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21 videoconferencing
Gen Mgtthe use of a live video link to connect people in different locations so that they can see and hear one another and conduct real-time meetings. Videoconferencing is a useful tool for managing communication with remote workers, between staff at geographically dispersed offices, including those who form a virtual team, or with clients at remote locations. It is also used in distance learning courses.There are two basic options for videoconferencing. The more expensive option is full-blown videoconferencing using ISDN lines, dedicated equipment, and large screens, which guarantee a higher quality experience. Cheaper and more common is the PC/Web-based videoconferencing, which piggybacks on existing PC and Internet technology, and occupies a small box window on a PC. However, it is less reliable, and still requires an ISDN line to achieve any degree of quality. -
22 Ramsbottom, John
[br]b. 11 September 1814 Todmorden, Lancashire, Englandd. 20 May 1897 Alderley Edge, Cheshire, England[br]English railway engineer, inventor of the reversing rolling mill.[br]Ramsbottom's initial experience was gained at the locomotive manufacturers Sharp, Roberts \& Co. At the age of 28 he was Manager of the Longsight works of the Manchester \& Birmingham Railway, which, with other lines, became part of the London \& North Western Railway (L \& NWR) in 1846. Ramsbottom was appointed Locomotive Superintendent of its north-eastern division. Soon after 1850 came his first major invention, that of the split-ring piston, consisting of castiron rings fitted round the piston to ensure a steam-tight fit in the cylinder. This proved to be successful, with a worldwide application. In 1856 he introduced sight-feed lubrication and the form of safety valve that bears his name. In 1857 he became Locomotive Superintendent of the L \& NWR at Crewe, producing two notable classes of locomotives: 2–4–0s for passenger traffic; and 0–6–0s for goods. They were of straightforward design and robust construction, and ran successfully for many years. His most spectacular railway invention was the water trough between the rails which enabled locomotives to replenish their water tanks without stopping.As part of his policy of making Crewe works as independent as possible, Ramsbottom made several metallurgical innovations. He installed one of the earliest Bessemer converters for steelmaking. More important, in 1866 he coupled the engine part of a railway engine to a two-high rolling mill so that the rolls could be run in either direction, and quickly change direction, by means of the standard railway link reversing gear. This greatly speeded up the rolling of iron or steel into the required sections. He eventually retired in 1871.[br]Further ReadingJ.N.Weatwood, 1977, Locomotive Designers in the Age of Steam, London: Sidgwick \& Jackson, pp. 43–7.W.K.V.Gale, 1969, Iron and Steel, London: Longmans, p. 80 (provides brief details of his reversing mill).F.C.Hammerton, 1937, John Ramsbottom, the Father of the Modern Locomotive,London.LRD -
23 Stephenson, Robert
[br]b. 16 October 1803 Willington Quay, Northumberland, Englandd. 12 October 1859 London, England[br]English engineer who built the locomotive Rocket and constructed many important early trunk railways.[br]Robert Stephenson's father was George Stephenson, who ensured that his son was educated to obtain the theoretical knowledge he lacked himself. In 1821 Robert Stephenson assisted his father in his survey of the Stockton \& Darlington Railway and in 1822 he assisted William James in the first survey of the Liverpool \& Manchester Railway. He then went to Edinburgh University for six months, and the following year Robert Stephenson \& Co. was named after him as Managing Partner when it was formed by himself, his father and others. The firm was to build stationary engines, locomotives and railway rolling stock; in its early years it also built paper-making machinery and did general engineering.In 1824, however, Robert Stephenson accepted, perhaps in reaction to an excess of parental control, an invitation by a group of London speculators called the Colombian Mining Association to lead an expedition to South America to use steam power to reopen gold and silver mines. He subsequently visited North America before returning to England in 1827 to rejoin his father as an equal and again take charge of Robert Stephenson \& Co. There he set about altering the design of steam locomotives to improve both their riding and their steam-generating capacity. Lancashire Witch, completed in July 1828, was the first locomotive mounted on steel springs and had twin furnace tubes through the boiler to produce a large heating surface. Later that year Robert Stephenson \& Co. supplied the Stockton \& Darlington Railway with a wagon, mounted for the first time on springs and with outside bearings. It was to be the prototype of the standard British railway wagon. Between April and September 1829 Robert Stephenson built, not without difficulty, a multi-tubular boiler, as suggested by Henry Booth to George Stephenson, and incorporated it into the locomotive Rocket which the three men entered in the Liverpool \& Manchester Railway's Rainhill Trials in October. Rocket, was outstandingly successful and demonstrated that the long-distance steam railway was practicable.Robert Stephenson continued to develop the locomotive. Northumbrian, built in 1830, had for the first time, a smokebox at the front of the boiler and also the firebox built integrally with the rear of the boiler. Then in Planet, built later the same year, he adopted a layout for the working parts used earlier by steam road-coach pioneer Goldsworthy Gurney, placing the cylinders, for the first time, in a nearly horizontal position beneath the smokebox, with the connecting rods driving a cranked axle. He had evolved the definitive form for the steam locomotive.Also in 1830, Robert Stephenson surveyed the London \& Birmingham Railway, which was authorized by Act of Parliament in 1833. Stephenson became Engineer for construction of the 112-mile (180 km) railway, probably at that date the greatest task ever undertaken in of civil engineering. In this he was greatly assisted by G.P.Bidder, who as a child prodigy had been known as "The Calculating Boy", and the two men were to be associated in many subsequent projects. On the London \& Birmingham Railway there were long and deep cuttings to be excavated and difficult tunnels to be bored, notoriously at Kilsby. The line was opened in 1838.In 1837 Stephenson provided facilities for W.F. Cooke to make an experimental electrictelegraph installation at London Euston. The directors of the London \& Birmingham Railway company, however, did not accept his recommendation that they should adopt the electric telegraph and it was left to I.K. Brunel to instigate the first permanent installation, alongside the Great Western Railway. After Cooke formed the Electric Telegraph Company, Stephenson became a shareholder and was Chairman during 1857–8.Earlier, in the 1830s, Robert Stephenson assisted his father in advising on railways in Belgium and came to be increasingly in demand as a consultant. In 1840, however, he was almost ruined financially as a result of the collapse of the Stanhope \& Tyne Rail Road; in return for acting as Engineer-in-Chief he had unwisely accepted shares, with unlimited liability, instead of a fee.During the late 1840s Stephenson's greatest achievements were the design and construction of four great bridges, as part of railways for which he was responsible. The High Level Bridge over the Tyne at Newcastle and the Royal Border Bridge over the Tweed at Berwick were the links needed to complete the East Coast Route from London to Scotland. For the Chester \& Holyhead Railway to cross the Menai Strait, a bridge with spans as long-as 460 ft (140 m) was needed: Stephenson designed them as wrought-iron tubes of rectangular cross-section, through which the trains would pass, and eventually joined the spans together into a tube 1,511 ft (460 m) long from shore to shore. Extensive testing was done beforehand by shipbuilder William Fairbairn to prove the method, and as a preliminary it was first used for a 400 ft (122 m) span bridge at Conway.In 1847 Robert Stephenson was elected MP for Whitby, a position he held until his death, and he was one of the exhibition commissioners for the Great Exhibition of 1851. In the early 1850s he was Engineer-in-Chief for the Norwegian Trunk Railway, the first railway in Norway, and he also built the Alexandria \& Cairo Railway, the first railway in Africa. This included two tubular bridges with the railway running on top of the tubes. The railway was extended to Suez in 1858 and for several years provided a link in the route from Britain to India, until superseded by the Suez Canal, which Stephenson had opposed in Parliament. The greatest of all his tubular bridges was the Victoria Bridge across the River St Lawrence at Montreal: after inspecting the site in 1852 he was appointed Engineer-in-Chief for the bridge, which was 1 1/2 miles (2 km) long and was designed in his London offices. Sadly he, like Brunel, died young from self-imposed overwork, before the bridge was completed in 1859.[br]Principal Honours and DistinctionsFRS 1849. President, Institution of Mechanical Engineers 1849. President, Institution of Civil Engineers 1856. Order of St Olaf (Norway). Order of Leopold (Belgium). Like his father, Robert Stephenson refused a knighthood.Further ReadingL.T.C.Rolt, 1960, George and Robert Stephenson, London: Longman (a good modern biography).J.C.Jeaffreson, 1864, The Life of Robert Stephenson, London: Longman (the standard nine-teenth-century biography).M.R.Bailey, 1979, "Robert Stephenson \& Co. 1823–1829", Transactions of the Newcomen Society 50 (provides details of the early products of that company).J.Kieve, 1973, The Electric Telegraph, Newton Abbot: David \& Charles.PJGR
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