crème de la crème

Jai Ganesh · 2016-05-02 23:06:12

123. Robert Edwin Peary, (born May 6, 1856, Cresson, Pennsylvania, U.S.—died February 20, 1920, Washington, D.C.) U.S. Arctic explorer usually credited with leading the first expedition to reach the North Pole (1909).

Peary entered the U.S. Navy in 1881 and pursued a naval career until his retirement, with leaves of absence granted for Arctic exploration. In 1886—with Christian Maigaard, who was the Danish assistant governor of Ritenbenk, Greenland, and two native Greenlanders—he traveled inland from Disko Bay over the Greenland ice sheet for 161 km (100 miles), reaching a point 2,288 metres (7,500 feet) above sea level. Peary hired African American explorer Matthew Henson, who would accompany him on several expeditions, as his assistant in 1887. In 1891 Peary ventured again to Greenland with seven companions—a party that included his wife, Josephine, in addition to Henson and American physician and explorer Frederick A. Cook, who in 1909 would claim to have reached the North Pole before Peary. On this expedition Peary sledged 2,100 km (1,300 miles) to northeastern Greenland, discovered Independence Fjord, and found evidence of Greenland’s being an island. He also studied the “Arctic Highlanders,” an isolated Eskimo tribe who helped him greatly on later expeditions.

During his expedition of 1893–94 he again sledged to northeastern Greenland—this time in his first attempt to reach the North Pole. On summer trips in 1895 and 1896 he was mainly occupied in transporting masses of meteoric iron from Greenland to the United States. Between 1898 and 1902 he reconnoitred routes to the pole from Etah, in Inglefield Land, northwestern Greenland, and from Fort Conger, Ellesmere Island, in the Canadian Northwest Territories. On a second attempt to reach the pole he was provided with a ship built to his specifications, the Roosevelt, which he sailed to Cape Sheridan, Ellesmere Island, in 1905. But the sledging season was unsuccessful owing to adverse weather and ice conditions, and his party reached only 87°06′ N.

Peary returned to Ellesmere in 1908 for his third attempt and early the following March left Cape Columbia on his successful journey to the pole. On the last stage of the trek he was accompanied by Henson and four Inuit. Peary and his companions purportedly reached the North Pole on April 6, 1909. Peary returned to civilization only to discover that his former colleague, Cook, was claiming to have reached the North Pole independently in April 1908. Cook’s claim, though subsequently discredited, marred Peary’s enjoyment of his triumph. In 1911 Peary retired from the navy with the rank of rear admiral. His published works include Northward over the “Great Ice” (1898), The North Pole (1910), and Secrets of Polar Travel (1917).

Peary’s claim to have reached the North Pole was almost universally accepted, but in the 1980s the examination of his 1908–09 expedition diary and other newly released documents cast doubt on whether he had actually reached the pole. Through a combination of navigational mistakes and record-keeping errors, Peary may actually have advanced only to a point 50–100 km (30–60 miles) short of the pole. The truth remains uncertain.

Jai Ganesh · 2016-05-03 16:36:36

124. Ted Turner

Ted Turner, byname of Robert Edward Turner III (born Nov. 19, 1938, Cincinnati, Ohio, U.S.) broadcasting entrepreneur and sportsman who became a major figure in American business in the late 20th century.

Turner attended but did not graduate from Brown University. After stints as an account executive for the billboard-advertising company owned by his father and based in Atlanta, Ga., Turner became the general manager of one of the company’s branch offices in 1960. Following his father’s death in 1963, Turner took over the ailing family business and restored it to profitability.

In 1970 he purchased a financially troubled UHF television station in Atlanta, and within three years he had made it one of the few truly profitable independent stations in the United States. In 1975 Turner’s company was one of the first to use a new communications satellite to broadcast his station (later renamed WTBS, or TBS, the Turner Broadcasting System) to a nationwide cable television audience, thereby greatly increasing revenues. Turner went on to create two other highly successful and innovative cable television networks: CNN (Cable News Network; 1980) and TNT (Turner Network Television; 1988). He also purchased the Atlanta Braves major league baseball team in 1976 and the Atlanta Hawks professional basketball team in 1977. Turner was a noted yachtsman as well, and he piloted Courageous to win the America’s Cup in 1977. In 1986 he bought the MGM/UA Entertainment Company, which included the former Metro-Goldwyn-Mayer motion-picture studio and its library of more than 4,000 films. Turner set off a storm of protest from the film community and film critics when he authorized the “colourizing” of some of the library’s black-and-white motion pictures.

The large debt burden sustained from his MGM and other purchases compelled Turner to subsequently sell off not only MGM/UA but also a sizable share of the Turner Broadcasting System, Inc., though he retained control of it. He also kept ownership of the MGM film library, which included many Hollywood classics. He also founded and sponsored the Goodwill Games (1986–2001), citing his hope of easing Cold War tensions through friendly athletic competition. He married actress-activist Jane Fonda in 1991; they divorced in 2001.

Turner resumed the expansion of his media empire in the 1990s with the creation of the Cartoon Network (1992) and the purchase (1993) of two motion-picture production companies, New Line Cinema and Castle Rock Entertainment. In 1996 the media giant Time Warner Inc. acquired the Turner Broadcasting System for $7.5 billion. As part of the agreement, Turner became a vice-chairman of Time Warner and headed all of the merged company’s cable television networks. When Time Warner merged with Internet company AOL, Turner became vice-chairman and senior adviser of AOL Time Warner Inc. In 2003 he resigned as vice-chairman of that company. Also in 2003, Turner both produced and starred in the films Gods and Generals and Gettysburg. In 2006 he received the Bower Award for Business Leadership from the Franklin Institute—a premier science and technology education and development centre in Philadelphia. That same year, Turner announced that he would not seek reelection to Time Warner’s board of directors. In April 2007 Junior Achievement—a nonprofit educational organization that provides hands-on business training programs to youths throughout the world—inducted Turner into its U.S. Business Hall of Fame. In 2008 Turner released his autobiography, 'Call Me Ted'.

Jai Ganesh · 2016-05-04 00:25:10

125. Roald Amundsen

Roald Amundsen, in full Roald Engelbregt Gravning Amundsen (born July 16, 1872, Borge, near Oslo, Norway—died June 18, 1928?, Arctic Ocean) Norwegian explorer who was the first to reach the South Pole, the first to make a ship voyage through the Northwest Passage, and one of the first to cross the Arctic by air. He was one of the greatest figures in the field of polar exploration.

Amundsen studied medicine for a while and then took to sea. In 1897 he sailed as first mate on the Belgica in a Belgian expedition that was the first to winter in the Antarctic. In 1903, with a crew of six on his 47-ton sloop Gjöa, Amundsen began his mission to sail through the Northwest Passage and around the northern Canadian coast. He reached Cape Colborne (in present-day Nunavut) in August 1905, completing his transit of the passage proper, before ice halted his westerly progress for the winter at Herschel Island in the Yukon the following month. Amundsen and his crew resumed the journey in August 1906 and were greeted with a heroes’ welcome when the expedition concluded in Nome, Alaska, later that month. This achievement whetted his appetite for the spectacular in polar exploration.

Amundsen’s next plan, to drift across the North Pole in Fridtjof Nansen’s old ship, the Fram, was affected by the news that the American explorer Robert E. Peary had reached the North Pole in April 1909, but he continued his preparations. When Amundsen left Norway in June 1910 no one but his brother knew that he was heading for the South Pole instead of the North. He sailed the Fram directly from the Madeira Islands to the Bay of Whales, Antarctica, along the Ross Sea. The base he set up there was 60 miles (100 km) closer to the pole than the Antarctic base of the English explorer Robert Falcon Scott, who was heading a rival expedition with the same goal. An experienced polar traveler, Amundsen prepared carefully for the coming journey, making a preliminary trip to deposit food supplies along the first part of his route to the pole and back. To transport his supplies, he used sled dogs, while Scott depended on Siberian ponies.

Amundsen set out with 4 companions, 52 dogs, and 4 sledges on October 19, 1911, and, after encountering good weather, arrived at the South Pole on December 14. The explorers recorded scientific data at the pole before beginning the return journey on December 17, and they safely reached their base at the Bay of Whales on January 25, 1912. Scott, in the meantime, had reached the South Pole on January 17, but on a difficult return journey he and all his men perished.

With funds resulting from his Antarctic adventure, Amundsen established a successful shipping business. He acquired a new ship, the Maud, and tried in 1918 to complete his old plan of drifting across the North Pole, but he was forced to abandon this scheme in favour of trying to reach the North Pole by airplane. In a flight (1925) with the American explorer Lincoln Ellsworth he arrived to within 150 miles (250 km) of the pole. In 1926, with Ellsworth and the Italian aeronautical engineer Umberto Nobile, he passed over the North Pole in a dirigible, crossing from Spitsbergen (now Svalbard), north of Norway, to Alaska. Disputes over the credit for the flight embittered his final years. In 1928 Amundsen lost his life in flying to rescue Nobile from a dirigible crash near Spitsbergen. Amundsen’s books include 'The South Pole' (1912) and, with Ellsworth, 'First Crossing of the Polar Sea' (1927).

Jai Ganesh · 2016-05-04 16:49:55

126. Daniel Bernoulli

Daniel Bernoulli, (born Feb. 8 [Jan. 29, Old Style], 1700, Groningen, Neth.—died March 17, 1782, Basel, Switz.) the most distinguished of the second generation of the Bernoulli family of Swiss mathematicians. He investigated not only mathematics but also such fields as medicine, biology, physiology, mechanics, physics, astronomy, and oceanography. Bernoulli’s theorem, which he derived, is named after him.

Daniel Bernoulli was the second son of Johann Bernoulli, who first taught him mathematics. After studying philosophy, logic, and medicine at the universities of Heidelberg, Strasbourg, and Basel, he received an M.D. degree (1721). In 1723–24 he wrote 'Exercitationes quaedam Mathematicae' on differential equations and the physics of flowing water, which won him a position at the influential Academy of Sciences in St. Petersburg, Russia. Bernoulli lectured there until 1732 in medicine, mechanics, and physics, and he researched the properties of vibrating and rotating bodies and contributed to probability theory. In that same year he returned to the University of Basel to accept the post in anatomy and botany. By then he was widely esteemed by scholars and also admired by the public throughout Europe.

Daniel’s reputation was established in 1738 with 'Hydrodynamica', in which he considered the properties of basic importance in fluid flow, particularly pressure, density, and velocity, and set forth their fundamental relationship. He put forward what is called Bernoulli’s principle, which states that the pressure in a fluid decreases as its velocity increases. He also established the basis for the kinetic theory of gases and heat by demonstrating that the impact of molecules on a surface would explain pressure and that, assuming the constant, random motion of molecules, pressure and motion increase with temperature. About 1738 his father published Hydraulica; this attempt by Johann to obtain priority for himself was another instance of his antagonism toward his son.

Between 1725 and 1749 Daniel won 10 prizes from the Paris Academy of Sciences for work on astronomy, gravity, tides, magnetism, ocean currents, and the behaviour of ships at sea. He also made substantial contributions in probability. He shared the 1735 prize for work on planetary orbits with his father, who, it is said, threw him out of the house for thus obtaining a prize he felt should be his alone. Daniel’s prizewinning papers reflected his success on the research frontiers of science and his ability to set forth clearly before an interested public the scientific problems of the day. In 1732 he accepted a post in botany and anatomy at Basel; in 1743, one in physiology; and in 1750, one in physics.

Jai Ganesh · 2016-05-05 16:39:35

127. Amerigo Vespucci

Amerigo Vespucci, (born 1454?, Florence, Italy—died 1512, Sevilla, Spain) merchant and explorer-navigator who took part in early voyages to the New World (1499–1500, 1501–02) and occupied the influential post of piloto mayor (“master navigator”) in Sevilla (1508–12). The name for the Americas is derived from his given name.

Early life

Vespucci was the son of Nastagio, a notary. As a boy Vespucci was given a humanistic education by his uncle Giorgio Antonio. In 1479 he accompanied another relation, sent by the famous Italian Medici family to be their spokesman to the king of France. On returning, Vespucci entered the “bank” of Lorenzo and Giovanni di Pierfrancesco de’ Medici and gained the confidence of his employers. At the end of 1491 their agent, Giannotto Berardi, appears to have been engaged partly in fitting out ships; and Vespucci was probably present when Christopher Columbus returned from his first expedition, which Berardi had assisted. Later Vespucci was to collaborate, still with Berardi, in the preparation of a ship for Columbus’s second expedition and of others for his third. When Berardi died, either at the end of 1495 or at the beginning of 1496, Vespucci became manager of the Sevilla agency.

Vespucci’s voyages

The period during which Vespucci made his voyages falls between 1497 and 1504. Two series of documents on his voyages are extant. The first series consists of a letter in the name of Vespucci from Lisbon, Portugal, dated September 4, 1504, written in Italian, perhaps to the gonfalonier (magistrate of a medieval Italian republic) Piero Soderini, and printed in Florence in 1505; and of two Latin versions of this letter, printed under the titles of “Quattuor Americi navigationes” and “Mundus Novus,” or “Epistola Alberici de Novo Mundo.” The second series consists of three private letters addressed to the Medici. In the first series of documents, four voyages by Vespucci are mentioned; in the second, only two. Until the 1930s the documents of the first series were considered from the point of view of the order of the four voyages. According to a theory of Alberto Magnaghi, on the contrary, these documents are to be regarded as the result of skillful manipulations, and the sole authentic papers would be the private letters, so that the verified voyages would be reduced to two. The question is fundamental for the evaluation of Vespucci’s work and has given rise to fierce controversy; attempts to reconcile the two series of documents cannot generally be considered successful.

The voyage completed by Vespucci between May 1499 and June 1500 as navigator of an expedition of four ships sent from Spain under the command of Alonso de Ojeda is certainly authentic. (This is the second expedition of the traditional series.) Since Vespucci took part as navigator, he certainly cannot have been inexperienced; but it does not seem possible that he had made a previous voyage (1497–98) in this area (i.e., around the Gulf of Mexico and the Atlantic coast from Florida to Chesapeake Bay), though this matter remains unresolved.

In the voyage of 1499–1500 Vespucci would seem to have left Ojeda after reaching the coast of what is now Guyana. Turning south, he is believed to have discovered the mouth of the Amazon River and to have gone as far as Cape St. Augustine (latitude about 6° S). On the way back he reached Trinidad, sighted the mouth of the Orinoco River, and then made for Haiti. Vespucci thought he had sailed along the coast of the extreme easterly peninsula of Asia, where Ptolemy, the geographer, believed the market of Cattigara to be; so he looked for the tip of this peninsula, calling it Cape Cattigara. He supposed that the ships, once past this point, emerged into the seas of southern Asia. As soon as he was back in Spain, he equipped a fresh expedition with the aim of reaching the Indian Ocean, the Gulf of the Ganges (modern Bay of Bengal), and the island of Taprobane or Ceylon (now Sri Lanka). But the Spanish government did not welcome his proposals, and at the end of 1500 Vespucci went into the service of Portugal.

Under Portuguese auspices Vespucci completed a second expedition, which set off from Lisbon on May 13, 1501. After a halt at the Cape Verde Islands, the expedition traveled southwestward and reached the coast of Brazil toward Cape St. Augustine. The remainder of the voyage is disputed, but Vespucci claimed to have continued southward, and he may have sighted (January 1502) Guanabara Bay (Rio de Janeiro’s bay) and sailed as far as the Río de la Plata, making Vespucci the first European to discover that estuary (Juan Díaz de Solís arrived there in 1516). The ships may have journeyed still farther south, along the coast of Patagonia (in present-day southern Argentina). The return route is unknown. Vespucci’s ships anchored at Lisbon on July 22, 1502.

Vespucci’s namesake and reputation

The voyage of 1501–02 is of fundamental importance in the history of geographic discovery in that Vespucci himself, and scholars as well, became convinced that the newly discovered lands were not part of Asia but a “New World.” In 1507 a humanist, Martin Waldseemüller, reprinted at Saint-Dié in Lorraine the “Quattuor Americi navigationes” (“Four Voyages of Amerigo”), preceded by a pamphlet of his own entitled “Cosmographiae introductio,” and he suggested that the newly discovered world be named “ab Americo Inventore…quasi Americi terram sive Americam” (“from Amerigo the discoverer…as if it were the land of Americus or America”). The proposal is perpetuated in a large planisphere of Waldseemüller’s, in which the name America appears for the first time, although applied only to South America. The suggestion caught on; the extension of the name to North America, however, came later. On the upper part of the map, with the hemisphere comprising the Old World, appears the picture of Ptolemy; on the part of the map with the New World hemisphere is the picture of Vespucci.

It is uncertain whether Vespucci took part in yet another expedition (1503–04) for the Portuguese government (it is said that he may have been with one under Gonzalo Coelho). In any case, this expedition contributed no fresh knowledge. Although Vespucci subsequently helped to prepare other expeditions, he never again joined one in person.

At the beginning of 1505 he was summoned to the court of Spain for a private consultation and, as a man of experience, was engaged to work for the famous Casa de Contratación de las Indias (Commercial House for the Indies), which had been founded two years before at Sevilla. In 1508 the house appointed him chief navigator, a post of great responsibility, which included the examination of the pilots’ and ships’ masters’ licenses for voyages. He also had to prepare the official map of newly discovered lands and of the routes to them (for the royal survey), interpreting and coordinating all data that the captains were obliged to furnish. Vespucci, who had obtained Spanish citizenship, held this position until his death. His widow, Maria Cerezo, was granted a pension in recognition of her husband’s great services.

Some scholars have held Vespucci to be a usurper of the merits of others. Yet, despite the possibly deceptive claims made by him or advanced on his behalf, he was a genuine pioneer of Atlantic exploration and a vivid contributor to the early travel literature of the New World.

Jai Ganesh · 2016-05-06 16:17:20

128. David Hilbert

David Hilbert, (born January 23, 1862, Königsberg, Prussia [now Kaliningrad, Russia]—died February 14, 1943, Göttingen, Germany) German mathematician who reduced geometry to a series of axioms and contributed substantially to the establishment of the formalistic foundations of mathematics. His work in 1909 on integral equations led to 20th-century research in functional analysis.

The first steps of Hilbert’s career occurred at the University of Königsberg, at which, in 1884, he finished his Inaugurel-dissertation (Ph.D.); he remained at Königsberg as a Privatdozent (lecturer, or assistant professor) in 1886–92, as an Extraordinarius (associate professor) in 1892–93, and as an Ordinarius in 1893–95. In 1892 he married Käthe Jerosch, and they had one child, Franz. In 1895 Hilbert accepted a professorship in mathematics at the University of Göttingen, at which he remained for the rest of his life.

The University of Göttingen had a flourishing tradition in mathematics, primarily as the result of the contributions of Carl Friedrich Gauss, Peter Gustav Lejeune Dirichlet, and Bernhard Riemann in the 19th century. During the first three decades of the 20th century this mathematical tradition achieved even greater eminence, largely because of Hilbert. The Mathematical Institute at Göttingen drew students and visitors from all over the world.

Hilbert’s intense interest in mathematical physics also contributed to the university’s reputation in physics. His colleague and friend, the mathematician Hermann Minkowski, aided in the new application of mathematics to physics until his untimely death in 1909. Three winners of the Nobel Prize for Physics—Max von Laue in 1914, James Franck in 1925, and Werner Heisenberg in 1932—spent significant parts of their careers at the University of Göttingen during Hilbert’s lifetime.

In a highly original way, Hilbert extensively modified the mathematics of invariants—the entities that are not altered during such geometric changes as rotation, dilation, and reflection. Hilbert proved the theorem of invariants—that all invariants can be expressed in terms of a finite number. In his Zahlbericht (“Commentary on Numbers”), a report on algebraic number theory published in 1897, he consolidated what was known in this subject and pointed the way to the developments that followed. In 1899 he published the Grundlagen der Geometrie (The Foundations of Geometry, 1902), which contained his definitive set of axioms for Euclidean geometry and a keen analysis of their significance. This popular book, which appeared in 10 editions, marked a turning point in the axiomatic treatment of geometry.

A substantial part of Hilbert’s fame rests on a list of 23 research problems he enunciated in 1900 at the International Mathematical Congress in Paris. In his address, “The Problems of Mathematics,” he surveyed nearly all the mathematics of his day and endeavoured to set forth the problems he thought would be significant for mathematicians in the 20th century. Many of the problems have since been solved, and each solution was a noted event. Of those that remain, however, one, in part, requires a solution to the Riemann hypothesis, which is usually considered to be the most important unsolved problem in mathematics (see number theory).

In 1905 the first award of the Wolfgang Bolyai prize of the Hungarian Academy of Sciences went to Henri Poincaré, but it was accompanied by a special citation for Hilbert.

In 1905 (and again from 1918) Hilbert attempted to lay a firm foundation for mathematics by proving consistency—that is, that finite steps of reasoning in logic could not lead to a contradiction. But in 1931 the Austrian–U.S. mathematician Kurt Gödel showed this goal to be unattainable: propositions may be formulated that are undecidable; thus, it cannot be known with certainty that mathematical axioms do not lead to contradictions. Nevertheless, the development of logic after Hilbert was different, for he established the formalistic foundations of mathematics.

Hilbert’s work in integral equations in about 1909 led directly to 20th-century research in functional analysis (the branch of mathematics in which functions are studied collectively). His work also established the basis for his work on infinite-dimensional space, later called Hilbert space, a concept that is useful in mathematical analysis and quantum mechanics. Making use of his results on integral equations, Hilbert contributed to the development of mathematical physics by his important memoirs on kinetic gas theory and the theory of radiations. In 1909 he proved the conjecture in number theory that for any n, all positive integers are sums of a certain fixed number of nth powers; for example,

, in which n = 2. In 1910 the second Bolyai award went to Hilbert alone and, appropriately, Poincaré wrote the glowing tribute.

The city of Königsberg in 1930, the year of his retirement from the University of Göttingen, made Hilbert an honorary citizen. For this occasion he prepared an address entitled “Naturerkennen und Logik” (“The Understanding of Nature and Logic”). The last six words of Hilbert’s address sum up his enthusiasm for mathematics and the devoted life he spent raising it to a new level: “Wir müssen wissen, wir werden wissen” (“We must know, we shall know”). In 1939 the first Mittag-Leffler prize of the Swedish Academy went jointly to Hilbert and the French mathematician Émile Picard.

The last decade of Hilbert’s life was darkened by the tragedy brought to himself and to so many of his students and colleagues by the Nazi regime.

Jai Ganesh · 2016-05-07 17:18:50

129. Georg Cantor, (born March 3, 1845, St. Petersburg, Russia—died Jan. 6, 1918, Halle, Ger.) German mathematician who founded set theory and introduced the mathematically meaningful concept of transfinite numbers, indefinitely large but distinct from one another.

Early life and training

Cantor’s parents were Danish. His artistic mother, a Roman Catholic, came from a family of musicians, and his father, a Protestant, was a prosperous merchant. When his father became ill in 1856, the family moved to Frankfurt. Cantor’s mathematical talents emerged prior to his 15th birthday while studying in private schools and at gymnasien at Darmstadt first and then at Wiesbaden; eventually, he overcame the objections of his father, who wanted him to become an engineer.

After briefly attending the University of Zürich, Cantor in 1863 transferred to the University of Berlin to specialize in physics, philosophy, and mathematics. There he was taught by the mathematicians Karl Theodor Weierstrass, whose specialization of analysis probably had the greatest influence on him; Ernst Eduard Kummer, in higher arithmetic; and Leopold Kronecker, a specialist on the theory of numbers who later opposed him. Following one semester at the University of Göttingen in 1866, Cantor wrote his doctoral thesis in 1867, In re mathematica ars propendi pluris facienda est quam solvendi (“In mathematics the art of asking questions is more valuable than solving problems”), on a question that Carl Friedrich Gauss had left unsettled in his Disquisitiones Arithmeticae (1801). After a brief teaching assignment in a Berlin girls’ school, Cantor joined the faculty at the University of Halle, where he remained for the rest of his life, first as lecturer (paid by fees only) in 1869, then assistant professor in 1872, and full professor in 1879.

In a series of 10 papers from 1869 to 1873, Cantor dealt first with the theory of numbers; this article reflected his own fascination with the subject, his studies of Gauss, and the influence of Kronecker. On the suggestion of Heinrich Eduard Heine, a colleague at Halle who recognized his ability, Cantor then turned to the theory of trigonometric series, in which he extended the concept of real numbers. Starting from the work on trigonometric series and on the function of a complex variable done by the German mathematician Bernhard Riemann in 1854, Cantor in 1870 showed that such a function can be represented in only one way by a trigonometric series. Consideration of the collection of numbers (points) that would not conflict with such a representation led him, first, in 1872, to define irrational numbers in terms of convergent sequences of rational numbers (quotients of integers) and then to begin his major lifework, the theory of sets and the concept of transfinite numbers.

Set theory.

An important exchange of letters with Richard Dedekind, mathematician at the Brunswick Technical Institute, who was his lifelong friend and colleague, marked the beginning of Cantor’s ideas on the theory of sets. Both agreed that a set, whether finite or infinite, is a collection of objects (e.g., the integers, {0, ±1, ±2 . . .}) that share a particular property while each object retains its own individuality. But when Cantor applied the device of the one-to-one correspondence (e.g., {a, b, c} to {1, 2, 3}) to study the characteristics of sets, he quickly saw that they differed in the extent of their membership, even among infinite sets. (A set is infinite if one of its parts, or subsets, has as many objects as itself.) His method soon produced surprising results.

In 1873 Cantor demonstrated that the rational numbers, though infinite, are countable (or denumerable) because they may be placed in a one-to-one correspondence with the natural numbers (i.e., the integers, as 1, 2, 3, . . .). He showed that the set (or aggregate) of real numbers (composed of irrational and rational numbers) was infinite and uncountable. Even more paradoxically, he proved that the set of all algebraic numbers contains as many components as the set of all integers and that transcendental numbers (those that are not algebraic, as π), which are a subset of the irrationals, are uncountable and are therefore more numerous than integers, which must be conceived as infinite.

But Cantor’s paper, in which he first put forward these results, was refused for publication in Crelle’s Journal by one of its referees, Kronecker, who henceforth vehemently opposed his work. On Dedekind’s intervention, however, it was published in 1874 as “Über eine Eigenschaft des Inbegriffes aller reellen algebraischen Zahlen” (“On a Characteristic Property of All Real Algebraic Numbers”).

While honeymooning the same year with his bride, Vally Guttman, at Interlaken, Switz., Cantor met Dedekind, who gave a sympathetic hearing to his new theory. Cantor’s salary was low, but the estate of his father, who died in 1863, enabled him to build a house for his wife and five children. Many of his papers were published in Sweden in the new journal Acta Mathematica, edited and founded by Gösta Mittag-Leffler, one of the first persons to recognize his ability.

Cantor’s theory became a whole new subject of research concerning the mathematics of the infinite (e.g., an endless series, as 1, 2, 3, . . . , and even more complicated sets), and his theory was heavily dependent on the device of the one-to-one correspondence. In thus developing new ways of asking questions concerning continuity and infinity, Cantor quickly became controversial. When he argued that infinite numbers had an actual existence, he drew on ancient and medieval philosophy concerning the “actual” and “potential” infinite and also on the early religious training given him by his parents. In his book on sets, Grundlagen einer allgemeinen Mannigfaltigkeitslehre (“Foundations of a General Theory of Aggregates”), Cantor in 1883 allied his theory with Platonic metaphysics. By contrast, Kronecker, who held that only the integers “exist” (“God made the integers, and all the rest is the work of man”), for many years heatedly rejected his reasoning and blocked his appointment to the faculty at the University of Berlin.

Transfinite numbers

In 1895–97 Cantor fully propounded his view of continuity and the infinite, including infinite ordinals and cardinals, in his best known work, Beiträge zur Begründung der transfiniten Mengelehre (published in English under the title Contributions to the Founding of the Theory of Transfinite Numbers, 1915). This work contains his conception of transfinite numbers, to which he was led by his demonstration that an infinite set may be placed in a one-to-one correspondence with one of its subsets. By the smallest transfinite cardinal number he meant the cardinal number of any set that can be placed in one-to-one correspondence with the positive integers. This transfinite number he referred to as aleph-null. Larger transfinite cardinal numbers were denoted by aleph-one, aleph-two, . . . . He then developed an arithmetic of transfinite numbers that was analogous to finite arithmetic. Thus, he further enriched the concept of infinity. The opposition he faced and the length of time before his ideas were fully assimilated represented in part the difficulties of mathematicians in reassessing the ancient question: “What is a number?” Cantor demonstrated that the set of points on a line possessed a higher cardinal number than aleph-null. This led to the famous problem of the continuum hypothesis, namely, that there are no cardinal numbers between aleph-null and the cardinal number of the points on a line. This problem has, in the first and second halves of the 20th century, been of great interest to the mathematical world and was studied by many mathematicians, including the Czech-Austrian-American Kurt Gödel and the American Paul J. Cohen.

Although mental illness, beginning about 1884, afflicted the last years of his life, Cantor remained actively at work. In 1897 he helped to convene in Zürich the first international congress of mathematics. Partly because he had been opposed by Kronecker, he often sympathized with young, aspiring mathematicians and sought to find ways to ensure that they would not suffer as he had because of entrenched faculty members who felt threatened by new ideas. At the turn of the century, his work was fully recognized as fundamental to the development of function theory, of analysis, and of topology. Moreover, his work stimulated further development of both the intuitionist and the formalist schools of thought in the logical foundations of mathematics; it has substantially altered mathematical education in the United States and is often associated with the “new mathematics.”

Jai Ganesh · 2016-05-08 00:14:03

130. Wilhelm Ostwald, in full Friedrich Wilhelm Ostwald (born Sept. 2, 1853, Riga, Latvia, Russian Empire—died April 4, 1932, near Leipzig, Ger.) Russian-German chemist and philosopher who was instrumental in establishing physical chemistry as an acknowledged branch of chemistry. He was awarded the 1909 Nobel Prize for Chemistry for his work on catalysis, chemical equilibria, and chemical reaction velocities.

Early life and education

Ostwald was the second son of Gottfried Ostwald, a master cooper, and Elisabeth Leuckel, both descendants of German immigrants. After his early education in Riga, he enrolled in 1872 at the University of Dorpat (now Tartu, Est.), where he studied chemistry under Carl Schmidt and received a candidate’s degree (1875), a master’s degree (1876), and a doctorate (1878).

In 1880 Ostwald married Helene von Reyher. They had two daughters and three sons, of whom Wolfgang Ostwald became a famous colloid chemist. After their move to Leipzig, the Ostwalds became German citizens in 1888.

Scientific career

In 1881 Ostwald was appointed a full professor of chemistry at the Riga Polytechnic Institute. In 1887 he accepted the chair in physical chemistry at the University of Leipzig, from which he retired in 1906. By the time he started his scientific career, chemistry, particularly in Germany, was dominated by synthetic organic chemistry, which was primarily concerned with investigating what products can be produced from chemical compounds. Ostwald recognized the lack of a more profound and quantitative understanding of general issues of chemistry, such as the selective forces (chemical affinities or activities) in chemical reactions, which he sought to achieve by applying physical measurements and mathematical reasoning. To that end, in 1875 he began studying the equilibrium point in an aqueous solution in which two acids compete to form an acid-base reaction with one base. Because chemical analysis would have changed the equilibria, he skillfully adapted the measurement of physical properties, such as volume, refractive index, and electrical conductivity, to indirectly analyze the reactions. The idea was not completely new, as the Danish chemist Julius Thomsen had already studied the heat of such reactions. Ostwald could, however, also draw on the important law of mass action, which had been recently proposed by the Norwegian chemists Cato Guldberg and Peter Waagey, for analysis of his experimental results. Ostwald extended and generalized such approaches, adapting physical measurements to issues of chemical dynamics, to create a program not only of his own chemical work but also of a new school of physical chemistry.

In 1884 Ostwald received the doctoral thesis of Swedish chemist Svante Arrhenius on the electrical conductivity of solutions, which contained the bold claim that salts, acids, and bases dissociate into electrically charged ions when dissolved in water. The dissociation theory eventually became a backbone of the new school of physical chemistry, whose members were initially known as the “Ionists” and who soon counted Arrhenius himself among their members. Ostwald immediately recognized that if all acids contained the same active ion, then the differing chemical activities of various acids simply would be due to the concentration of active ions in each—and the concentration of active ions in turn would be dependent on the differing degrees of dissociation of the acids. In addition, if the law of mass action was applied to the dissociation reaction, a simple mathematical relation could be derived between the degree of dissociation (α), the concentration of the acid (c), and an equilibrium constant specific for each acid (k):

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This is Ostwald’s famous dissolution law (1888), which he tested by measuring the electrical conductivities of more than 200 organic acids, thereby substantiating the dissociation theory.

At the same time, the Dutch chemist Jacobus Henricus van ’t Hoff, who would join Ostwald and Arrhenius to form the “triumvirate” of the new physical chemistry school, suggested his theory of osmosis, according to which the osmotic pressure of solutions depends on the concentration of dissociated ions, in analogy to the pressure relationship obeyed by a perfect gas. Putting his theory on general thermodynamic grounds, van ’t Hoff also derived Raoult’s laws of vapour pressure, which assert that adding a solute to a liquid lowers its freezing point and raises its boiling point because of a reduction in the solution’s vapour pressure. (For instance, seawater has a lower freezing point and a higher boiling point than fresh water.) Through the combination of the triumvirate’s work, the new physical chemistry grew to a comprehensive theory of solutions based on both thermodynamics and dissociation theory.

Ostwald was especially successful in systematizing the subject of physical chemistry, applying it to other fields, and organizing a school. This was particularly important, as most chemists rejected the dissociation theory on partly justified grounds, such that convincing them required both concessions about its restricted validity and proofs of its broad usefulness. In various textbooks on general, inorganic, and analytical chemistry, Ostwald presented the new ideas not only in a comprehensive form as a new branch of chemistry but also as an extremely fruitful approach to classical issues. He particularly revolutionized analytical chemistry through solution theory and his theory of indicators. His Zeitschrift für physikalische Chemie (“Journal for Physical Chemistry”), founded in 1887, rapidly established itself as the standard journal in the field. Furthermore, the Leipzig Institute of Physical Chemistry attracted students and researchers from around the world. Educated in both the new ideas and experimental skills, numerous students of Ostwald later became professors of physical chemistry in many countries.

Ostwald’s later work on catalysis originated from early attempts at taking reaction velocities as a measure of chemical activity. As that turned out to be wrong on thermodynamic grounds, he broadly investigated temporal aspects of chemical reactions and provided a systematic conception of the field. He first recognized catalysis as the change of reaction velocity by a foreign compound, which allowed him to measure catalytic activities. He distinguished catalysis from triggering and from autocatalysis, which he considered essential to biological systems. His most famous contribution to applied chemistry was on catalytic oxidation of ammonia to nitric acid, a patented process that is still used in the industrial production of fertilizers.
Other notable activities

By the late 1880s, Ostwald’s interests had begun to include cultural and philosophical aspects of science. In 1889 he started republishing famous historical science papers in his series Klassiker der exakten Wissenschaften (“Classics of the Exact Sciences”), with more than 40 books published during the first four years. The history of chemistry, already part of his textbooks for educational reasons, became a subject of its own in many further books. He also published a volume on natural philosophy, derived from a series of lectures (1905–06) he had given as the first exchange professor at Harvard University in the United States. He was particularly interested in general laws of scientific progress, psychological characteristics of great scientists, and conditions for scientific creativity.

The more Ostwald became convinced that thermodynamics is the fundamental theory of science—for which he saw evidence in the pioneering works of the American physicist Josiah Willard Gibbs and others—the more he engaged in natural philosophy. Two aspects may roughly characterize his philosophy. First, he asserted the primacy of energy over matter (matter being only a manifestation of energy) in opposition to widespread scientific materialism. Ostwald reformulated older concepts of dynamism dating back to the 17th-century German polymath Gottfried Leibniz with the principles of thermodynamics to form a new metaphysical interpretation of the world that he named “energetics.” Second, he asserted a form of positivism in the sense of rejecting theoretical concepts that are not strictly founded on empirical grounds. Although energetics found few adherents, the latter position found many contemporary proponents, such as the physicist-philosophers Ernst Mach in Austria and Pierre Duhem in France. As a consequence of his beliefs, for some 15 years Ostwald rejected atomism and was heavily involved in philosophical debates with his atomist colleagues, such as the Austrian physicist Ludwig Boltzmann, before he acknowledged the growing experimental evidence for the atomic hypothesis in 1909.

Ostwald was quick to enlarge his energetics, incorporating sociology, psychology, and ethics. Beyond academic interest, he made it an “energetic imperative” of his own life: “Do not squander energy—utilize it!” Since Ostwald had strong utilitarian ideas of science, he considered every obstacle to the progress of science as squandering of “social energy.” Thus, after his early retirement in 1906 from the University of Leipzig, he became an enthusiastic reformer in educational and organizational matters of science on the national and international level. Ostwald was active in numerous academies, learned societies, and international movements, such as for the standardization of scientific documentation and the establishment of a “universal” artificial language (he contributed to Ido, a derivative of Esperanto). Moreover, he considered that both war and traditional religion squandered energy, so he committed himself to the international peace movement and served as president of the Deutscher Monistenbund, a scientistic quasi-religion founded by the German zoologist and evolutionary proponent Ernst Haeckel.
Later years

Ostwald colour system

After formally retiring in 1906, Ostwald continued as a freelance researcher at his private estate near Leipzig, where he had assembled a large library and a laboratory. He started another scientific career in colour theory in his 60s, supplementing his lifelong passion for painting. Once more he applied the multilevel approach characteristic of his earlier work. He developed instruments for measuring colours, elaborated a sophisticated classification of colours in order to derive mathematical laws of harmony, produced specimens in his chemical laboratory, founded a factory for paint boxes, wrote several textbooks on colour theory and its history, and was active in reforms of artistic education. After a short period of suffering from bladder and prostate troubles, Ostwald died in a Leipzig hospital and was buried at his private estate.

Ostwald was a man of science in the broadest sense and an extremely prolific writer. He was the editor of several scientific and philosophical journals, and he wrote 45 books and many booklets, about 500 scientific papers, some 5,000 reviews, and more than 10,000 letters.

Last edited by Jai Ganesh (2016-05-08 00:27:20)

Jai Ganesh · 2016-05-08 16:17:33

131. Sir Henry Bessemer, (born Jan. 19, 1813, Charlton, Hertfordshire, Eng.—died March 15, 1898, London) inventor and engineer who developed the first process for manufacturing steel inexpensively (1856), leading to the development of the Bessemer converter. He was knighted in 1879.

Bessemer was the son of an engineer and typefounder. He early showed considerable mechanical skill and inventive powers. After the invention of movable stamps for dating deeds and other government documents and the improvement of a typesetting machine, he went to the manufacture of “gold” powder from brass for use in paints. The florid decoration of the time demanded great quantities of such material, and Bessemer’s secret process soon brought him great wealth.

He developed other inventions, notably sugarcane-crushing machinery of advanced design, but he was soon devoted to metallurgy. In his time there were but two iron-based construction materials: cast iron made by the treatment of iron ore with coke in the blast furnace and wrought iron made from cast iron in primitive furnaces by the laborious manual process of “puddling” (stirring the melted iron to remove carbon and raking off the slag). Cast iron was excellent for load-bearing purposes, such as columns or bridge piers, and for engine parts, but for girders and other spans, and particularly for rails, only wrought iron was suitable. Puddling removed carbon, which makes cast iron brittle, and produced a material that could be rolled or forged, but only in “blooms,” or large lumps of 100–200 pounds, and that was full of slag. The blooms had to be laboriously forged together by steam hammers before they could be rolled to any useful length or shape. The only material known as steel was made by adding carbon to pure forms of wrought iron, also by slow and discontinuous methods; the material was hard, would take an edge, and was used almost entirely for cutting tools.

During the Crimean War, Bessemer invented an elongated artillery shell that was rotated by the powder gases. The French authorities with whom he was negotiating, however, pointed out that their cast-iron cannon would not be strong enough for this kind of shell. He thereupon attempted to produce a stronger cast iron. In his experiments he discovered that the excess oxygen in the hot gases of his furnace appeared to have removed the carbon from the iron pigs that were being preheated—much as the carbon is removed in a puddling furnace—leaving a skin of pure iron. Bessemer then found that blowing air through melted cast iron not only purified the iron but also heated it further, allowing the purified iron to be easily poured. This heating effect is caused by the reaction of oxygen with the carbon and silicon in the iron. Utilizing these new techniques, which later became known as the Bessemer process, he was soon able to produce large, slag-free ingots as workable as any wrought-iron bloom, and far larger; he invented the tilting converter into which molten pig iron could be poured before air was blown in from below. Eventually, with the aid of an iron-manganese alloy, which was developed at that time by Robert Forester Mushet, Bessemer also found how to remove excess oxygen from the decarburized iron.

His announcement of the process in 1856 before the British Association for the Advancement of Science in Cheltenham, Gloucestershire, brought many ironmasters to his door, and many licenses were granted. Very soon, however, it became clear that two elements harmful to iron, phosphorus and sulfur, were not removed by the process—or at least not by the fireclay lining of Bessemer’s converter. It was not until about 1877 that the British metallurgist Sidney Gilchrist Thomas developed a lining that removed phosphorus and made possible the use of phosphoric ores of the Continent.

Bessemer had, unknown to himself, been using phosphorus-free iron, but the ironmasters were not so lucky. Their iron was perfectly satisfactory for the puddling process, in which phosphorus is removed because the temperatures are lower, but it could not be used in the Bessemer process. Bessemer was forced to call in his licenses and find a phosphorus-free source of iron in northwestern England; thus he was able to enter the steel market on his own. Once the phosphorus problem was recognized and solved, he became a licensor once again, and vast profits flowed in. It became clear that “mild steel”—as it was known to distinguish it from the hard tool steels—could more clearly and reliably be used in place of wrought iron for ship plate, girders, sheet, rods, wire, rivets, and other items. The invention of the open-hearth (Siemens-Martin) process in the late 1860s eventually outstripped that of the Bessemer process. This has now yielded place, in great measure, to oxygen steelmaking, which is a further development and refinement of the Bessemer process.

In his later years—the process had not become a clear success until he was nearing 70—Bessemer continued to invent and make discoveries. The solar furnace he built was more than a successful toy; he designed and built an astronomical telescope for his own amusement; and he developed a set of machines for polishing diamonds that helped to reestablish that trade in London.

Apart from his knighthood, he received many honours, such as the Fellowship of the Royal Society. Bessemer’s 'An Autobiography' (1905), with a concluding chapter by his son, Henry Bessemer, is the only comprehensive biography and the source of most material written about him since.

Jai Ganesh · 2016-05-09 23:43:52

132. Anders Celsius

Celsius’ father was professor of astronomy at the University of Uppsala, and his son early followed in his footsteps. He studied astronomy, mathematics, and experimental physics; and in 1725 he became secretary of the Uppsala Scientific Society. After teaching at the university for several years as professor of mathematics, in April 1730 Celsius was appointed professor of astronomy. From 1732 to 1736 he traveled extensively in other countries to broaden his knowledge. He visited astronomers and observatories in Berlin and Nuremburg; in the latter city he published a collection of observations of the aurora borealis (1733). He went on to Italy, and then to Paris; there he made the acquaintance of Maupertuis, who was preparing an expedition to measure a meridian in the north in hopes of verifying the Newtonian theory that the earth is flattened at the poles and disproving the contrary Cartesian view, Celsius joined the Maupertuis expedition, and in 1735 he went to London to secure needed instruments. The next year he followed the French expedition to Torneå, in northern Sweden (now Tornio, Finland). During 1736–1737, in his capacity as astronomer, he helped with the planned meridian measurement; and Newton’s theory was confirmed. He was active in the controversy that later developed over what Maupertuis had done and fired a literary broadside, De observationibus pro figura telluris determinanda (1738), against Jacques Cassini.

On his subsequent return to Uppsala, Celsius breathed new life into the teaching of astronomy at the university. In 1742 he moved into the newly completed astronomical observatory, which had been under construction for several years and was the first modern installation of its kind in Sweden.

Although he died young, Celsius lived long enough to make important contributions in several fields. As an astronomer he was primarily an observer. Using a purely photometric method (filtering light through glass plates), he attempted to determine the magnitude of the stars in Aries (De constellatione Arietis, 1740). During the lively debate over the falling level of the Baltic, he wrote a paper on the subject based on exact experiments, “Anmärkning om vatnets fö -minskande” (1743). Today Celsius is best known in connection with a thermometer scale. Although a 100-degree scale had been in use earlier, it was Celsius’s famous observations concerning the two “constant degrees” on a thermometer, “Observationer om twänne beständiga grader på en thermometer” (1742), that led to its general acceptance. As the “constant degrees,” or fixed points, he chose the freezing and boiling points of water, calling the boiling point zero and the freezing point 100. The present system, with the scale reversed, introduced in 1747 at the Uppsala observatory, was long known as the “Swedish thermometer.” Not until around 1800 did people start referring to it as the Celsius thermometer.

Jai Ganesh · 2016-05-11 23:07:30

133. Joseph-Michel and Jacques-Étienne Montgolfier, also called the Montgolfier brothers (respectively, born Aug. 26, 1740, Annonay, France—died June 26, 1810, Balaruc-les-Bains; born Jan. 6, 1745, Annonay, France—died Aug. 2, 1799, enroute from Lyon to Annonay) French brothers who were pioneer developers of the hot-air balloon and who conducted the first untethered flights. Modifications and improvements of the basic Montgolfier design were incorporated in the construction of larger balloons that, in later years, opened the way to exploration of the upper atmosphere.

Joseph and Étienne were 2 of the 16 children of Pierre Montgolfier, whose prosperous paper factories in the small town of Vidalon, near Annonay, in southern France, ensured the financial support of their balloon experiments. While carrying on their father’s paper business, they maintained their interest in scientific experimentation.

In 1782 they discovered that heated air, when collected inside a large lightweight paper or fabric bag, caused the bag to rise into the air. The Montgolfiers made the first public demonstration of this discovery on June 4, 1783, at the marketplace in Annonay. They filled their balloon with heated air by burning straw and wool under the opening at the bottom of the bag. The balloon rose into the air about 3,000 feet (1,000 metres), remained there some 10 minutes, and then settled to the ground more than a mile and a half from where it rose. The Montgolfiers traveled to Paris and then to Versailles, where they repeated the experiment with a larger balloon on Sept. 19, 1783, sending a sheep, a rooster, and a duck aloft as passengers. The balloon floated for about 8 minutes and landed safely about 2 miles (3.2 kilometres) from the launch site. On Nov. 21, 1783, the first manned untethered flight took place in a Montgolfier balloon with Pilatre de Rozier and François Laurent, marquis d’Arlandes, as passengers. The balloon sailed over Paris for 5.5 miles (9 kilometres) in about 25 minutes.

The two brothers were honoured by the French Académie des Sciences. They published books on aeronautics and continued their scientific careers. Joseph invented a calorimeter and the hydraulic ram, and Étienne developed a process for manufacturing vellum.

Last edited by Jai Ganesh (2016-05-11 23:08:49)

Jai Ganesh · 2016-05-14 00:57:28

134. William Caxton

William Caxton, (born c. 1422, Kent, England—died 1491, London) the first English printer, who, as a translator and publisher, exerted an important influence on English literature.

In 1438 he was apprenticed to Robert Large, a rich mercer, who in the following year became lord mayor of London. Large died in 1441, and Caxton moved to Brugge, the centre of the European wool trade; during the next 30 years he became an increasingly prosperous and influential member of the English trading community in Flanders and Holland. In 1463 he took up duties as “Governor of the English Nation of Merchant Adventurers” in the Low Countries—a post of real authority over his fellow merchants. Sometime in 1470 he ceased to be governor and entered the service of Margaret, duchess of Burgundy, possibly as her financial adviser.

In that period Caxton’s interests were turning to literature. In March 1469 he had begun to translate Raoul Le Fèvre’s Recueil des histoires de Troye, which he laid aside and did not finish until September 19, 1471. In Cologne, where he lived from 1470 to the end of 1472, he learned printing. In the epilogue of Book III of the completed translation, entitled The Recuyell of the Historyes of Troye, he tells how his “pen became worn, his hand weary, his eye dimmed” with copying the book; so he “practised and learnt” at great personal cost how to print it. He set up a press in Brugge about 1474, and the Recuyell, the first book printed in English, was published there in 1475. Caxton’s translation from the French of The Game and Playe of the Chesse (in which chess is treated as an allegory of life) was published in 1476. Caxton printed two or three other works in Brugge in French, but toward the end of 1476 he returned to England and established his press at Westminster. From then on he devoted himself to writing and printing. The first dated book printed in English, Dictes and Sayenges of the Phylosophers, appeared on November 18, 1477.

Although a pioneer of printing in England, Caxton showed no great typographical originality and produced no books of remarkable beauty. Kings, nobles, and rich merchants were Caxton’s patrons and sometimes commissioned special books. His varied output—including books of chivalric romance, conduct, morality, history, and philosophy and an encyclopaedia, The Myrrour of the Worlde (1481), the first illustrated English book—shows that he catered also to a general public. The large number of service books and devotional works published by Caxton were the staple reading of most literate persons. He also printed nearly all the English literature available to him in his time: Canterbury Tales (1478? and 1484?) and other poems by Chaucer, John Gower’s Confessio amantis (1483), Sir Thomas Malory’s Morte Darthur (1485), and much of John Lydgate. Caxton translated 24 books, some of them immensely long. By the time of his death, he had published about 100 items of various kinds.

Jai Ganesh · 2016-05-15 16:53:58

135. Henry Briggs

Henry Briggs (February 1561 – 26 January 1630) was an English mathematician notable for changing the original logarithms invented by John Napier into common (base 10) logarithms, which are sometimes known as Briggsian logarithms in his honour.

Briggs was a committed puritan and an influential professor in his time.

Personal life

He was born at Warleywood, near Halifax, in Yorkshire, England. After studying Latin and Greek at a local grammar school, he entered St John's College, Cambridge, in 1577, and graduated in 1581. In 1588, he was elected of Fellow of St. John's. In 1592 he was made reader of the physical lecture founded by Thomas Linacre; he would also read some of the mathematical lectures as well. During this period, he took an interest in navigation and astronomy, collaborating with Edward Wright.

In 1596, he became first professor of Geometry in the recently founded Gresham College, London; where he taught geometry, astronomy and navigation. He would lecture there for nearly 23 years, and would make Gresham college a center of English mathematics, from which he would notably support the new ideas of Johannes Kepler.

He was a friend of Christopher Heydon, the writer on astrology, though Briggs himself rejected astrology for religious reasons.

At this time, Briggs obtained a copy of Mirifici Logarithmorum Canonis Descriptio, in which Napier introduced the idea of logarithms. Napier's formulation was awkward to work with, but the book fired Briggs' imagination - in his lectures at Gresham College he proposed the idea of base 10 logarithms in which the logarithm of 10 would be 1; and soon afterwards he wrote to the inventor on the subject. Briggs was active in many areas, and his advice in astronomy, surveying, navigation, and other activities like mining was frequently sought. Briggs in 1619 invested in the London Company, and he had two sons: Henry, who later emigrated to Virginia, and Thomas, who remained in England. The lunar crater Briggs is named in his honour.

Mathematical contribution

A page from Henry Briggs' 1617 Logarithmorum Chilias Prima showing the base-10 (common) logarithm of the integers 0 to 67 to fourteen decimal places.

In 1616 Briggs visited Napier at Edinburgh in order to discuss the suggested change to Napier's logarithms. The following year he again visited for a similar purpose. During these conferences the alteration proposed by Briggs was agreed upon; and on his return from his second visit to Edinburgh, in 1617, he published the first chiliad of his logarithms.

In 1619 he was appointed Savilian professor of geometry at Oxford, and resigned his professorship of Gresham College in July 1620. Soon after his settlement at Oxford he was incorporated master of arts.

In 1622 he published a small tract on the Northwest Passage to the South Seas, through the Continent of Virginia and Hudson Bay. The tract is notorious today as the origin of the cartographic myth of California as an Island. In it Briggs stated he had seen a map that had been brought from Holland that showed California Island. Briggs' tract was republished three years later (1625) in Pvrchas His Pilgrimes (vol 3, p848).

In 1624 his Arithmetica Logarithmica, in folio, a work containing the logarithms of thirty thousand natural numbers to fourteen decimal places (1-20,000 and 90,001 to 100,000). This table was later extended by Adriaan Vlacq, but to 10 places, and by Alexander John Thompson to 20 places in 1952. Briggs was one of the first to use finite-difference methods to compute tables of functions.

He also completed a table of logarithmic sines and tangents for the hundredth part of every degree to fourteen decimal places, with a table of natural sines to fifteen places, and the tangents and secants for the same to ten places; all of which were printed at Gouda in 1631 and published in 1633 under the title of Trigonometria Britannica; this work was probably a successor to his 1617 Logarithmorum Chilias Prima ("The First Thousand Logarithms"), which gave a brief account of logarithms and a long table of the first 1000 integers calculated to the 14th decimal place.

Briggs discovered, in a somewhat concealed form and without proof, the binomial theorem. English translations of Briggs's Arithmetica and the first part of his Trigonometria Britannica are available on the web.

Briggs was buried in the chapel of Merton College, Oxford. Dr Smith, in his Lives of the Gresham Professors, characterizes him as a man of great probity, a condemner of riches, and contented with his own station, preferring a studious retirement to all the splendid circumstances of life.

Jai Ganesh · 2016-05-17 00:59:28

136. Faxian

Faxian (337 – c. 422) was a Chinese Buddhist monk who travelled by foot from China to India, visiting many sacred Buddhist sites in what are now Xinjiang, Pakistan, India, Nepal, Bangladesh and Sri Lanka between 399-412 to acquire Buddhist texts. His journey is described in his important travelogue, A Record of Buddhist Kingdoms, Being an Account by the Chinese Monk Fa-Xian of his Travels in India and Ceylon in Search of the Buddhist Books of Discipline. Antiquated transliterations of his name include Fa-Hien and Fa-hsien.

Biography

Faxian visited India in the early fifth century. He is said to have walked all the way from China across icy desert and rugged mountain passes. He entered India from the northwest and reached Pataliputra. He took back with him Buddhist texts and images sacred to Buddhism.

Faxian's visit to India occurred during the reign of Chandragupta II. He is also renowned for his pilgrimage to Lumbini, the birthplace of Gautama Buddha (modern Nepal). Faxian claimed that demons and dragons were the original inhabitants of Sri Lanka.

On Faxian's way back to China, after a two-year stay in Ceylon, a violent storm drove his ship onto an island, probably Java. After five months there, Faxian took another ship for southern China; but, again, it was blown off course and he ended up landing at Mount Lao in what is now Shandong in northern China, 30 kilometres (19 mi) east of the city of Qingdao. He spent the rest of his life translating and editing the scriptures he had collected.

Faxian wrote a book on his travels, filled with accounts of early Buddhism, and the geography and history of numerous countries along the Silk Roads as they were, at the turn of the 5th century CE.

Translation of Faxian's work

The following is from the introduction to a translation of Faxian's work by James Legge:

Nothing of great importance is known about Fa-hien in addition to what may be gathered from his own record of his travels. I have read the accounts of him in the Memoirs of Eminent Monks, compiled in A.D. 519, and a later work, the Memoirs of Marvellous Monks, by the third emperor of the Ming dynasty (A.D. 1403-1424), which, however, is nearly all borrowed from the other; and all in them that has an appearance of verisimilitude can be brought within brief compass

Faxian´s route through India

His surname, they tell us, was Kung, and he was a native of Wu-yang in P’ing-Yang, which is still the name of a large department in Shan-hsi. He had three brothers older than himself; but when they all died before shedding their first teeth, his father devoted him to the service of the Buddhist society, and had him entered as a Sramanera, still keeping him at home in the family. The little fellow fell dangerously ill, and the father sent him to the monastery, where he soon got well and refused to return to his parents.

When he was ten years old, his father died; and an uncle, considering the widowed solitariness and helplessness of the mother, urged him to renounce the monastic life, and return to her, but the boy replied, "I did not quit the family in compliance with my father’s wishes, but because I wished to be far from the dust and vulgar ways of life. This is why I chose monkhood." The uncle approved of his words and gave over urging him. When his mother also died, it appeared how great had been the affection for her of his fine nature; but after her burial he returned to the monastery.

On one occasion he was cutting rice with a score or two of his fellow-disciples, when some hungry thieves came upon them to take away their grain by force. The other Sramaneras all fled, but our young hero stood his ground, and said to the thieves, "If you must have the grain, take what you please. But, Sirs, it was your former neglect of charity which brought you to your present state of destitution; and now, again, you wish to rob others. I am afraid that in the coming ages you will have still greater poverty and distress;—I am sorry for you beforehand." With these words he followed his companions into the monastery, while the thieves left the grain and went away, all the monks, of whom there were several hundred, doing homage to his conduct and courage.

When he had finished his noviciate and taken on him the obligations of the full Buddhist orders, his earnest courage, clear intelligence, and strict regulation of his demeanour were conspicuous; and soon after, he undertook his journey to India in search of complete copies of the [Vinaya-pitaka]. What follows this is merely an account of his travels in India and return to China by sea, condensed from his own narrative, with the addition of some marvelous incidents that happened to him, on his visit to the Vulture Peak near Rajagriha.

It is said in the end that after his return to China, he went to the capital (evidently Nanking), and there, along with the Indian Sramana Buddha-bhadra, executed translations of some of the works which he had obtained in India; and that before he had done all that he wished to do in this way, he removed to King-chow (in the present Hoo-pih), and died in the monastery of Sin, at the age of eighty-eight, to the great sorrow of all who knew him. It is added that there is another larger work giving an account of his travels in various countries.

Such is all the information given about our author, beyond what he himself has told us. Fa-hien was his clerical name, and means "Illustrious in the Law," or "Illustrious master of the Law." The Shih which often precedes it is an abbreviation of the name of Buddha as Sakyamuni, "the Sakya, mighty in Love, dwelling in Seclusion and Silence," and may be taken as equivalent to Buddhist. It is sometimes said to have belonged to "the eastern Tsin dynasty" (A.D. 317-419), and sometimes to "the Sung," that is, the Sung dynasty of the House of Liu (A.D. 420-478). If he became a full monk at the age.... of twenty, and went to India when he was twenty-five, his long life may have been divided pretty equally between the two dynasties.

Fa%20Hien.jpg

Jai Ganesh · 2016-05-19 01:06:13

137. Xuanzang

Xuanzang, Wade-Giles romanization Hsüan-tsang, original name Chen Yi, honorary epithet San-tsang, also called Muchatipo, Sanskrit Mokshadeva, or Yuanzang (born 602, Goushi, Luozhou, now Yanshi, Henan province, China—died 664, Chang’an, now Xi’an, China) Buddhist monk and Chinese pilgrim to India who translated the sacred scriptures of Buddhism from Sanskrit into Chinese and founded in China the Buddhist Consciousness Only school. His fame rests mainly on the volume and diversity of his translations of the Buddhist sutras and on the record of his travels in Central Asia and India, which, with its wealth of detailed and precise data, has been of inestimable value to historians and archaeologists.

Born into a family in which there had been scholars for generations, Xuanzang received a classical Confucian education in his youth, but under the influence of an older brother he became interested in the Buddhist scriptures and was soon converted to Buddhism. With his brother he traveled to Chang’an and then to Sichuan to escape the political turmoil that gripped China at that time. While in Sichuan, Xuanzang began studying Buddhist philosophy but was soon troubled by numerous discrepancies and contradictions in the texts. Not finding any solution from his Chinese masters, he decided to go to India to study at the fountainhead of Buddhism. Being unable to obtain a travel permit, he left Chang’an by stealth in 629. On his journey he traveled north of the Takla Makan Desert, passing through such oasis centres as Turfan, Karashar, Kucha, Tashkent, and Samarkand, then beyond the Iron Gates into Bactria, across the Hindu Kush (mountains) into Kapisha, Gandhara, and Kashmir in northwest India. From there he sailed down the Ganges River to Mathura, then on to the holy land of Buddhism in the eastern reaches of the Ganges, where he arrived in 633.

In India, Xuanzang visited all the sacred sites connected with the life of the Buddha, and he journeyed along the east and west coasts of the subcontinent. The major portion of his time, however, was spent at the Nalanda monastery, the great Buddhist centre of learning, where he perfected his knowledge of Sanskrit, Buddhist philosophy, and Indian thought. While he was in India, Xuanzang’s reputation as a scholar became so great that even the powerful king Harsha, ruler of North India, wanted to meet and honour him. Thanks largely to that king’s patronage, Xuanzang’s return trip to China, begun in 643, was greatly facilitated.

Xuanzang returned to Chang’an, the Tang capital, in 645, after an absence of 16 years. He was accorded a tumultuous welcome at the capital, and a few days later he was received in audience by the emperor, who was so enthralled by his accounts of foreign lands that he offered the Buddhist monk a ministerial post. Xuanzang, however, preferred to serve his religion, so he respectfully declined the imperial offer.

Xuanzang spent the remainder of his life translating the Buddhist scriptures, numbering 657 items packed in 520 cases, that he brought back from India. He was able to translate only a small portion of this huge volume, about 75 items in 1,335 chapters, but his translations included some of the most important Mahayana scriptures.

Xuanzang’s main interest centred on the philosophy of the Yogacara (Vijnanavada) school, and he and his disciple Kuiji (632–682) were responsible for the formation of the Weishi (Consciousness Only school) in China. Its doctrine was set forth in Xuanzang’s Chengweishilun (“Treatise on the Establishment of the Doctrine of Consciousness Only”), a translation of the essential Yogacara writings, and in Kuijhi’s commentary. The main thesis of this school is that the whole world is but a representation of the mind. While Xuanzang and Kuiji lived, the school achieved some degree of eminence and popularity, but with the passing of the two masters the school rapidly declined. Before this happened, however, a Japanese monk named Dōshō arrived in China in 653 to study under Xuanzang, and, after he had completed his study, he returned to Japan to introduce the doctrines of the Ideation Only school in that country. During the 7th and 8th centuries, this school, called Hossō by the Japanese, became the most influential of all the Buddhist schools in Japan.

In addition to his translations, Xuanzang composed the Datang-Xiyu-Ji (“Records of the Western Regions of the Great Tang Dynasty”), the great record of the various countries passed through during his journey. Out of veneration for this intrepid and devout Buddhist monk and pilgrim, the Tang emperor canceled all audiences for three days after Xuanzang’s death.

Two studies of Xuanzang are Arthur Waley’s The Real Tripitaka, pp. 11–130 (1952), a popular biography written in a lively and interesting style, and the more complete biography by René Grousset, Sur les traces du Bouddha (1929; In the Footsteps of the Buddha), which discusses the life of the Chinese pilgrim against the background of Tang history and Buddhist philosophy.

Jai Ganesh · 2016-05-21 01:10:35

138. Al-Khwārizmī

Al-Khwārizmī, in full Muḥammad ibn Mūsā al-Khwārizmī (born c. 780—died c. 850) Muslim mathematician and astronomer whose major works introduced Hindu-Arabic numerals and the concepts of algebra into European mathematics. Latinized versions of his name and of his most famous book title live on in the terms algorithm and algebra.

Al-Khwārizmī lived in Baghdad, where he worked at the “House of Wisdom” (Dār al-Ḥikma) under the caliphate of al-Maʾmūn. The House of Wisdom acquired and translated scientific and philosophic treatises, particularly Greek, as well as publishing original research. Al-Kwārizmī’s work on elementary algebra, Al-Kitāb al-mukhtaṣar fī ḥisāb al-jabr waʾl-muqābala (“The Compendious Book on Calculation by Completion and Balancing”), was translated into Latin in the 12th century, from which the title and term Algebra derives. Algebra is a compilation of rules, together with demonstrations, for finding solutions of linear and quadratic equations based on intuitive geometric arguments, rather than the abstract notation now associated with the subject. Its systematic, demonstrative approach distinguishes it from earlier treatments of the subject. It also contains sections on calculating areas and volumes of geometric figures and on the use of algebra to solve inheritance problems according to proportions prescribed by Islamic law. Elements within the work can be traced from Babylonian mathematics of the early 2nd millennium bce through Hellenistic, Hebrew, and Hindu treatises.

In the 12th century a second work by al-Khwārizmī introduced Hindu-Arabic numerals (see numerals and numeral systems) and their arithmetic to the West. It is preserved only in a Latin translation, Algoritmi de numero Indorum (“Al-Khwārizmī Concerning the Hindu Art of Reckoning”). From the name of the author, rendered in Latin as Algoritmi, originated the term algorithm.

A third major book was his Kitāb ṣūrat al-arḍ (“The Image of the Earth”; translated as Geography), which presented the coordinates of localities in the known world based, ultimately, on those in the Geography of Ptolemy (flourished 127–145 ce) but with improved values for the length of the Mediterranean Sea and the location of cities in Asia and Africa. He also assisted in the construction of a world map for al-Maʾmūn and participated in a project to determine the circumference of the Earth, which had long been known to be spherical, by measuring the length of a degree of a meridian through the plain of Sinjār in Iraq.

Finally, al-Khwārizmī also compiled a set of astronomical tables (Zīj), based on a variety of Hindu and Greek sources. This work included a table of sines, evidently for a circle of radius 150 units. Like his treatises on algebra and Hindu-Arabic numerals, this astronomical work (or an Andalusian revision thereof) was translated into Latin.

Jai Ganesh · 2016-05-23 00:12:17

139. John J. Loud

John Jacob Loud (November 2, 1844 – August 10, 1916) was an American inventor known for designing the first ballpoint pen.

Trained as a lawyer at Harvard College, Loud worked at the Union National Bank in Weymouth, Massachusetts as a cashier. He was also active in his community as a member of his church, a trustee of many local organizations, and as a member of local historical societies. Loud invented and obtained a patent for what is considered to be the first ballpoint pen in 1888; however his invention was not commercialized and the patent would eventually lapse. The modern ballpoint pen would be patented later in 1938, 22 years following Loud's death.

Early life and career

Loud was born in Weymouth, Massachusetts in 1844, the son of John White Loud and Sarah Humphrey Blanchard. He attended school in Weymouth, graduating from Weymouth High School, and later attended Harvard College, graduating from the latter in law in the class of 1866. Appointed to the Suffolk County Bar on February 2, 1872, he later furthered his studies in law in the office of Jewell, Gaston & Field, but later opted to join his father in the banking profession. In 1871 he joined his father in working for the Union National Bank as an assistant cashier. Upon his father's death in 1874, Loud assumed his position as cashier, and remained in that post until his resignation in 1895 for health reasons.

Inventions

Keenly interested in inventing, on October 30, 1888, Loud obtained the first patent (US #392,046) for a ballpoint pen when attempting to make a writing instrument that would be able to write on leather products, which then-common fountain pens could not. Loud's pen had a small rotating steel ball, held in place by a socket. In the patent, he noted:

My invention consists of an improved reservoir or fountain pen, especially useful, among other purposes, for marking on rough surfaces-such as wood, coarse wrapping-paper, and other articles where an ordinary pen could not be used.

Although his invention could be used to mark rough surfaces such as leather, as he had originally intended, it proved to be too coarse for letter-writing. With no commercial viability, its potential went unexploited and the patent eventually lapsed.

Loud had also registered patents for a firecracker cannon (1888) and a "toy cannon" (1887).

Personal life, death

Residing in Weymouth, Loud was a member of the Union Congregational Church. He was an active genealogist, and an active member of the Maine Genealogical Society, New Hampshire Genealogical Society, New England Historic Genealogical Society, and Weymouth Historical Society (of which he was a founding member). He was a descendant of Francis Loud, originally of Ipswich, Massachusetts, and Mayflower passengers William Brewster and John Alden. Loud also was a trustee of the Weymouth Savings Banks, Tufts University Library and the Derby Academy, and a conductor of the Union Religious Society choir at Weymouth and in Braintree. A noted orator, he spoke at many local events, including delivering an address upon the building of the first warship at the Fore River Shipyard in 1900. He also wrote poetry and songs in his spare time. One of his sisters, Annie Frances Loud, was a locally noted composer of "sacred music".

He was married to Emily Keith Vickery from November 7, 1872 until her death in November 1911. The couple had eight children. He died at his home in Weymouth on August 10, 1916 and was buried at Village Cemetery in Weymouth.

Jai Ganesh · 2016-05-25 00:42:17

140. Carl Friedrich Gauss, original name Johann Friedrich Carl Gauss (born April 30, 1777, Brunswick [Germany]—died February 23, 1855, Göttingen, Hanover) German mathematician, generally regarded as one of the greatest mathematicians of all time for his contributions to number theory, geometry, probability theory, geodesy, planetary astronomy, the theory of functions, and potential theory (including electromagnetism).

Gauss was the only child of poor parents. He was rare among mathematicians in that he was a calculating prodigy, and he retained the ability to do elaborate calculations in his head most of his life. Impressed by this ability and by his gift for languages, his teachers and his devoted mother recommended him to the duke of Brunswick in 1791, who granted him financial assistance to continue his education locally and then to study mathematics at the University of Göttingen from 1795 to 1798. Gauss’s pioneering work gradually established him as the era’s preeminent mathematician, first in the German-speaking world and then farther afield, although he remained a remote and aloof figure.

Gauss’s first significant discovery, in 1792, was that a regular polygon of 17 sides can be constructed by ruler and compass alone. Its significance lies not in the result but in the proof, which rested on a profound analysis of the factorization of polynomial equations and opened the door to later ideas of Galois theory. His doctoral thesis of 1797 gave a proof of the fundamental theorem of algebra: every polynomial equation with real or complex coefficients has as many roots (solutions) as its degree (the highest power of the variable). Gauss’s proof, though not wholly convincing, was remarkable for its critique of earlier attempts. Gauss later gave three more proofs of this major result, the last on the 50th anniversary of the first, which shows the importance he attached to the topic.

Gauss’s recognition as a truly remarkable talent, though, resulted from two major publications in 1801. Foremost was his publication of the first systematic textbook on algebraic number theory, Disquisitiones Arithmeticae. This book begins with the first account of modular arithmetic, gives a thorough account of the solutions of quadratic polynomials in two variables in integers, and ends with the theory of factorization mentioned above. This choice of topics and its natural generalizations set the agenda in number theory for much of the 19th century, and Gauss’s continuing interest in the subject spurred much research, especially in German universities.

The second publication was his rediscovery of the asteroid Ceres. Its original discovery, by the Italian astronomer Giuseppe Piazzi in 1800, had caused a sensation, but it vanished behind the Sun before enough observations could be taken to calculate its orbit with sufficient accuracy to know where it would reappear. Many astronomers competed for the honour of finding it again, but Gauss won. His success rested on a novel method for dealing with errors in observations, today called the method of least squares. Thereafter Gauss worked for many years as an astronomer and published a major work on the computation of orbits—the numerical side of such work was much less onerous for him than for most people. As an intensely loyal subject of the duke of Brunswick and, after 1807 when he returned to Göttingen as an astronomer, of the duke of Hanover, Gauss felt that the work was socially valuable.

Similar motives led Gauss to accept the challenge of surveying the territory of Hanover, and he was often out in the field in charge of the observations. The project, which lasted from 1818 to 1832, encountered numerous difficulties, but it led to a number of advancements. One was Gauss’s invention of the heliotrope (an instrument that reflects the Sun’s rays in a focused beam that can be observed from several miles away), which improved the accuracy of the observations. Another was his discovery of a way of formulating the concept of the curvature of a surface. Gauss showed that there is an intrinsic measure of curvature that is not altered if the surface is bent without being stretched. For example, a circular cylinder and a flat sheet of paper have the same intrinsic curvature, which is why exact copies of figures on the cylinder can be made on the paper (as, for example, in printing). But a sphere and a plane have different curvatures, which is why no completely accurate flat map of the Earth can be made.

Gauss published works on number theory, the mathematical theory of map construction, and many other subjects. In the 1830s he became interested in terrestrial magnetism and participated in the first worldwide survey of the Earth’s magnetic field (to measure it, he invented the magnetometer). With his Göttingen colleague, the physicist Wilhelm Weber, he made the first electric telegraph, but a certain parochialism prevented him from pursuing the invention energetically. Instead, he drew important mathematical consequences from this work for what is today called potential theory, an important branch of mathematical physics arising in the study of electromagnetism and gravitation.

Gauss also wrote on cartography, the theory of map projections. For his study of angle-preserving maps, he was awarded the prize of the Danish Academy of Sciences in 1823. This work came close to suggesting that complex functions of a complex variable are generally angle-preserving, but Gauss stopped short of making that fundamental insight explicit, leaving it for Bernhard Riemann, who had a deep appreciation of Gauss’s work. Gauss also had other unpublished insights into the nature of complex functions and their integrals, some of which he divulged to friends.

In fact, Gauss often withheld publication of his discoveries. As a student at Göttingen, he began to doubt the a priori truth of Euclidean geometry and suspected that its truth might be empirical. For this to be the case, there must exist an alternative geometric description of space. Rather than publish such a description, Gauss confined himself to criticizing various a priori defenses of Euclidean geometry. It would seem that he was gradually convinced that there exists a logical alternative to Euclidean geometry. However, when the Hungarian János Bolyai and the Russian Nikolay Lobachevsky published their accounts of a new, non-Euclidean geometry about 1830, Gauss failed to give a coherent account of his own ideas. It is possible to draw these ideas together into an impressive whole, in which his concept of intrinsic curvature plays a central role, but Gauss never did this. Some have attributed this failure to his innate conservatism, others to his incessant inventiveness that always drew him on to the next new idea, still others to his failure to find a central idea that would govern geometry once Euclidean geometry was no longer unique. All these explanations have some merit, though none has enough to be the whole explanation.

Another topic on which Gauss largely concealed his ideas from his contemporaries was elliptic functions. He published an account in 1812 of an interesting infinite series, and he wrote but did not publish an account of the differential equation that the infinite series satisfies. He showed that the series, called the hypergeometric series, can be used to define many familiar and many new functions. But by then he knew how to use the differential equation to produce a very general theory of elliptic functions and to free the theory entirely from its origins in the theory of elliptic integrals. This was a major breakthrough, because, as Gauss had discovered in the 1790s, the theory of elliptic functions naturally treats them as complex-valued functions of a complex variable, but the contemporary theory of complex integrals was utterly inadequate for the task. When some of this theory was published by the Norwegian Niels Abel and the German Carl Jacobi about 1830, Gauss commented to a friend that Abel had come one-third of the way. This was accurate, but it is a sad measure of Gauss’s personality in that he still withheld publication.

Gauss delivered less than he might have in a variety of other ways also. The University of Göttingen was small, and he did not seek to enlarge it or to bring in extra students. Toward the end of his life, mathematicians of the calibre of Richard Dedekind and Riemann passed through Göttingen, and he was helpful, but contemporaries compared his writing style to thin gruel: it is clear and sets high standards for rigour, but it lacks motivation and can be slow and wearing to follow. He corresponded with many, but not all, of the people rash enough to write to him, but he did little to support them in public. A rare exception was when Lobachevsky was attacked by other Russians for his ideas on non-Euclidean geometry. Gauss taught himself enough Russian to follow the controversy and proposed Lobachevsky for the Göttingen Academy of Sciences. In contrast, Gauss wrote a letter to Bolyai telling him that he had already discovered everything that Bolyai had just published.

After Gauss’s death in 1855, the discovery of so many novel ideas among his unpublished papers extended his influence well into the remainder of the century. Acceptance of non-Euclidean geometry had not come with the original work of Bolyai and Lobachevsky, but it came instead with the almost simultaneous publication of Riemann’s general ideas about geometry, the Italian Eugenio Beltrami’s explicit and rigorous account of it, and Gauss’s private notes and correspondence.

Jai Ganesh · 2016-05-26 23:15:32

141. Otto Hahn

Otto Hahn, (born March 8, 1879, Frankfurt am Main, Ger.—died July 28, 1968, Göttingen, W.Ger.) German chemist who, with the radiochemist Fritz Strassmann, is credited with the discovery of nuclear fission. He was awarded the Nobel Prize for Chemistry in 1944 and shared the Enrico Fermi Award in 1966 with Strassmann and Lise Meitner.

Early life

Hahn was the son of a glazier. Although his parents wanted him to become an architect, he eventually decided to study chemistry at the University of Marburg. There Hahn worked hard at chemistry, though he was inclined to absent himself from physics and mathematics lectures in favour of art and philosophy, and he obtained his doctorate in 1901. After a year of military service, he returned to the university as chemistry lecture assistant, hoping to find a post in industry later on.

In 1904 he went to London, primarily to learn English, and worked at University College with Sir William Ramsay, who was interested in radioactivity. While working on a crude radium preparation that Ramsay had given to him to purify, Hahn showed that a new radioactive substance, which he called radiothorium, was present. Fired by this early success and encouraged by Ramsay, who thought highly of him, he decided to continue with research on radioactivity rather than go into industry. With Ramsay’s support he obtained a post at the University of Berlin. Before taking it up, he decided to spend several months in Montreal with Ernest Rutherford (later Lord Rutherford of Nelson) to gain further experience with radioactivity. Shortly after returning to Germany in 1906, Hahn was joined by Lise Meitner, an Austrian-born physicist, and five years later they moved to the new Kaiser Wilhelm Institute for Chemistry at Berlin-Dahlen. There Hahn became head of a small but independent department of radiochemistry.

Feeling that his future was more secure, Hahn married Edith Junghans, the daughter of the chairman of Stettin City Council, in 1913; but World War I broke out the next year, and Hahn was posted to a regiment. In 1915 he became a chemical-warfare specialist, serving on all the European fronts.

After the war, Hahn and Meitner were among the first to isolate protactinium-231, an isotope of the recently discovered radioactive element protactinium. Because nearly all the natural radioactive elements had then been discovered, he devoted the next 12 years to studies on the application of radioactive methods to chemical problems.

Discovery of nuclear fission

In 1934 Hahn became keenly interested in the work of the Italian physicist Enrico Fermi, who found that when the heaviest natural element, uranium, is bombarded by neutrons, several radioactive products are formed. Fermi supposed these products to be artificial elements similar to uranium. Hahn and Meitner, assisted by the young Strassmann, obtained results that at first seemed in accord with Fermi’s interpretation but that became increasingly difficult to understand. Meitner fled from Germany in July 1938 to escape the persecution of Jews by the Nazis, but Hahn and Strassmann continued the work. By the end of 1938, they obtained conclusive evidence, contrary to previous expectation, that one of the products from uranium was a radioactive form of the much lighter element barium, indicating that the uranium atom had split into two lighter atoms. Hahn sent an account of the work to Meitner, who, in cooperation with her nephew Otto Frisch, formulated a plausible explanation of the process, to which they gave the name nuclear fission.

The tremendous implications of this discovery were realized by scientists before the outbreak of World War II, and a group was formed in Germany to study possible military developments. Much to Hahn’s relief, he was allowed to continue with his own researches. After the war, he and other German nuclear scientists were taken to England, where he learned that he had been awarded the Nobel Prize for 1944 and was profoundly affected by the announcement of the explosion of the atomic bomb at Hiroshima in 1945. Although now aged 66, he was still a vigorous man; a lifelong mountaineer, he maintained physical fitness during the enforced stay in England by a daily run.

On his return to Germany he was elected president of the former Kaiser Wilhelm Society (renamed the Max Planck Society for the Advancement of Science) and became a respected public figure, a spokesman for science, and a friend of Theodor Heuss, the first president of the Federal Republic of Germany. He campaigned against further development and testing of nuclear weapons. Honours came to him from all sides; in 1966 he, Meitner, and Strassmann shared the prestigious Enrico Fermi Award. This period of his life was saddened, however, by the loss of his only son, Hanno, and his daughter-in-law, who were killed in an automobile accident in 1960. His wife never recovered from the shock. Hahn died in 1968, after a fall; his wife survived him by only two weeks.

Jai Ganesh · 2016-05-30 00:42:20

142. Lewis Waterman

Lewis Edson Waterman (November 18, 1837 – May 1, 1901), born in Decatur, New York, was the inventor of the capillary feed fountain pen and the founder of the Waterman pen company.

Lewis Edson Waterman founded his company in New York in 1883 with the invention of a new feeder. He used the capillarity principle which allowed air to induce a steady and even flow of ink. He worked on his invention for ten years before placing it on the market. Waterman got a patent for his new fountain pens in 1884.

Waterman began selling his fountain pens behind a cigar shop and gave his pens a five-year guarantee. He opened a factory in Montreal, Canada in 1899, offering a variety of designs.

Waterman also invented a successful method for preserving and condensing grape-juice.

Following his death in Brooklyn in 1901, his nephew Frank D. Waterman took the business overseas and increased sales to 350,000 pens per year. After Frank took over, he renamed the business Waterman. S. A.

Waterman was inducted into the National Inventors Hall of Fame in 2006.

Jai Ganesh · 2016-06-01 00:54:08

143. John Bardeen

John Bardeen, (born May 23, 1908, Madison, Wis., U.S.—died Jan. 30, 1991, Boston, Mass.) American physicist who was cowinner of the Nobel Prize for Physics in both 1956 and 1972. He shared the 1956 prize with William B. Shockley and Walter H. Brattain for their joint invention of the transistor. With Leon N. Cooper and John R. Schrieffer he was awarded the 1972 prize for development of the theory of superconductivity.

Bardeen earned bachelor’s and master’s degrees in electrical engineering from the University of Wisconsin (Madison) and obtained his doctorate in 1936 in mathematical physics from Princeton University. A staff member of the University of Minnesota, Minneapolis, from 1938 to 1941, he served as principal physicist at the U.S. Naval Ordnance Laboratory in Washington, D.C., during World War II.

After the war Bardeen joined (1945) the Bell Telephone Laboratories in Murray Hill, N.J., where he, Brattain, and Shockley conducted research on the electron-conducting properties of semiconductors. On Dec. 23, 1947, they unveiled the transistor, which ushered in the electronic revolution. The transistor replaced the larger and bulkier vacuum tube and provided the technology for miniaturizing the electronic switches and other components needed in the construction of computers.

In the early 1950s Bardeen resumed research he had begun in the 1930s on superconductivity, and his Nobel Prize-winning investigations provided a theoretical explanation of the disappearance of electrical resistance in materials at temperatures close to absolute zero. The BCS theory of superconductivity (from the initials of Bardeen, Cooper, and Schrieffer) was first advanced in 1957 and became the basis for all later theoretical work in superconductivity. Bardeen was also the author of a theory explaining certain properties of semiconductors. He served as a professor of electrical engineering and physics at the University of Illinois, Urbana-Champaign, from 1951 to 1975.

Jai Ganesh · 2016-06-03 00:39:08

144. John Boyd Dunlop

John Boyd Dunlop (5 February 1840 – 23 October 1921) was a Scottish-born and educated inventor and veterinary surgeon who spent most of his career in Ireland. Familiar with making rubber devices, he re-invented pneumatic tyres for his child's tricycle and developed them for use in cycle racing. He sold his rights to the pneumatic tyres to a company he formed with the president of the Irish Cyclists' Association, Harvey Du Cros, for a small cash sum and a small shareholding in their pneumatic tyre business. Dunlop withdrew in 1896. The company that bore his name, Dunlop Pneumatic Tyre Company, was not incorporated until later using the name well known to the public, but it was Du Cros's creation.

Veterinary practice

He was born on a farm in Dreghorn, North Ayrshire, and studied to be a veterinary surgeon at the Dickinson Vet, University of Edinburgh, a profession he pursued for nearly ten years at home, moving to Downpatrick, Ireland, in 1867.

Quite early in his life he was told he had been a premature birth, two months before his mother had expected. He convinced himself his health was delicate and throughout his life acted accordingly, but he had no serious illness until he contracted a chill in October 1921 aged 81 and died unexpectedly. Sir Arthur Du Cros described him as a diffident and gentle-mannered man but confident in his abilities.

He married Margaret Stevenson in 1871 and they had a daughter and a son. He established Downe Veterinary Clinic in Downpatrick with his brother James Dunlop before moving to a practice in 38–42 May Street, Belfast where, by the mid 1880s, his was one of the largest practices in Ireland.

Dunlop developed pneumatic tyres for his son's tricycle and soon had them made commercially in Scotland. A cyclist using his tyres began to win all races and drew the attention of Harvey Du Cros. Dunlop sold his rights into a new business with Du Cros for some cash and a small shareholding. With Du Cros he overcame many difficulties experienced by their business, including the loss of his patent rights. In 1892 he retired from his veterinary practice and moved to Dublin soon after Harvey Du Cros with his assistance successfully refloated Booth Bros of Dublin as the Pneumatic Tyre and Booth's Cycle Agency. The pneumatic tyre revolutionised the bicycle industry, which had boomed after the 1885 introduction of J K Starley's safety bicycle.

J B Dunlop sold out in 1895 and took no further interest in the tyre or rubber business. His remaining business interest was a local drapery. He died at his home in Dublin's Ball's Bridge in 1921 and is buried in Deans Grange Cemetery.

Dunlop's image appeared on the £10 note issued by the Northern Bank, which was in circulation in Northern Ireland.

Pneumatic tyres

In October 1887, John Boyd Dunlop developed the first practical pneumatic or inflatable tyre for his son's tricycle and, using his knowledge and experience with rubber, in the yard of his home in Belfast fitted it to a wooden disc 96 centimetres across. The tyre was an inflated tube of sheet rubber. He then took his wheel and a metal wheel from his son's tricycle and rolled both across the yard together. The metal wheel stopped rolling but the pneumatic continued until it hit a gatepost and rebounded. Dunlop then put pneumatics on both rear wheels of the tricycle. That too rolled better, and Dunlop moved on to larger tyres for a bicycle "with even more startling results." He tested that in Cherryvale sports ground, South Belfast, and a patent was granted on 7 December 1888. Unknown to Dunlop another Scot, Robert William Thomson from Stonehaven, had patented a pneumatic tyre in 1847.

Willie Hume demonstrated the supremacy of Dunlop's tyres in 1889, winning the tyre's first-ever races in Ireland and then England. The captain of the Belfast Cruisers Cycling Club, he became the first member of the public to purchase a bicycle fitted with pneumatic tyres, so Dunlop suggested he should use them in a race. On 18 May 1889 Hume won all four cycling events at the Queen's College Sports in Belfast, and a short while later in Liverpool, won all but one of the cycling events. Among the losers were sons of the president of the Irish Cyclists' Association, Harvey Du Cros. Seeing an opportunity, Du Cros built a personal association with J B Dunlop, and together they set up a company which acquired his rights to his patent.

Two years after he was granted the patent, Dunlop was officially informed that it was invalid as Scottish inventor Robert William Thomson (1822–1873), had patented the idea in France in 1846 and in the US in 1847. see Tyres. To capitalise on pneumatic tyres for bicycles, Dunlop and Du Cros resuscitated a Dublin-listed company and renamed it Pneumatic Tyre and Booth's Cycle Agency. Dunlop retired in 1895. In 1896 Du Cros sold their whole bicycle tyre business to British financier Terah Hooley for £3 million. Hooley arranged some new window-dressing, titled board members, etc., and re-sold the company to the public for £5 million. Du Cros remained head of the business until his death. Early in the 20th century it was renamed Dunlop Rubber.

Though he did not participate after 1895, Dunlop's pneumatic tyre did arrive at a crucial time in the development of road transport. His commercial production of cycle tyres began in late 1890 in Belfast, but the production of car tyres did not begin until 1900, well after his retirement. J B Dunlop did not make any great fortune by his invention. He was inducted into the Automotive Hall of Fame in 2005.

Jai Ganesh · 2016-06-04 21:45:32

145. Leo Hendrik Baekeland

An American chemist, inventor, and manufacturer, Leo Hendrik Baekeland (1863-1944) invented Bakelite, the first plastic to be used widely in industry.

Leo Ernst Baekeland was born in 1863 in Ghent, Belgium. He took a bachelor of science degree from the University of Ghent in 1882 and began to teach there as an assistant professor; he received his doctorate in natural science in 1884 and continued to teach for another 5 years. In 1889 he went to the United States on a traveling scholarship, liked the country, received a job offer from a photographic firm, and decided to make America his home.

These were the years when science was first coming to the attention of American industry. In some European countries, notably Germany, industrial research was already helping to improve old products and processes and to develop new ones. This wedding of science and technology was just beginning in the United States, first in those industries that had been close to science from their beginnings, such as the chemical and electrical industries. The manufacture of photographic equipment and materials was one such industry. Baekeland began work to improve photographic film, and in 1893 he established the Nepera Chemical Company to manufacture Velox paper, a film of his invention which could be handled in the light. In 1899 he sold out to the leading firm in the field, Eastman Kodak, and used the money to set up his own private industrial research laboratory in a converted barn behind his home in Yonkers, N.Y.

At this laboratory Baekeland began a large number of experiments covering a range of subjects. One of these was an attempt to produce a synthetic shellac by mixing formal-dehyde and phenolic bodies. Other experimenters had worked with these two substances, and it was known that the interaction was greatly influenced by the proportions used and the conditions under which they were brought together. Baekeland failed to synthesize shellac but instead discovered Bakelite, the first successful plastic.

Earlier plastics had only limited usefulness because of their tendency to soften when heated, harden when cooled, and interact readily with many chemical substances. Baekeland's new material did not suffer from any of these defects. Using temperatures much higher than previously thought possible, he developed a process for placing the material in a hot mold and adding both pressure and more heat so that a chemical change would take place, transforming the material in composition as well as shape.

He patented this process in 1909 and formed the Bakelite Corporation the following year to market the material. Bakelite soon became very successful and was widely used in industry as a substitute for hard rubber and amber, particularly in electrical devices. He retired from the company in 1939, honored for his success as a manufacturer and for his effectiveness as a spokesman for the whole concept of scientific research in the aid of industry.

Jai Ganesh · 2016-06-06 01:11:13

146. Wolfgang Amadeus Mozart

Wolfgang Amadeus Mozart was an Austrian composer (a writer of music) whose mastery of the whole range of contemporary (modern) instrumental and vocal forms—including the symphony, concerto, chamber music, and especially the opera—was unchallenged in his own time and perhaps in any other.

Child prodigy

Wolfgang Amadeus Mozart was born on January 27, 1756, in Salzburg, Austria. His father, Leopold Mozart, a noted composer, instructor, and the author of famous writings on violin playing, was then in the service of the archbishop of Salzburg. Leopold and Anna Maria, his wife, stressed the importance of music to their children. Together with his sister, Nannerl, Wolfgang received such intensive musical training that by the age of six he was a budding composer and an accomplished keyboard performer. In 1762 Leopold presented his son as performer at the imperial court in Vienna, Austria, and from 1763 to 1766 he escorted both children on a continuous musical tour across Europe, which included long stays in Paris, France, and London, England, as well as visits to many other cities, with appearances before the French and English royal families.

Mozart was the most celebrated child prodigy (an unusually gifted child) of this time as a keyboard performer. He also made a great impression as a composer and improviser (one who arranges or creates). In London he won the admiration of musician Johann Christian Bach (1735–1782), and he was exposed from an early age to an unusual variety of musical styles and tastes across Europe.

Gaining fame

From the age of ten to seventeen, Mozart's reputation as a composer grew to a degree of maturity equal to that of most older established musicians. He spent the years from 1766 to 1769 at Salzburg writing instrumental works and music for school dramas in German and Latin, and in 1768 he produced his first real operas: the German Singspiel (that is, with spoken dialogue) Bastien und Bastienne. Despite his growing reputation, Mozart found no suitable post open to him; and his father once more escorted Mozart, at age fourteen (1769), and set off for Italy to try to make his way as an opera composer.

In Italy, Mozart was well received: in Milan, Italy, he obtained a commission for an opera; in Rome he was made a member of an honorary knightly order by the Pope; and at Bologna, Italy, the Accademia Filarmonica awarded him membership despite a rule normally requiring candidates to be twenty years old. During these years of travel in Italy and returns to Salzburg between journeys, he produced his first large-scale settings of opera seria (that is, court opera on serious subjects): Mitridate (1770), Ascanio in Alba (1771), and Lucio Silla (1772), as well as his first string quartets. At Salzburg in late 1771 he renewed his writing of Symphonies (Nos. 14–21).

In Paris and Vienna

Paris was a vastly larger theater for Mozart's talents. His father urged him to go there, for "from Paris the fame of a man of great talent echoes through the whole world," he wrote his son. But after nine difficult months in Paris, from March 1778 to January 1779, Mozart returned once more to Salzburg, having been unable to secure a foothold and depressed by the entire experience, which had included the death of his mother in the midst of his stay in Paris. Unable to get hired for an opera, he wrote music to order in Paris, again mainly for wind instruments: the Sinfonia Concertante for four solo wind instruments and orchestra, the Concerto for flute and harp, other chamber music, and the ballet music Les Petits riens. In addition, he began giving lessons to make money.

Mozart's years in Vienna, from age twenty-five to his death at thirty-five, cover one of the greatest developments in a short span in the history of music. In these ten years Mozart's music grew rapidly beyond the realm of many of his contemporaries; it exhibited both ideas and methods of elaboration that few could follow, and to many the late Mozart seemed a difficult composer.

The major instrumental works of this period bring together all the fields of Mozart's earlier activity and some new ones: six symphonies, including the famous last three: no. 39 in E-flat Major, no. 40 in G Minor, and no. 41 in C Major (the Jupiter —a title unknown to Mozart). He finished these three works within six weeks during the summer of 1788, a remarkable feat even for him.

In the field of the string quartet Mozart produced two important groups of works that completely overshadowed any he had written before 1780: in 1785 he published the six Quartets (K. 387, 421, 428, 458, 464, and 465) and in 1786 added the single Hoffmeister Quartet (K. 499). In 1789 he wrote the last three Quartets (K. 575, 589, and 590), dedicated to King Frederick William (1688–1740) of Prussia, a noted cellist.

Operas of the Vienna years

Mozart's development as an opera composer between 1781 and his death is even more remarkable, perhaps, since the problems of opera were more far-ranging than those of the larger instrumental forms and provided less adequate models. The first important result was the German Singspiel entitled Die Entführung aus dem Serail (1782; Abduction from the Seraglio ). Mozart then turned to Italian opera. Mozart produced his three greatest Italian operas: Le nozze di Figaro (1786; The Marriage of Figaro ), Don Giovanni (1787, for Prague), and Cosi fan tutte (1790). In his last opera, The Magic Flute (1791), Mozart turned back to German opera, and he produced a work combining many strands of popular theater and including musical expressions ranging from folk to opera.

On concluding The Magic Flute, Mozart turned to work on what was to be his last project, the Requiem. This Mass had been commissioned by a benefactor (financial supporter) said to have been unknown to Mozart, and he is supposed to have become obsessed with the belief that he was, in effect, writing it for himself. Ill and exhausted, he managed to finish the first two movements and sketches for several more, but the last three sections were entirely lacking when he died. It was completed by his pupil Franz Süssmayer after his death, which occurred in Vienna, Austria, on December 5, 1791.

Jai Ganesh · 2016-06-07 22:44:44

147. Dwight Filley Davis (July 5, 1879 – November 28, 1945) was an American tennis player and politician. He is best remembered as the founder of the Davis Cup international tennis competition. He was the Assistant Secretary of War from 1923 to 1925 and Secretary of War from 1925 to 1929.

Dwight Filley Davis was born in St. Louis, Missouri on July 5, 1879.

He reached the All-Comers final for the Men's Singles title at the US Championships in 1898 and 1899. He then teamed up with Holcombe Ward and won the Men's Doubles title at the championships for three years in a row from 1899 to 1901. Davis and Ward were also Men's Doubles runners-up at Wimbledon in 1901. Davis also won the American intercollegiate singles championship of 1899 as a student at Harvard College.

In 1900 Davis developed the structure for, and donated a silver bowl to go to the winner of, a new international tennis competition designed by him and three others known as the International Lawn Tennis Challenge, which was later renamed the Davis Cup in his honor. He was a member of the US team that won the first two competitions in 1900 and 1902, and was also the captain of the 1900 team.

He participated in the 1904 Summer Olympics. He was eliminated in the second round of the singles tournament. In the doubles tournament he and his partner Ralph McKittrick lost in the quarter-finals.

Davis was educated at Washington University Law School, though he was never a practicing attorney. He was, however, politically active in his home town of St. Louis and served as the city's public parks commissioner from 1911 to 1915. During his tenure, he expanded athletic facilities and created the first municipal tennis courts in the United States. He served President Calvin Coolidge as Assistant Secretary of War (1923–25) and as Secretary of War (1925–29). He then served as Governor General of the Philippines (1929–32) under Herbert Hoover. His first wife, Helen Brooks, whom he married in 1905, died in 1932. He married Pauline Sabin in 1936. He wintered in Florida from 1933 until his death, living at Meridian Plantation, near Tallahassee. Davis died in Washington, D.C. on November 28, 1945.

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