dorset, England[br]English engineer, designer of the Bailey bridge.[br]Bailey was educated at the Leys School, Cambridge, before going to Sheffield University where he studied for a degree in engineering. He joined the Civil Service in 1928 and was posted to the staff of the Experimental Bridging Establishment of the Ministry of Supply at Christchurch, Hampshire. There he continued his boyhood hobby of making model bridges of wood and string. He evolved a design for a prefabricated metal bridge assembled from welded panels linked by pinned joints; this became known as the Bailey bridge. Its design was accepted by the War Office in 1941 and from then on it was used throughout the subsequent conflict of the Second World War. It was a great improvement on its predecessor, the Inglis bridge, designed by a Cambridge University professor of engineering, Charles Inglis, with tubular members that were 10 or 12 ft (3.66 m) long; this bridge was notoriously difficult to construct, particularly in adverse weather conditions, whereas the Bailey bridge's panels and joints were far more manageable and easy to assemble. The simple and standardized component parts of the Bailey bridge made it highly adaptable: it could be strengthened by increasing the number of truss girders, and wide rivers could be crossed by a series of Bailey bridges connected by pontoons. Field Marshal Montgomery is recorded as saying that without the Bailey bridge we should not have won the war'.[br]Principal Honours and DistinctionsKnighted 1946.Further ReadingObituary, 1985, The Guardian 6 May.IMcNBiographical history of technology > Bailey, Sir Donald Coleman
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Subject — Sub*ject , n. [From L. subjectus, through an old form of F. sujet. See {Subject}, a.] 1. That which is placed under the authority, dominion, control, or influence of something else. [1913 Webster] 2. Specifically: One who is under the authority… … The Collaborative International Dictionary of English
principal — prin·ci·pal 1 / prin sə pəl/ adj 1: being the main or most important, consequential, or influential their principal place of business the principal obligor 2: of, relating to, or constituting principal or a principal the principal amount of the… … Law dictionary
subject — n 1 *citizen, national Antonyms: sovereign 2 Subject, matter, subject matter, argument, topic, text, theme, motive, motif, leitmotiv can mean the basic idea or the principal object of thought or attention in a discourse or artistic composition.… … New Dictionary of Synonyms
principal — [prin′sə pəl] adj. [OFr < L principalis < princeps: see PRINCE] 1. first in rank, authority, importance, degree, etc. 2. that is or has to do with PRINCIPAL (n. 3) n. 1. a principal person or thing; specif., a) a ch … English World dictionary
subject — [adj] at the mercy of; answerable accountable, apt, at one’s feet*, bound by, captive, collateral, conditional, contingent, controlled, dependent, directed, disposed, enslaved, exposed, governed, in danger of, inferior, liable, likely, obedient,… … New thesaurus
principal — adj Chief; leading; most important or considerable; primary; original. Highest in rank, authority, character, importance, or degree. As to principal challenge principal contract principal obligation principal office principal vein, see those… … Black's law dictionary
Principal homogeneous space — In mathematics, a principal homogeneous space, or torsor, for a group G is a set X on which G acts freely and transitively. That is, X is a homogeneous space for G such that the stabilizer of any point is trivial. An analogous definition holds in … Wikipedia
Principal at risk notes — What are Principal at Risk Notes? Ending Value Higher Benefits of PARs * Enhanced/Leveraged Return ** Upside: Receive a return that is enhanced by leverage so that it will be higher than the actually return, subject to any caps. ** Downside:… … Wikipedia
principal — principalship, n. /prin seuh peuhl/, adj. 1. first or highest in rank, importance, value, etc.; chief; foremost. 2. of, of the nature of, or constituting principal or capital: a principal investment. 3. Geom. (of an axis of a conic) passing… … Universalium
subject — subjectable, adj. subjectability, n. subjectedly, adv. subjectedness, n. subjectless, adj. subjectlike, adj. n., adj. /sub jikt/; v. /seuhb jekt /, n. 1. that which forms a basic matter of thought, discussion, investigation, etc.: a subject of… … Universalium
subject — sub•ject n., adj. [[t]ˈsʌb dʒɪkt[/t]] v. [[t]səbˈdʒɛkt[/t]] n. 1) that which forms a basic matter of thought, discussion, investigation, etc 2) edu a branch of knowledge as a course of study 3) a motive, cause, or ground: a subject for… … From formal English to slang
