A GREAT DISCOVERER

Evening Star, Issue 21720, 15 May 1934, Page 13

A GREAT DISCOVERER

CAREER DF MICHAEL FARADAY When, on. August 29, 1831, Michael Faraday discovered the true relation between electricity and magnetism, ho laid the foundation of achievements which were to make his name famous as one of the greatest benefactors to mankind; To-day, a little more than. 100 years after his experiment, the principle of electro-magnetic induction has been so greatly advanced and so widely applied that the world depends upon it almost solely for light, heat, and motive power. To Michael Faradqy the world owes as great a debt as has ever been due to a man of science. Long before his day the scientists and philosophers of ancient Greece and Rome had observed the phenomena of electricity in magnetic attraction and lightning. Their knowledge, however, was scanty; and no systematic experiments were conducted before the time of William Gilbert (1544-1603), whose work, *On the Magnet, Magnetic Bodies, and the Great Magnet, the Earth,’ laid the foundation of the science on an experimental and inductive basis. In the seventeenth and eighteenth centuries there was widespread research into the properties of electricity (which Gilbert had named), chiefly notable for the work of Benjamin Franklin, Henry Cavendish, and C. A. Coulomb: . In 1799 Allesandro Volta devised his - famous “voltaic pile, consisting of discs of copper and zinc or other, metals, .with wet cloths placed between the pairs, which proved that all metals could be arranged in an electromotive series such that each became positive when placed in contact with the one next below it in the senes. The early years of the nineteenth century brought the celebrated memoir on electrodynamics hy_ A. H. Ampere, and the mathematical investigations of the voltaic circuit conducted by Dr G. S. Ohm, originator of Ohm’s LawNot. until Michael Faraday’s experiment of August 29, 1831, was the true relation: discovered between electricity and magnetism, from which have been derived almost all the developments in electricity during the last century. _ On that day he wound two coils of wire on to the opposite sides of a soft iron ring, connected one coil to a battery and the other to a galvanometer. At “ make ’ and “ break ” of the battery he observed ■■ deflections; of the connected in the other circuit. ; Thhs, in ten days of brilliant investigation, guided by clear insight frpm the very first, he established the principle which has been so vastly developed in modern civilisation. In a paper which he read before the Royal Society in November of the same year, Faraday showed by these experiments that to produce'an induced electric current in a conductor, it was necesAary only to cause the conductor to cut approximately what hfe called “ magnetic curves.!’ . All the generators used’ at the present time for the mechanical production of electric currents are based on this principle. His third great discovery was the effect of magnetism on light.

BRILLIANT THEORIES. Ifc was'hot the bare ;discovery of these scientific facts which has made Faraday so famous. He is known and remembered because the discoveries ■were clothed by his imagination with , theories and explanations of remarkable brilliance, theories and explanations which are still the basis for most calculations, in electricity. : It is all the more strange, therefore/that such a mind did ~nqt,, sce, or at least did. not predict, any of the great, advances which', have been made in the practical development and rises of electric power. This failure is probably due partly_ to the fact .that the idea of mechanical power in quantity was new to the world of his time, and not altogether welcome. There was no demand for generators and motors; and perhaps it is hard to expect even a visionary scientist to foresee the _ fulfilment of a demand not inherent in human nature and almost unknown to his age. The question, what is the use of electricity? he parried by another“Of what use is a baby?” He was implying, perhaps, that just as no one could tell .the future of a child, so it was not for him'to prophesy the future development of the power which he had released. Almost'before the end of his life; however, the experimental or engineering period of electricity was beginning. Before his death cables had been laid from England to Holland and from England to America. The engineering world had awakened, to thq possibilities of electricity, and scientist, engineer, and' mechanic were combining their knowledge in an effort to produce hew and better types of motive machi-, nery. ; Faraday’s methods of work are of timely interest in the present age of research. He had an amazing capacity for detail, never passing an observation until he had first striven to find its fullest explanation. In a rough note book called his “ Commonplace Book,” he entered every perplexity, letting it stand-until the answer could be found. Thus he was never without a new subject for lesearch. One of these questions; entered in 1824 was “How to convert magnetism into electricity.” It was seven years before he answered that question, and in the experiments * which answered it established the greatest principle of ■ his life’s research. Shortly afterwards he discovered that wires carrying currents can have an inductive effect upon other wires placed near them, and can cause secondary currents to flow in them. To illustrate this he made the first transformer, which, though constructed on a coreof solid iron with wire “ insulated” with string and strips of calico, proved eminently successful for the work, and is still preserved to-day in the museunr of the Royal Institute. Again the importance may be emphasised of the interpretations which he placed on these experiments, interpretations which the mathematicians of a later age were able to express in symbols and ultimately as electrical formulae. EARLY HANDICAPS. Between 1708 and 1730 •'here were entered in the parish register at Clapham, Yorkshire, the births of ten children of Richard Faraday, who is described as a stonemason and tiler. There is reason to believe that an eleventh child, Robert, was born, but not registered. This Robert’s third son was Michael Faraday’s father. Michael was bom in 1791 at Newington, Sur- < rey, but when he was five years of age his father moved to rooms in Jacob’s Well MewSj London, and brought up his family in the atmosphere of reeking stables. The family was in poor cicumstances, and when in 1801 the of wheat rose to 22s fid a bushel each child was allowed only one loaf a week. Until he was fourteen Michael Faraday had had no education at all, though he had managed to learn reading. When at that age he was apprenticed to a bookbinder he began to read all thei scientific works which passed through his hands. So well did he take advantage of all opportunities of study that at the age of twenty-two, withmA using an influence except his own per-

sonality, he was appointed assistant to Sir Humphry Davy, then one of the foremost scientists of England, at the Royal Institute Laboratory. Davy took him on an extensive tour of the European centres of learning, during which, though he became more a valet than a secretary, ho began to contribute regularly to the various scientific periodicals of the day, articles on the more intricate developments of physics and chemistry. About this time (1820) Oersted, a German scientist, discovered the fact that an electric current in a wire produces a magnetic effect, the magnetic forces behaving as though they were concentrated in cylindrical shells round the wire. Faraday wrote a paper on this subject for the Royal Society, in which he showed a mental conception of the processes involved in this simple fact far ahead of the other experimenters of the day. They knew merely that a fact was so; Faraday showed that he had some clear idea why it was so. From then onwards his attention was turned to experiments in electricity, and discovery followed discovery in rapid succession. And with each discovery came a ready explanation of the cause and a theory predicting future discoveries. The one characteristic which lifted Faraday so far above the other experimenters of the time was this ability to explain the phenomena which he discovered. Ydt his electro-magnetic work was then merely a side-line to his appointment as assistant lecturer, and finally as professor of chemistry at the Royal Institute. From 1835 until 1850, Farraday advanced his experimental researches in almost every branch of science, and increased his fame as lecturer and experimenter. It was during these years that he published that classical work which is still a standard reference boob for electrical engineers, ‘ Experimental Researches in Electricity.’ The mental strain of his activities, together with injuries to his eyes, forced him temporarily to retire; but after making a quick recovery, he returned with new vigour to the problems of electricity that so fascinated him. It was during these later years of his work that he made a discovery from which, though it has contributed more than any other to his scientific fame, no directly practical result has been achieved. This was the effect of magnetism on light, an experimental fact which several mathematical physicists were predicting, which. Faraday himself knew must exist; but which had so far baffled research. He found that a beam of polarised light had its plane of polarisation rotated by being passed through a strong magnetic, field. This discovery gave the mathematicians the assurance for which they were waiting, and led ultimately to the discovery of waves by Hertz aud to their application in wireless transmission by Marconi and others., Towards the end of his life Faraday was called to honorary membership of nearly every scientific society in the world, and was on intimate terms with the leading spirits of Europe and America. He was consulted by Parliament on many important scientific problems, and was of great value to the naval administration in the design of early, models of steamcraft. , , , Just as his knowledge had been acquit ed with difficulty, so it was dispensed liberally. Great Britain was fortunate in the possession of so ripe a counsellor on the growing branches of physical science. His life came to a quiet end in 1886, after a few years of rest from a work which had occupied him for half a century and which had led the way for a century ot_protress in electrical science. The Faraay centenary, which was celebrated last year, culminated in a huge exhibition, at the Royal Albert Hall, London of the manifold applications of electricity which 1 had been derived from his work as , a pioneer.