National Geographic : 1949 Apr
Isaac Newton (1642-1727) W AS THERE EVER ANOTHER such story as that of young Isaac Newton, the schoolboy with no liking for books, whose mind ten years later was wandering with com plete assurance among the problems and enigmas of the heavenly bodies, and who was to achieve thereby immortal fame? He made known to a world which still be lieved in witchcraft the laws of gravitation, and by his experiments with the spectrum dis covered that light consists of rays differently refrangible. His amazing intellect worked out as if by magic astronomical problems that had puzzled the astronomer Edmund Halley. Isaac Newton, a puny and premature infant, was born on Christmas Day at Woolsthorpe Manor near Colsterworth, Lincolnshire, in the year that witnessed the outbreak of the Civil War between Cavalier and Roundhead. New ton's father, a substantial yeoman farmer, died before his son's birth. The house is now preserved as a national heritage, thanks to the Pilgrim Trust, founded by the American philanthropist, the late Edward S. Harkness. Three years after her husband's death New ton's mother married the Reverend Barnabas Smith, whose parish lay in another part of the county, and little Isaac was left in the charge of his grandmother. At the age of twelve he was sent to Gran tham Grammar School, a shy and retiring boy. When a school bully taunted him, how ever, the unexpected happened. Young New ton thrashed the bully. That scrap was the turning point in his career. Within two years he was head of the school. At sixteen he left school to become a farmer like his father, and to look after the family estate. Fortunately for mankind, Isaac did not like country pursuits. He was sent back to school to prepare for Trinity College, Cam bridge. There his interest in mathematics was quickened by Isaac Barrow, whom he was destined one day to succeed. When the plague brought learning at Cam bridge to a standstill, Newton, then 22, re turned home and in two wonder years began his series of great discoveries in physics. "I began," he wrote, "to think of gravity extending to the orb of the Moon . . . having thereby compared the force requisite to keep the Moon in her orb with the force of gravity at the surface of the earth, and found the an swer pretty nearly. All this was in the two plague years, 1665 and 1666, for in those years I was in the prime of age for invention, and minded Mathematicks and Philosophy more than at any time since." Prof. Sherwood Taylor says that in these years Newton arrived at the binomial theorem, the differential calculus (or fluxionss" as he called it), the principle of universal gravita tion, and the connection of color and refraction -although he did not publish his discoveries for many years. Halley visited Newton at Cambridge and reported to the Royal Society that Mr. New ton had showed him a curious treatise con cerning motion, and that he had requested Newton to communicate with the Society. This Newton did the following year. The incident was the beginning of the Royal Society's interest in Newton's monumental work, PhilosophiaeNaturalis PrincipiaMathe matica, which was printed by Samuel Pepys, then president of the Society. His most important contribution to scien tific thought was his exposition of the plan of the solar system and the principles by which it was to be understood. Copernicus was re sponsible for the heliocentric system in 1543. Galileo "had given visual evidence that sup ported this view." Kepler "had discovered the ellipticity of the planetary orbits and the laws that govern their motions." Newton drew inspiration from all these seers and in Principia completed their work. At Cambridge he had delivered the lectures describing his optical experiments, made on a prism he bought at Stourbridge Fair in 1666 the discoveries which led to his theory of light. When Newton gave up his Cambridge pro fessorship, he came to live in London, and, in 1703, he was elected president of the Royal Society. This position he filled with great profit to it until his death 24 years later. His investigations into the order of Nature deepened his reverence for God. At the height of his fame he modestly said: "To myself I seem to have been as a child picking up stones on the sea-shore and diverting myself in now and then finding a smoother pebble or a pret tier shell than ordinary, while the great ocean of truth lay all undiscovered before me." Although Newton's three great laws of motion are still as accurate as ever for the purposes of our workaday world, Einstein's theories of relativity have altered somewhat our concept of the universe as a whole. New ton's laws showed the universe to be a vast interlocking machine which obeyed the uni versal "force" of gravitation. Space was a fixed frame of reference through which motion of a heavenly body could be measured ab solutely, as a ship's motion can be measured through the sea. Einstein has shown that nothing in the universe is fixed and immovable, that the motion of any one body is merely relative to other bodies which also are in motion.