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121 Heaviside, Oliver
[br]b. 18 May 1850 London, Englandd. 2 February 1925 Torquay, Devon, England[br]English physicist who correctly predicted the existence of the ionosphere and its ability to reflect radio waves.[br]Brought up in poor, almost Dickensian, circumstances, at the age of 13 years Heaviside, a nephew by marriage of Sir Charles Wheatstone, went to Camden House Grammar School. There he won a medal for science, but he was forced to leave because his parents could not afford the fees. After a year of private study, he began his working life in Newcastle in 1870 as a telegraph operator for an Anglo-Dutch cable company, but he had to give up after only four years because of increasing deafness. He therefore proceeded to spend his time studying theoretical aspects of electrical transmission and communication, and moved to Devon with his parents in 1889. Because the operation of many electrical circuits involves transient phenomena, he found it necessary to develop what he called operational calculus (which was essentially a form of the Laplace transform calculus) in order to determine the response to sudden voltage and current changes. In 1893 he suggested that the distortion that occurred on long-distance telephone lines could be reduced by adding loading coils at regular intervals, thus creating a matched-transmission line. Between 1893 and 1912 he produced a series of writings on electromagnetic theory, in one of which, anticipating a conclusion of Einstein's special theory of relativity, he put forward the idea that the mass of an electric charge increases with its velocity. When it was found that despite the curvature of the earth it was possible to communicate over very great distances using radio signals in the so-called "short" wavebands, Heaviside suggested the presence of a conducting layer in the ionosphere that reflected the waves back to earth. Since a similar suggestion had been made almost at the same time by Arthur Kennelly of Harvard, this layer became known as the Kennelly-Heaviside layer.[br]Principal Honours and DistinctionsFRS 1891. Institution of Electrical Engineers Faraday Medal 1924. Honorary PhD Gottingen. Honorary Member of the American Association for the Advancement of Science.Bibliography1872. "A method for comparing electro-motive forces", English Mechanic (July).1873. Philosophical Magazine (February) (a paper on the use of the Wheatstone Bridge). 1889, Electromagnetic Waves.1892, Electrical Papers.1893–1912, Electromagnetic Theory.Further ReadingI.Catt (ed.), 1987, Oliver Heaviside, The Man, St Albans: CAM Publishing.P.J.Nahin, 1988, Oliver Heaviside, Sage in Solitude: The Life and Works of an Electrical Genius of the Victorian Age, Institute of Electrical and Electronics Engineers, New York.J.B.Hunt, The Maxwellians, Ithaca: Cornell University Press.See also: Appleton, Sir Edward VictorKF -
122 Héroult, Paul Louis Toussaint
SUBJECT AREA: Metallurgy[br]b. 1863 Thury-Harcourt, Caen, Franced. 9 May 1914 Antibes, France[br]French metallurigst, inventor of the process of aluminium reduction by electrolysis.[br]Paul Héroult, the son of a tanner, at the age of 16, while still at school in Caen, read Deville's book on aluminium and became obsessed with the idea of developing a cheap way of producing this metal. After his family moved to Gentillysur-Bièvre he studied at the Ecole Sainte-Barbe in Paris and then returned to Caen to work in the laboratory of his father's tannery. His first patent, filed in February and granted on 23 April 1886, described an invention almost identical to that of C.M. Hall: "the electrolysis of alumina dissolved in molten cryolite into which the current is introduced through suitable electrodes. The cryolite is not consumed." Early in 1887 Héroult attempted to obtain the support of Alfred Rangod Pechiney, the proprietor of the works at Salindres where Deville's process for making sodium-reduced aluminium was still being operated. Pechiney persuaded Héroult to modify his electrolytic process by using a cathode of molten copper, thus making it possible produce aluminium bronze rather than pure aluminium. Héroult then approached the Swiss firm J.G.Nehe Söhne, ironmasters, whose works at the Falls of Schaffhausen obtained power from the Rhine. They were looking for a new metallurgical process requiring large quantities of cheap hydroelectric power and Héroult's process seemed suitable. In 1887 they established the Société Metallurgique Suisse to test Héroult's process. Héroult became Technical Director and went to the USA to defend his patents against those of Hall. During his absence the Schaffhausen trials were successfully completed, and on 18 November 1888 the Société Metallurgique combined with the German AEG group, Oerlikon and Escher Wyss, to establish the Aluminium Industrie Aktiengesellschaft Neuhausen. In the early electrolytic baths it was occasionally found that arcs between the bath surface and electrode could develop if the electrodes were inadvertently raised. From this observation, Héroult and M.Killiani developed the electric arc furnace. In this, arcs were intentionally formed between the surface of the charge and several electrodes, each connected to a different pole of the AC supply. This furnace, the prototype of the modern electric steel furnace, was first used for the direct reduction of iron ore at La Praz in 1903. This work was undertaken for the Canadian Government, for whom Héroult subsequently designed a 5,000-amp single-phase furnace which was installed and tested at Sault-Sainte-Marie in Ontario and successfully used for smelting magnetite ore.[br]Further ReadingAluminium Industrie Aktiengesellschaft Neuhausen, 1938, The History of the Aluminium-Industrie-Aktien-Gesellschaft Neuhausen 1888–1938, 2 vols, Neuhausen.C.J.Gignoux, Histoire d'une entreprise française. "The Hall-Héroult affair", 1961, Metal Bulletin (14 April):1–4.ASDBiographical history of technology > Héroult, Paul Louis Toussaint
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123 Hertz, Heinrich Rudolph
[br]b. 22 February 1857 Hamburg, Germanyd. 1 January 1894 Bonn, Germany[br]German physicist who was reputedly the first person to transmit and receive radio waves.[br]At the age of 17 Hertz entered the Gelehrtenschule of the Johaneums in Hamburg, but he left the following year to obtain practical experience for a year with a firm of engineers in Frankfurt am Main. He then spent six months at the Dresden Technical High School, followed by year of military service in Berlin. At this point he decided to switch from engineering to physics, and after a year in Munich he studied physics under Helmholtz at the University of Berlin, gaining his PhD with high honours in 1880. From 1883 to 1885 he was a privat-dozent at Kiel, during which time he studied the electromagnetic theory of James Clerk Maxwell. In 1885 he succeeded to the Chair in Physics at Karlsruhe Technical High School. There, in 1887, he constructed a rudimentary transmitter consisting of two 30 cm (12 in.) rods with metal balls separated by a 7.5 mm (0.3 in.) gap at the inner ends and metallic plates at the outer ends, the whole assembly being mounted at the focus of a large parabolic metal mirror and the two rods being connected to an induction coil. At the other side of his laboratory he placed a 70 cm (27½ in.) diameter wire loop with a similar air gap at the focus of a second metal mirror. When the induction coil was made to create a spark across the transmitter air gap, he found that a spark also occurred at the "receiver". By a series of experiments he was not only able to show that the invisible waves travelled in straight lines and were reflected by the parabolic mirrors, but also that the vibrations could be refracted like visible light and had a similar wavelength. By this first transmission and reception of radio waves he thus confirmed the theoretical predictions made by Maxwell some twenty years earlier. It was probably in his experiments with this apparatus in 1887 that Hertz also observed that the voltage at which a spark was able to jump a gap was significantly reduced by the presence of ultraviolet light. This so-called photoelectric effect was subsequently placed on a theoretical basis by Albert Einstein in 1905. In 1889 he became Professor of Physics at the University of Bonn, where he continued to investigate the nature of electric discharges in gases at low pressure until his death after a long and painful illness. In recognition of his measurement of radio and other waves, the international unit of frequency of an oscillatory wave, the cycle per second, is now universally known as the Hertz.[br]Principal Honours and DistinctionsRoyal Society Rumford Medal 1890.BibliographyMuch of Hertz's work, including his 1890 paper "On the fundamental equations of electrodynamics for bodies at rest", is recorded in three collections of his papers which are available in English translations by D.E.Jones et al., namely Electric Waves (1893), Miscellaneous Papers (1896) and Principles of Mechanics (1899).Further ReadingJ.G.O'Hara and W.Pricha, 1987, Hertz and the Maxwellians, London: Peter Peregrinus. J.Hertz, 1977, Heinrich Hertz, Memoirs, Letters and Diaries, San Francisco: San Francisco Press.R.Appleyard, 1930, Pioneers of Electrical Communication.See also: Heaviside, OliverKFBiographical history of technology > Hertz, Heinrich Rudolph
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124 Holmes, Frederic Hale
[br]fl. 1850s–60s[br]British engineer who pioneered the electrical illumination of lighthouses in Great Britain.[br]An important application of the magneto generator was demonstrated by Holmes in 1853 when he showed that it might be used to supply an arc lamp. This had many implications for the future because it presented the possibility of making electric lighting economically successful. In 1856 he patented a machine with six disc armatures on a common axis rotating between seven banks of permanent magnets. The following year Holmes suggested the possible application of his invention to lighthouse illumination and a trial was arranged and observed by Faraday, who was at that time scientific adviser to Trinity House, the corporation entrusted with the care of light-houses in England and Wales. Although the trial was successful and gained the approval of Faraday, the Elder Brethren of Trinity House imposed strict conditions on Holmes's design for machines to be used for a more extensive trial. These included connecting the machine directly to a slow-speed steam engine, but this resulted in a reduced performance. The experiments of Holmes and Faraday were brought to the attention of the French lighthouse authorities and magneto generators manufactured by Société Alliance began to be installed in some lighthouses along the coast of France. After noticing the French commutatorless machines, Holmes produced an alternator of similar type in 1867. Two of these were constructed for a new lighthouse at Souter Point near Newcastle and two were installed in each of the two lighthouses at South Foreland. One of the machines from South Foreland that was in service from 1872 to 1922 is preserved in the Royal Museum of Scotland, Edinburgh. A Holmes generator is also preserved in the Science Museum, London. Holmes obtained a series of patents for generators between 1856 and 1869, with all but the last being of the magneto-electric type.[br]Bibliography7 March 1856, British patent no. 573 (the original patent for Holmes's invention).1863, "On magneto electricity and its application to lighthouse purposes", Journal of the Society of Arts 12:39–43.Further ReadingW.J.King, 1962, in The Development of Electrical Technology in the 19th Century; Washington, DC: Smithsonian Institution, Paper 30, pp. 351–63 (provides a detailed account of Holmes's generators).J.N.Douglas, 1879, "The electric light applied to lighthouse illumination", Proceedings of the Institution of Civil Engineers 57(3):77–110 (describes trials of Holmes's machines).GW -
125 Houldsworth, Henry
SUBJECT AREA: Textiles[br]b. 1797 Manchester (?), Englandd. 1868 Manchester (?), England[br]English cotton spinner who introduced the differential gear to roving frames in Britain.[br]There are two claimants for the person who originated the differential gear as applied to roving frames: one is J.Green, a tinsmith of Mansfield, in his patent of 1823; the other is Arnold, who had applied it in America and patented it in early 1823. This latter was the source for Houldsworth's patent in 1826. It seems that Arnold's gearing was secretly communicated to Houldsworth by Charles Richmond, possibly when Houldsworth visited the United States in 1822–3, but more probably in 1825 when Richmond went to England. In return, Richmond received information about parts of a cylinder printing machine from Houldsworth. In the working of the roving frame, as the rovings were wound onto their bobbins and the diameter of the bobbins increased, the bobbin speed had to be reduced to keep the winding on at the same speed while the flyers and drawing rollers had to maintain their initial speed. Although this could be achieved by moving the driving belt along coned pulleys, this method did not provide enough power and slippage occurred. The differential gear combined the direct drive from the main shaft of the roving frame with that from the cone drive, so that only the latter provided the dif-ference between flyer and bobbin speeds, i.e. the winding speeds, thus taking away most of the power from that belt. Henry Houldsworth Senior (1774–1853) was living in Manchester when his son Henry was born, but by 1800 had moved to Glasgow. He built several mills, including a massive one at Anderston, Scotland, in which a Boulton \& Watt steam engine was installed. Henry Houldsworth Junior was probably back in Manchester by 1826, where he was to become an influential cotton spinner as chief partner in his mills, which he moved out to Reddish in 1863–5. He was also a prominent landowner in Cheetham. When William Fairbairn was considering establishing the Association for the Prevention of Steam Boiler Explosions in 1854, he wanted to find an influential manufacturer and mill-owner and he made a happy choice when he turned to Henry Houldsworth for assistance.[br]Bibliography1826, British patent no. 5,316 (differential gear for roving frames).Further ReadingDetails about Henry Houldsworth Junior are very sparse. The best account of his acquisition of the differential gear is given by D.J.Jeremy, 1981, Transatlantic Industrial Revolution. The Diffusion of Textile Technologies Between Britain and America, 1790–1830, Oxford.W.English, 1969, The Textile Industry, London (an explanation of the mechanisms of the roving frame).W.Pole, 1877, The Life of Sir William Fairbairn, Bart., London (provides an account of the beginning of the Manchester Steam Users' Association for the Prevention of Steam-boiler Explosions).RLH -
126 Huygens, Christiaan
SUBJECT AREA: Horology[br]b. 14 April 1629 The Hague, the Netherlandsd. 8 June 1695 The Hague, the Netherlands[br]Dutch scientist who was responsible for two of the greatest advances in horology: the successful application of both the pendulum to the clock and the balance spring to the watch.[br]Huygens was born into a cultured and privileged class. His father, Constantijn, was a poet and statesman who had wide interests. Constantijn exerted a strong influence on his son, who was educated at home until he reached the age of 16. Christiaan studied law and mathematics at Ley den University from 1645 to 1647, and continued his studies at the Collegium Arausiacum in Breda until 1649. He then lived at The Hague, where he had the means to devote his time entirely to study. In 1666 he became a Member of the Académie des Sciences in Paris and settled there until his return to The Hague in 1681. He also had a close relationship with the Royal Society and visited London on three occasions, meeting Newton on his last visit in 1689. Huygens had a wide range of interests and made significant contributions in mathematics, astronomy, optics and mechanics. He also made technical advances in optical instruments and horology.Despite the efforts of Burgi there had been no significant improvement in the performance of ordinary clocks and watches from their inception to Huygens's time, as they were controlled by foliots or balances which had no natural period of oscillation. The pendulum appeared to offer a means of improvement as it had a natural period of oscillation that was almost independent of amplitude. Galileo Galilei had already pioneered the use of a freely suspended pendulum for timing events, but it was by no means obvious how it could be kept swinging and used to control a clock. Towards the end of his life Galileo described such a. mechanism to his son Vincenzio, who constructed a model after his father's death, although it was not completed when he himself died in 1642. This model appears to have been copied in Italy, but it had little influence on horology, partly because of the circumstances in which it was produced and possibly also because it differed radically from clocks of that period. The crucial event occurred on Christmas Day 1656 when Huygens, quite independently, succeeded in adapting an existing spring-driven table clock so that it was not only controlled by a pendulum but also kept it swinging. In the following year he was granted a privilege or patent for this clock, and several were made by the clockmaker Salomon Coster of The Hague. The use of the pendulum produced a dramatic improvement in timekeeping, reducing the daily error from minutes to seconds, but Huygens was aware that the pendulum was not truly isochronous. This error was magnified by the use of the existing verge escapement, which made the pendulum swing through a large arc. He overcame this defect very elegantly by fitting cheeks at the pendulum suspension point, progressively reducing the effective length of the pendulum as the amplitude increased. Initially the cheeks were shaped empirically, but he was later able to show that they should have a cycloidal shape. The cheeks were not adopted universally because they introduced other defects, and the problem was eventually solved more prosaically by way of new escapements which reduced the swing of the pendulum. Huygens's clocks had another innovatory feature: maintaining power, which kept the clock going while it was being wound.Pendulums could not be used for portable timepieces, which continued to use balances despite their deficiencies. Robert Hooke was probably the first to apply a spring to the balance, but his efforts were not successful. From his work on the pendulum Huygens was well aware of the conditions necessary for isochronism in a vibrating system, and in January 1675, with a flash of inspiration, he realized that this could be achieved by controlling the oscillations of the balance with a spiral spring, an arrangement that is still used in mechanical watches. The first model was made for Huygens in Paris by the clockmaker Isaac Thuret, who attempted to appropriate the invention and patent it himself. Huygens had for many years been trying unsuccessfully to adapt the pendulum clock for use at sea (in order to determine longitude), and he hoped that a balance-spring timekeeper might be better suited for this purpose. However, he was disillusioned as its timekeeping proved to be much more susceptible to changes in temperature than that of the pendulum clock.[br]Principal Honours and DistinctionsFRS 1663. Member of the Académie Royale des Sciences 1666.BibliographyFor his complete works, see Oeuvres complètes de Christian Huygens, 1888–1950, 22 vols, The Hague.1658, Horologium, The Hague; repub., 1970, trans. E.L.Edwardes, AntiquarianHorology 7:35–55 (describes the pendulum clock).1673, Horologium Oscillatorium, Paris; repub., 1986, The Pendulum Clock or Demonstrations Concerning the Motion ofPendula as Applied to Clocks, trans.R.J.Blackwell, Ames.The balance spring watch was first described in Journal des Sçavans 25 February 1675, and translated in Philosophical Transactions of the Royal Society (1675) 4:272–3.Further ReadingH.J.M.Bos, 1972, Dictionary of Scientific Biography, ed. C.C.Gillispie, Vol. 6, New York, pp. 597–613 (for a fuller account of his life and scientific work, but note the incorrect date of his death).R.Plomp, 1979, Spring-Driven Dutch Pendulum Clocks, 1657–1710, Schiedam (describes Huygens's application of the pendulum to the clock).S.A.Bedini, 1991, The Pulse of Time, Florence (describes Galileo's contribution of the pendulum to the clock).J.H.Leopold, 1982, "L"Invention par Christiaan Huygens du ressort spiral réglant pour les montres', Huygens et la France, Paris, pp. 154–7 (describes the application of the balance spring to the watch).A.R.Hall, 1978, "Horology and criticism", Studia Copernica 16:261–81 (discusses Hooke's contribution).DV -
127 Johansson, Carl Edvard
[br]b. 15 March 1864 Orebro, Swedend. 30 September 1943 Eskilstuna, Sweden[br]Swedish metrologist and inventor of measuring-gauge blocks.[br]Carl Edvard Johansson was first apprenticed to a shoemaker, but he soon abandoned that career. In 1882 he went to America to join his brother Arvid working at a sawmill in the summer; in winter the brothers obtained further general education at the Gustavus Adolphus College at St Peter, Minnesota. They returned to Sweden in November 1884 and in the following year Carl obtained employment with a small engineering firm which rented a workshop in the government small-arms factory at Eskilstuna. In his spare time he attended the Eskilstuna Technical College and in 1888 he was accepted as an apprentice armourer inspector. After completion of his apprenticeship he was appointed an armourer inspector, and it was in his work of inspection that he realized that the large number of gauges then required could be reduced if several accurate gauges could be used in combination. This was in 1896, and the first set of gauges was made for use in the rifle factory. With these, any dimension between 1 mm and 201 mm could be made up to the nearest 0.01 mm, the gauges having flat polished surfaces that would adhere together by "wringing". Johansson obtained patents for the system from 1901, but it was not until c.1907 that the sets of gauges were marketed generally. Gauges were made in inch units for Britain and America—slightly different as the standards were not then identical. Johansson formed his own company to manufacture the gauges in 1910, but he did not give up his post in the rifle factory until 1914. By the 1920s Johansson gauges were established as the engineering dimensional standards for the whole world; the company also made other precision measuring instruments such as micrometers and extensometers. A new company, C.E.Johansson Inc., was set up in America for manufacture and sales, and the gauges were extensively used in the American automobile industry. Henry Ford took a special interest and Johansson spent several years in a post with the Ford Motor Company in Detroit, Michigan, until he returned to Sweden in 1936.[br]Principal Honours and DistinctionsHonorary Doctorates, Gustavus Adolphus College, St Peter and Wayne University, Detroit. Swedish Engineering Society John Ericsson Gold Medal. American Society of Mechanical Engineers Gold Medal.Further ReadingK.J.Hume, 1980, A History of Engineering Metrology, London, pp. 54–66 (a short biography).RTS -
128 Kilby, Jack St Clair
SUBJECT AREA: Electronics and information technology[br]b. 8 November 1923 Jefferson City, Missouri, USA[br]American engineer who filed the first patents for micro-electronic (integrated) circuits.[br]Kilby spent most of his childhood in Great Bend, Kansas, where he often accompanied his father, an electrical power engineer, on his maintenance rounds. Working in the blizzard of 1937, his father borrowed a "ham" radio, and this fired Jack to study for his amateur licence (W9GTY) and to construct his own equipment while still a student at Great Bend High School. In 1941 he entered the University of Illinois, but four months later, after the attack on Pearl Harbor, he was enlisted in the US Army and found himself working in a radio repair workshop in India. When the war ended he returned to his studies, obtaining his BSEE from Illinois in 1947 and his MSEE from the University of Wisconsin. He then joined Centralab, a small electronics firm in Milwaukee owned by Globe-Union. There he filed twelve patents, including some for reduced titanate capacitors and for Steatite-packing of transistors, and developed a transistorized hearing-aid. During this period he also attended a course on transistors at Bell Laboratories. In May 1958, concerned to gain experience in the field of number processing, he joined Texas Instruments in Dallas. Shortly afterwards, while working alone during the factory vacation, he conceived the idea of making monolithic, or integrated, circuits by diffusing impurities into a silicon substrate to create P-N junctions. Within less than a month he had produced a complete oscillator on a chip to prove that the technology was feasible, and the following year at the 1ERE Show he demonstrated a germanium integrated-circuit flip-flop. Initially he was granted a patent for the idea, but eventually, after protracted litigation, priority was awarded to Robert Noyce of Fairchild. In 1965 he was commissioned by Patrick Haggerty, the Chief Executive of Texas Instruments, to make a pocket calculator based on integrated circuits, and on 14 April 1971 the world's first such device, the Pocketronic, was launched onto the market. Costing $150 (and weighing some 2½ lb or 1.1 kg), it was an instant success and in 1972 some 5 million calculators were sold worldwide. He left Texas Instruments in November 1970 to become an independent consultant and inventor, working on, amongst other things, methods of deriving electricity from sunlight.[br]Principal Honours and DistinctionsFranklin Institute Stuart Ballantine Medal 1966. Institute of Electrical and Electronics Engineers David Sarnoff Award 1966; Cledo Brunetti Award (jointly with Noyce) 1978; Medal of Honour 1986. National Academy of Engineering 1967. National Science Medal 1969. National Inventors Hall of Fame 1982. Honorary DEng Miami 1982, Rochester 1986. Honorary DSc Wisconsin 1988. Distinguished Professor, Texas A \& M University.Bibliography6 February 1959, US patent no. 3,138,743 (the first integrated circuit (IC); initially granted June 1964).US patent no. 3,819,921 (the Pocketronic calculator).Further ReadingT.R.Reid, 1984, Microchip. The Story of a Revolution and the Men Who Made It, London: Pan Books (for the background to the development of the integrated circuit). H.Queisser, 1988, Conquest of the Microchip, Cambridge, Mass.: Harvard University Press.KF
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