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121 Whitworth, Sir Joseph
[br]b. 21 December 1803 Stockport, Cheshire, Englandd. 22 January 1887 Monte Carlo, Monaco[br]English mechanical engineer and pioneer of precision measurement.[br]Joseph Whitworth received his early education in a school kept by his father, but from the age of 12 he attended a school near Leeds. At 14 he joined his uncle's mill near Ambergate, Derbyshire, to learn the business of cotton spinning. In the four years he spent there he realized that he was more interested in the machinery than in managing a cotton mill. In 1821 he obtained employment as a mechanic with Crighton \& Co., Manchester. In 1825 he moved to London and worked for Henry Maudslay and later for the Holtzapffels and Joseph Clement. After these years spent gaining experience, he returned to Manchester in 1833 and set up in a small workshop under a sign "Joseph Whitworth, Tool Maker, from London".The business expanded steadily and the firm made machine tools of all types and other engineering products including steam engines. From 1834 Whitworth obtained many patents in the fields of machine tools, textile and knitting machinery and road-sweeping machines. By 1851 the company was generally regarded as the leading manufacturer of machine tools in the country. Whitworth was a pioneer of precise measurement and demonstrated the fundamental mode of producing a true plane by making surface plates in sets of three. He advocated the use of the decimal system and made use of limit gauges, and he established a standard screw thread which was adopted as the national standard. In 1853 Whitworth visited America as a member of a Royal Commission and reported on American industry. At the time of the Crimean War in 1854 he was asked to provide machinery for manufacturing rifles and this led him to design an improved rifle of his own. Although tests in 1857 showed this to be much superior to all others, it was not adopted by the War Office. Whitworth's experiments with small arms led on to the construction of big guns and projectiles. To improve the quality of the steel used for these guns, he subjected the molten metal to pressure during its solidification, this fluid-compressed steel being then known as "Whitworth steel".In 1868 Whitworth established thirty annual scholarships for engineering students. After his death his executors permanently endowed the Whitworth Scholarships and distributed his estate of nearly half a million pounds to various educational and charitable institutions. Whitworth was elected an Associate of the Institution of Civil Engineers in 1841 and a Member in 1848 and served on its Council for many years. He was elected a Member of the Institution of Mechanical Engineers in 1847, the year of its foundation.[br]Principal Honours and DistinctionsBaronet 1869. FRS 1857. President, Institution of Mechanical Engineers 1856, 1857 and 1866. Hon. LLD Trinity College, Dublin, 1863. Hon. DCL Oxford University 1868. Member of the Smeatonian Society of Civil Engineers 1864. Légion d'honneur 1868. Society of Arts Albert Medal 1868.Bibliography1858, Miscellaneous Papers on Mechanical Subjects, London; 1873, Miscellaneous Papers on Practical Subjects: Guns and Steel, London (both are collections of his papers to technical societies).1854, with G.Wallis, The Industry of the United States in Machinery, Manufactures, andUseful and Ornamental Arts, London.Further ReadingF.C.Lea, 1946, A Pioneer of Mechanical Engineering: Sir Joseph Whitworth, London (a short biographical account).A.E.Musson, 1963, "Joseph Whitworth: toolmaker and manufacturer", Engineering Heritage, Vol. 1, London, 124–9 (a short biography).D.J.Jeremy (ed.), 1984–6, Dictionary of Business Biography, Vol. 5, London, 797–802 (a short biography).W.Steeds, 1969, A History of Machine Tools 1700–1910, Oxford (describes Whitworth's machine tools).RTS -
122 Wöhler, August
SUBJECT AREA: Metallurgy[br]b. 22 June 1819 Soltau, Germanyd. 21 June 1914 Hannover, Germany[br]German railway engineer who first established the fatigue fracture of metals.[br]Wöhler, the son of a schoolteacher, was born at Soltau on the Luneburg Heath and received his early education at his father's school, where his mathematical abilities soon became apparent. He completed his studies at the Technical High School, Hannover.In 1840 he obtained a position at the Borsig Engineering Works in Berlin and acquired there much valuable experience in railway technology. He trained as an engine driver in Belgium and in 1843 was appointed as an engineer to the first Hannoverian Railway, then being constructed between Hannover and Lehrte. In 1847 he became Chief Superintendent of rolling stock on the Lower Silesian-Brandenhurg Railway, where his technical abilities influenced the Prussian Minister of Commerce to appoint him to a commission set up to investigate the reasons for the unusually high incidence of axle failures then being encountered on the railways. This was in 1852, and by 1854, when the Brandenburg line had been nationalized, Wöhler had already embarked on the long, systematic programme of mechanical testing which eventually provided him with a clear insight into the process of what is now referred to as "fatigue failure". He concentrated initially on the behaviour of machined iron and steel specimens subjected to fluctuating direct, bending and torsional stresses that were imposed by testing machines of his own design.Although Wöhler was not the first investigator in this area, he was the first to recognize the state of "fatigue" induced in metals by the repeated application of cycles of stress at levels well below those that would cause immediate failure. His method of plotting the fatigue stress amplitude "S" against the number of stress cycles necessary to cause failure "N" yielded the well-known S-N curve which described very precisely the susceptibility to fatigue failure of the material concerned. Engineers were thus provided with an invaluable testing technique that is still widely used in the 1990s.Between 1851 and 1898 Wöhler published forty-two papers in German technical journals, although the importance of his work was not initially fully appreciated in other countries. A display of some of his fracture fatigue specimens at the Paris Exposition in 1867, however, stimulated a short review of his work in Engineering in London. Four years later, in 1871, Engineering published a series of nine articles which described Wöhler's findings in considerable detail and brought them to the attention of engineers. Wöhler became a member of the newly created management board of the Imperial German Railways in 1874, an appointment that he retained until 1889. He is also remembered for his derivation in 1855 of a formula for calculating the deflections under load of lattice girders, plate girders, and other continuous beams resting on more than two supports. This "Three Moments" theorem appeared two years before Clapeyron independently advanced the same expression. Wöhler's other major contribution to bridge design was to use rollers at one end to allow for thermal expansion and contraction.[br]Bibliography1855, "Theorie rechteckiger eiserner Brückenbalken", Zeitschrift für Bauwesen 5:122–66. 1870, "Über die Festigkeitversuche mit Eisen und Stahl", Zeitschrift für Bauwesen 20:73– 106.Wöhler's experiments on the fatigue of metals were reported in Engineering (1867) 2:160; (1871) 11:199–200, 222, 243–4, 261, 299–300, 326–7, 349–50, 397, 439–41.Further ReadingR.Blaum, 1918, "August Wöhler", Beiträge zur Geschichte der Technik und Industrie 8:35–55.——1925, "August Wöhler", Deutsches biographisches Jahrbuch, Vol. I, Stuttgart, pp. 103–7.K.Pearson, 1890, "On Wöhler's experiments on alternating stress", Messeng. Math.20:21–37.J.Gilchrist, 1900, "On Wöhler's Laws", Engineer 90:203–4.ASD -
123 Wozniak, Stephen G.
SUBJECT AREA: Electronics and information technology[br]b. 1950 Sunnyvale, California, USA[br]American computer engineer who with Steven Jobs built the first home computer.[br]Bored by school at Sunnyvale, the young Wozniak became interested in computers and at the age of only 13 years he constructed a transistorized calculator that won a prize at the Bay Area Science Fair. After high school, he went to the University of Colorado, but he left the following year to study at the De Anza College in Cupertino, California, finally dropping out of formal education altogether and working as a programmer for a small computer company. In 1971 he made another attempt at studying for a degree in engineering, this time at the University of California at Berkeley, but he again dropped out and went to work for Hewlett-Packard, where he met 16-year-old Steve Jobs. Joining the Homebrew Computer Club, and with Jobs's help, he built a home computer based on the MOS Technology 8-bit, 6502 microprocessor chip. With 4 K of random access memory (RAM) and the first BASIC interpreter written by Wozniak himself, he demonstrated the computer to Hewlett-Packard management, but they showed little interest in taking it up. With Jobs he therefore founded Apple Company, and with assembly in Jobs's home they found an interested buyer in the shape of Paul Terrill, owner of the newly established Byte Shop chain store, who ordered 100 boards at US$500 each. As a result, with the support of a backer, Mike Markkula, Wozniak in 1976 designed a second computer, the Apple II, which had 16 K of RAM and was offered for sale (without a monitor) at $1195. This was an immediate success and sales rose from $775,000 in 1977 to $335 million in 1981 and $983 million in 1983. In the meantime, however, Wozniak was seriously injured in a plane crash in 1980. He recovered slowly from his injuries and in 1982 returned to college to complete his degree course, after which he spent much of his time with his family. Eventually he became increasingly unhappy with the chaotic management at Apple, and he left the company in 1985, subsequently forming his own computer company, Cloud 9.[br]Principal Honours and DistinctionsFirst National Technology Medal (with Jobs) 1985.Further ReadingM.Moritz, 1984, The Little Kingdom. The Private Story of Apple Computers.J.S.Young, 1988, Steve Jobs: The Journey is the Reward: Scott Foreman \& Co.KF -
124 Yagi, Hidetsugu
[br]b. 28 January 1886 Osaka, Japand. January 1976 Osaka, Japan[br]Japanese engineer who, with his student Shintaro Uda, developed the directional ultra-high frequency (UHF) aerial array that bears his name.[br]Yagi studied engineering at Tokyo Imperial University (now Tokyo University), graduating in 1910. For the next four years he taught at Engineering High School in Sendai, Honshu, then in 1914 he was sent to study resonance phenomena under Barkhausen at Dresden University. When the First World War broke out he was touring Europe, so he travelled to London to study under Ambrose Fleming at University College, London. Continuing his travels, he then visited the USA, studying at Harvard under G.W. Pierce, before returning to his teaching post at Sendai Engineering High School, which in 1919 was absorbed into Tohoku University. There, in 1921, he obtained his doctorate, and some years later he was appointed Professor of Electrical Engineering. Having heard of the invention of the magnetron, he worked with a student, Kinjiro Okabe; in 1927 they produced microwave energy at a wavelength of a few tens of centimetres. However, he is best known for his development with another student, Shintaro Uda, of a directional, multi-element ultrahigh frequency aerial, which he demonstrated during a tour of the USA in 1928. During the Second World War Yagi worked on radar systems. After his retirement he became Professor Emeritus at Tohoku and Osaka universities and formed the Yagi Antenna Company.[br]Principal Honours and DistinctionsYagi received various honours, including the Japanese Cultural Order of Merit 1976, and the Valdemar Poulsen Gold Medal.Bibliography1928, "Beam transmission of ultra-short waves", Proceedings of the Institute of Radio Engineers 6:715 (describes the Yagi-Uda aerial).Further ReadingF.E.Terman, 1943, Radio Engineers' Handbook, New York: McGraw-Hill (provides a review of aerials, including the Yagi system).KF -
125 Achard, Franz
SUBJECT AREA: Agricultural and food technology[br]b. 1753 Germanyd. 1821 Germany[br]German scientist of French descent who built the world's first factory to extract sugar from beet.[br]The descendant of a French refugee, Achard began the systematic study of beet on his estate at Caulsdorf in 1786. The work had been stimulated by the discovery in 1747 of the presence of sugar in fodder beet. This research had been carried out by Andreas Marggraf, under whom Franz Achard trained. After a fire destroyed his laboratories Achard established himself on the domain of Französisch in Buchholtz near Berlin.After thirteen years of study he felt sufficiently confident to apply for an interview with Frederick William III, King of Prussia, which took place on 11 January 1799. Achard presented the King with a loaf of sugar made from raw beet by his Sugar Boiling House method. He requested a ten-year monopoly on his idea, as well as the grant of land on which to carry out his work. The King was sufficiently impressed to establish a committee to supervise further trials, and asked Achard to make a public statement on his work. The King ordered a factory to be built at his own expense, and paid Achard a salary to manage it. In 1801 he was granted the domain of Cunern in Silesia; he built his first sugar factory there and began production in 1802. Unfortunately Achard's business skills were negligible, and he was bankrupt within the year. In 1810 the State relieved him of his debt and gave him a pension, and in 1812 the first sugar factory was turned into a school of sugar technology.[br]BibliographyAchard's public response to the King's request was his paper Abhandlungen über die Kultur der Runkelrube.Further ReadingNoel Deerr, 1950, The History of Sugar, Vol. II, London (deals with the development of sugar extraction from beet, and therefore the story of both Marggraf and Achard).AP -
126 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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127 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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128 Appleby, John F.
SUBJECT AREA: Agricultural and food technology[br]b. 1840 New York, US Ad. ? USA[br]American inventor of the knotting mechanism used on early binders and still found on modern baling machines.[br]As a young man John Appleby worked as a labourer for a farmer near Whitewater in Wisconsin. He was 18 when the farmer bought a new reaping machine. Appleby believed that the concept had not been progressed far enough and that the machine should be able to bind sheaths as well as to cut the corn. It is claimed that while watching a dog playing with a skipping rope he noticed a particular knot created as the dog removed its head from the loop that had passed over it, and recognized the potential of the way in which this knot had been formed. From a piece of apple wood he carved a device that would produce the knot he had seen. A local school teacher backed Appleby's idea with a $50 loan, but the American Civil War and service in the Union Army prevented any further development until 1869 when he took out a patent on a wire-tying binder. A number of the devices were made for him by a company in Beloit. Trials of wire binders held in 1873 highlighted the danger of small pieces of wire caught up in the hay leading to livestock losses. Appleby looked again at the possibility of twine. In 1875 he successfully operated a machine and the following season four were in operation. A number of other developments, not least Behel's "bill hook" knotting device, were also to have an influence in the final development of Appleby's twine-tying binder. As so often happens, it was the vision of the entrepreneur which ultimately led to the success of Appleby's device. In 1877 Appleby persuaded William Deering to produce and market his binder, and 3,000 twine binders, together with the twine produced for them, were put on the market in 1880, with immediate success. Over the next dozen years all harvesting-machine manufacturers adopted the idea, under licence to Appleby.[br]Further ReadingG.Quick and W.Buchele, 1978, The Grain Harvesters, American Society of Agricultural Engineers (provides an account of the development of harvesting machinery and the various tying devices developed for them).1927, "Twine knotter history", Wisconsin Magazine of History (a more specific account).AP
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