A GREAT SCIENTIST.

Otago Daily Times, Issue 20075, 16 April 1927, Page 19

A GREAT SCIENTIST.

BICENTENARY OF SIR ISAAC NEWTON. CELEBRATIONS IN ENGLAND. The 200th anniversary of the death of Sir Isaac Newton occurred on March 20, and in England his great services to science were celebrated on that dale. At Grantham, the Lincolnshire toivn associated with his boyhood, and with some of Ins oarlv discoveries, there was a meeting of scientists, at which several addresses on Newton's work were given. The gathering made a pilgrimage of six miles to the manor house at Woolsthorpe, whore Newton was born. In the room in which he first eaw the light there is a tablet inscribed with the celebrated epitaph written by Tope:— Nature and Nature’s laws lay hidden in night; God said. “Let Newton be,’ and all was light. It is impossible to over-estimate the value of Newton’s discoveries in various branches of science at a time when science was m its infancy. It was his good fortune to have his work recognised during his lifetime. The Royal Society, composed of men of learning, encouraged him m his work, and at the age of 29 ho was electee, a fellow of the society chiefly because ot his valuable researches into the science of optics. He remained a distinguished member ot that society until his death in 1727, at the age of 84; and for the last 25 years of his life he filled the post ot president of the society, being re-elected each year. In order to enable him to carry on his researches he was appointed in 1696 warden of the Mint at a salary of £6OO a year. In those times money had five times the purchasing power it has to-day. The Mint, according to Macaulay, was “a nest of idlers and jobber?, bu the ability, the industry, and the strict uprightness of the great philosopher speedily produced a complete revolution throughou the department which was under his direction.” Newton also did valuable work at the Mint in connection with the ie coinage of the currency; but after this work he rthniiiJsr^ kni'ghin ie i7o5 U ?or' his to and on his death he was buried in W estmi i n n to Newton was short; his features were sharp and his nose promi nent He had blue eyes and a square, determined jaw. In dress he was untidy and slovenly, and while engaged in research work he was very absent-minded In money matters be was generous and charitable. He was modest despite ma fame, and the high regard in wlncbhc was held by men of distinction, he was deeply religious and transparently honest. But* he was easily upset, and the c°ntro vcrsics in which he became involved with other scientists who disputed his theories, or who claimed to have preceded him in hia discoveries, caused him much mental dktrS ln these controversies he does not appear as a generous opponent. In the light of later discoveries some of his theories, particularly those dealin" with the science of optics, have been found to bo erroneous; and Einsteins theory of relativity has displaced Newton’s daw of gravitation. But Newton did an immense amount of valuable which stands as an imperishable monumorit of his fame. And even in those departments of science in which h i a thcorics have been upset, it is undeniable that he blazed the path for others. It ma> be said that it was because of his gicat achievements that even his erroneous theories remained unchallenged for generations. This is particularly the case with his law of gravitation, which was not definitely superseded until in 191 J Einstein’s theory of relativity was P r °^ tl to be correct, by means of observations of certain stars near the sun, taken dur ing the total eclipse of the sun. Newton was the posthumous child of a small farmer at Woolsthorpe. who died a few months after marriage. His mother married again after three years ofwidowhood, and had three children by her second husband. At school he showed an aptitude for mechanical contrivances, and constructed windmills, water clocks, dials, and kites. His step-father died when the boy was 15 years old, and he was t_kcn from school by his mother in order to become a farmer; but as he spent more time over books than on the farm be was sent back to school. His uncle, the rector of the adjoining parish, who had been a graduate of Trinity College, Cambridge, urged his mother to send him to that college so that his aptitude for mechanical and mathematical problems could be developed. At the university he made himself familiar with Euclidean geometry, geometrical conics, algebra, trigonometry, analytical geometry, and tor his own amusement worked at optics and chemistry. In 1605 and again in 1066 Trinity College was closed on account of the plague—l 666 was the year of England a terrible visitation of the plague, when London lost over 100,000 of its population of 400,000 inhabitants. Newton was elected a fellow of Trinity College in 1667, and on account of his genius for mathematics was appointed Lucasian professor in 1669. It was his duty as professor to lecture at least once a week in terra time on some portion of geometry, arithmetic, astronomy, geography, optics, statics, or some other mathematical subject, and also for two hours in the week to allow an audience to any student who might come to consult with the professor on anv difficulties he had met with. Newton chose the subject of optics for his lectures, and gave his pupils the benefit ot bis remarkable experiments and discoveries. In 1672 he put before the Royal Society the substance of those lectures in a paper dealing with the spectrum and the composition of light. The experiments ho described and the results achiev'd by them created a groat stir in scio’ tifie circles. Newton continued his investigations and succeeded in explaining the inflexion of light. He wrote on double refraction, polarisation and_ binocular vision. Ho invented a reflecting sextant for observing the distance between the moon and the fixed stars—the same in every essential as the instrument which is still in everyday use at sea under the name of Hadlev’s quadrant. It was "in the autumn of 1665. at Woolsthorpe, that the idea of universal gravitation first occurred to him. “As he sat alone in a garden,’’ says Pemberton, his intimate friend of later years, “ho fell into a speculation on the power of gravity, that, as this power is not found sensibly diminished at the remotest distance from the centre, of the earth to which we can rise .... it appeared to him reasonable to conclude that this power must extend much farther than U usually thought. Whv not as high as the moon? said ho to himself, and if so. her motion must bo influenced by it; perhaps she is retained in her orbit thereby.’’ The story of Newton’s attention was drawn to the problem of gravitation by seeing an apple fall from a tree in the garden was first published by Voltaire, in his “Philosophic de Newton.” Voltaire had the story from Newton’s niece. Catherine Barton, who married Conduitt, ’a fellow of_ the Royal Society, and one of Newton’s intimate friends. Tradition singled out a tree in the garden of the manor'houso at Woolsthorpe as the one from which the apple fell. This Deo remained there until 1820. when it was so decayed that it was ent down. But it was not until 20 years had elapsed that Newton completed his theory of the universal law of gravitation. On April 21, 1686, his friend Halley read to the Royal Society a paper entitled “Discourse Concerning Gravity and its Properties,’ in which ho stated' that, “mv worthy countryman, Mr Isaac Newton has an incomparable treatise of motion almost ready for the press," and that the law of (lie inverse square "is tho principle on which Mr Newton has made out all (ho nhenomena of the celestial motions so easily ami naturally that its truth is past dispute.” At the meeting ot tho society, seven days later. Dr Vincent presented a manuscript treatise entitled Philosophise Naturalis Princinia Mathematica. which was “dedicated to tho society by Mr Isaac Newton.” This was the fir=t book of Newton’s famous “Principia.” The complete work, consisting of three books, was published in the following year. It represented a profound contribution to science, and it created a stir throughout scientific circles in Europe. It gave mankind a more comprehensive conception _ of tho universe than had hitherto prevailed, and it established Newton’s fame on an imperishable basis. In the “Principia” he discussed tho motion of bodies in free space in known orbits, or under the action of known forces, generalising tho law of attraction into the statement that every particle of matter attracts every other particle with a force varying directly as the product of their masses, and inversely as tho square of the ,|!,ta"Ce Pet,Venn them.

It is impossible _to estimate the genius of Newton. Voltaire, wiio was present at his funeral, and was profoundly impressed l\v the honours paid .to his memory by the chief men of (he nation, said of him. "If all the geniuses of the world assembled. Newton should load the band.” Laplace, the most_ famous of French astronomers, who in his clay was known as the French Newton, declared that Newton’s “Prim cipia” was assured of "a pre-eminence above all other productions of the human intellect.” In contrast with these estimates, there is Newton's own modest opinion of Lis work. *T do not know what I may appear to the work!,” ho said, Jiortlv before his death, “but to mvself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother nebblo or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.”