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21 Bell, Alexander Graham
SUBJECT AREA: Telecommunications[br]b. 3 March 1847 Edinburgh, Scotlandd. 3 August 1922 Beinn Bhreagh, Baddeck, Cape Breton Island, Nova Scotia, Canada[br]Scottish/American inventor of the telephone.[br]Bell's grandfather was a professor of elocution in London and his father an authority on the physiology of the voice and on elocution; Bell was to follow in their footsteps. He was educated in Edinburgh, leaving school at 13. In 1863 he went to Elgin, Morayshire, as a pupil teacher in elocution, with a year's break to study at Edinburgh University; it was in 1865, while still in Elgin, that he first conceived the idea of the electrical transmission of speech. He went as a master to Somersetshire College, Bath (now in Avon), and in 1867 he moved to London to assist his father, who had taken up the grandfather's work in elocution. In the same year, he matriculated at London University, studying anatomy and physiology, and also began teaching the deaf. He continued to pursue the studies that were to lead to the invention of the telephone. At this time he read Helmholtz's The Sensations of Tone, an important work on the theory of sound that was to exert a considerable influence on him.In 1870 he accompanied his parents when they emigrated to Canada. His work for the deaf gained fame in both Canada and the USA, and in 1873 he was apponted professor of vocal physiology and the mechanics of speech at Boston University, Massachusetts. There, he continued to work on his theory that sound wave vibrations could be converted into a fluctuating electric current, be sent along a wire and then be converted back into sound waves by means of a receiver. He approached the problem from the background of the theory of sound and voice production rather than from that of electrical science, and by 1875 he had succeeded in constructing a rough model. On 7 March 1876 Bell spoke the famous command to his assistant, "Mr Watson, come here, I want you": this was the first time a human voice had been transmitted along a wire. Only three days earlier, Bell's first patent for the telephone had been granted. Almost simultaneously, but quite independently, Elisha Gray had achieved a similar result. After a period of litigation, the US Supreme Court awarded Bell priority, although Gray's device was technically superior.In 1877, three years after becoming a naturalized US citizen, Bell married the deaf daughter of his first backer. In August of that year, they travelled to Europe to combine a honeymoon with promotion of the telephone. Bell's patent was possibly the most valuable ever issued, for it gave birth to what later became the world's largest private service organization, the Bell Telephone Company.Bell had other scientific and technological interests: he made improvements in telegraphy and in Edison's gramophone, and he also developed a keen interest in aeronautics, working on Curtiss's flying machine. Bell founded the celebrated periodical Science.[br]Principal Honours and DistinctionsLegion of Honour; Hughes Medal, Royal Society, 1913.Further ReadingObituary, 7 August 1922, The Times. Dictionary of American Biography.R.Burlingame, 1964, Out of Silence into Sound, London: Macmillan.LRD -
22 Bouch, Sir Thomas
SUBJECT AREA: Civil engineering[br]b. 22 February 1822 Thursby, Cumberland, Englandd. 1880 Moffat[br]English designer of the ill-fated Tay railway bridge.[br]The third son of a merchant sea captain, he was at first educated in the village school. At the age of 17 he was working under a Mr Larmer, a civil engineer, constructing the Lancaster and Carlisle railway. He later moved to be a resident engineer on the Stockton \& Darlington Railway, and from 1849 was Engineer and Manager of the Edinburgh \& Northern Railway. In this last position he became aware of the great inconvenience caused to traffic by the broad estuaries of the Tay and the Forth on the eastern side of Scotland. The railway later became the Edinburgh, Perth \& Dundee, and was then absorbed into the North British in 1854 when Bouch produced his first plans for a bridge across the Tay at an estimated cost of £200,000. A bill was passed for the building of the bridge in 1870. Prior to this, Bouch had built many bridges up to the Redheugh Viaduct, at Newcastle upon Tyne, which had two spans of 240 ft (73 m) and two of 260 ft (79 m). He had also set up in business on his own. He is said to have designed nearly 300 miles (480 km) of railway in the north, as well as a "floating railway" of steam ferries to carry trains across the Forth and the Tay. The Tay bridge, however, was his favourite project; he had hawked it for some twenty years before getting the go-ahead, and the foundation stone of the bridge was laid on 22 July 1871. The total length of the bridge was nearly two miles (3.2 km), while the shore-to-shore distance over the river was just over one mile (1.6 km). It consisted of eighty-five spans, thirteen of which, i.e. "the high girders", were some 245 ft (75 m) long and 100 ft (30 m) above water level to allow for shipping access to Perth, and was a structure of lattice girders on brick and masonry piers topped with ironwork. The first crossing of the bridge was made on 26 September 1877, and the official opening was on 31 May 1878. On Sunday 28 December 1879, at about 7.20 pm, in a wind of probably 90 mph (145 km/h), the thirteen "high girders" were blown into the river below, drowning the seventy-five passengers and crew aboard the 5.20 train from Burntisland. A Court of Enquiry was held and revealed design faults in that the effect of wind pressure had not been adequately taken into account, faults in manufacture in the plugging of flaws in the castings, and inadequate inspection and maintenance; all of these faults were attributed to Bouch, who had been knighted for the building of the bridge. He died at his house in Moffat four months after the enquiry.[br]Principal Honours and DistinctionsKnighted. Cross of St George.Further ReadingJohn Prebble, 1956, The High Girders.IMcN -
23 Leschot, Georges Auguste
[br]b. 24 March 1800 Geneva, Switzerlandd. 4 February 1884 Geneva, Switzerland[br]Swiss clockmaker, inventor of diamond drilling.[br]By about 1843, Leschot, who was renowned for designing machines to produce parts of clocks on an industrialized scale, had gathered that the fine, deep lines he found on an Egyptian red porphyry plate must have been cut by diamonds. He thus resurrected a technology that had been largely forgotten over the centuries, when in 1862 his son, who was engaged in constructing a railway line in Italy, was confronted with the problems of tunnelling through hard rock. In Paris he developed a drilling machine consisting of a casing that rotated in a similar way to the American rope drilling method. The crown of the machine was mounted with eight black diamonds, and inside the casing a stream of water circulated continuously to flush out the mud.He took out his first patent in France in 1862, and followed it with further ones in many European countries and in America. He continued to concentrate on his watchmaker's profession and left the rights to his patents to his son. It was Leschot's ingenious idea of utilizing diamonds for drilling hard rock that was later applied in different mining processes. It influenced a series of further developments in many countries, including those of Alfred Brandt and Major Beaumont in England. In particular, the fact that the hollow casing produced a complete core was of importance for the increasing amount of petroleum prospecting in Pennsylvania after Edwin Laurentine Drake's find of 1859, where M.C.Bullock sunk the first deep well (200 m) in the world by diamond drilling in 1870. The efforts of Per Anton Crælius in Sweden made diamond drilling a success worldwide.[br]Further ReadingD.Colladon, 1884, "Notice sur les inventions mécaniques de M.G.Leschot, horloger", Archives des Sciences Physiques et Naturelles 3, XI (1):297–313 (discusses the influences of Leschot's invention on other engineers in Europe).D.Hoffmann, 1962, "Die Erfindung der Diamantbohrmaschine vor 100 Jahren", Der Anschnitt 14(1):15–19 (contains detailed biographical outlines).WKBiographical history of technology > Leschot, Georges Auguste
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24 Rowland, Thomas Fitch
SUBJECT AREA: Mining and extraction technology[br]b. 15 March 1831 New Haven, Connecticut, USAd. 13 December 1907 New York City, USA[br]American engineer and manufacturer, inventor of off-shore drilling.[br]The son of a grist miller, Rowland worked in various jobs until 1859 when he established his own business for the construction of wooden and iron steamships and for structural iron works, in Greenpoint, Long Island, New York. In 1860 he founded the Continental Works and during the American Civil War he started manufacturing gun carriages and mortar beds. He fitted out many vessels for the navy, and as a contractor for John Ericsson he built heavily armoured war vessels.He continued shipbuilding, but later diversified his business. He devoted great attention to the design of gas-works, constructing innovative storage facilities all over the United States, and he was concerned with the improvement of welding iron and steel plates and other processes in the steel industry. In the late 1860s he also began the manufacture of steam-engines and boilers for use in the new but expanding oil industry. In 1869 he took out a patent for a fixed platform for drilling for oil off-shore up to a depth of 15 m (49 ft). With this idea, just ten years after Edwin Drake's success in on-shore oil drilling in Titusville, Pennsylvania, Rowland pioneered the technology of off-shore drilling for petroleum in which the United States later became the leading nation.[br]Principal Honours and DistinctionsAmerican Society of Civil Engineers: Director 1871–3, Vice-President 1886–7, Honorary Member 1899.Further Reading"Thomas Fitch Rowland", Dictionary of American Biography.1909, "Memoir", Transactions of the American Society of Civil Engineers 62:547–9.WK -
25 Smith, Sir Francis Pettit
SUBJECT AREA: Ports and shipping[br]b. 9 February 1808 Copperhurst Farm, near Hythe, Kent, Englandd. 12 February 1874 South Kensington, London, England[br]English inventor of the screw propeller.[br]Smith was the only son of Charles Smith, Postmaster at Hythe, and his wife Sarah (née Pettit). After education at a private school in Ashford, Kent, he took to farming, first on Romney Marsh, then at Hendon, Middlesex. As a boy, he showed much skill in the construction of model boats, especially in devising their means of propulsion. He maintained this interest into adult life and in 1835 he made a model propelled by a screw driven by a spring. This worked so well that he became convinced that the screw propeller offered a better method of propulsion than the paddle wheels that were then in general use. This notion so fired his enthusiasm that he virtually gave up farming to devote himself to perfecting his invention. The following year he produced a better model, which he successfully demonstrated to friends on his farm at Hendon and afterwards to the public at the Adelaide Gallery in London. On 31 May 1836 Smith was granted a patent for the propulsion of vessels by means of a screw.The idea of screw propulsion was not new, however, for it had been mooted as early as the seventeenth century and since then several proposals had been advanced, but without successful practical application. Indeed, simultaneously but quite independently of Smith, the Swedish engineer John Ericsson had invented the ship's propeller and obtained a patent on 13 July 1836, just weeks after Smith. But Smith was completely unaware of this and pursued his own device in the belief that he was the sole inventor.With some financial and technical backing, Smith was able to construct a 10 ton boat driven by a screw and powered by a steam engine of about 6 hp (4.5 kW). After showing it off to the public, Smith tried it out at sea, from Ramsgate round to Dover and Hythe, returning in stormy weather. The screw performed well in both calm and rough water. The engineering world seemed opposed to the new method of propulsion, but the Admiralty gave cautious encouragement in 1839 by ordering that the 237 ton Archimedes be equipped with a screw. It showed itself superior to the Vulcan, one of the fastest paddle-driven ships in the Navy. The ship was put through its paces in several ports, including Bristol, where Isambard Kingdom Brunel was constructing his Great Britain, the first large iron ocean-going vessel. Brunel was so impressed that he adapted his ship for screw propulsion.Meanwhile, in spite of favourable reports, the Admiralty were dragging their feet and ordered further trials, fitting Smith's four-bladed propeller to the Rattler, then under construction and completed in 1844. The trials were a complete success and propelled their lordships of the Admiralty to a decision to equip twenty ships with screw propulsion, under Smith's supervision.At last the superiority of screw propulsion was generally accepted and virtually universally adopted. Yet Smith gained little financial reward for his invention and in 1850 he retired to Guernsey to resume his farming life. In 1860 financial pressures compelled him to accept the position of Curator of Patent Models at the Patent Museum in South Kensington, London, a post he held until his death. Belated recognition by the Government, then headed by Lord Palmerston, came in 1855 with the grant of an annual pension of £200. Two years later Smith received unofficial recognition when he was presented with a national testimonial, consisting of a service of plate and nearly £3,000 in cash subscribed largely by the shipbuilding and engineering community. Finally, in 1871 Smith was honoured with a knighthood.[br]Principal Honours and DistinctionsKnighted 1871.Further ReadingObituary, 1874, Illustrated London News (7 February).1856, On the Invention and Progress of the Screw Propeller, London (provides biographical details).Smith and his invention are referred to in papers in Transactions of the Newcomen Society, 14 (1934): 9; 19 (1939): 145–8, 155–7, 161–4, 237–9.LRDBiographical history of technology > Smith, Sir Francis Pettit
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26 Tesla, Nikola
SUBJECT AREA: Electricity[br]b. 9 July 1856 Smiljan, Croatiad. 7 January 1943 New York, USA[br]Serbian (naturalized American) engineer and inventor of polyphase electrical power systems.[br]While at the technical institute in Graz, Austria, Tesla's attention was drawn to the desirability of constructing a motor without a commutator. He considered the sparking between the commutator and brushes of the Gramme machine when run as a motor a serious defect. In 1881 he went to Budapest to work on the telegraph system and while there conceived the principle of the rotating magnetic field, upon which all polyphase induction motors are based. In 1882 Tesla moved to Paris and joined the Continental Edison Company. After building a prototype of his motor he emigrated to the United States in 1884, becoming an American citizen in 1889. He left Edison and founded an independent concern, the Tesla Electric Company, to develop his inventions.The importance of Tesla's first patents, granted in 1888 for alternating-current machines, cannot be over-emphasized. They covered a complete polyphase system including an alternator and induction motor. Other patents included the polyphase transformer, synchronous motor and the star connection of three-phase machines. These were to become the basis of the whole of the modern electric power industry. The Westinghouse company purchased the patents and marketed Tesla motors, obtaining in 1893 the contract for the Niagara Falls two-phase alternators driven by 5,000 hp (3,700 kW) water turbines.After a short period with Westinghouse, Tesla resigned to continue his research into high-frequency and high-voltage phenomena using the Tesla coil, an air-cored transformer. He lectured in America and Europe on his high-frequency devices, enjoying a considerable international reputation. The name "tesla" has been given to the SI unit of magnetic-flux density. The induction motor became one of the greatest advances in the industrial application of electricity. A claim for priority of invention of the induction motor was made by protagonists of Galileo Ferraris (1847–1897), whose discovery of rotating magnetic fields produced by alternating currents was made independently of Tesla's. Ferraris demonstrated the phenomenon but neglected its exploitation to produce a practical motor. Tesla himself failed to reap more than a small return on his work and later became more interested in scientific achievement than commercial success, with his patents being infringed on a wide scale.[br]Principal Honours and DistinctionsAmerican Institute of Electrical Engineers Edison Medal 1917. Tesla received doctorates from fourteen universities.Bibliography1 May 1888, American patent no. 381,968 (initial patent for the three-phase induction motor).1956, Nikola Tesla, 1856–1943, Lectures, Patents, Articles, ed. L.I.Anderson, Belgrade (selected works, in English).1977, My Inventions, repub. Zagreb (autobiography).Further ReadingM.Cheney, 1981, Tesla: Man Out of Time, New Jersey (a full biography). C.Mackechnie Jarvis, 1969, in IEE Electronics and Power 15:436–40 (a brief treatment).T.C.Martin, 1894, The Inventions, Researches and Writings of Nikola Tesla, New York (covers his early work on polyphase systems).GW -
27 Vignoles, Charles Blacker
[br]b. 31 May 1793 Woodbrook, Co. Wexford, Irelandd. 17 November 1875 Hythe, Hampshire, England[br]English surveyor and civil engineer, pioneer of railways.[br]Vignoles, who was of Huguenot descent, was orphaned in infancy and brought up in the family of his grandfather, Dr Charles Hutton FRS, Professor of Mathematics at the Royal Military Academy, Woolwich. After service in the Army he travelled to America, arriving in South Carolina in 1817. He was appointed Assistant to the state's Civil Engineer and surveyed much of South Carolina and subsequently Florida. After his return to England in 1823 he established himself as a civil engineer in London, and obtained work from the brothers George and John Rennie.In 1825 the promoters of the Liverpool \& Manchester Railway (L \& MR) lost their application for an Act of Parliament, discharged their engineer George Stephenson and appointed the Rennie brothers in his place. They in turn employed Vignoles to resurvey the railway, taking a route that would minimize objections. With Vignoles's route, the company obtained its Act in 1826 and appointed Vignoles to supervise the start of construction. After Stephenson was reappointed Chief Engineer, however, he and Vignoles proved incompatible, with the result that Vignoles left the L \& MR early in 1827.Nevertheless, Vignoles did not sever all connection with the L \& MR. He supported John Braithwaite and John Ericsson in the construction of the locomotive Novelty and was present when it competed in the Rainhill Trials in 1829. He attended the opening of the L \& MR in 1830 and was appointed Engineer to two railways which connected with it, the St Helens \& Runcorn Gap and the Wigan Branch (later extended to Preston as the North Union); he supervised the construction of these.After the death of the Engineer to the Dublin \& Kingstown Railway, Vignoles supervised construction: the railway, the first in Ireland, was opened in 1834. He was subsequently employed in surveying and constructing many railways in the British Isles and on the European continent; these included the Eastern Counties, the Midland Counties, the Sheffield, Ashton-under-Lyme \& Manchester (which proved for him a financial disaster from which he took many years to recover), and the Waterford \& Limerick. He probably discussed rail of flat-bottom section with R.L. Stevens during the winter of 1830–1 and brought it into use in the UK for the first time in 1836 on the London \& Croydon Railway: subsequently rail of this section became known as "Vignoles rail". He considered that a broader gauge than 4 ft 8½ in. (1.44 m) was desirable for railways, although most of those he built were to this gauge so that they might connect with others. He supported the atmospheric system of propulsion during the 1840s and was instrumental in its early installation on the Dublin \& Kingstown Railway's Dalkey extension. Between 1847 and 1853 he designed and built the noted multi-span suspension bridge at Kiev, Russia, over the River Dnieper, which is more than half a mile (800 m) wide at that point.Between 1857 and 1863 he surveyed and then supervised the construction of the 155- mile (250 km) Tudela \& Bilbao Railway, which crosses the Cantabrian Pyrenees at an altitude of 2,163 ft (659 m) above sea level. Vignoles outlived his most famous contemporaries to become the grand old man of his profession.[br]Principal Honours and DistinctionsFellow of the Royal Astronomical Society 1829. FRS 1855. President, Institution of Civil Engineers 1869–70.Bibliography1830, jointly with John Ericsson, British patent no. 5,995 (a device to increase the capability of steam locomotives on grades, in which rollers gripped a third rail).1823, Observations upon the Floridas, New York: Bliss \& White.1870, Address on His Election as President of the Institution of Civil Engineers.Further ReadingK.H.Vignoles, 1982, Charles Blacker Vignoles: Romantic Engineer, Cambridge: Cambridge University Press (good modern biography by his great-grandson).See also: Samuda, Joseph d'AguilarPJGRBiographical history of technology > Vignoles, Charles Blacker
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28 Wyatt, John
[br]b. April 1700 Thickbroom, Weeford, near Lichfield, Englandd. 29 November 1766 Birmingham, England[br]English inventor of machines for making files and rolling lead, and co-constructor of a cotton-spinning machine.[br]John Wyatt was the eldest son of John and Jane Wyatt, who lived in the small village of Thickbroom in the parish of Weeford, near Lichfield. John the younger was educated at Lichfield school and then worked as a carpenter at Thickbroom till 1730. In 1732 he was in Birmingham, engaged by a man named Heely, a gunbarrel forger, who became bankrupt in 1734. Wyatt had invented a machine for making files and sought the help of Lewis Paul to manufacture this commercially.The surviving papers of Paul and Wyatt in Birmingham are mostly undated and show a variety of machines with which they were involved. There was a machine for "making lead hard" which had rollers, and "a Gymcrak of some consequence" probably refers to a machine for boring barrels or the file-making machine. Wyatt is said to have been one of the unsuccessful competitors for the erection of London Bridge in 1736. He invented and perfected the compound-lever weighing machine. He had more success with this: after 1744, machines for weighing up to five tons were set up at Birmingham, Chester, Gloucester, Hereford, Lichfield and Liverpool. Road construction, bridge building, hydrostatics, canals, water-powered engines and many other schemes received his attention and it is said that he was employed for a time after 1744 by Matthew Boulton.It is certain that in April 1735 Paul and Wyatt were working on their spinning machine and Wyatt was making a model of it in London in 1736, giving up his work in Birmingham. The first patent, in 1738, was taken out in the name of Lewis Paul. It is impossible to know which of these two invented what. This first patent covers a wide variety of descriptions of the vital roller drafting to draw out the fibres, and it is unknown which system was actually used. Paul's carding patent of 1748 and his second spinning patent of 1758 show that he moved away from the system and principles upon which Arkwright built his success. Wyatt and Paul's spinning machines were sufficiently promising for a mill to be set up in 1741 at the Upper Priory, Birmingham, that was powered by two asses. Wyatt was the person responsible for constructing the machinery. Edward Cave established another at Northampton powered by water while later Daniel Bourn built yet another at Leominster. Many others were interested too. The Birmingham mill did not work for long and seems to have been given up in 1743. Wyatt was imprisoned for debt in The Fleet in 1742, and when released in 1743 he tried for a time to run the Birmingham mill and possibly the Northampton one. The one at Leominster burned down in 1754, while the Northampton mill was advertised for sale in 1756. This last mill may have been used again in conjunction with the 1758 patent. It was Wyatt whom Daniel Bourn contacted about a grant for spindles for his Leominster mill in 1748, but this seems to have been Wyatt's last association with the spinning venture.[br]Further ReadingG.J.French, 1859, The Life and Times of Samuel Crompton, London (French collected many of the Paul and Wyatt papers; these should be read in conjunction with Hills 1970).R.L.Hills, 1970, Power in the Industrial Revolution, Manchester (Hills shows that the rollerdrafting system on this spinning machine worked on the wrong principles). A.P.Wadsworth and J.de L.Mann, 1931, The Cotton Trade and Industrial Lancashire, 1600–1780, Manchester (provides good coverage of the partnership of Paul and Wyatt and of the early mills).E.Baines, 1835, History of the Cotton Manufacture in Great Britain, London (this publication must be mentioned, although it is now out of date).W.English, 1969, The Textile Industry, London (a more recent account).W.A.Benton, "John Wyatt and the weighing of heavy loads", Transactions of the Newcomen Society 9 (for a description of Wyatt's weighing machine).RLH -
29 Nature
To Newtonians, each question had its singular answer, one that would remain the same no matter who asked it, or why. But now, the uncertainty that undercuts every measurement of some fact in the real world compels the observer to choose which question to ask, which aspect of a phenomenon to study.The necessity of choice became overwhelmingly apparent when Heisenberg elevated uncertainty to a principle in quantum mechanics in 1927, having recognized that on the subatomic level the observer had to emphasize only one of a pair of properties to study at any one time. In one of the prominent interpretations of quantum mechanics, the idea took on a larger meaning: that in choosing what to study, the scientist in effect creates the object of his inquiry.... The impossibility of constructing a complete, accurate quantitative description of a complex system forces observers to pick which aspects of the system they most wish to understand....What one studies from among this wealth of choice depends on what one wants to know; the questions create-or at least determine-the range of possible answers. No such answer can be completely "true": instead of saying "This is what nature is like," they can claim only, "This is what nature seems like from here"-a vastly diminished claim from that of Newton. The critical issue raised by such subjectivity is how to decide what value each partial answer has, what connection it actually makes between the real world and our understanding of it. The object of study, the focus of much of modern science, has therefore shifted inward, to examine not nature itself but rather to study the abstract representations of nature, the choices made of what to leave in and what to drop out of any given study. (Levenson, 1995, pp. 228-229)Historical dictionary of quotations in cognitive science > Nature
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