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== =ISAAC NEWTON (25 December 1642 - 20 March 1727)= (By Cherine, Aliza, Rosemarie, Kaylynn, Jixin)

__**Biography**__  Isaac Newton is the culminating figure in the Scientific Revolution of the 17th century and is arguably one of the most influential scientists in history.  Newton was an English experimenter, empiricist, and university mathematician, and he is still considered today as the greatest single scientific mind of all time. His various theories and discoveries still hold true centuries after his death and with countless experiments, many of them still affecting us at the present. People even had the general impression that "somehow, Newton had done it all, that no important problems remained".

Newton entered Cambridge University in 1661; where he was elected a Fellow of Trinity College in 1667 and Lucasian Professor of Mathematics in 1669, and remained at the university lecturing in most years until 1696. Of these years in Cambridge, in which Newton was at the height of his creative power, he singled out 1665-1666 (spent largely in Lincolnshire because of plague in Cambridge) as "the prime of my age for invention". During two to three years of intense mental effort he prepared //Philosophiae Naturalis Principia MathematicaMathematial Principles of Natural Philosophy)// commonly known as the //Principia,// although this was not published until 1687. As a firm opponent of the attempt by King James II to make the universities into Catholic institutions, Newton was elected Member of Parliament for the University of Cambridge to the Convention Parliament of 1689, and sat again in 1701-1702. Meanwhile, in 1696 he had moved to London as Warden of the Royal Mint. He became Master of the Mint in 1699, an office he retained to his death. He was elected a Fellow of the Royal Society of London in 1671, and in 1703 he became President, being annually re-elected for the rest of his life. His major work, //Opticks,// appeared the next year; he was knighted in Cambridge in 1705.  In terms of religion he accepted the Church of England only partially and over time he came to see the Bible more as an allegory than as undisputed fact. However, he believed it vain and scientifically improper to seek out an underlying explanation for what he still saw as God's handiwork (ironically). He felt that what could be understood, with mathematical certainty, was how the universe operated as it did, and that trying to understand why the world was as it is would lead to futile speculation. As what he once said: //hypotheses non fingo//, "I frame no hypothesis".

He offered irrefutable proof -- of course, mathematical proof -- that Nature had order and meaning, an order and meaning that was not based on faith but on human Reason. For Newton, there was the important combination of two important concepts -- Nature and Reason. He shared the Cartesians' belief in the power of mathematics to describe nature, but he disagreed with their indifference to studying the behaviour of objects in nature. He respected the observation of nature. Newton's geometry thus was backed by evidence from the world of everyday observation and experience which not only proved his theories, but also showed how practical his conclusions were.  As Newtonian science became increasingly accepted on the Continent, and especially after a general peace was restored in 1714, following the War of the Spanish Succession, Newton became the most highly esteemed natural philosopher in Europe. His last decades were passed in revising his major works, polishing his studies of ancient history, and defending himself against critics, as well as carrying out his official duties. Newton was modest, diffident, and a man of simple tastes. He was angered by criticism or opposition, and harboured resentment; he was harsh towards enemies but generous to friends. In government, and at the Royal Society, he proved an able administrator. He never married and lived modestly, but was buried with great pomp in Westminster Abbey. Newton has been regarded for almost 300 years as the founding examplar of modern physical science, his achievements in experimental investigation being as innovative as those in mathematical research. With equal, if not greater, energy and originality he also plunged into chemistry, the early history of Western civilization, and theology; among his special studies was an investigation of the form and dimensions, as described in the Bible, of Solomon's Temple in Jerusalem. His scientific discoveries and his spirit (together with the ideas of Francis Bacon and John Locke) dominated the thought of the 18th century -- a century the thinkers of the period itself called the Age of Enlightenment.

__**Timeline** ( of Newton's life and accomplishments) __


 * Key events** (overview)


 * 1642- Born in the little English village of Woolsthorpe
 * 1666 - 1667: Returned to Woolsthorpe, invented Calculus, Mathematcal means of calculating rates of change, began investigations into Composition of Light, inaugurated his work on the law of Universal Gravitation
 * 1669: Accepted Chair in mathematics in Cambridge
 * 1672: Presented results on his work on Optics to the Royal Society, but orovoked series of arguments with the then society's president, Robert Hooke
 * 1672 - 1677: Investigated the fundamental problems of motion
 * 1684 - 1686: Wrote // Principia //
 * 1687: //Principia Mathematica// published
 * 1693: Received administrative post as warden of Royal Mint
 * 1699: Advanced to Master of Mint
 * 1703: Made President of Royal Society
 * 1705: Knighted for his great achievements
 * 1714: // General Scholium // was published


 * Alternative Timeline (detailed)**

December 25 1642 - Isaac Newton (1642-1727) is born at Woolsthorpe prematurely and posthumously. His survival was in question for some time, and by tradition Newton was small enough to fit into a small 'quart pot'. In 1655 he attended Grammar School at nearby Grantham, aged 12. Then in 1661, Newton matriculates at Trinity College in Cambridge, is elected scholar in 1664, and takes his Bachelor Degree in 1665.
 * 1665 ** - August - Newton departs Cambridge due to the Plague and moves back temporarily to Woolsthorpe, unwittingly continuing his // Anni Mirabliles // (1664-1666). His work at Woolsthorpe for the next 18 months is now legendry.

February 6 - Newton sends Oldenburg his first letter on Light and Colors, which is read to the Society and criticized harshly by Robert Hooke, a respected senior scientist and Curator of Experiments for the Royal Society. February 8 - Newton publishes his letter on Light & Colors in the // Philosophical Transactions; // it is arguably the first 'scientific article' June 13 - Newton sends his // Epistola prior // to Oldenburg. October 20 - Newton sends his // Epistola posterior // to Oldenburg. November - Newton sends his short treatise // De motu // to London; December 10 - // De motu // is received by Royal Society; Newton writes his // De composito serierum // and // Mathesos universalis. // Leibniz publishes his // Novus methodus //, his first publication calculus, which appears to have resulted from his entirely independent efforts. It resulted in an infamous priority dispute with Newton, who had earlier arrived at similar results, though he failed to put them into print. May 19 - Royal Society decided to publish // Principia. // July 5 - // Principia // appears in print. November 30 - Newton is elected to the Council of the Royal Society. December 10 - Newton resigns his position as Lucasian chair of mathematics. November 30 - Newton is elected President of Royal Society. May 27 - Newton refuses to grant publication of // Short Chronology // but publishes it later that year. March 18 - Newton's health fails, he collapses and borders on death. March 20 - Isaac Newton dies at Kensington between 1.00 and 2.00am. March 28 - Newton's body lays in state in Westminster Abbey. April 4 - Newton's body is buried at Westminster Abbey.
 * 1667 ** - October 2 - Newton is elected minor Fellow of Trinity College; he writes // Enumeratio curvarum. //
 * 1669 ** - October 29 - Newton is elected Lucasian Professor of Mathematics.
 * 1671 ** - Newton writes // De methodis // ; in December he sends his reflecting ('Newtonian') telescope to Royal Society.
 * 1672 ** - January 11 - Newton is elected Fellow of the Royal Society of London.
 * 1675 ** - December 9 - 16 - Newton's Hypothesis explaining the Properties of Light is read before Royal Society.
 * 1676 ** - January 20 - February 10 - Discourse of Observations read to Royal Society.
 * 1679 ** - November 24 - first of a series of letters exchanged with Robert Hooke, a philosophical correspondence on the problem of planetary motion.
 * 1680 ** - December 12 - Newton begins to observe the Comet of 1680-81; he writes // Geometria curvilinea. //
 * 1681 ** - Newton observes the Comet until March and corresponds with John Flamsteed (1646-1719) on the topic.
 * 1682 ** - December - Newton observes 'Halley's' comet.
 * 1684 ** - August - Edmond Halley (1656-1742) makes his famous Cambridge visit to inquire of Newton about the path of a planet moving in relation to an inverse-square. Newton later begins work on his // Principia //.
 * 1685 ** - February 23 - // De motu // had been entered in the Register of the Royal Society.
 * 1686 ** - April 28 - Newton presents his // Principia //, Book I to the Royal Society.
 * 1687 ** - April 11 - Newton is appointed by Cambridge Senate as one of the representatives in the Francis affair.
 * 1693 ** - July - August - Newton suffers emotional breakdown.
 * 1695 ** - Newton reworks his // Enumeratio curvarum // ; he writes his // Tabula refractionum //.
 * 1696 ** - March 19 - Newton is offered an appointment as Warden of the Mint by Charles Montagu; Newton accepts.
 * 1699 ** - February 21 - Newton is elected Foreign Associate of the Académie des sciences (Paris).
 * 1700 ** - February 3 - Newton is appointed Master of the Mint.
 * 1701 ** - November 26 - Newton elected to Parliament by Cambridge Senate.
 * 1702 ** - Autumn. - Newton publishes // Lunae theoria. //
 * 1703 ** - March 3 - Robert Hooke dies; Newton decides to go forward in publishing his work on optics, work completed years before.
 * 1704 ** - February Newton publishes the first edition of his // Opticks //.
 * 1705 ** - April 16 - Newton is Knighted by Queen Anne in Cambridge, thereafter, he is known as Sir Isaac Newton.
 * 1706 ** - first Latin edition of Newton's // Opticks // with its Queries.
 * 1707 ** - Newton publishes // Arithmetica universalis. //
 * 1710 ** - September - Newton publishes: // De natura acidorum //, // Enumeratio // and // De quadratura Lexicon technicum //.
 * 1711 ** - Newton publishes // Analysis per quantitatum. //
 * 1713 ** - January - Newton publishes // Commercium epistolicum //.
 * 1717 ** - May 16 - Newton publishes second English edition of // Opticks // with eight queries.
 * 1719 ** - Newton publishes second Latin edition of the // Opticks. //
 * 1720 ** - Publication of the first English edition of // Universal Arithmetic //
 * 1721 ** - Newton publishes third English edition of // Opticks. //
 * 1722 ** - Publication of second edition of // Commercium epistolicum // with the addition of the // Recensio //
 * 1726 ** - March 31 - Newton publishes third edition of // Principia //.
 * 1727 (Newton's Final Days) ** - March 2 - Newton attends Royal Society for last time.

__**Newton's Role in Scientific Revolution: Major discoveries and inventions**__

Isaac Newton, as one of the foremost scientific intellects of all time, is a key figure in the scientific revolution. Newton obsessive personality led him to make new discoveries and improve on existing instruments and machines. This is because, once he became involved with a problem, it consumed his efforts for months and years at a time. He dismantled the larger question into its component parts and studied them to exhaustion. Furthermore, if he lacked the tools to do his experiment properly, Newton built his own.


 * IN MATHEMATICS**

__Calculus__

In 1665, Isaac Newton invented the generalized binomial theorem and started working on the development of a mathematical theory, which went on to become the infinitesimal calculus, a very important branch of mathematics. Newton laid the foundation for elementary differential and integral calculus. It is a mathematical means of calculating rates of change. The "method of fluxions," as he termed it, was based on his crucial insight that the integration of a function (or finding the area under its curve) is merely the inverse procedure to differentiating it (or finding the slope of the curve at any point).

//Significance// Taking differentiation as the basic operation, Newton produced simple analytical methods that unified a host of disparate techniques previously developed on a piecemeal basis to deal with such problems as finding areas, tangents, the lengths of curves, and their maxima and minima.This method is a powerful tool of problem solving and analysis in pure mathematics and physics. For example, in October 1666 he applied them to several problems in the theory of equations. It is also used to describe planets' orbital movements.

These discoveries represented a quantum leap in the fields of math and science allowing for calculations that more accurately modeled the behavior of the universe than ever before. Newton discovered many of the laws and theories that not only furthered our understanding of the universe, but also gave future scientists the tools to discover how to enter space. Without these advances in math, scientists could not design vehicles to carry us and other machines into space and also plot the best and safest course. Calculus gave scientist the tools to set up a theoretical model of a situation and still account for varying factors. This basic knowledge would help scientist such as Einstein to be able make even greater discoveries such as the Theory of Relativity and Nuclear Fission.

//Achievements// Isaac Barrow, a Fellow of Trinity College and Lucasian Professor of Mathematics in the University, was so impressed by Newton's achievement that when he resigned his chair in 1669 to devote himself to theology, he recommended that the 27-year-old Newton take his place.

//Publication// Newton's //De Methodis Serierum et Fluxionum//

__Newton’s identities__

Newton’s identities, which are used to find the relationship between power sums and elementary symmetric polynomials and the Newton’s method that is used for finding successive approximations of a real-valued function, were some of the other important discoveries of Sir Isaac Newton. The first successful use of the power series in polynomial theory is attributed to Newton. He also devised a new formula to calculate Pi.


 * IN MECHANICS AND GRAVITATION**

__Law of Universal Gravitation/ Motion__

Newton refined Galileo's theory of inertia, which suggested that:
 * only a change in motion required a cause;
 * objects either stayed in motion or remained at rest;
 * equal and opposite "forces" of motion were at work when any two objects came into contact

His observation led him to the discovery of the gravitational force. It was Newton who showed that the gravitational force extends across the Earth. He further demonstrated that the planets were attracted toward the Sun by a force varying as the inverse square of the distance and generalized that all heavenly bodies mutually attract one another. By further generalization, he reached his law of universal gravitation: every piece of matter attracts every other piece with a force proportional to the product of their masses and inversely proportional to the square of the distance between them.

The Newton’s Laws of Motion became the founding principle of mechanics and enlightened the masses about the relationships between force and motion.

//Newton's laws of motion//
 * 1) In the absence of a net force, a body either is at rest or moves in a straight line with constant speed.
 * 2) A body experiencing a force **F** experiences an acceleration **a** related to **F** by **F** = //m//**a**, where //m// is the mass of the body. Alternatively, force is equal to the time derivative of mometum.
 * 3) Whenever a first body exerts a force **F** on a second body, the second body exerts a force −**F** on the first body. **F** and −**F** are equal in magnitude and opposite in direction.

He also devised the principles of angular momentum and the conservation of momentum. //Significance// Given the law of gravitation and the laws of motion, Newton could also explain and investigate a wide range of hitherto disparate phenomena such as the motion of many physical objects and systems like the motion of bodies in free space, the motion of bodies in a resisting medium, and the solar system and celestial movements under the action of centripetal forces, the eccentric orbits of comets, the causes of the tides and their major variations, the precession of the Earth's axis, and the perturbation of the motion of the Moon by the gravity of the Sun. His theory also led to the calculation of the orbital period of the Moon. It offered single, clear, mathematical description of forces at work for understanding motion of the planets and on earth. For example, in the third volume of the text-"Philosophieae Naturalis Principia Mathematica", Newton showed that these laws of motion, combined with his law of universal gravitation, explained Kepler's laws of planetary motion. Another example of how Newton's law of motion explaines the motion of physical object is that using the 3rd law, we understand the reason behind what happens if we step off a boat onto the bank of a lake: as we move in the direction of the shore, the boat tends to move in the opposite direction.

Newton's one general law of nature and one system of mechanics reduced to order most of the known problems of astronomy and terrestrial physics. The work of Galileo, Copernicus, and Kepler was united and transformed into one coherent scientific theory. The new Copernican world-picture finally had a firm physical basis.

Newton's law of motion and univeral gravitation could be applied to daily life to help people solve problems such as helping engineers design new kinds of working parts for machinery, causing a gigantic leap in an age of seaborne empires and maritime trade- mathematics of gravity could be used to predict the ebb and flow of tides, even in waters where European ships had never sailed, provided an orderly and comprehensive picture of the heavens and earth, the push and pull of gravitation also showed geographers that the earth was not a perfect sphere, which altered the nature of mapmaking and lastly, gave humanity greater power over its environment due to the practicality of his conclusions. In particular, the third of Newton's law of motion is essential to the understanding of modern rocket power and jet propulsion.

Newton had an influence on natural philosophers in the 18th century. He reverted in the early 1700s to the idea that some sort of material medium, or ether, caused gravity. But Newton's ether was no longer a Cartesian-type ether acting solely by impacts among particles. The ether had to be extremely rare so it would not obstruct the motions of the planets, and yet very elastic or springy so it could push large masses toward one another. Newton postulated that the new ether consisted of particles endowed with very powerful short-range repulsive forces. His unreconciled ideas on forces and ether deeply influenced later natural philosophers in the 18th century when they turned to the phenomena of chemistry, electricity and magnetism, and physiology.

//Publication//

"Philosophieae Naturalis Principia Mathematica" was written in 1687. This book is regarded as one of the most significant literary works in science. It earned Newton international acclaim. It is a compilation of newton's law of motion that describe the relationship between the forces acting on a body and the motion of that body.

Book I of the //Principia// states the foundations of the science of mechanics, developing upon them the mathematics of orbital motion round centres of force. Newton identified gravitation as the fundamental force controlling the motions of the celestial bodies. He never found its cause. To contemporaries who found the idea of attractions across empty space unintelligible, he conceded that they might prove to be caused by the impacts of unseen particles.

Book II inaugurates the theory of fluids: Newton solves problems of fluids in movement and of motion through fluids. From the density of air he calculated the speed of sound waves. Book III shows the law of gravitation at work in the universe: Newton demonstrates it from the revolutions of the six known planets, including the Earth, and their satellites. However, he could never quite perfect the difficult theory of the Moon's motion. Comets were shown to obey the same law; in later editions, Newton added conjectures on the possibility of their return. He calculated the relative masses of heavenly bodies from their gravitational forces, and the oblateness of Earth and Jupiter, already observed. He explained tidal ebb and flow and the precession of the equinoxes from the forces exerted by the Sun and Moon. All this was done by exact computation.

In addition to Principia, Newton wrote The Universal Arithmetic, which help to substantiate and advance his theory of equations. He also wrote papers concerning calculus, curves, optics, and analytical geometry.

**IN OPTICS** __Composition of Light__

Newton made two important discoveries: 1. Each "colour" of light was a component of white light. He had reached the revolutionary conclusion that white light is not a simple, homogeneous entity, as natural philosophers since Aristotle had believed. When he passed a thin beam of sunlight through a glass prism, he noted the oblong spectrum of colors--red, yellow, green, blue, violet--that formed on the wall opposite.

2. The colours came into focus at different distances. Newton showed that the spectrum was too long to be explained by the accepted theory of the bending (or refraction) of light by dense media. The old theory said that all rays of white light striking the prism at the same angle would be equally refracted. Newton argued that white light is really a mixture of many different types of rays, that the different types of rays are refracted at slightly different angles, and that each different type of ray is responsible for producing a given spectral color. A so-called crucial experiment confirmed the theory. Newton selected out of the spectrum a narrow band of light of one color. He sent it through a second prism and observed that no further elongation occurred. All the selected rays of one color were refracted at the same angle. Each ray is also definable by the angle through which it is refracted on entering or leaving a given transparent medium. He correlated this notion with his study of the interference colours of thin films (for example, of oil on water, or soap bubbles), using a simple technique of extreme acuity to measure the thickness of such films. He held that light consisted of streams of minute particles. From his experiments he could infer the magnitudes of the transparent "corpuscles" forming the surfaces of bodies, which, according to their dimensions, so interacted with white light as to reflect, selectively, the different observed colours of those surfaces.

His work led to the discovery that a prism can decompose white light into a spectrum of colors. He was successful in demonstrating that a combination of a lens and a prism could recompose a spectrum of colors into white light.

He discovered that color is an outcome of objects reflecting colored light. This discovery became famous by the name, ‘Newton’s Theory of Color’.

Newton investigated the refraction of light by a glass prism; developing over a few years a series of increasingly elaborate, refined, and exact experiments, Newton discovered measurable, mathematical patterns in the phenomenon of colour.

Newton also made improvements on existing instruments. He improved ordinary prisms in order to understand the nature of light and colour and build a new lens for telescopes that focused the colours accurately and produced much clearer images. His discovery that the colours came into focus at different distances led Newton to the logical, but erroneous, conclusion that telescopes using refracting lenses could never overcome the distortions of chromatic dispersion. He therefore proposed and constructed a reflecting telescope, the first of its kind, and the prototype of the largest modern optical telescopes. And he is famed for his invention of the reflecting telescope.

//Significance//

It paved the way for more indepth, detailed observation of light.  //Publications// Newton published his first scientific paper in the Philosophical Transactions of the society. It dealt with the new theory of light and color and is one of the earliest examples of the short research paper.

Newton's Opticks appeared in 1704. It dealt with the theory of light and color and with Newton's investigations of the colors of thin sheets, of "Newton's rings," and of the phenomenon of diffraction of light. To explain some of his observations he had to graft elements of a wave theory of light onto his basically corpuscular theory.

//Experiments in Optics// Newton's main interest at the time of his appointment was optics, and for several years the lectures required of him by the professorship were devoted to this subject. In a letter of 1672 to the secretary of the Royal Society, he says that in 1666 he had bought a prism "to try therewith the celebrated phenomena of colours." He continues, "In order thereto having darkened the room and made a small hole in my window-shuts to let in a convenient quantity of the Suns light, I placed my prism at its entrance, that it might be thereby refracted to the opposite wall." He had been surprised to see the various colors appear on the wall in an oblong arrangement (the vertical being the greater dimension), "which according to the received laws of refraction should have been circular." Proceeding from this experiment through several stages to the "crucial" one, in which he had isolated a single ray and found it unchanging in color and refrangibility, he had drawn the revolutionary conclusion that "Light itself is a heterogeneous mixture of differently refrangible rays." These experiments had grown out of Newton's interest in improving the effectiveness of telescopes, and his discoveries about the nature and composition of light had led him to believe that greater accuracy could not be achieved in instruments based on the refractive principle. He had turned, consequently, to suggestions for a reflecting telescope made by earlier investigators but never tested in an actual instrument. Being manually dexterous, he built several models in which the image was viewed in a concave mirror through an eyepiece in the side of the tube. In 1672 he sent one of these to the Royal Society. Newton felt honored when the members were favorably impressed by the efficiency of his small reflecting telescope and when on the basis of it they elected him to their membership. But when this warm reception induced him to send the society a paper describing his experiments on light and his conclusions drawn from them, the results were almost disastrous for him and for posterity. The paper was published in the society's //Philosophical Transactions,// and the reactions of English and Continental scientists, led by Robert Hooke and Christiaan Huygens, ranged from skepticism to bitter opposition to conclusions which seemed to invalidate the prevalent wave theory of light. At first Newton patiently answered objections with further explanations, but when these produced only more negative responses, he finally became irritated and vowed he would never publish again, even threatening to give up scientific investigation altogether. Several years later, and only through the tireless efforts of the astronomer Edmund Halley, Newton was persuaded to put together the results of his work on the laws of motion, which became the great //Principia.//

Newton left a mass of manuscripts on the subjects of alchemy and chemistry, then closely related topics. Most of these were extracts from books, bibliographies, dictionaries, and so on, but a few are original. He began intensive experimentation in 1669, continuing till he left Cambridge, seeking to unravel the meaning that he hoped was hidden in alchemical obscurity and mysticism. He sought understanding of the nature and structure of all matter, formed from the "solid, massy, hard, impenetrable, movable particles" that he believed God had created. Most importantly in the "Queries" appended to "Opticks" and in the essay "On the Nature of Acids" (1710), Newton published an incomplete theory of chemical force, concealing his exploration of the alchemists, which became known a century after his death.
 * IN ALCHEMY AND CHEMISTRY**

Newton owned more books on humanistic learning than on mathematics and science; all his life he studied them deeply. His unpublished "classical scholia"—explanatory notes intended for use in a future edition of the //Principia//—reveal his knowledge of pre-Socratic philosophy; he read the Fathers of the Church even more deeply. Newton sought to reconcile Greek mythology and record with the Bible, considered the prime authority on the early history of mankind. In his work on chronology he undertook to make Jewish and pagan dates compatible, and to fix them absolutely from an astronomical argument about the earliest constellation figures devised by the Greeks. He put the fall of Troy at 904 BC, about 500 years later than other scholars; this was not well received.
 * IN HISTORICAL AND CHRONOLOGICAL STUDIES**

Newton also wrote on Judaeo-Christian prophecy, whose decipherment was essential, he thought, to the understanding of God. His book on the subject, which was reprinted well into the Victorian Age, represented lifelong study. Its message was that Christianity went astray in the 4th century AD, when the first Council of Nicaea propounded erroneous doctrines of the nature of Christ. The full extent of Newton's unorthodoxy was recognized only in the present century: but although a critic of accepted Trinitarian dogmas and the Council of Nicaea, he possessed a deep religious sense, venerated the Bible and accepted its account of creation. In late editions of his scientific works he expressed a strong sense of God's providential role in nature.
 * IN RELIGIOUS CONVICTIONS AND PERSONALITY**

__Positions held__

During his later years, Newton was the President of the Royal Society and was associated with the French Academie des Sciences, a learned society established with an aim of promoting French scientific research.

__**References**__
History Handout

Accomplishments:

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Timeline: http://www.clas.ufl.edu/users/ufhatch/pages/13-NDFE/newton/05-newton-timeline-m.htm