Algebra is a kind of generalized arithmetic, in which numbers or quantities and operations, often also the results of operations, are represented by symbols. Algebra is an invaluable instrument in intricate calculations of all kinds, and enables operations to be performed and results obtained that by arithmetic would be impossible, and its scope is still being extended.
The beginnings of algebraic method are to be found in Diophantus, a Greek of the fourth century of our era, but it was the Arabians that introduced algebra to Europe and from them it received its name. The first Arabian treatise on algebra was published in the reign of the great Kaliph Al Mamun (813-833) by Mohammed Ben Musa. In 1202 Leonardo Fibonacci of Pisa, who had travelled and studied in the East, published a work treating of algebra as then understood in the Arabian school. From this time to the discovery of printing considerable attention was given to algebra, and the work of Ben Musa and another Arabian treatise, called the Rule of Algebra, were translated into Italian.
The first printed work treating on algebra (also on arithmetic, etc) appeared at Venice in 1494, the author being a monk called Luca Pacioli da Bergo. Rapid progress now began to be made, and among the names of those to whom advances are to be attributed are Tarfcaglia and Cardan. About the middle of the sixteenth century the German Stifel introduced the plus, minus and square root symbols, and Recorde the equals sign. Recorde wrote the first English work on algebra. Francois Vieta, a French mathematician (1540-1603), first adopted the method which has led to so great an extension of modern algebra, by being the first who used general symbols for known quantities as well as for unknown. It was he also who first made the application of algebra to geometry.
Albert Girard extended the theory of equations by the supposition of imaginary quantities. The Englishman Harriot, early in the seventeenth century, discovered negative roots, and established the equality between the number of roots and the units in the degree of the equation. He also invented the less than and greater than signs, and Oughthred that of the x multiplication symbol. Descartes, though not the first to apply algebra to geometry, has, by the extent and importance of his applications, commonly acquired the credit of being so. The same discoveries have also been attributed to him as to Harriot, and their respective claims have caused much controversy. He obtained by means of algebra the definition and description of curves. Since his time algebra has been applied so widely in geometry and higher mathematics that we need only mention the names of Fermat, Wallis, Newton, Leibnitz, De Moivre, MacLaurin, Taylor, Euler, D'Alembert, Lagrange, Laplace, Fourier, Poisson, Gauss, Horner, De Morgan, Sylvester, Cayley. Boole, Jevons, and others have applied the algebraic method not only to formal logic but to political economy. Research Algebra More information about Algebra
In September 2001 the USA was attacked by letters containing the phrases 'Death to America' and 'Death to Israel' infected with anthrax being sent through the post. Five people died, 18 more were injured, and 35000 were forced to take precautionary antibiotics. Official reports suggested that the anthrax was released by the Muslim al-Qaeda terrorist movement, but investigations by forensic scientists at the FBI revealed that the sender of the poisoned letters was most likely a member of the American CIA, probably trying to encourage support for President Bush's 'war on terrorism' by spreading terror and paranoia throughout the western world directed at the more fundamental Islamic countries.
The FBI's conclusion was further proved when on the 17th of June, 2003 the head of the British intelligence service, MI5Ms Manningham-Buller, warned that an attack on a Western city was 'only a matter of time', and went on to say 'We are faced with a realistic possibility of a form of unconventional attack that could include chemical, biological, radiological or nuclear (CBRN)'. 'It is only a matter of time before a crude version of a CBRN is launched on a Western city.' Clearly indicating that to date no such terrorist attack had taken place, and that the FBI were correct in their finding that the Anthraxattack had been carried out by a member of the CIA, though suggesting that he was not a rogue criminal at all. Research Anthrax Killer
Burlesque was a type of American theatre entertainment characterised by chorus-girl numbers interspersed with comedians and other acts. It started in the mid-1800s and became very popular in the early 1900s with stars such as Al Jolson, W. C. Fields, Sophie Tucker, Fannie Brice and strippers Gypsy Rose Lee and Sally Rand. It declined with the rise of films and was finally Banned in the 1940s as a threat to public morality. Research Burlesque
A clock is an instrument for measuring time and indicating hours, minutes, and usually seconds, by means of hands moving on a dial-plate, and traditionally differing from a watch mainly in having the movement of its machinery regulated by a pendulum, and in not being portable. A clock also chimes, though the term clock is frequently, and incorrectly, applied to the non-chiming instruments for measuring time, which are technically known as a timepiece.
The use of a horologium, or hour-teller, was common even amongst the ancients, but their time-pieces were nothing else than sun-dials, hour-glasses, and clepsydrae. In the earlier half of our era we have accounts of several attempts at clock construction : that of Boethius in the 6th century, the clock sent by Harun al Rashid to Charlemagne in 809, that made by Pacificus, archdeacon of Verona, in the 9th century, and that of PopeSylvester II in the 10th century. It is doubtful, however, if any of these was a wheel-and-weight clock, and it is probably to the monks that we owe the invention of clocks set in motion by wheels and weights. In the 12th century clocks were made use of in the monasteries, which announced the end of every hour by the sound of a bell put in motion by means of wheels. From this time forward the expression, 'the clock has struck,' is often met with. The hand for marking the time is also made mention of.
In the 14th century there are stronger traces of the later system of clock-work. Dante particularly mentions clocks. Richard, abbot of St Albans in England, made a clock in 1326, such as had never been heard of until then. It not only indicated the course of the sun and moon, but also the ebb and flood tide. Large clocks on steeples likewise were first made use of in the 14th century. Watches are a much later invention, although they have likewise been said to have been invented as early as the 14th century. A celebrated clock, the construction of which is well known, was set up in Paris for Charles V in 1379, the maker being Henry de Vick, a German. It probably formed a model on which clocks were constructed for nearly 300 years, and until Huyghens applied the pendulum to clock-work as the regulating power, about 1657. The great advantage of the pendulum prior to the invention of electronic oscillators is that the beats or oscillations of a pendulum all occupy substantially the same time (the time depending on its length), hence its utility in imparting regularity to a time-measurer. The mechanism by which comparative regularity was previously attained, though ingenious and simple, was far less perfect; and the first pendulum escapement that is, the contrivance by which the pendulum was connected with the clock-work, was also less perfect than others subsequently introduced, especially Graham's dead-heat escapement, invented in 1700.
In a watch, prior to the invention of electronics, the balance-wheel and spring served the same purpose as the pendulum, and the honour of being the inventor of the balance-spring was contested between Huyghens and the English pliilosopher Dr. Hooke. Various improvements followed, such as the chronometerescapement, and the addition of a compensation adjustment, by which two metals having unequal rates of expansion and contraction under variations of temperature are combined in the pendulum or the balance-wheel, so that, each metal counteracting the other, the vibrations are isochronous under any change of temperature. This arrangement was perfected by Harrison in 1726, and was especially useful in navigation. Research Clock
The ISO (International Standards Organisation) assigns a two character code to each country name. These codes are used by Internet 'whois' databases (these two character abbreviations are the whois country codes) and also other applications.
Abu Al-Fida (Abulfida) was an Arabian historian and geographer. He was born 1273 at Damascus and died in 1331 He took part in the siege of Tripoli in 1289 and the siege of Acre in 1291. In 1310 he was appointed governor of the city of Hamah, which he ruled over with almost absolute power. In 1312 he was made prince, and in 1320 he was given the title of sultan and the right to transmit the title to his descendants. His most important work was 'An Abridgment of the History of the Human Race', a book that traces humanhistory until 1329 and is especially valuable as a source for the period of the Crusades. Research Abu Al-Fida
Abu Nuwas was a Persian poet. He was born about 760 and died about 814. A favourite at the court of the caliph Harun al-Raschid in Baghdad, he is mentioned in the Arabian Nights. He abandoned older, traditional forms for erotic and witty lyrics and was considered one of the greatest poets of the 'Abbasid period. Research Abu Nuwas
AbuTammam (Abu Tamman Habib ibn Aws) was a Palestinian poet. He was born in 807 near Lake Tiberias and died in 850. He rose to favour under caliphs al-Ma'mun and al-Mutasim as a composer of panegyrics. He travelled extensively and discovered a private library of desert poetry at Hamadhan from which he compiled an anthology of early Arab poetry, the Hamasu. Research Abu Tammam
Antar was an Arabian warrior and poet of the 6th century. He was author of one of the seven Moallakas (poems) hung up in the Kaaba at Mecca; hero of a romance analogous in Arabic literature to the Arthurian legend of the English. The romance of Antar, which has been called the Iliad of the Desert, is composed in rhythmic prose interspersed with fragments of verse, many of which are attributed to Antar himself, and has been generally ascribed to Asmai who lived between 740 and 830, preceptor to Harun-al-Rashid. Research Antar
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