New England Trials Association

1) Компьютерная техника: Nebraska Educational Technology Association

2) Военный термин: Northeast Test Area

3) Гинекология: Норэтистерона Ацетат

4) Энергосистемы: New Trading Arrangements

5) Электротехника: Международная ассоциация по электрическим испытаниям (InterNational Electrical Testing Association)

6) НАСДАК: Network Associates, Inc.

7) Хобби: New England Trials Association

SUBJECT AREA: Metallurgy

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The most valuable part of Bessemer's education took place in the workshop of his inventor father. At the age of only 17 he went to London to seek his fortune and set himself up in the trade of casting art works in white metal. He went on to the embossing of metals and other materials and this led to his first major invention, whereby a date was incorporated in the die for embossing seals, thus preventing the wholesale forgeries that had previously been committed. For this, a grateful Government promised Bessemer a paid position, a promise that was never kept; recognition came only in 1879 with a belated knighthood. Bessemer turned to other inventions, mainly in metalworking, including a process for making bronze powder and gold paint. After he had overcome technical problems, the process became highly profitable, earning him a considerable income during the forty years it was in use.

The Crimean War presented inventors such as Bessemer with a challenge when weaknesses in the iron used to make the cannon became apparent. In 1856, at his Baxter House premises in St Paneras, London, he tried fusing cast iron with steel. Noticing the effect of an air current on the molten mixture, he constructed a reaction vessel or converter in which air was blown through molten cast iron. There was a vigorous reaction which nearly burned the house down, and Bessemer found the iron to be almost completely decarburized, without the slag threads always present in wrought iron. Bessemer had in fact invented not only a new process but a new material, mild steel. His paper "On the manufacture of malleable iron and steel without fuel" at the British Association meeting in Cheltenham later that year created a stir. Bessemer was courted by ironmasters to license the process. However, success was short-lived, for they found that phosphorus in the original iron ore passed into the metal and rendered it useless. By chance, Bessemer had used in his trials pig-iron, derived from haematite, a phosphorus-free ore. Bessemer tried hard to overcome the problem, but lacking chemical knowledge he resigned himself to limiting his process to this kind of pig-iron. This limitation was removed in 1879 by Sidney Gilchrist Thomas, who substituted a chemically basic lining in the converter in place of the acid lining used by Bessemer. This reacted with the phosphorus to form a substance that could be tapped off with the slag, leaving the steel free from this harmful element. Even so, the new material had begun to be applied in engineering, especially for railways. The open-hearth process developed by Siemens and the Martin brothers complemented rather than competed with Bessemer steel. The widespread use of the two processes had a revolutionary effect on mechanical and structural engineering and earned Bessemer around £1 million in royalties before the patents expired.

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SUBJECT AREA: Ports and shipping

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Froude was educated at a preparatory school at Buckfastleigh, and then at Westminster School, London, before entering Oriel College, Oxford, to read mathematics and classics. Between 1836 and 1838 he served as a pupil civil engineer, and then he joined the staff of Isambard Kingdom Brunel on various railway engineering projects in southern England, including the South Devon Atmospheric Railway. He retired from professional work in 1846 and lived with his invalid father at Dartington Parsonage. The next twenty years, while apparently unproductive, were important to Froude as he concentrated his mind on difficult mathematical and scientific problems. Froude married in 1839 and had five children, one of whom, Robert Edmund Froude (1846–1924), was to succeed him in later years in his research work for the Admiralty. Following the death of his father, Froude moved to Paignton, and there commenced his studies on the resistance of solid bodies moving through fluids. Initially these were with hulls towed through a house roof storage tank by wires taken over a pulley and attached to falling weights, but the work became more sophisticated and was conducted on ponds and the open water of a creek near Dartmouth. Froude published work on the rolling of ships in the second volume of the Transactions of the then new Institution of Naval Architects and through this became acquainted with Sir Edward Reed. This led in 1870 to the Admiralty's offer of £2,000 towards the cost of an experimental tank for ship models at Torquay. The tank was completed in 1872 and tests were carried out on the model of HMS Greyhound following full-scale towing trials which had commenced on the actual ship the previous year. From this Froude enunciated his Law of Comparisons, which defines the rules concerning the relationship of the power required to move geometrically similar floating bodies across fluids. It enabled naval architects to predict, from a study of a much less expensive and smaller model, the resistance to motion and the power required to move a full-size ship. The work in the tank led Froude to design a model-cutting machine, dynamometers and machinery for the accurate ruling of graph paper. Froude's work, and later that of his son, was prodigious and covered many fields of ship design, including powering, propulsion, rolling, steering and stability. In only six years he had stamped his academic authority on the new science of hydrodynamics, served on many national committees and corresponded with fellow researchers throughout the world. His health suffered and he sailed for South Africa to recuperate, but he contracted dysentery and died at Simonstown. He will be remembered for all time as one of the greatest "fathers" of naval architecture.

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