-
1 Volta, Alessandro Giuseppe Antonio Anastasio
SUBJECT AREA: Electricity[br]b. 18 February 1745 Como, Italyd. 5 March 1827 Como, Italy[br]Italian physicist, discoverer of a source of continuous electric current from a pile of dissimilar metals.[br]Volta had an early command of English, French and Latin, and also learned to read Dutch and Spanish. After completing studies at the Royal Seminary in Como he was involved in the study of physics, chemistry and electricity. He became a teacher of physics in his native town and in 1779 was appointed Professor of Physics at the University of Pavia, a post he held for forty years.With a growing international reputation and a wish to keep abreast of the latest developments, in 1777 he began the first of many travels abroad. A journey started in 1781 to Switzerland, Germany, Belgium, Holland, France and England lasted about one year. By 1791 he had been elected to membership of many learned societies, including those in Zurich, Berlin, Berne and Paris. Volta's invention of his pile resulted from a controversy with Luigi Galvani, Professor of Anatomy at the University of Bologna. Galvani discovered that the muscles of frogs' legs contracted when touched with two pieces of different metals and attributed this to a phenomenon of the animal tissue. Volta showed that the excitation was due to a chemical reaction resulting from the contact of the dissimilar metals when moistened. His pile comprised a column of zinc and silver discs, each pair separated by paper moistened with brine, and provided a source of continuous current from a simple and accessible source. The effectiveness of the pile decreased as the paper dried and Volta devised his crown of cups, which had a longer life. In this, pairs of dissimilar metals were placed in each of a number of cups partly filled with an electrolyte such as brine. Volta first announced the results of his experiments with dissimilar metals in 1800 in a letter to Sir Joseph Banks, President of the Royal Society. This letter, published in the Transactions of the Royal Society, has been regarded as one of the most important documents in the history of science. Large batteries were constructed in a number of laboratories soon after Volta's discoveries became known, leading immediately to a series of developments in electrochemistry and eventually in electromagnetism. Volta himself made little further contribution to science. In recognition of his achievement, at a meeting of the International Electrical Congress in Paris in 1881 it was agreed to name the unit of electrical pressure the "volt".[br]Principal Honours and DistinctionsFRS 1791. Royal Society Copley Medal 1794. Knight of the Iron Crown, Austria, 1806. Senator of the Realm of Lombardy 1809.Bibliography1800, Philosophical Transactions of the Royal Society 18:744–6 (Volta's report on his discovery).Further ReadingG.Polvani, 1942, Alessandro Volta, Pisa (the best account available).B.Dibner, 1964, Alessandro Volta and the Electric Battery, New York (a detailed account).C.C.Gillispie (ed.), 1976, Dictionary of Scientific Biography, Vol. XIV, New York, pp.66–82 (includes an extensive biography).F.Soresni, 1988, Alessandro Volta, Milan (includes illustrations of Volta's apparatus, with brief text).GWBiographical history of technology > Volta, Alessandro Giuseppe Antonio Anastasio
-
2 Tainter, Charles Sumner
SUBJECT AREA: Recording[br]b. 1854d. 1940[br]American scientific instrument maker, co-developer of practical cylinder recording.[br]He manufactured "philosophical devices" in Cambridge, Massachusetts, and was approached by Alexander Graham Bell in connection with the construction of toys using sound recordings. A more formal co-operation was agreed, and after Bell's receipt of the French Volta prize in 1880 he financed the Volta Laboratory Association in Washington, DC. He founded this in 1881 together with a cousin and Tainter to develop a practical sound-recording and -reproducing system. Another area that was developed was the transmission of sound by means of modulated light and reception via a selenium cell.The advances in sound recording and reproduction were very positive, and T.A. Edison was approached in mid-1885 in order to establish co-operation in the further development of a cylinder instrument. In early 1886 the Volta Graphophone Company was incorporated in Virginia, and an experimental laboratory was established in Washington, DC. The investors were connected with the secretarial services at the House of Representatives and needed the development for increasing efficiency in debate reporting. In mid-1887 Edison, against the advice of his collaborators, declined co-operation and went ahead on his own. There is no doubt that Tainter's skill in developing functional equipment and the speed with which he was able to work in the crucial years provoked other developments in the field, in particular the perfection of the Edison phonograph and the development of the disc record by Berliner.[br]BibliographyTainter's patents were numerous; those on sound recording were the most important, because they incorporated so many fundamental ideas, and included US patent no. 341, 214 (with C.A.Bell), and US patent no. 375, 579 (a complete dictation outfit).Further ReadingV.K.Chew, 1981, Talking Machines, London: Science Museum and HMSO, pp. 9–12 (provides a good overview, not only of Tainter's contribution, but also of early sound recording and reproduction).GB-NBiographical history of technology > Tainter, Charles Sumner
-
3 Cruickshank, William
SUBJECT AREA: Electricity[br]d. 1810/11 Scotland[br]Scottish chemist and surgeon, inventor of a trough battery developed from Volta's pile.[br]Cruickshank graduated MA from King's College, Aberdeen, in 1765, and later gained a Diploma of the Royal College of Surgeons. When chemistry was introduced in 1788 into the course at the Royal Military Academy in Woolwich, Cruickshank became a member of staff, serving as Assistant to Dr A.Crawford, the Lecturer in Chemistry. Upon Crawford's death in 1796 Cruickshank succeeded him as Lecturer and held the post until his retirement due to ill health in 1804. He also held the senior posts of Chemist to the Ordnance at Woolwich and Surgeon to the Ordnance Medical Department. He should not be confused with William Cumberland Cruickshank (1745–1800), who was also a surgeon and Fellow of the Royal Society. In 1801, shortly after Volta's announcement of his pile, Cruickshank built a voltaic pile to facilitate his experiments in electrochemistry. The pile had zinc and silver plates about 1½ in2 (10 cm2) with interposed papers moistened with ammonium chloride. Dissatisfied with this arrangement, Cruickshank devised a horizontal trough battery in which a wooden box was divided into cells, each holding a pair of zinc and silver or zinc and copper plates. Charged with a dilute solution of ammonium chloride, the battery, which was typically of sixty cells, was found to be more convenient to use than a pile and it, or a derivative, was generally adopted for electrochemical experiments including tose of Humphrey Davy during the early years of the nineteenth century.[br]Principal Honours and DistinctionsFRS 1802.Bibliography1801, article in Nicholsons Journal 4:187–91 (describes Cruickshank's original pile). 1801, article in Nicholsons Journal 4:245–64 (describes his trough battery).Further ReadingB.Bowers, 1982, A History of Electric Light and Power, London (a short account). A.Courts, 1959, "William Cruickshank", Annals of Science 15:121–33 GW -
4 Sports, Portuguese
Among the many sports enjoyed in Portugal, soccer ( futebol) is by far the most popular, with some observers claiming that it approaches a semireligious movement. In international competition, although Portugal's national team boasts world-class players like Cristiano Ronaldo and Luis Figo, and nourishes fond memories of "Eusébio" from the 1960s world cup matches, Portugal has never won a World Cup. It has garnered individual titles in the Euro soccer cup. A ferocious rivalry among professional soccer clubs continues, as fans of clubs such as Sporting and Benfica demonstrate.In recent decades, Portuguese athletes have excelled in world track and field competitions, and Olympic gold medals have been won by athletes such as Vanessa Fernandes, Rui Silva, and Naide Gomes. Portuguese teams have been highly competitive in the fast, popular sport of rink hockey, also called hardball hockey or roller hockey (quad), or, in the Portuguese language, hoquei em patins. Since the 1940s, Portugal has won 15 world titles, in hot competition with rivals Spain (13 world titles), Italy (4), and Argentina (4). Among other popular sports in Portugal is cycling, and the principal cycle competition in Portugal is the Volta a Portugal. In recent years, rugby has attained a new popularity in Portugal, and Portuguese rugby teams have been improving. In judo, Portugal has a young European champion in Telma Monteiro. Equestrianism has long been a sport of consequence, although traditionally viewed as a largely elite activity. Bull- fighting continues, but its popularity has slipped and the activity's future remains uncertain. In a country with a substantial Atlantic coast, Portugal has taken to popular water sports, such as sailing, windsurfing, kayaking, surfing, swimming, and kite-surfing. Motor sports, such as international car racing, also have a growing number of fans. -
5 Berliner, Emile
SUBJECT AREA: Recording[br]b. 20 May 1851 Hannover, Germanyd. 3 August 1929 Montreal, Canada[br]German (naturalized American) inventor, developer of the disc record and lateral mechanical replay.[br]After arriving in the USA in 1870 and becoming an American citizen, Berliner worked as a dry-goods clerk in Washington, DC, and for a period studied electricity at Cooper Union for the Advancement of Science and Art, New York. He invented an improved microphone and set up his own experimental laboratory in Washington, DC. He developed a microphone for telephone use and sold the rights to the Bell Telephone Company. Subsequently he was put in charge of their laboratory, remaining in that position for eight years. In 1881 Berliner, with his brothers Joseph and Jacob, founded the J.Berliner Telephonfabrik in Hanover, the first factory in Europe specializing in telephone equipment.Inspired by the development work performed by T.A. Edison and in the Volta Laboratory (see C.S. Tainter), he analysed the existing processes for recording and reproducing sound and in 1887 developed a process for transferring lateral undulations scratched in soot into an etched groove that would make a needle and diaphragm vibrate. Using what may be regarded as a combination of the Phonautograph of Léon Scott de Martinville and the photo-engraving suggested by Charles Cros, in May 1887 he thus demonstrated the practicability of the laterally recorded groove. He termed the apparatus "Gramophone". In November 1887 he applied the principle to a glass disc and obtained an inwardly spiralling, modulated groove in copper and zinc. In March 1888 he took the radical step of scratching the lateral vibrations directly onto a rotating zinc disc, the surface of which was protected, and the subsequent etching created the groove. Using well-known principles of printing-plate manufacture, he developed processes for duplication by making a negative mould from which positive copies could be pressed in a thermoplastic compound. Toy gramophones were manufactured in Germany from 1889 and from 1892–3 Berliner manufactured both records and gramophones in the USA. The gramophones were hand-cranked at first, but from 1896 were based on a new design by E.R. Johnson. In 1897–8 Berliner spread his activities to England and Germany, setting up a European pressing plant in the telephone factory in Hanover, and in 1899 a Canadian company was formed. Various court cases over patents removed Berliner from direct running of the reconstructed companies, but he retained a major economic interest in E.R. Johnson's Victor Talking Machine Company. In later years Berliner became interested in aeronautics, in particular the autogiro principle. Applied acoustics was a continued interest, and a tile for controlling the acoustics of large halls was successfully developed in the 1920s.[br]Bibliography16 May 1888, Journal of the Franklin Institute 125 (6) (Lecture of 16 May 1888) (Berliner's early appreciation of his own work).1914, Three Addresses, privately printed (a history of sound recording). US patent no. 372,786 (basic photo-engraving principle).US patent no. 382,790 (scratching and etching).US patent no. 534,543 (hand-cranked gramophone).Further ReadingR.Gelatt, 1977, The Fabulous Phonograph, London: Cassell (a well-researched history of reproducible sound which places Berliner's contribution in its correct perspective). J.R.Smart, 1985, "Emile Berliner and nineteenth-century disc recordings", in WonderfulInventions, ed. Iris Newson, Washington, DC: Library of Congress, pp. 346–59 (provides a reliable account).O.Read and W.L.Welch, 1959, From Tin Foil to Stereo, Indianapolis: Howard W.Sams, pp. 119–35 (provides a vivid account, albeit with less precision).GB-N -
6 Davy, Sir Humphry
[br]b. 17 December 1778 Penzance, Cornwall, Englandd. 29 May 1829 Geneva, Switzerland[br]English chemist, discoverer of the alkali and alkaline earth metals and the halogens, inventor of the miner's safety lamp.[br]Educated at the Latin School at Penzance and from 1792 at Truro Grammar School, Davy was apprenticed to a surgeon in Penzance. In 1797 he began to teach himself chemistry by reading, among other works, Lavoisier's elementary treatise on chemistry. In 1798 Dr Thomas Beddoes of Bristol engaged him as assistant in setting up his Pneumatic Institution to pioneer the medical application of the newly discovered gases, especially oxygen.In 1799 he discovered the anaesthetic properties of nitrous oxide, discovered not long before by the chemist Joseph Priestley. He also noted its intoxicating qualities, on account of which it was dubbed "laughing-gas". Two years later Count Rumford, founder of the Royal Institution in 1800, appointed Davy Assistant Lecturer, and the following year Professor. His lecturing ability soon began to attract large audiences, making science both popular and fashionable.Davy was stimulated by Volta's invention of the voltaic pile, or electric battery, to construct one for himself in 1800. That enabled him to embark on the researches into electrochemistry by which is chiefly known. In 1807 he tried decomposing caustic soda and caustic potash, hitherto regarded as elements, by electrolysis and obtained the metals sodium and potassium. He went on to discover the metals barium, strontium, calcium and magnesium by the same means. Next, he turned his attention to chlorine, which was then regarded as an oxide in accordance with Lavoisier's theory that oxygen was the essential component of acids; Davy failed to decompose it, however, even with the aid of electricity and concluded that it was an element, thus disproving Lavoisier's view of the nature of acids. In 1812 Davy published his Elements of Chemical Philosophy, in which he presented his chemical ideas without, however, committing himself to the atomic theory, recently advanced by John Dalton.In 1813 Davy engaged Faraday as Assistant, perhaps his greatest service to science. In April 1815 Davy was asked to assist in the development of a miner's lamp which could be safely used in a firedamp (methane) laden atmosphere. The "Davy lamp", which emerged in January 1816, had its flame completely surrounded by a fine wire mesh; George Stephenson's lamp, based on a similar principle, had been introduced into the Northumberland pits several months earlier, and a bitter controversy as to priority of invention ensued, but it was Davy who was awarded the prize for inventing a successful safety lamp.In 1824 Davy was the first to suggest the possibility of conferring cathodic protection to the copper bottoms of naval vessels by the use of sacrificial electrodes. Zinc and iron were found to be equally effective in inhibiting corrosion, although the scheme was later abandoned when it was found that ships protected in this way were rapidly fouled by weeds and barnacles.[br]Principal Honours and DistinctionsKnighted 1812. FRS 1803; President, Royal Society 1820. Royal Society Copley Medal 1805.Bibliography1812, Elements of Chemical Philosophy.1839–40, The Collected Works of Sir Humphry Davy, 9 vols, ed. John Davy, London.Further ReadingJ.Davy, 1836, Memoirs of the Life of Sir Humphry Davy, London (a classic biography). J.A.Paris, 1831, The Life of Sir Humphry Davy, London (a classic biography). H.Hartley, 1967, Humphry Davy, London (a more recent biography).J.Z.Fullmer, 1969, Cambridge, Mass, (a bibliography of Davy's works).ASD -
7 Electricity
-
8 Page, Charles Grafton
[br]b. 25 January 1812 Salem, Massachusetts, USAd. 5 May 1868 Washington, DC, USA[br]American scientist and inventor of electric motors.[br]Page graduated from Harvard in 1832 and subsequently attended Boston Medical School. He began to practise in Salem and also engaged in experimental research in electricity, discovering the improvement effected by substituting bundles of iron wire for solid bars in induction coils. He also created a device which he termed a Dynamic Multiplier, the prototype of the auto-transformer. Following a period in medical practice in Virginia, in 1841 he became one of the first two principal examiners in the United States Patent Office. He also held the Chair of Chemistry and Pharmacy at Columbian College, later George Washington University, between 1844 and 1849.A prolific inventor, Page completed several large electric motors in which reciprocating action was converted to rotary motion, and invested an extravagant sum of public money in a foredoomed effort to develop a 10-ton electric locomotive powered by primary batteries. This was unsuccessfully demonstrated in April 1851 on the Washington-Baltimore railway and seriously damaged his reputation. Page approached Thomas Davenport with an offer of partnership, but Davenport refused.After leaving the Patent Office in 1852 he became a patentee himself and advocated the reform of the patent procedures. Page returned to the Patent Office in 1861, and later persuaded Congress to pass a special Act permitting him to patent the induction coil. This was the cause, after his death, of protracted and widely publicized litigation.[br]Bibliography1867, History of Induction: The American Claim to the Induction Coil and itsElectrostatic Developments, Washington, DC.Further ReadingR.C.Post, 1976, Physics, Patents and Politics, New York (a biography which treats Page as a focal point for studying the American patent system).——1976, "Stray sparks from the induction coil: the Volta prize and the Page patent", Proceedings of the Institute of Electrical Engineers 64: 1,279–86 (a short account).W.J.King, 1962, The Development of Electrical Technology in the 19th Century, Washington, DC: Smithsonian Institution, Paper 28.GW
См. также в других словарях:
volta (1) — {{hw}}{{volta (1)}{{/hw}}s. f. 1 Atto del voltare o del voltarsi | Svolta: la strada fa una volta | Dar –v, dar la –v, dar di volta il cervello, uscir di senno. 2 (mar.) Attorcigliamento d un cavo. 3 (aeron.) Gran –v, figura acrobatica per cui un … Enciclopedia di italiano
Volta — may refer to:Rivers and lakes* Lake Volta in Ghana * Burkina Faso, the country formerly named Upper Volta * The Volta River, consisting of the: ** Black Volta ** Red Volta ** White VoltaOther* Alessandro Volta, an Italian physicist and inventor… … Wikipedia
volta — s. f. 1. Ato de regressar a um lugar donde se partira. 2. Ato de virar ou de se virar. 3. Resposta, réplica. 4. Retorno; troco; demasia. 5. Movimento circular, giro. 6. Ato de percorrer a circunferência de. 7. Ação de volver. 8. Vicissitude.… … Dicionário da Língua Portuguesa
volta — vólta interj. Trimis de siveco, 03.06.2008. Sursa: Dicţionar ortografic vólta (muz.) s. f. Trimis de siveco, 03.06.2008. Sursa: Dicţionar ortografic VÓLTA s.f. (muz.) Semn de repetiţie care arată măsurile finale ce trebuie să fie executate… … Dicționar Român
Volta — bezeichnet: Volta (Fluss), ein Fluss in Nordwestafrika Volta Stausee, ein Stausee in Nordwestafrika Volta Region, eine Region des afrikanischen Staates Ghana Volta (Tanz), ein Tanz des 16. Jahrhunderts im 3/4 Takt aus der Provence Volta (Album),… … Deutsch Wikipedia
Volta — Volta … Википедия
voltă — VÓLTĂ, volte, s.f. 1. Mişcare în formă de cerc sau de arc de cerc. ♦ fig. Schimbare (bruscă) în atitudine, trecere subită de la o concepţie la alta. ♦ (Scrimă) Mişcare (de rotaţie) făcută pentru a evita loviturile adversarului. 2. Manevră de… … Dicționar Român
volta — (Alessandro, comte) (1745 1827) physicien italien. Pionnier de l électricité, il réalisa la première pile électrique (1800). Volta (la) fl. du Ghana (1 600 km), tributaire de l Atlantique, formé par la réunion de la Volta noire, à l O., de la… … Encyclopédie Universelle
Volta — Volta1 [vō̂l′tä] Conte Alessandro [ä΄les sän′drō̂] 1745 1827; It. physicist Volta2 [väl′tə, vôl′tə, vōl′tə] 1. river in SE Ghana, flowing south from Lake Volta into the Bight of Benin: c. 300 mi (483 km), including Lake Volta 2. Lake artificial … English World dictionary
Volta — Vol ta, n.; pl. {Volte}. [It. volta a turn, turning, a time. See {Volt} a tread.] (Mus.) A turning; a time; chiefly used in phrases signifying that the part is to be repeated one, two, or more times; as, una volta, once. Seconda volta, second… … The Collaborative International Dictionary of English
Volta — Volta, Alessandro, Graf, der berühmte Physiker, geb. 1745 zu Como, ward Professor der Physik daselbst, dann zu Pavia, machte bedeutende Reisen, ward 1802 Mitglied des franz. Instituts, von Napoleon I. zum Grafen u. von Kaiser Franz 1815 zum… … Herders Conversations-Lexikon
