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101 Brown, Samuel
SUBJECT AREA: Steam and internal combustion engines[br]b. unknownd. 1849 England[br]English cooper, inventor of a gas vacuum engine.[br]Between the years 1823 and 1833, Brown achieved a number of a firsts as a pioneer of internal-combustion engines. In 1824 he built a full-scale working model of a pumping engine; in 1826, a vehicle fitted with a gas vacuum engine ascended Shooters Hill in Kent; and in 1827 he conducted trials of a motor-driven boat on the Thames that were witnessed by Lords of the Admiralty. The principle of Brown's engine had been demonstrated by Cecil in 1820. A burning gas flame was extinguished within a closed cylinder, creating a partial vacuum; atmospheric pressure was then utilized to produce the working stroke. By 1832 a number of Brown's engines in use for pumping water were reported, the most notable being at Croydon Canal. However, high fuel consumption and running costs prevented a wide acceptance of Brown's engines, and a company formed in 1825 was dissolved only two years later. Brown continued alone with his work until his death.[br]Bibliography1823, British patent no. 4,874 (gas vacuum engine).1826, British patent no. 5,350 (improved gas vacuum engine).1846, British patent no. 11,076, "Improvements in Gas Engines and in Propelling Carriages and Vessels" (no specification was enrolled).Further ReadingVarious discussions of Brown's engines can be found in Mechanics Magazine (1824) 2:360, 385; (1825) 3:6; (1825) 4:19, 309; (1826) 5:145; (1826) 6:79; (1827) 7:82–134; (1832) 17:273.The Engineer 182:214.A.K.Bruce, Samuel Brown and the Gas Engine.Dugald Clerk, 1895, The Gas and Oil Engine, 6th edn, London, pp. 2–3.KAB -
102 Carnot, Nicolas Léonard Sadi
SUBJECT AREA: Steam and internal combustion engines[br]b. 1 June 1796 Paris, Franced. 24 August 1831 Paris, France[br]French laid the foundations for modern thermodynamics through his book Réflexions sur la puissance motrice du feu when he stated that the efficiency of an engine depended on the working substance and the temperature drop between the incoming and outgoing steam.[br]Sadi was the eldest son of Lazare Carnot, who was prominent as one of Napoleon's military and civil advisers. Sadi was born in the Palais du Petit Luxembourg and grew up during the Napoleonic wars. He was tutored by his father until in 1812, at the minimum age of 16, he entered the Ecole Polytechnique to study stress analysis, mechanics, descriptive geometry and chemistry. He organized the students to fight against the allies at Vincennes in 1814. He left the Polytechnique that October and went to the Ecole du Génie at Metz as a student second lieutenant. While there, he wrote several scientific papers, but on the Restoration in 1815 he was regarded with suspicion because of the support his father had given Napoleon. In 1816, on completion of his studies, Sadi became a second lieutenant in the Metz engineering regiment and spent his time in garrison duty, drawing up plans of fortifications. He seized the chance to escape from this dull routine in 1819 through an appointment to the army general staff corps in Paris, where he took leave of absence on half pay and began further courses of study at the Sorbonne, Collège de France, Ecole des Mines and the Conservatoire des Arts et Métiers. He was inter-ested in industrial development, political economy, tax reform and the fine arts.It was not until 1821 that he began to concentrate on the steam-engine, and he soon proposed his early form of the Carnot cycle. He sought to find a general solution to cover all types of steam-engine, and reduced their operation to three basic stages: an isothermal expansion as the steam entered the cylinder; an adiabatic expansion; and an isothermal compression in the condenser. In 1824 he published his Réflexions sur la puissance motrice du feu, which was well received at the time but quickly forgotten. In it he accepted the caloric theory of heat but pointed out the impossibility of perpetual motion. His main contribution to a correct understanding of a heat engine, however, lay in his suggestion that power can be produced only where there exists a temperature difference due "not to an actual consumption of caloric but to its transportation from a warm body to a cold body". He used the analogy of a water-wheel with the water falling around its circumference. He proposed the true Carnot cycle with the addition of a final adiabatic compression in which motive power was con sumed to heat the gas to its original incoming temperature and so closed the cycle. He realized the importance of beginning with the temperature of the fire and not the steam in the boiler. These ideas were not taken up in the study of thermodynartiics until after Sadi's death when B.P.E.Clapeyron discovered his book in 1834.In 1824 Sadi was recalled to military service as a staff captain, but he resigned in 1828 to devote his time to physics and economics. He continued his work on steam-engines and began to develop a kinetic theory of heat. In 1831 he was investigating the physical properties of gases and vapours, especially the relationship between temperature and pressure. In June 1832 he contracted scarlet fever, which was followed by "brain fever". He made a partial recovery, but that August he fell victim to a cholera epidemic to which he quickly succumbed.[br]Bibliography1824, Réflexions sur la puissance motrice du feu; pub. 1960, trans. R.H.Thurston, New York: Dover Publications; pub. 1978, trans. Robert Fox, Paris (full biographical accounts are provided in the introductions of the translated editions).Further ReadingDictionary of Scientific Biography, 1971, Vol. III, New York: C.Scribner's Sons. T.I.Williams (ed.), 1969, A Biographical Dictionary of Scientists, London: A. \& C.Black.Chambers Concise Dictionary of Scientists, 1989, Cambridge.D.S.L.Cardwell, 1971, from Watt to Clausius. The Rise of Thermodynamics in the Early Industrial Age, London: Heinemann (discusses Carnot's theories of heat).RLHBiographical history of technology > Carnot, Nicolas Léonard Sadi
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103 Gresley, Sir Herbert Nigel
[br]b. 19 June 1876 Edinburgh, Scotlandd. 5 April 1941 Hertford, England[br]English mechanical engineer, designer of the A4-class 4–6–2 locomotive holding the world speed record for steam traction.[br]Gresley was the son of the Rector of Netherseale, Derbyshire; he was educated at Marlborough and by the age of 13 was skilled at making sketches of locomotives. In 1893 he became a pupil of F.W. Webb at Crewe works, London \& North Western Railway, and in 1898 he moved to Horwich works, Lancashire \& Yorkshire Railway, to gain drawing-office experience under J.A.F.Aspinall, subsequently becoming Foreman of the locomotive running sheds at Blackpool. In 1900 he transferred to the carriage and wagon department, and in 1904 he had risen to become its Assistant Superintendent. In 1905 he moved to the Great Northern Railway, becoming Superintendent of its carriage and wagon department at Doncaster under H.A. Ivatt. In 1906 he designed and produced a bogie luggage van with steel underframe, teak body, elliptical roof, bowed ends and buckeye couplings: this became the prototype for East Coast main-line coaches built over the next thirty-five years. In 1911 Gresley succeeded Ivatt as Locomotive, Carriage \& Wagon Superintendent. His first locomotive was a mixed-traffic 2–6–0, his next a 2–8–0 for freight. From 1915 he worked on the design of a 4–6–2 locomotive for express passenger traffic: as with Ivatt's 4 4 2s, the trailing axle would allow the wide firebox needed for Yorkshire coal. He also devised a means by which two sets of valve gear could operate the valves on a three-cylinder locomotive and applied it for the first time on a 2–8–0 built in 1918. The system was complex, but a later simplified form was used on all subsequent Gresley three-cylinder locomotives, including his first 4–6–2 which appeared in 1922. In 1921, Gresley introduced the first British restaurant car with electric cooking facilities.With the grouping of 1923, the Great Northern Railway was absorbed into the London \& North Eastern Railway and Gresley was appointed Chief Mechanical Engineer. More 4–6– 2s were built, the first British class of such wheel arrangement. Modifications to their valve gear, along lines developed by G.J. Churchward, reduced their coal consumption sufficiently to enable them to run non-stop between London and Edinburgh. So that enginemen might change over en route, some of the locomotives were equipped with corridor tenders from 1928. The design was steadily improved in detail, and by comparison an experimental 4–6–4 with a watertube boiler that Gresley produced in 1929 showed no overall benefit. A successful high-powered 2–8–2 was built in 1934, following the introduction of third-class sleeping cars, to haul 500-ton passenger trains between Edinburgh and Aberdeen.In 1932 the need to meet increasing road competition had resulted in the end of a long-standing agreement between East Coast and West Coast railways, that train journeys between London and Edinburgh by either route should be scheduled to take 8 1/4 hours. Seeking to accelerate train services, Gresley studied high-speed, diesel-electric railcars in Germany and petrol-electric railcars in France. He considered them for the London \& North Eastern Railway, but a test run by a train hauled by one of his 4–6–2s in 1934, which reached 108 mph (174 km/h), suggested that a steam train could better the railcar proposals while its accommodation would be more comfortable. To celebrate the Silver Jubilee of King George V, a high-speed, streamlined train between London and Newcastle upon Tyne was proposed, the first such train in Britain. An improved 4–6–2, the A4 class, was designed with modifications to ensure free running and an ample reserve of power up hill. Its streamlined outline included a wedge-shaped front which reduced wind resistance and helped to lift the exhaust dear of the cab windows at speed. The first locomotive of the class, named Silver Link, ran at an average speed of 100 mph (161 km/h) for 43 miles (69 km), with a maximum speed of 112 1/2 mph (181 km/h), on a seven-coach test train on 27 September 1935: the locomotive went into service hauling the Silver Jubilee express single-handed (since others of the class had still to be completed) for the first three weeks, a round trip of 536 miles (863 km) daily, much of it at 90 mph (145 km/h), without any mechanical troubles at all. Coaches for the Silver Jubilee had teak-framed, steel-panelled bodies on all-steel, welded underframes; windows were double glazed; and there was a pressure ventilation/heating system. Comparable trains were introduced between London Kings Cross and Edinburgh in 1937 and to Leeds in 1938.Gresley did not hesitate to incorporate outstanding features from elsewhere into his locomotive designs and was well aware of the work of André Chapelon in France. Four A4s built in 1938 were equipped with Kylchap twin blast-pipes and double chimneys to improve performance still further. The first of these to be completed, no. 4468, Mallard, on 3 July 1938 ran a test train at over 120 mph (193 km/h) for 2 miles (3.2 km) and momentarily achieved 126 mph (203 km/h), the world speed record for steam traction. J.Duddington was the driver and T.Bray the fireman. The use of high-speed trains came to an end with the Second World War. The A4s were then demonstrated to be powerful as well as fast: one was noted hauling a 730-ton, 22-coach train at an average speed exceeding 75 mph (120 km/h) over 30 miles (48 km). The war also halted electrification of the Manchester-Sheffield line, on the 1,500 volt DC overhead system; however, anticipating eventual resumption, Gresley had a prototype main-line Bo-Bo electric locomotive built in 1941. Sadly, Gresley died from a heart attack while still in office.[br]Principal Honours and DistinctionsKnighted 1936. President, Institution of Locomotive Engineers 1927 and 1934. President, Institution of Mechanical Engineers 1936.Further ReadingF.A.S.Brown, 1961, Nigel Gresley, Locomotive Engineer, Ian Allan (full-length biography).John Bellwood and David Jenkinson, Gresley and Stanier. A Centenary Tribute (a good comparative account).See also: Bulleid, Oliver Vaughan SnellPJGRBiographical history of technology > Gresley, Sir Herbert Nigel
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104 Phillips, Horatio Frederick
SUBJECT AREA: Aerospace[br]b. 2 February 1845 London, Englandd. 15 July 1926 Hampshire, England[br]English aerodynamicist whose cambered two-surface wing sections provided the foundations for aerofoil design.[br]At the age of 19, Phillips developed an interest in flight and constructed models with lightweight engines. He spent a large amount of time and money over many years, carrying out practical research into the science of aerodynamics. In the early 1880s he built a wind tunnel with a working section of 15 in. by 10 in. (38 cm by 25 cm). Air was sucked through the working section by an adaptation of the steam injector used in boilers and invented by Henry Giffard, the airship pioneer. Phillips tested aerofoils based on the cross-section of bird's wings, with a greater curvature on the upper surface than the lower. He measured the lift and drag and showed that the major component of lift came from suction on the upper surface, rather than pressure on the lower. He took out patents for his aerofoil sections in 1884 and 1891. In addition to his wind-tunnel test, Phillips tested his wing sections on a whirling arm, as used earlier by Cayley, Wenham and Lilienthal. After a series of tests using an arm of 15 ft (4.57 m) radius, Phillips built a massive whirling arm driven by a steam engine. His test pieces were mounted on the end of the arm, which had a radius of 50 ft (15.24 m), giving them a linear speed of 70 mph (113 km/h). By 1893 Phillips was ready to put his theories to a more practical test, so he built a large model aircraft driven by a steam engine and tethered to run round a circular track. It had a wing span of 19 ft (5.79 m), but it had fifty wings, one above the other. These wings were only 10 in. (25 cm) wide and mounted in a frame, so it looked rather like a Venetian blind. At 40 mph (64 km/h) it lifted off the track. In 1904 Phillips built a full-size multi-wing aeroplane with twenty wings which just lifted off the ground but did not fly. He built another multi-wing machine in 1907, this time with four Venetian blind' frames in tandem, giving it two hundred wings! Phillips made a short flight of almost 500 ft (152 m) which could be claimed to be the first powered aeroplane flight in England by an Englishman. He retired from flying at the age of 62.[br]Bibliography1900, "Mechanical flight and matters relating thereto", Engineering (reprint).1891–3, "On the sustentation of weight by mechanical flight", Aeronautical Society of Great Britain 23rd Report.Further ReadingJ.Laurence Pritchard, 1957, "The dawn of aerodynamics", Journal of the Royal Aeronautical Society (March) (good descriptions of Phillips's early work and his wind tunnel).J.E.Hodgson, 1924, The History of Aeronautics in Great Britain, London.F.W.Brearey, 1891–3, "Remarks on experiments made by Horatio Phillips", Aeronautical Society of Great Britain 23rd Report.JDSBiographical history of technology > Phillips, Horatio Frederick
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105 Wenham, Francis Herbert
SUBJECT AREA: Aerospace[br]b. 1824 London, Englandd. 11 August 1908 Folkestone, England[br]English engineer, inventor and pioneer aerodynamicist who built the first wind tunnel.[br]Wenham trained as a marine engineer and later specialized in screw propellers and high-pressure engines. He had many interests. He took his steamboat to the Nile and assisted the photographer F.Frith to photograph Egyptian tombs by devising a series of mirrors to deflect sunlight into the dark recesses. He experimented with gas engines and produced a hot-air engine. Wenham was a leading, if controversial, figure in the Microscopical Society and a member of the Royal Photographic Society; he developed an enlarger.Wenham was interested in both mechanical and lighter-than-air flight. One of his friends was James Glaisher, a well-known balloonist who made many ascents to gather scientific information. When the (Royal) Aeronautical Society of Great Britain was founded in 1866, the Rules were drawn up by Wenham, Glaisher and the Honorary Secretary, F.W.Brearey. At the first meeting of the Society, on 27 June 1866, "On aerial locomotion and the laws by which heavy bodies impelled through the air are sustained" was read by Wenham. In his paper Wenham described his experiments with a whirling arm (used earlier by Cayley) to measure lift and drag on flat surfaces inclined at various angles of incidence. His studies of birds' wings and, in particular, their wing loading, showed that they derived most of their lift from the front portion, hence a long, thin wing was better than a short, wide one. He published illustrations of his glider designs covering his experiments of c. 1858–9. One of these had five slender wings one above the other, an idea later developed by Horatio Phillips. Wenham had some success with a model, but no real success with his full-size gliders.In 1871, Wenham and John Browning constructed the first wind tunnel designed for aeronautical research. It utilized a fan driven by a steam engine to propel the air and had a working section of 18 in. (116 cm). Wenham continued to play an important role in aeronautical matters for many years, including a lengthy exchange of ideas with Octave Chanute from 1892 onwards.[br]Principal Honours and DistinctionsHonorary Member of the (Royal) Aeronautical Society.BibliographyWenham published many reports and papers. These are listed, together with a reprint of his paper "Aerial locomotion", in the Journal of the Royal Aeronautical Society (August 1958).Further ReadingTwo papers by J.Laurence Pritchard, 1957, "The dawn of aerodynamics" Journal of the Royal Aeronautical Society (March); 1958, "Francis Herbert Wenham", Journal of the Royal Aeronautical Society (August) (both papers describe Wenham and his work).J.E.Hodgson, 1924, History of Aeronautics in Great Britain, London.JDSBiographical history of technology > Wenham, Francis Herbert
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